U.S. patent application number 16/329812 was filed with the patent office on 2019-06-27 for polypeptide exhibiting affinity to antibodies forming non-native three-dimensional structure.
This patent application is currently assigned to NATIONAL INSTITUTE OF ADVANCED INDUSTRIAL SCIENCE AND TECHNOLOGY. The applicant listed for this patent is NATIONAL INSTITUTE OF ADVANCED INDUSTRIAL SCIENCE AND TECHNOLOGY. Invention is credited to Shinya HONDA, Hideki WATANABE.
Application Number | 20190194249 16/329812 |
Document ID | / |
Family ID | 61300790 |
Filed Date | 2019-06-27 |
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United States Patent
Application |
20190194249 |
Kind Code |
A1 |
WATANABE; Hideki ; et
al. |
June 27, 2019 |
POLYPEPTIDE EXHIBITING AFFINITY TO ANTIBODIES FORMING NON-NATIVE
THREE-DIMENSIONAL STRUCTURE
Abstract
The present invention relates to a novel polypeptide having
affinity for proteins partially including a CH1-CL domain forming a
non-native three-dimensional structure and capable of being
suitably used for detecting, immobilizing, or removing these
proteins and relates to use of the polypeptide. Specifically,
disclosed are a polypeptide consisting of an amino acid sequence
represented by any one of the following formulas 1 to 3: (1)
P-Q-x-I-x-L-x-[IL]-[NT]-[YW] (SEQ ID NO: 1), (2)
Y-D-P-E-T-G-T-W-P-Q-x-I-x-L-x-[IL]-[NT]-[YW] (SEQ ID NO: 4), and
(3) P--N-S-G-G-G-G-S-Y-D-P-E-T-G-T-W-P-Q-x-I-x-L-x-[IL]-[NT]-[YW]
(SEQ ID NO: 7) (wherein x represents an amino acid residue; and
brackets represent any one of the amino acid residues within the
brackets), and a method of using the polypeptide to detect, purify,
or remove a protein partially including a CH1-CL domain forming a
non-native three-dimensional structure.
Inventors: |
WATANABE; Hideki; (Ibaraki,
JP) ; HONDA; Shinya; (Ibaraki, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
NATIONAL INSTITUTE OF ADVANCED INDUSTRIAL SCIENCE AND
TECHNOLOGY |
Tokyo |
|
JP |
|
|
Assignee: |
NATIONAL INSTITUTE OF ADVANCED
INDUSTRIAL SCIENCE AND TECHNOLOGY
Tokyo
JP
|
Family ID: |
61300790 |
Appl. No.: |
16/329812 |
Filed: |
August 31, 2017 |
PCT Filed: |
August 31, 2017 |
PCT NO: |
PCT/JP2017/031315 |
371 Date: |
March 1, 2019 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C07K 2317/34 20130101;
C07K 2319/70 20130101; C07K 7/08 20130101; C12N 2799/02 20130101;
C07K 1/22 20130101; C07K 7/06 20130101; C07K 16/065 20130101; C07K
16/42 20130101; C12N 15/62 20130101; C07K 2317/32 20130101; C07K
2317/92 20130101; C12N 7/00 20130101; C07K 2317/522 20130101; C07K
16/005 20130101; C07K 2318/20 20130101 |
International
Class: |
C07K 1/22 20060101
C07K001/22; C07K 7/06 20060101 C07K007/06; C12N 15/62 20060101
C12N015/62; C07K 16/06 20060101 C07K016/06; C12N 7/00 20060101
C12N007/00 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 1, 2016 |
JP |
2016-170867 |
Claims
1. A polypeptide consisting of an amino acid sequence represented
by Formula 1: TABLE-US-00013 (1) (SEQ ID NO: 1)
P-Q-x-I-x-L-x-[IL]-[NT]-[YW]
(wherein x represents an amino acid residue, and brackets represent
any one of the amino acid residues within the brackets), or a
polypeptide consisting of an amino acid sequence having addition of
one or several amino acid residues in the amino acid sequence
represented by Formula 1, wherein the polypeptide has affinity for
a CH1-CL domain of immunoglobulin G.
2. The polypeptide according to claim 1, wherein the polypeptide is
a polypeptide consisting of an amino acid sequence represented by
SEQ ID NO: 2 or 3: TABLE-US-00014 (SEQ ID NO: 2) PQEIRLILNW (SEQ ID
NO: 3) PQWITLTITY
or a polypeptide consisting of an amino acid sequence having
addition, deletion, substitution, or insertion of one amino acid
residue in the amino acid sequence represented by SEQ ID NO: 2 or
3, wherein the polypeptide has affinity for a CH1-CL domain of
immunoglobulin G.
3. A polypeptide consisting of an amino acid sequence represented
by Formula 2: TABLE-US-00015 (2) (SEQ ID NO: 4)
Y-D-P-E-T-G-T-W-P-Q-x-I-x-L-x-[IL]-[NT]-[YW]
(wherein x represents an amino acid residue, and brackets represent
any one of the amino acid residues within the brackets) or a
polypeptide consisting of an amino acid having one or several amino
acid residues in the amino acid sequence represented by Formula 2,
wherein the peptide has affinity for a CH1-CL domain of
immunoglobulin G.
4. The polypeptide according to claim 3, wherein the polypeptide is
a polypeptide consisting of an amino acid sequence represented by
any one of SEQ ID NOs: 5, 6, and 36 to 41: TABLE-US-00016 (SEQ ID
NO: 5) YDPETGTWPQEIRLILNW (SEQ ID NO: 6) YDPETGTWPQWITLTITY (SEQ ID
NO: 36) HNFTLPLWMYYDPETGTWPQEIRLILNW (SEQ ID NO: 37)
RFPLMFGPSWYDPETGTWPQEIRLILNW (SEQ ID NO: 38)
RFYVLLDSSWYDPETGTWPQEIRLILNW (SEQ ID NO: 39)
VSKFYPLWTRYDPETGTWPQEIRLILNW (SEQ ID NO: 40)
VFLVLMGPEFYDPETGTWPQEIRLILNW (SEQ ID NO: 41)
FLLFCPRSLCYDPETGTWPQEIRLILNW
or a polypeptide consisting of an amino acid sequence having
addition, deletion, substitution, or insertion of one or two amino
acid residues in the amino acid sequence represented by any one of
SEQ ID NOs: 5, 6, and 36 to 41,wherein the polypeptide has affinity
for a CH1-CL domain of immunoglobulin G.
5. A polypeptide consisting of an amino acid sequence represented
by Formula 3: TABLE-US-00017 (3) (SEQ ID NO: 7)
P-N-S-G-G-G-G-S-Y-D-P-E-T-G-T-W-P-Q-x-I-x- L-x-[IL]-[NT]-[YW]
(wherein x represents an amino acid residue, and brackets represent
any one of the amino acid residues within the brackets), or a
polypeptide consisting of an amino acid sequence having one or
several amino acid residues in the amino acid sequence represented
by Formula 3, wherein the peptides have affinity for a CH1-CL
domain of immunoglobulin G.
6. The polypeptide according to claim 5, wherein the polypeptide is
a polypeptide consisting of an amino acid sequence represented by
any one of SEQ ID NOs: 8 to 12: TABLE-US-00018 (SEQ ID NO: 8)
PNSGGGGSYDPETGTWPQEIRLILNW (SEQ ID NO: 9)
PNSGGGGSYDPETGTWPQWITLTITY (SEQ ID NO: 10)
PNSGGGGSYDPETGTWAQEIRLILNW (SEQ ID NO: 11)
PNSGGGGSYDPETGTWPAEIRLILNW (SEQ ID NO: 12)
PNSGGGGSYDPETGTWPQEIRLIANW
or a polypeptide consisting of an amino acid sequence having
addition, deletion, substitution, or insertion of one to three
amino acid residues in the amino acid sequence represented by any
one of SEQ ID NOs: 8 to 12, wherein the polypeptides have affinity
for a CH1-CL domain of immunoglobulin G.
7. A tandem polypeptide having the polypeptide according to claim 1
with a second polypeptide at the amino-terminus, the
carboxyl-terminus, or both termini thereof, wherein the tandem
polypeptide has affinity for a CH1-CL domain of immunoglobulin
G.
8. A fusion protein having a protein bound to the amino-terminus,
the carboxy-terminus, or both termini of the polypeptide according
to claim 1, wherein the fusion protein has affinity for a CH1-CL
domain of immunoglobulin G.
9. The protein according to claim 8, consisting of an amino acid
sequence represented by any one of SEQ ID NOs: 13 to 15 and 42 to
46.
10. A nucleic acid encoding the polypeptide according to claim
1.
11. The nucleic acid according to claim 10, consisting of a
nucleotide sequence represented by any one of SEQ ID NOs: 16 to 18
and 47 to 51.
12. A recombinant vector comprising the nucleic acid according to
claim 10.
13. A transformant into which the recombinant vector according to
claim 12 is introduced.
14. A recombinant phage or a recombinant virus comprising the
nucleic acid according to claim 10.
15. A modified polypeptide according to claim 1 bound to an organic
compound or an inorganic compound or both an organic compound and
an inorganic compound, wherein the modified polypeptide has
affinity for a CH1-CL domain of immunoglobulin G.
16. An immobilized polypeptide, wherein the polypeptide according
to claim 1 is immobilized on a water-insoluble solid-phase
support.
17. A kit for detecting, purifying, immobilizing, or removing a
protein partially including a CH1-CL domain of immunoglobulin G,
the CH1-CL domain being forming a non-native three-dimensional
structure, the kit comprising the polypeptide according to claim
1.
18. A method for detecting a protein partially including a CH1-CL
domain of immunoglobulin G, the CH1-CL domain being forming a
non-native three-dimensional structure, the method comprising: (1)
contacting a test sample suspected to be contaminated with the
protein including the CH1-CL domain, with the polypeptide according
to claim 1; and (2) determining whether or not a bond is formed
between the protein including the CH1-CL domain and the
polypeptide.
19. A method for purifying a protein partially including a CH1-CL
domain of immunoglobulin G, the CH1-CL domain being forming a
non-native three-dimensional structure, the method comprising: (1)
contacting a sample containing the protein including the CH1-CL
domain with the polypeptide according to claim 1 to bind the
protein including the CH1-CL domain to the polypeptide; and (2)
collecting the protein including the CH1-CL domain bound to the
polypeptide from the sample.
20. A method for removing a protein partially including a CH1-CL
domain of immunoglobulin G, the CH1-CL domain being forming a
non-native three-dimensional structure, the method comprising: (1)
contacting a sample containing the protein including the CH1-CL
domain with the polypeptide according to claim 1, to bind the
protein including the CH1-CL domain to the polypeptide; and (2)
removing the protein including the CH1-CL domain bound to the
polypeptide.
Description
TECHNICAL FIELD
Related Application
[0001] The present application claims the priority of Japanese
Patent Application No. 2016-170867 (filed Sep. 1, 2016), the
disclosure of which is incorporated herein by reference.
Technical Field
[0002] The present invention relates to a polypeptide having a
specific affinity for a protein partially including a CH1-CL domain
forming a non-native three-dimensional structure among proteins
including a CH1-CL domain of an antibody such as immunoglobulin G
(IgG) or a Fab region thereof, and to a method for detecting,
immobilizing, or removing the protein using the affinity
polypeptide.
BACKGROUND ART
[0003] The so-called antibody drugs, which utilize monoclonal
antibodies for therapeutic applications, have annual sales of more
than 30 billion dollars and are the largest biopharmaceutical
products and the fastest growing segment in the entire
pharmaceutical industry. Until now, 23 full-size monoclonal
antibodies have been launched, and some of which are already
blockbusters with annual sales of more than one billion dollars.
The drug candidate monoclonal antibodies whose clinical trials were
initiated from 1995 to 2007 have more than tripled, and the number
has continued to grow further (Non Patent Literature 1).
[0004] With the progress of clinical application of antibodies, as
next generation antibodies, low-molecular-weight antibodies, such
as Fab regions, are also being developed as a form of antibody
molecules having higher tissue penetration or of antibody molecules
with a reduced manufacturing cost (Non Patent Literature 2). As of
2015, three products of Fab regions have been approved as
therapeutic antibodies by the FDA. It is expected that such
low-molecular-weight antibodies will continue to be developed to
complement disadvantages of high-molecular-weight IgG
antibodies.
[0005] With such growth and expansion of the antibody drugs market,
research and development relating to the creation and improvement
of molecules having affinity for antibodies have been actively
conducted. This is because such molecules are useful for research,
manufacture, and analysis of antibodies and so on, particularly
because a great demand is expected in affinity purification and
quality control at the time of manufacturing antibody drugs.
[0006] Currently, research and development of various approaches on
polypeptides having affinity for antibodies are being conducted,
and some of which will be described below.
[0007] Suzuki et al. used a phage library displaying linear
peptides of 7 or 12 residues on filamentous bacteriophage M13 for
identifying a plurality of polypeptides having affinity for the Fc
region of human IgG and measured whether affinity for the Fc region
is present or not by enzyme-linked immunosorbent assay (ELISA)
(Patent Literature 1). They produced a peptide as the common
sequence extracted from the identified plurality of polypeptides
and validated the binding of the peptide to human IgG and also
validated the affinity for the Fc region of IgG derived from a
horse, a sheep, a rabbit, a guinea pig, a goat, a cat, a dog, a
bovine, a pig, and a mouse by ELISA.
[0008] DeLano et al. used a phage library displaying cyclic
peptides represented by Xaai Cys Xaaj Cys Xaak (wherein i, j, and k
are integers satisfying i+j+k=18) circularized through disulfide
bonds on filamentous bacteriophage M13 to obtain a plurality of
cyclic peptides of 20 residues which competitively react with
protein A derived from Staphylococcus aureus for binding to human
IgG. They further produced a cyclic peptide Fc-III which consisted
of 13 residues as the common sequence extracted from these peptides
and found that the peptide had a competitive inhibition ability of
Ki=100 nM in a competitive reaction with protein A (Non Patent
Literature 3) and disclosed that in an experiment using rabbits,
the Fab half-life in vivo could be improved by fusing the Fab
fragment, which is the antigen binding site of IgG, with Fc-III
(Patent Literature 2). Dias et al. produced FcBP-2 by introducing
further circularization into this cyclic peptide Fc-III by using
Pro residues in the D- and L-forms and succeeded in increasing the
affinity (binding dissociation constant of Fc-III: KD=185 nM) for
IgG up to KD=2 nM (Non Patent Literature 4).
[0009] Fassina et al. performed screening of a synthetic
tetrapolypeptide library represented by (Arg Thr Xaa)4 Lys2 Lys Gly
having a branched structure due to the Lys residue to produce a
protein A mimetic (PAM) peptide competing with protein A (Non
Patent Literature 5). It was demonstrated that TG19318, which is
one of PAM peptides, has affinity of KD=300 nM for rabbit IgG and
further that IgG contained in serum of a human, a bovine, a horse,
a pig, a mouse, a rat, a goat, or a sheep can be purified by
affinity chromatography using immobilized TG19318 (Non Patent
Literature 6).
[0010] Ehrlich et al. used a phage library displaying linear
peptides of 7 or 12 residues on filamentous bacteriophage M13 to
isolate a peptide having affinity for a pFc' fragment obtained by
pepsin digestion of humanized IgG (Non Patent Literature 7), as in
the method of Suzuki et al.
[0011] Krook et al. used a phage library displaying linear peptides
of 10-residue length on filamentous bacteriophage M13 to produce a
peptide having affinity for the Fc region of human IgG. They
confirmed by ELISA that this peptide had high affinity for IgG
derived from a human or a pig (Non Patent Literature 8).
[0012] Verdoliva et al. performed screening of a synthetic peptide
library represented by (Cys Xaa3)2 Lys Gly into which a branched
structure due to the Lys residue and circularization due to the Cys
residue are introduced, for mouse monoclonal IgG to produce peptide
FcRM having affinity for the vicinity of the hinge region. They
further reported construction of affinity chromatography on which
this FcRM was immobilized to purify mouse or human derived IgG (Non
Patent Literature 9).
[0013] Watanabe et al. used an artificial protein library including
10-residue microprotein chignolin and random amino acid sequences
(Patent Literature 3) for increasing the affinity of a linear
peptide, which shows low affinity for the Fc region of human IgG,
to improve the affinity by 40,600 times without having a cyclic
structure and produced a 54-residue polypeptide AF.p17 having a
high affinity of KD=1.6 nM (Patent Literature 4 and Non Patent
Literature 10).
[0014] Sakamoto et al. used a phage library displaying cyclic
peptides represented by Cys Xaa?-10 Cys on T7 bacteriophage to
produce a peptide having affinity for the Fc region of human IgG
(Non Patent Literature 11). The peptide produced by them differs
from the above-mentioned IgG affinity peptides produced so far in
that the peptide recognizes an Fc region forming a non-native
three-dimensional structure caused by acid treatment, not an Fc
region having a native three-dimensional structure. Ito et al.
disclosed that this peptide can be used to investigate the contents
of non-native three-dimensional structures generated by acid
treatment included in human antibody drugs, immunoglobulin
preparations, and IgG reagents (Patent Literature 5).
[0015] Watanabe et al. used an artificial protein library including
10-residue microprotein chignolin (Patent Literature 3) to produce
25-residue artificial protein AF.2A1 having affinity for the Fc
region of human IgG (Non Patent Literature 12). AF.2A1 had high
specific affinity for the Fc region forming a non-native
three-dimensional structure occurring by, for example, acid
treatment, heat treatment, or reducing agent treatment and strictly
distinguished between the native three-dimensional structure and
the non-native three-dimensional structure of the Fc region (Patent
Literature 4).
[0016] As described above, multiple IgG affinity peptides have been
developed, but the molecular diversity thereof is not sufficient.
This is because IgG is constituted as a hetero-tetramer composed of
heavy chains each constituted of four domains VH, CH1, CH2, and CH3
and light chains each constituted of two domains VL and CL and thus
has a complex structure constituted of six domains in total. In
implementation of, for example, detection, purification,
immobilization, analysis, or removal of antibodies or the like,
antibody affinity molecules having characteristics suitable for
respective use situations are necessary. Specifically, the antibody
affinity molecules needed are those having appropriate
characteristics in terms of, for example, the site of an antibody
or a protein including an antibody domain to which the molecule
binds, the degree of the specificity of molecular recognition, the
ability to distinguish differences not only in amino acid sequences
but also in changed three-dimensional structures, the degree of
strength of the affinity, the ability to control
binding/dissociation by, for example, a change in solution
conditions, the solubility and stability, and the possibility of
mass production.
[0017] Along with the expansion of the antibody drugs market,
further sophistication of analytical techniques and
separation/purification techniques targeting antibody molecules has
been highly desired.
[0018] With regard to the analytical techniques, as techniques
strongly desired for future advancement, particularly expected are
development in three areas: (1) an analytical technique on
molecular heterogeneity accompanying post-translational
modifications including glycosylation, (2) an analytical technique
on molecular heterogeneity accompanying a change in the
three-dimensional structure of an antibody, and (3) an analytical
technique on molecular heterogeneity accompanying formation of
associate/aggregate (Non Patent Literature 13). It has been
reported that antibody molecules form a non-native
three-dimensional structure, called alternatively folded state
(AFS), different from the usual native three-dimensional structure
by various physical or chemical stresses (Non Patent Literatures 14
and 15). Such a non-native three-dimensional structure not only
results in loss of activity of the antibody but also may cause
protein aggregation. As a result, not only a reduction in drug
efficacy but also risks that cause side effects due to induction of
immunogenicity are suggested (Non Patent Literature 16), and the
analytical technique on the non-native three-dimensional structures
of antibodies is required to develop as an indispensable technique
for quality control of antibody drugs (Non Patent Literature
17).
[0019] Examples of the analytical technique that can reveal the
molecular shape or three-dimensional structure of a protein include
X-ray crystal structure analysis, nuclear magnetic resonance,
electron microscope, analytical ultracentrifugation, isoelectric
focusing electrophoresis, dynamic light scattering, circular
dichroism spectrum, and liquid chromatography (Non Patent
Literature 17). Although the analytical techniques have respective
advantages such as analysis accuracy, high throughput of
measurement, and detection sensitivity, in general, analysis
accuracy and throughput are in a trade-off relationship, and no
spectroscopic and chromatographic methods satisfy both
requirements. For example, X-ray crystal structure analysis and
nuclear magnetic resonance, which can provide information on
three-dimensional structure with atomic-level precision, need
analysis time on the order of several months. In contrast, dynamic
light scattering and liquid chromatography, which can complete the
measurement in a few minutes, cannot detect a minute change in the
molecular structure and trace incorporation. Accordingly, it is
required to solve the problems related to compatibility between
analysis accuracy and throughput of the analytical techniques.
[0020] On the other hand, as an antibody separation/purification
technique, an affinity chromatography technique using a molecule
having specific affinity for an antibody as a binding ligand is
used. As the binding ligand for this application, natural proteins
derived from bacteria, such as protein A and protein G, or
artificially produced antibody affinity molecules are used.
Although it is possible to bind/collect antibodies by these
affinity molecules, most of the molecules have affinity for the
native three-dimensional structure or non-native three-dimensional
structure of the antibody Fc region (Patent Literatures 1 to 5 and
Non Patent Literatures 3 to 12), and cannot specifically
distinguish between the native three-dimensional structure and the
non-native three-dimensional structure of the CH1-CL domain, which
is the constant region of an antibody Fab region.
CITATION LIST
Patent Literature
[0021] Patent Literature 1: Japanese Unexamined Patent Application
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International Publication No. WO2001/045746 [0023] Patent
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[0025] Patent Literature 5: International Publication No.
WO2008/054030 [0026] Patent Literature 6: Japanese Unexamined
Patent Application Publication (Translation of PCT Application) No.
2011-517690
Non Patent Literature
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SUMMARY OF INVENTION
Technical Problem
[0065] It is an object of the present invention to provide a novel
polypeptide that has specific affinity for a protein partially
including a CH1-CL domain forming a non-native three-dimensional
structure among proteins including a CH1-CL domain of an antibody
such as IgG or a Fab region and can be suitably used in detection,
immobilization, or removal of the protein, to expand the molecular
diversity of an affinity polypeptide that can be used in industry,
such as antibody research, production, and quality control, and
thereby expand the diversity of detection, immobilization, or
removal of the protein.
Solution to Problem
[0066] The present inventors have diligently studied to solve the
above problems and as a result, have found that a short polypeptide
having a specific amino acid sequence pattern has specific affinity
for a CH1-CL domain forming a non-native three-dimensional
structure. The present invention has been accomplished based on
these findings. In the present specification, the terms "peptide",
"polypeptide", and "protein" are used interchangeably.
[0067] That is, the present invention encompasses the
followings:
[0068] [1] A polypeptide consisting of an amino acid sequence
represented by Formula 1:
TABLE-US-00001 (1) (SEQ ID NO: 1) P-Q-x-I-x-L-x-[IL]-[NT]-[YW]
(wherein x represents an amino acid residue, and brackets ([ ])
represent any one of the amino acid residues within the brackets)
or a polypeptide consisting of an amino acid sequence having
addition of one or several amino acid residues in the amino acid
sequence represented by Formula 1, wherein the polypeptide has
affinity for the CH1-CL domain of immunoglobulin G. The "several"
amino acid residues to be added mean, for example, 1 to 20,
preferably 1 to 10, and more preferably 1 to 5 amino acid residues,
unless otherwise specified.
[0069] In above [1], the polypeptide may be a polypeptide
consisting of an amino acid sequence represented by
P-Q-[DNEQHFYW]-1-[RKHSTY]-L-[GAVLIPSTY]-[IL]-[NT]-[YW] (wherein
brackets represent any one of the amino acid residues within the
brackets) or a polypeptide consisting of an amino acid sequence
having addition of one or several amino acid residues in the amino
acid sequence represented by the formula, wherein the polypeptide
has affinity for a CH1-CL domain of immunoglobulin G.
[0070] In above [1], the polypeptide may be a polypeptide
consisting of an amino acid sequence represented by
P-Q-[EW]-I-[RT]-L-[IT]-[IL]-[NT]-[YW] (wherein brackets represent
any one of the amino acid residues within the brackets) according
to Formula 1 or a polypeptide consisting of an amino acid sequence
having addition of one or several amino acid residues in the amino
acid sequence represented by the formula, wherein the polypeptide
has affinity for a CH1-CL domain of immunoglobulin G.
[0071] [2] The polypeptide according to above [1], wherein the
polypeptide is a polypeptide consisting of an amino acid sequence
represented by SEQ ID NO: 2 or 3:
TABLE-US-00002 (SEQ ID NO: 2) PQEIRLILNW, (SEQ ID NO: 3)
PQWITLTITY,
[0072] or a polypeptide consisting of an amino acid sequence having
addition, deletion, substitution, or insertion of one amino acid
residue in the amino acid sequence represented by SEQ ID NO: 2 or 3
by, wherein the polypeptide has affinity for a CH1-CL domain of
immunoglobulin G. The substitution of the amino acid residue is
preferably conservative amino acid substitution.
[0073] [3] A polypeptide consisting of an amino acid sequence
represented by Formula 2:
TABLE-US-00003 (2) (SEQ ID NO: 4)
Y-D-P-E-T-G-T-W-P-Q-x-I-x-L-x-[IL]-[NT]-[YW]
[0074] (wherein x represents an amino acid residue, and brackets
represent any one of the amino acid residues within the brackets)
or a polypeptide consisting of an amino acid sequence having
addition of one or several amino acid residues in the amino acid
sequence represented by Formula 2, wherein the polypeptide has
affinity for a CH1-CL domain of immunoglobulin G.
[0075] The polypeptide according to above [3] may be a polypeptide
consisting of an amino acid sequence represented by
Y-D-P-E-T-G-T-W-P-Q-[DNEQHFYW]-I-[RKHSTY]-L-[GAVLIPSTY]-[IL]-[NT]-[YW]
(wherein brackets represent any one of the amino acid residues
within the brackets) or a polypeptide consisting of an amino acid
sequence having addition of one or several amino acid residues in
the amino acid sequence the formula, wherein the polypeptide has
affinity for a CH1-CL domain of immunoglobulin G.
[0076] In above [3], the polypeptide may be a polypeptide
consisting of an amino acid sequence represented by
Y-D-P-E-T-G-T-W-P-Q-[EW]-1-[RT]-L-[IT]-[IL]-[NT]-[YW] (wherein
brackets represent any one of the amino acid residues within the
brackets) or a polypeptide consisting of an amino acid sequence
having addition of one or several amino acid residues in the amino
acid sequence represented by the formula, wherein the polypeptide
has affinity for a CH1-CL domain of immunoglobulin G.
[0077] [4] The polypeptide according to [3], wherein the
polypeptide is a polypeptide consisting of an amino acid sequence
represented by any one of SEQ ID NOs: 5, 6, and 36 to 41:
TABLE-US-00004 (SEQ ID NO: 5) YDPETGTWPQEIRLILNW (SEQ ID NO: 6)
YDPETGTWPQWITLTITY (SEQ ID NO: 36) HNFTLPLWMYYDPETGTWPQEIRLILNW
(SEQ ID NO: 37) RFPLMFGPSWYDPETGTWPQEIRLILNW (SEQ ID NO: 38)
RFYVLLDSSWYDPETGTWPQEIRLILNW (SEQ ID NO: 39)
VSKFYPLWTRYDPETGTWPQEIRLILNW (SEQ ID NO: 40)
VFLVLMGPEFYDPETGTWPQEIRLILNW (SEQ ID NO: 41)
FLLFCPRSLCYDPETGTWPQEIRLILNW
[0078] or a polypeptide consisting of an amino acid sequence having
addition, deletion, substitution, or insertion of one or two amino
acid residues in the amino acid sequence represented by any one of
SEQ ID NOs: 5, 6, and 36 to 41, wherein the polypeptide has
affinity for a CH1-CL domain of immunoglobulin G. The substitution
of the amino acid residue(s) is preferably conservative amino acid
substitution.
[0079] [5] A polypeptide consisting of an amino acid sequence
represented by Formula 3:
TABLE-US-00005 (SEQ ID NO: 7)
P-N-S-G-G-G-G-S-Y-D-P-E-T-G-T-W-P-Q-x-I- x-L-x-[IL]-[NT]-[YW]
(wherein x represents an amino acid residue, and brackets represent
any one of the amino acid residues within the brackets) or a
polypeptide consisting of an amino acid sequence having one or
several amino acid residues in the amino acid sequence represented
by Formula 3, wherein the polypeptide has affinity for a CH1-CL
domain of immunoglobulin G.
[0080] In above [5], the polypeptide may be a polypeptide
consisting of an amino acid sequence represented by
P--N-S-G-G-G-G-S-Y-D-P-E-T-G-T-W-P-Q-[DNEQHFYW]-1-[RKHSTY]-L-[GAVLIPSTY]--
[IL]-[NT]-[YW] (wherein brackets represent any one of the amino
acid residues within the brackets) or a polypeptide consisting of
an amino acid sequence having addition of one or several amino acid
residues in the amino acid sequence represented by the formula,
wherein the polypeptide has affinity for a CH1-CL domain of
immunoglobulin G.
[0081] In above [5], the polypeptide may be a polypeptide
consisting of an amino acid sequence represented by
P--N-S-G-G-G-G-S-Y-D-P-E-T-G-T-W-P-Q-[EW]-1-[RT]-L-[IT]-[IL]-[NT]-[YW]
(wherein brackets represent any one of the amino acid residues
within the brackets) or a polypeptide consisting of an amino acid
sequence having addition of one or several amino acid residues in
the amino acid sequence represented by the formula, wherein the
polypeptide has affinity for a CH1-CL domain of immunoglobulin G.
The meaning of "several" can be the same as that in above [7] (see
the explanation below).
[0082] [6] The polypeptide according to [5], wherein the
polypeptide is a polypeptide consisting of an amino acid sequence
represented by any one of SEQ ID NOs: 8 to 9:
TABLE-US-00006 (SEQ ID NO: 8) PNSGGGGSYDPETGTWPQEIRLILNW (SEQ ID
NO: 9) PNSGGGGSYDPETGTWPQWITLTITY (SEQ ID NO: 10)
PNSGGGGSYDPETGTWAQEIRLILNW (SEQ ID NO: 11)
PNSGGGGSYDPETGTWPAEIRLILNW (SEQ ID NO: 12)
PNSGGGGSYDPETGTWPQEIRLIANW
[0083] or a polypeptide consisting of an amino acid sequence having
addition, deletion, substitution, or insertion of one to three
amino acid residues in the amino acid sequence represented by any
one of SEQ ID NOs: 8 to 12, wherein the polypeptide has affinity
for a CH1-CL domain of immunoglobulin G. The substitution of the
amino acid residue(s) is preferably conservative amino acid
substitution.
[0084] [7] A tandem polypeptide having the polypeptide according to
any one of [1] to [6] with a second polypeptide at the
amino-terminus, the carboxyl-terminus, or both termini thereof,
wherein the tandem polypeptide has affinity for a CH1-CL domain of
immunoglobulin G.
[0085] [8] A fusion protein having a protein bound to the
amino-terminus, the carboxy-terminus, or both termini of the
polypeptide according to any one of [1] to [6], wherein the fusion
protein has affinity for a CH1-CL domain of immunoglobulin G.
[0086] [9] The protein according to [13], consisting of an amino
acid sequence represented by any one of SEQ ID NOs: 13 to 15 and 42
to 46:
TABLE-US-00007 (SEQ ID NO: 13)
MSDKIIHLTDDSFDTDVLKADGAILVDFWAEWCGPCKMIAPILDEIAD
EYQGKLTVAKLNIDQNPGTAPKYGIRGIPTLLLFKNGEVAATKVGALS
KGQLKEFLDANLAGSGSGHTSGGGGSNNNPPTPTPSSGSGHHHHHHSA
ALEVLFQGPGYQDPNSGGGGSYDPETGTWPQAQKKEIQT (SEQ ID NO: 14)
MSDKIIHLTDDSFDTDVLKADGAILVDFWAEWCGPCKMIAPILDEIAD
EYQGKLTVAKLNIDQNPGTAPKYGIRGIPTLLLFKNGEVAATKVGALS
KGQLKEFLDANLAGSGSGHTSGGGGSNNNPPTPTPSSGSGHHHHHHSA
ALEVLFQGPGYQDPNSGGGGSYDPETGTWPQEIRLILNW (SEQ ID NO: 15)
MSDKIIHLTDDSFDTDVLKADGAILVDFWAEWCGPCKMIAPILDEIAD
EYQGKLTVAKLNIDQNPGTAPKYGIRGIPTLLLFKNGEVAATKVGALS
KGQLKEFLDANLAGSGSGHTSGGGGSNNNPPTPTPSSGSGHHHHHHSA
ALEVLFQGPGYQDPNSGGGGSYDPETGTWPQWITLTITY (SEQ ID NO: 42)
MSDKIIHLTDDSFDTDVLKADGAILVDFWAEWCGPCKMIAPILDEIAD
EYQGKLTVAKLNIDQNPGTAPKYGIRGIPTLLLFKNGEVAATKVGALS
KGQLKEFLDANLAGSGSGHTSGGGGSNNNPPTPTPSSGSGHHHHHHSA
ALEVLFQGPGYQDPNSGGGGSHNFTLPLWMYYDPETGTWPQEIRLILN W (SEQ ID NO: 43)
MSDKIIHLTDDSFDTDVLKADGAILVDFWAEWCGPCKMIAPILDEIAD
EYQGKLTVAKLNIDQNPGTAPKYGIRGIPTLLLFKNGEVAATKVGALS
KGQLKEFLDANLAGSGSGHTSGGGGSNNNPPTPTPSSGSGHHHHHHSA
ALEVLFQGPGYQDPNSGGGGSRFPLMFGPSWYDPETGTWPQEIRLILN W (SEQ ID NO: 44)
MSDKIIHLTDDSFDTDVLKADGAILVDFWAEWCGPCKMIAPILDEIAD
EYQGKLTVAKLNIDQNPGTAPKYGIRGIPTLLLFKNGEVAATKVGALS
KGQLKEFLDANLAGSGSGHTSGGGGSNNNPPTPTPSSGSGHHHHHHSA
ALEVLFQGPGYQDPNSGGGGSRFYVLLDSSWYDPETGTWPQEIRLILN W (SEQ ID NO: 45)
MSDKIIHLTDDSFDTDVLKADGAILVDFWAEWCGPCKMIAPILDEIAD
EYQGKLTVAKLNIDQNPGTAPKYGIRGIPTLLLFKNGEVAATKVGALS
KGQLKEFLDANLAGSGSGHTSGGGGSNNNPPTPTPSSGSGHHHHHHSA
ALEVLFQGPGYQDPNSGGGGSVSKFYPLWTRYDPETGTWPQEIRLILN W (SEQ ID NO: 46)
MSDKIIHLTDDSFDTDVLKADGAILVDFWAEWCGPCKMIAPILDEIAD
EYQGKLTVAKLNIDQNPGTAPKYGIRGIPTLLLFKNGEVAATKVGALS
KGQLKEFLDANLAGSGSGHTSGGGGSNNNPPTPTPSSGSGHHHHHHSA
ALEVLFQGPGYQDPNSGGGGSVFLVLMGPEFYDPETGTWPQEIRLILN W.
[0087] [10] A nucleic acid encoding the polypeptide according to
any one of [1] to [7] or the protein according to [8] or [9].
[0088] [11] The nucleic acid according to [10], consisting of a
nucleotide sequence represented by any one of SEQ ID NOs: 16 to 18
and 47 to 51:
TABLE-US-00008 (SEQ ID NO: 16)
ATGAGCGATAAAATTATTCACCTGACTGACGACAGTTTTGACACGGAT
GTACTCAAAGCGGACGGGGCGATCCTCGTCGATTTCTGGGCAGAGTGG
TGCGGTCCGTGCAAAATGATCGCCCCGATTCTGGATGAAATCGCTGAC
GAATATCAGGGCAAACTGACCGTTGCAAAACTGAACATCGATCAAAAC
CCTGGCACTGCGCCGAAATATGGCATCCGTGGTATCCCGACTCTGCTG
CTGTTCAAAAACGGTGAAGTGGCGGCAACCAAAGTGGGTGCACTGTCT
AAAGGTCAGTTGAAAGAGTTCCTCGACGCTAACCTGGCCGGTTCTGGT
TCTGGCCATACTAGTGGTGGTGGCGGTTCTAATAACAATCCTCCTACT
CCTACTCCATCTAGTGGTTCTGGTCATCACCATCACCATCACTCCGCG
GCTCTTGAAGTCCTCTTTCAGGGACCCGGGTACCAGGATCCGAATTCG
GGAGGAGGGGGATCATACGACCCCGAGACGGGCACGTGGCCACAAGCA
CAGAAAAAAGAGATACAAACA (SEQ ID NO: 17)
ATGAGCGATAAAATTATTCACCTGACTGACGACAGTTTTGACACGGAT
GTACTCAAAGCGGACGGGGCGATCCTCGTCGATTTCTGGGCAGAGTGG
TGCGGTCCGTGCAAAATGATCGCCCCGATTCTGGATGAAATCGCTGAC
GAATATCAGGGCAAACTGACCGTTGCAAAACTGAACATCGATCAAAAC
CCTGGCACTGCGCCGAAATATGGCATCCGTGGTATCCCGACTCTGCTG
CTGTTCAAAAACGGTGAAGTGGCGGCAACCAAAGTGGGTGCACTGTCT
AAAGGTCAGTTGAAAGAGTTCCTCGACGCTAACCTGGCCGGTTCTGGT
TCTGGCCATACTAGTGGTGGTGGCGGTTCTAATAACAATCCTCCTACT
CCTACTCCATCTAGTGGTTCTGGTCATCACCATCACCATCACTCCGCG
GCTCTTGAAGTCCTCTTTCAGGGACCCGGGTACCAGGATCCGAATTCG
GGAGGAGGGGGATCATACGACCCCGAGACGGGCACGTGGCCACAGGAA
ATTAGACTAATACTTAATTGG (SEQ ID NO: 18)
ATGAGCGATAAAATTATTCACCTGACTGACGACAGTTTTGACACGGAT
GTACTCAAAGCGGACGGGGCGATCCTCGTCGATTTCTGGGCAGAGTGG
TGCGGTCCGTGCAAAATGATCGCCCCGATTCTGGATGAAATCGCTGAC
GAATATCAGGGCAAACTGACCGTTGCAAAACTGAACATCGATCAAAAC
CCTGGCACTGCGCCGAAATATGGCATCCGTGGTATCCCGACTCTGCTG
CTGTTCAAAAACGGTGAAGTGGCGGCAACCAAAGTGGGTGCACTGTCT
AAAGGTCAGTTGAAAGAGTTCCTCGACGCTAACCTGGCCGGTTCTGGT
TCTGGCCATACTAGTGGTGGTGGCGGTTCTAATAACAATCCTCCTACT
CCTACTCCATCTAGTGGTTCTGGTCATCACCATCACCATCACTCCGCG
GCTCTTGAAGTCCTCTTTCAGGGACCCGGGTACCAGGATCCGAATTCG
GGAGGAGGGGGATCATACGACCCCGAGACGGGCACGTGGCCGCAGTGG
ATAACTCTTACGATAACGTAT (SEQ ID NO: 47)
ATGAGCGATAAAATTATTCACCTGACTGACGACAGTTTTGACACGGAT
GTACTCAAAGCGGACGGGGCGATCCTCGTCGATTTCTGGGCAGAGTGG
TGCGGTCCGTGCAAAATGATCGCCCCGATTCTGGATGAAATCGCTGAC
GAATATCAGGGCAAACTGACCGTTGCAAAACTGAACATCGATCAAAAC
CCTGGCACTGCGCCGAAATATGGCATCCGTGGTATCCCGACTCTGCTG
CTGTTCAAAAACGGTGAAGTGGCGGCAACCAAAGTGGGTGCACTGTCT
AAAGGTCAGTTGAAAGAGTTCCTCGACGCTAACCTGGCCGGTTCTGGT
TCTGGCCATACTAGTGGTGGTGGCGGTTCTAATAACAATCCTCCTACT
CCTACTCCATCTAGTGGTTCTGGTCATCACCATCACCATCACTCCGCG
GCTCTTGAAGTCCTCTTTCAGGGACCCGGGTACCAGGATCCGAATTCG
GGAGGAGGGGGATCACATAATTTTACTCTTCCTCTGTGGATGTATTAC
GACCCCGAGACGGGCACGTGGCCGCAGGAAATTCGCCTGATTCTGAAC TGG (SEQ ID NO:
48) ATGAGCGATAAAATTATTCACCTGACTGACGACAGTTTTGACACGGAT
GTACTCAAAGCGGACGGGGCGATCCTCGTCGATTTCTGGGCAGAGTGG
TGCGGTCCGTGCAAAATGATCGCCCCGATTCTGGATGAAATCGCTGAC
GAATATCAGGGCAAACTGACCGTTGCAAAACTGAACATCGATCAAAAC
CCTGGCACTGCGCCGAAATATGGCATCCGTGGTATCCCGACTCTGCTG
CTGTTCAAAAACGGTGAAGTGGCGGCAACCAAAGTGGGTGCACTGTCT
AAAGGTCAGTTGAAAGAGTTCCTCGACGCTAACCTGGCCGGTTCTGGT
TCTGGCCATACTAGTGGTGGTGGCGGTTCTAATAACAATCCTCCTACT
CCTACTCCATCTAGTGGTTCTGGTCATCACCATCACCATCACTCCGCG
GCTCTTGAAGTCCTCTTTCAGGGACCCGGGTACCAGGATCCGAATTCG
GGAGGAGGGGGATCACGTTTTCCGTTGATGTTTGGGCCGTCTTGGTAC
GACCCCGAGACGGGCACGTGGCCGCAGGAAATTCGCCTGATTCTGAAC TGG (SEQ ID NO:
49) ATGAGCGATAAAATTATTCACCTGACTGACGACAGTTTTGACACGGAT
GTACTCAAAGCGGACGGGGCGATCCTCGTCGATTTCTGGGCAGAGTGG
TGCGGTCCGTGCAAAATGATCGCCCCGATTCTGGATGAAATCGCTGAC
GAATATCAGGGCAAACTGACCGTTGCAAAACTGAACATCGATCAAAAC
CCTGGCACTGCGCCGAAATATGGCATCCGTGGTATCCCGACTCTGCTG
CTGTTCAAAAACGGTGAAGTGGCGGCAACCAAAGTGGGTGCACTGTCT
AAAGGTCAGTTGAAAGAGTTCCTCGACGCTAACCTGGCCGGTTCTGGT
TCTGGCCATACTAGTGGTGGTGGCGGTTCTAATAACAATCCTCCTACT
CCTACTCCATCTAGTGGTTCTGGTCATCACCATCACCATCACTCCGCG
GCTCTTGAAGTCCTCTTTCAGGGACCCGGGTACCAGGATCCGAATTCG
GGAGGAGGGGGATCACGGTTTTATGTTCTGCTGGATTCTTCTTGGTAC
GACCCCGAGACGGGCACGTGGCCGCAGGAAATTCGCCTGATTCTGAAC TGG (SEQ ID NO:
50) ATGAGCGATAAAATTATTCACCTGACTGACGACAGTTTTGACACGGAT
GTACTCAAAGCGGACGGGGCGATCCTCGTCGATTTCTGGGCAGAGTGG
TGCGGTCCGTGCAAAATGATCGCCCCGATTCTGGATGAAATCGCTGAC
GAATATCAGGGCAAACTGACCGTTGCAAAACTGAACATCGATCAAAAC
CCTGGCACTGCGCCGAAATATGGCATCCGTGGTATCCCGACTCTGCTG
CTGTTCAAAAACGGTGAAGTGGCGGCAACCAAAGTGGGTGCACTGTCT
AAAGGTCAGTTGAAAGAGTTCCTCGACGCTAACCTGGCCGGTTCTGGT
TCTGGCCATACTAGTGGTGGTGGCGGTTCTAATAACAATCCTCCTACT
CCTACTCCATCTAGTGGTTCTGGTCATCACCATCACCATCACTCCGCG
GCTCTTGAAGTCCTCTTTCAGGGACCCGGGTACCAGGATCCGAATTCG
GGAGGAGGGGGATCAGTGAGTAAGTTTTATCCGCTGTGGACGCGGTAC
GACCCCGAGACGGGCACGTGGCCGCAGGAAATTCGCCTGATTCTGAAC TGG (SEQ ID NO:
51) ATGAGCGATAAAATTATTCACCTGACTGACGACAGTTTTGACACGGAT
GTACTCAAAGCGGACGGGGCGATCCTCGTCGATTTCTGGGCAGAGTGG
TGCGGTCCGTGCAAAATGATCGCCCCGATTCTGGATGAAATCGCTGAC
GAATATCAGGGCAAACTGACCGTTGCAAAACTGAACATCGATCAAAAC
CCTGGCACTGCGCCGAAATATGGCATCCGTGGTATCCCGACTCTGCTG
CTGTTCAAAAACGGTGAAGTGGCGGCAACCAAAGTGGGTGCACTGTCT
AAAGGTCAGTTGAAAGAGTTCCTCGACGCTAACCTGGCCGGTTCTGGT
TCTGGCCATACTAGTGGTGGTGGCGGTTCTAATAACAATCCTCCTACT
CCTACTCCATCTAGTGGTTCTGGTCATCACCATCACCATCACTCCGCG
GCTCTTGAAGTCCTCTTTCAGGGACCCGGGTACCAGGATCCGAATTCG
GGAGGAGGGGGATCAGTGTTTCTTGTTTTGATGGGGCCTGAGTTTTAC
GACCCCGAGACGGGCACGTGGCCGCAGGAAATTCGCCTGATTCTGAAC TGG.
[0089] [12] A recombinant vector comprising the nucleic acid
according to [10] or [11].
[0090] [13] A transformant into which the recombinant vector
according to [12] is introduced.
[0091] [14] A recombinant phage or a recombinant virus comprising
the nucleic acid according to [10] or [11].
[0092] [15] A modified polypeptide or a modified protein having the
polypeptide according to any one of [1] to [7] or the protein
according to [8] bound to an organic compound, or an inorganic
compound, or both an organic compound and an inorganic compound,
wherein the modified polypeptides or the modified protein has
affinity for a CH1-CL domain of immunoglobulin G.
[0093] [16] An immobilized polypeptide or an immobilized protein,
where the polypeptide according to any one of [1] to [7], the
protein according to [8] or [9], or the polypeptide or the protein
according to [15] is immobilized on a water-insoluble solid-phase
support.
[0094] [17] A kit for detecting, purifying, immobilizing, or
removing a protein partially including a CH1-CL domain of
immunoglobulin G, the CH1-CL domain forming a non-native
three-dimensional structure, the kit comprising at least one
selected from the group consisting of the polypeptide according to
any one of [1] to [7], the protein according to [8] or [9], the
nucleic acid according to [10] or [11], the recombinant vector
according to [12], the transformant according to [13], the
recombinant phage or the recombinant virus according to [14], the
polypeptide or the protein according to [15], and the immobilized
polypeptide or the immobilized protein according to [16].
[0095] [18] A method for detecting a protein partially including a
CH1-CL domain of immunoglobulin G, the CH1-CL domain forming a
non-native three-dimensional structure, the method comprising:
[0096] (1) contacting a test sample to be contaminated with the
protein including the CH1-CL domain, with the polypeptide according
to any one of [1] to [7], the protein according to [8] or [9], the
transformant according to [13], the recombinant phage or the
recombinant virus according to [14], the polypeptide or the protein
according to [15], or the immobilized polypeptide or the
immobilized protein according to [16]; and
[0097] (2) determining whether or not a bond is formed between the
protein including the CH1-CL domain and the polypeptide, the
protein, the transformant, the recombinant phage or the recombinant
virus, or the immobilized polypeptide or the immobilized
protein.
[0098] [19] A method for purifying a protein partially including a
CH1-CL domain of immunoglobulin G, the CH1-CL domain forming a
non-native three-dimensional structure, the method comprising:
[0099] (1) contacting a sample containing the protein including the
CH1-CL domain with the polypeptide according to any one of [1] to
[7], the protein according to [8] or [9], the transformant
according to [13], the recombinant phage or the recombinant virus
according to [14], the polypeptide or the protein according to
[15], or the immobilized polypeptide or the immobilized protein
according to [16] to bind the protein including the CH1-CL domain
to the polypeptide, the protein, the transformant, the recombinant
phage or the recombinant virus, or the immobilized polypeptide or
the immobilized protein; and
[0100] (2) collecting the protein including the CH1-CL domain bound
to the polypeptide, the protein, the transformant, the recombinant
phage or the recombinant virus, or the immobilized polypeptide or
the immobilized protein from the sample.
[0101] [20] A method for removing a protein partially including a
CH1-CL domain of immunoglobulin G, the CH1-CL domain forming a
non-native three-dimensional structure, the method comprising:
[0102] (1) contacting a sample containing the protein including the
CH1-CL domain with the polypeptide according to any one of [1] to
[7], the protein according to [8] or [9], the transformant
according to [13], the recombinant phage or the recombinant virus
according to [14], the polypeptide or the protein according to
[15], or the immobilized polypeptide or the immobilized protein
according to [16] to bind the protein including the CH1-CL domain
to the polypeptide, the protein, the transformant, the recombinant
phage or the recombinant virus, or the immobilized polypeptide or
the immobilized protein; and
[0103] (2) removing the protein including the CH1-CL domain bound
to the polypeptide, the protein, the transformant, the recombinant
phage or the recombinant virus, or the immobilized polypeptide or
the immobilized protein from the sample.
[0104] In substitution of an amino acid residue, it is desirable to
replace the amino acid residue with another amino acid conserving
the properties of the amino acid side chain. For example, based on
the properties of amino acid side chains, the following
classification has been established:
[0105] Hydrophobic amino acids (A, I, L, M, F, P, W, Y, and V),
[0106] Hydrophilic amino acids (R, D, N, C, E, Q, G, H, K, S, and
T),
[0107] Amino acids having aliphatic side chains (G, A, V, L, I, and
P),
[0108] Amino acids having hydroxyl group-containing side chains (S,
T, and Y),
[0109] Amino acids having sulfur atom-containing side chains (C and
M),
[0110] Amino acids having carboxylic acid and amide-containing side
chains (D, N, E, and Q),
[0111] Amino acids having base-containing side chains (R, K, and
H), and
[0112] Amino acids having aromatic-containing side chains (H, F, Y,
and W), (Any letter in parentheses represents an amino acid shown
in one-letter notation).
[0113] It is already known that a polypeptide having an amino acid
sequence modified by deletion, addition, and/or substitution of one
or several amino acid residues in the amino acid sequence with
other amino acids maintains the biological activity thereof (Mark,
D. F. et al., Proc. Natl. Acad. Sci. USA, (1984), 81, 5662-5666;
Zoller, M. J. and Smith, M., Nucleic Acids Research, (1982), 10,
6487-6500; Wang, A. et al., Science, 224, 1431-1433;
Dalbadie-McFarland, G. et al., Proc. Natl. Acad. Sci. USA, (1982),
79, 6409-6413). That is, it is generally said that in the amino
acid sequence constituting a certain polypeptide, amino acids
classified into the same group are highly likely to maintain the
activity of the polypeptide when substituted with each other. In
the present invention, the substitution between amino acids of the
same group in the above-mentioned amino acid groups is referred to
as "conservative substitution" or "conservative amino acid
substitution".
Advantageous Effects of Invention
[0114] The polypeptide of the present invention has specific
affinity for a protein partially including a CH1-CL domain forming
a non-native three-dimensional structure among proteins including a
CH1-CL domain of an antibody such as IgG or a Fab region thereof.
As a result, it is possible to distinguish between the non-native
three-dimensional structure and the native three-dimensional
structure of a CH1-CL domain. Alternatively, it is possible to
detect or immobilize a protein partially including a CH1-CL domain
forming a non-native three-dimensional structure by using the
polypeptide of the present invention.
[0115] In addition, AF.ab9 (SEQ ID NO: 8), a polypeptide including
the amino acid sequence represented by SEQ ID NO: 1 as a common
sequence, can specifically distinguish between a Fab region
partially including a CH1-CL domain forming a non-native
three-dimensional structure and a Fab region not including the
CH1-CL domain, and therefore can detect a change in the
three-dimensional structure specific to the CH1-CL domain of
IgG.
[0116] Furthermore, AF.ab9 (SEQ ID NO: 8), a polypeptide including
the amino acid sequence represented by SEQ ID NO: 1 as a common
sequence, changes the binding response to IgG treated with acid
buffer solutions depending on the degrees of acidity of the buffer
solutions, and therefore can detect the degree of change in the
three-dimensional structure occurring depending on the degree of
physical or chemical stress during manufacturing or storing the
protein partially including a CH1-CL domain, such as IgG or a Fab
region.
BRIEF DESCRIPTION OF DRAWINGS
[0117] FIG. 1 shows the results of verification of the purity of a
purified CH1-CL domain by sodium dodecyl sulfate (SDS)
polyacrylamide gel electrophoresis under nonreducing
conditions.
[0118] FIG. 2-1 shows the results of evaluation, by surface plasmon
resonance, of affinity between each of 32 clones of fusion proteins
(5 and 2.5 .mu.M) including an affinity polypeptide prepared as
thioredoxin fusion protein and a CH1-CL domain forming a non-native
three-dimensional structure and immobilized on a sensor chip. The
vertical axis of each graph represents the magnitude (resonance
unit) of the detection value, which reflects the weight of the
molecules bonded to the sensor chip. The magnitude of the detection
value depends on a plurality of measurement parameters such as the
concentration and the flow rate of the specimen, but the magnitudes
of the detection values when measured under the same conditions
roughly correspond to the degrees of affinity of the specimens.
(Incidentally, academically correct evaluation is actually possible
by fitting a resulting experimental curve with a theoretical curve
to calculate and compare, for example, the equilibrium dissociation
constant, dissociation rate constant, and binding rate constants.
The same applies to FIGS. 3 to 7.) The unit is the same between the
graphs, and the same value means the same magnitude.
[0119] FIG. 2-2 is the continuation of FIG. 2-1.
[0120] FIG. 3 shows (A) the results of evaluation, by surface
plasmon resonance, of affinity between IgG (2, 1, 0.5, 0.25, and
0.125 .mu.M) stored under neutral conditions and AF.ab9 immobilized
on a sensor chip; (B) the results of evaluation, by surface plasmon
resonance, of affinity between IgG (2, 1, 0.5, 0.25, and 0.125
.mu.M) treated with an acid buffer solution of pH 2.0 and AF.ab9
immobilized on a sensor chip; (C) the results of evaluation, by
surface plasmon resonance, of affinity between Fab region (2, 1,
0.5, 0.25, and 0.125 .mu.M) stored under neutral conditions and
AF.ab9 immobilized on a sensor chip; (D) the results of evaluation,
by surface plasmon resonance, of affinity between Fab region (2, 1,
0.5, 0.25, and 0.125 .mu.M) treated with an acid buffer solution of
pH 2.0 and AF.ab9 immobilized on a sensor chip; (E) the results of
evaluation, by surface plasmon resonance, of affinity between Fc
region (2, 1, 0.5, 0.25, and 0.125 .mu.M) stored under neutral
conditions and AF.ab9 immobilized on a sensor chip; and (F) the
results of evaluation, by surface plasmon resonance, of affinity
between Fc region (2, 1, 0.5, 0.25, and 0.125 .mu.M) treated with
an acid buffer solution of pH 2.0 and AF.ab9 immobilized on a
sensor chip. The vertical axis of each graph represents the
magnitude (resonance unit) of the detection value, which reflects
the weight of the molecules bonded to the sensor chip. The
magnitude of the detection value depends on a plurality of
measurement parameters such as the concentration and the flow rate
of the specimen, but the magnitudes of the detection values when
measured under the same conditions roughly correspond to the
degrees of affinity of the specimens. The unit is the same between
the graphs, and the same value means the same magnitude.
[0121] FIG. 4 shows (A) the results of evaluation, by surface
plasmon resonance, of affinity between IgG (2, 1, 0.5, 0.25, and
0.125 .mu.M) treated with an acid buffer solution of pH 4.0 and
AF.ab9 immobilized on a sensor chip; (B) the results of evaluation,
by surface plasmon resonance, of affinity between IgG (2, 1, 0.5,
0.25, and 0.125 .mu.M) treated with an acid buffer solution of pH
3.0 and AF.ab9 immobilized on a sensor chip; and (C) the results of
evaluation, by surface plasmon resonance, of affinity between IgG
(2, 1, 0.5, 0.25, and 0.125 .mu.M) treated with an acid buffer
solution of pH 2.0 and AF.ab9 immobilized on a sensor chip. The
vertical axis of each graph represents the magnitude (resonance
unit) of the detection value, which reflects the weight of the
molecules bonded to the sensor chip. The magnitude of the detection
value depends on a plurality of measurement parameters such as the
concentration and the flow rate of the specimen, but the magnitudes
of the detection values when measured under the same conditions
roughly correspond to the degrees of affinity of the specimens. The
unit is the same between the graphs, and the same value means the
same magnitude.
[0122] FIG. 5 shows (A) the results of evaluation, by surface
plasmon resonance, of affinity between AF.ab9 (4, 2, and 1 .mu.M)
and a CH1-CL domain forming a non-native three-dimensional
structure and immobilized on a sensor chip; (B) the results of
evaluation, by surface plasmon resonance, of affinity between
AF.ab9 arm (4, 2, and 1 .mu.M) and a CH1-CL domain forming a
non-native three-dimensional structure and immobilized on a sensor
chip; and (C) the results of evaluation, by surface plasmon
resonance, of affinity between AF.ab9 body (4, 2, and 1 .mu.M) and
a CH1-CL domain forming a non-native three-dimensional structure
and immobilized on a sensor chip. The vertical axis of each graph
represents the magnitude (resonance unit) of the detection value,
which reflects the weight of the molecules bonded to the sensor
chip. The magnitude of the detection value depends on a plurality
of measurement parameters such as the concentration and the flow
rate of the specimen, but the magnitudes of the detection values
when measured under the same conditions roughly correspond to the
degrees of affinity of the specimens. The unit is the same between
the graphs, and the same value means the same magnitude.
[0123] FIG. 6 shows (A) the results of evaluation, by surface
plasmon resonance, of affinity between AF.ab9 (50, 25, 12.5, 6.3,
3.2, and 1.6 .mu.M) and a CH1-CL domain forming a non-native
three-dimensional structure and immobilized on a sensor chip; and
(B) the results of evaluation, by surface plasmon resonance, of
affinity between AF.ab31 (50, 25, 12.5, 6.3, 3.2, and 1.6 .mu.M)
and a CH1-CL domain forming a non-native three-dimensional
structure and immobilized on a sensor chip. The vertical axis of
each graph represents the magnitude (resonance unit) of the
detection value, which reflects the weight of the molecules bonded
to the sensor chip. The magnitude of the detection value depends on
a plurality of measurement parameters such as the concentration and
the flow rate of the specimen, but the magnitudes of the detection
values when measured under the same conditions roughly correspond
to the degrees of affinity of the specimens. The unit is the same
between the graphs, and the same value means the same
magnitude.
[0124] FIG. 7 shows (A) the results of evaluation, by surface
plasmon resonance, of affinity between AF.ab9 (64, 32, 16, 8, 4,
and 2 .mu.M) and a CH1-CL domain forming a non-native
three-dimensional structure and immobilized on a sensor chip; (B)
the results of evaluation, by surface plasmon resonance, of
affinity between AF.ab9 P17A (64, 32, 16, 8, 4, and 2 .mu.M) and a
CH1-CL domain forming a non-native three-dimensional structure and
immobilized on a sensor chip; (C) the results of evaluation, by
surface plasmon resonance, of affinity between AF.ab9 Q18A (64, 32,
16, 8, 4, and 2 .mu.M) and a CH1-CL domain forming a non-native
three-dimensional structure and immobilized on a sensor chip; and
(D) the results of evaluation, by surface plasmon resonance, of
affinity between AF.ab9 L24A (64, 32, 16, 8, 4, and 2 .mu.M) and a
CH1-CL domain forming a non-native three-dimensional structure and
immobilized on a sensor chip. The vertical axis of each graph
represents the magnitude (resonance unit) of the detection value,
which reflects the weight of the molecules bonded to the sensor
chip. The magnitude of the detection value depends on a plurality
of measurement parameters such as the concentration and the flow
rate of the specimen, but the magnitudes of the detection values
when measured under the same conditions roughly correspond to the
degrees of affinity of the specimens. The unit is the same between
the graphs, and the same value means the same magnitude.
[0125] FIG. 8 shows (A) the results of evaluation, by surface
plasmon resonance, of affinity between fusion protein Trx_clone1_2
(SEQ ID NO: 42) including an affinity polypeptide prepared as a
thioredoxin fusion protein (10, 5, and 2.5 nM) and a CH1-CL domain
forming a non-native three-dimensional structure and immobilized on
a sensor chip; (B) the results of evaluation, by surface plasmon
resonance, of affinity between fusion protein Trx_clone2_2 (SEQ ID
NO: 43) including an affinity polypeptide prepared as a thioredoxin
fusion protein (10, 5, and 2.5 nM) and a CH1-CL domain forming a
non-native three-dimensional structure and immobilized on a sensor
chip; (C) the results of evaluation, by surface plasmon resonance,
of affinity between fusion protein Trx_clone3_2 (SEQ ID NO: 44)
including an affinity polypeptide prepared as a thioredoxin fusion
protein (10, 5, and 2.5 nM) and a CH1-CL domain forming a
non-native three-dimensional structure and immobilized on a sensor
chip; (D) the results of evaluation, by surface plasmon resonance,
of affinity between fusion protein Trx_clone13_2 (SEQ ID NO: 45)
including an affinity polypeptide prepared as a thioredoxin fusion
protein (10, 5, and 2.5 nM) and a CH1-CL domain forming a
non-native three-dimensional structure and immobilized on a sensor
chip; and (E) the results of evaluation, by surface plasmon
resonance, of affinity between fusion protein Trx_clone20_2 (SEQ ID
NO: 46) including an affinity polypeptide prepared as a thioredoxin
fusion protein (10, 5, and 2.5 nM) and a CH1-CL domain forming a
non-native three-dimensional structure and immobilized on a sensor
chip.
DESCRIPTION OF EMBODIMENTS
[0126] The present invention relates to a polypeptide having
specific affinity for a protein partially including a CH1-CL domain
forming a non-native three-dimensional structure among proteins
including a CH1-CL domains of an antibody such as IgG or a Fab
region thereof and a method for detecting, immobilizing, or
removing the protein partially including a CH1-CL domain forming a
non-native three-dimensional structure using such an affinity
polypeptide.
[0127] In the present specification, the term "CH1-CL domain" means
a protein associate including a CH1 domain contained in the heavy
chain constant region of IgG and a CL domain contained in the light
chain constant region of IgG. Here, the CH1 domain means a
polypeptide portion of about 100-residue length from the N-terminus
of the IgG heavy chain constant region and capable of forming a
three-dimensional structure consisting of a unique domain as an
immunoglobulin fold. The CL domain means a polypeptide portion of
the IgG light chain constant region and capable of forming a
three-dimensional structure consisting of a unique domain as an
immunoglobulin fold. The CH1-CL domain may exist alone or may be a
part of a protein, such as IgG or a Fab region, as long as the
polypeptide of the present invention shows affinity thereto. The
amino acid sequence of a constant region is known to show homology
within species or also between species. For example, human IgG is
classified into four subclasses of IgG1, IgG2, IgG3, and IgG4 based
on the difference in the amino acid sequence of the heavy chain. In
the amino acid sequences thereof, human IgG1 CH1 domain (UniProt
database, Accession No. P01857), human IgG2 CH1 domain (UniProt
database, Accession No. P01859), human IgG3 CH1 domain (UniProt
database, Accession No. P01860), and human IgG4 CH1 domain (UniProt
database, Accession No. P01861) have a sequence homology of about
90%. The amino acid sequence of the CH1 domain of human IgG1 has a
sequence homology of about 65% with mouse IgG1 CH1 domain (UniProt
database, Accession No. P01868) or rat IgG1 CH1 domain (UniProt
database, Accession No. P20759). Example 1 described below shows
the results when a CH1-CL domain derived from human IgG1 was used,
but the CH1-CL domain is not limited to this, as long as the
polypeptide of the present invention shows affinity to the domain.
In addition, the amino acid residue of the above-mentioned CH1-CL
domain may be modified (substitution, deletion, addition, and/or
insertion) as long as the polypeptide of the present invention
shows affinity thereto. That is, the term "CH1-CL domain" can
include both the natural CH1-CL domain and a modified CH1-CL domain
as long as the polypeptide of the present invention shows affinity
thereto.
[0128] Formation of the non-native three-dimensional structure of a
CH1-CL domain is accompanied by, for example, a change in the
three-dimensional structure, and/or modification of the side chain,
and/or formation of a multimer, and/or cleavage of the disulfide
bond, as shown in the reference documents described below. Even
when a change in the three-dimensional structure of a CH1-CL domain
causes dissociation of the associate, as long as the polypeptide of
the present invention shows affinity thereto, the dissociation
product is also encompassed in the non-native three-dimensional
structure.
[0129] In the present specification, the "non-native
three-dimensional structure" is a collective term for a group of
three-dimensional structures that are different from the native
three-dimensional structures and arise by physical treatment, such
as heating, acid treatment, stirring, shearing, protein-denaturant
treatment, ionic strength change, or light irradiation; or chemical
treatment with, for example, a reducing agent, an oxidant, an acid,
a base, an enzyme, or a catalyst.
[0130] Here, acid treatment means, but not limited to, exposure to
the condition of preferably pH 4.0 or less and more preferably pH
3.0 or less. For example, it is reported that IgG and the domain
constituting IgG form a non-native three-dimensional structure,
called alternatively folded state (AFS), different from the usual
native three-dimensional structure by treatment with an acid buffer
solution of pH 2.0 (Non Patent Literatures 14, 15, and 18).
[0131] In addition, it is known that the three-dimensional
structure of a protein is generally modified by physical or
chemical stress by physical or chemical treatment other than acid
treatment. It is known that a three-dimensional structure is
readily modified most typically by heating or a modifier such as
guanidine hydrochloride (Non Patent Literature 19). For example, in
the Fc region of IgG, formation of an AFS by heat modification at
around 75.degree. C. has been reported (Non Patent Literature 20).
As another chemical or physical treatment, reducing agent treatment
and physical shock such as shearing and stirring are widely known.
The reducing agent treatment here indicates a state in which a part
or whole of intramolecular or intermolecular disulfide bonds are
cleaved. More specifically, the treatment indicates a state in
which disulfide bonds are cleaved by addition of a reducing agent
(e.g., dithiothreitol, .beta.-mercaptoethanol, or
2-mercatoethylamine). As the physical shock such as stirring and
shearing, it has been reported, but not limited to, that oxidation
of amino acid residues, modification of the three-dimensional
structure of a protein, and protein aggregation resulting therefrom
are caused by rotating, for example, an IgG solution with a stirrer
at a speed of 700 rpm (Non Patent Literatures 21 and 22). In the
paragraphs 3) to 5) of Example 1 described below, the results of
evaluation of affinity for IgG and a Fab region treated with an
acid buffer solution are shown, but non-native three-dimensional
structures occurring by treatments other than the acid treatment to
which the polypeptide of the present invention shows affinity are
included among the non-native three-dimensional structures of the
CH1-CL domain.
[0132] One of suitable forms of the amino acid sequence of the
polypeptide of the present invention is a polypeptide represented
by SEQ ID NO: 1 including P-Q-x-I-x-L-x-[IL]-[NT]-[YW] (wherein x
represents an amino acid residue; and brackets represent any one of
the amino acid residues within the brackets) as a common sequence,
and more preferably a polypeptide including an amino acid sequence
represented by SEQ ID NO: 2 or 3. As described in the paragraph 5)
of Example 1 and the paragraph 1) of Example 2 described below, the
present invention encompasses polypeptides including amino acid
sequences derived from the common sequence (SEQ ID NO: 1) by
addition of several amino acid residues, for example, 1 to 20,
preferably 1 to 10, more preferably 1 to 5 amino acid residues
within a range that does not impair the affinity for a CH1-CL
domain forming a non-native three-dimensional structure.
[0133] In addition, as shown in the paragraph 5) of Example 1 and
the paragraph 1) of Example 2 described below, the present
invention includes polypeptides including amino acid sequences
derived from the common sequence (SEQ ID NO: 1) by deletion,
substitution, or insertion of several amino acid residues, for
example, 1 to 6, preferably 1 to 3, more preferably 1 or 2 amino
acid residues within a range that does not impair the affinity for
a CH1-CL domain forming a non-native three-dimensional structure.
Examples of the amino acid sequence represented by Formula 1
include an amino acid sequence represented by SEQ ID NO: 2 or 3,
and the present invention also includes polypeptides including
amino acid sequences derived from the above-mentioned amino acid
sequences by deletion, substitution, or insertion of 1 to 3, 1 or
2, amino acids as long as they have affinity for a CH1-CL domain
forming a non-native three-dimensional structure.
[0134] In Formula 1, since the site represented by x is not
important for the function of the polypeptide, it can be expected
that a polypeptide having an amino acid sequence:
P-Q-[DNEQHFYW]-I-[RKHSTY]-L-[GAVLIPSTY]-[IL]-[NT]-[YW] (wherein
brackets represent any one of the amino acid residues within the
brackets), which is obtained from the amino acid sequence
represented by SEQ ID NO: 2 or 3 by conservative amino acid
substitution of the sites, in particular, a polypeptide having an
amino acid sequence: P-Q-[EW]-I-[RT]-L-[IT]-[IL]-[NT]-[YW] (wherein
brackets represent any one of the amino acid residues within the
brackets), also has the same function.
[0135] The number of the amino acid residues of the polypeptide
sequence is not limited as long as the above-mentioned amino acid
sequence is included. In addition, as shown by examples of affinity
selection using a phage displaying an affinity polypeptide
described in the paragraph 2) of Example 1 and the paragraph 1) of
Example 2 described below, a recombinant phage displaying the
polypeptide on the surface layer by transformation using a nucleic
acid encoding the polypeptide also has affinity for the non-native
three-dimensional structure of a CH1-CL domain. That is, the
present invention encompasses polypeptides having the
above-mentioned amino acid sequences, fusion proteins comprising
the polypeptides, and transformants carrying nucleic acids encoding
the polypeptides or the fusion proteins.
[0136] Further another preferred embodiment relates to a
polypeptide represented by SEQ ID NO: 4 comprising, as a common
sequence, Y-D-P-E-T-G-T-W-P-Q-x-I-x-L-x-[IL]-[NT]-[YW] (wherein x
represents an amino acid residue, and brackets represent any one of
the amino acid residues within the brackets). More preferably, the
polypeptide includes an amino acid sequence represented by SEQ ID
NO: 5 or 6. As in the polypeptides represented by SEQ ID NOs: 36 to
41 shown in the paragraph 1) of Example 2 described below, the
present invention encompasses polypeptides comprising amino acid
sequences having addition of several amino acid residues, for
example, 1 to 20, preferably 1 to 10, more preferably 1 to 5 amino
acid residues in the common sequence (SEQ ID NO: 4), within a range
that does not impair the affinity for a CH1-CL domain forming a
non-native three-dimensional structure. Examples of the amino acid
sequence represented by Formula 2 include an amino acid sequence
represented by SEQ ID NO: 5 or 6, and as in the polypeptides
represented by SEQ ID NOs: 36 to 41 shown in the paragraph 5) of
Example 1 and the paragraph 1) of Example 2 described below, the
present invention also includes polypeptides comprising amino acid
sequences having deletion, substitution, or insertion of several
amino acid residues, for example, 1 to 6, preferably 1 to 3, and
more preferably 1 or 2 amino acid residues in the common sequence
(SEQ ID NO: 4), within a range that does not impair the affinity
for a CH1-CL domain forming a non-native three-dimensional
structure. The number of the amino acid residues of the polypeptide
sequence is not limited as long as an amino acid sequence mentioned
above is included.
[0137] In Formula 2, since the site represented by x is not
important for the function of the polypeptide, it can be expected
that a polypeptide having an amino acid sequence:
Y-D-P-E-T-G-T-W-P-Q-[DNEQHFYW]-I-[RKHSTY]-L-[GAVLIPSTY]-[IL]-[NT]-[YW]
(wherein brackets represent any one of the amino acid residues
within the brackets), which is obtained from the amino acid
sequence represented by any one of SEQ ID NOs: 5, 6, and 36 to 41
by conservative amino acid substitution of the site, in particular,
a polypeptide having an amino acid sequence:
Y-D-P-E-T-G-T-W-P-Q-[EW]-I-[RT]-L-[IT]-[IL]-[NT]-[YW] (wherein
brackets represent any one of the amino acid residues within the
brackets), also has the same function.
[0138] In addition, as shown in affinity selection using a phage
displaying a polypeptide in the paragraph 2) of Example 1 and the
paragraph 1) of Example 2 described below, a recombinant phage
displaying the polypeptide on the surface layer by transformation
using a nucleic acid encoding the polypeptide also has affinity for
the CH1-CL domain forming a non-native three-dimensional structure.
That is, the present invention encompasses polypeptides having the
above-mentioned amino acid sequences, fusion proteins comprising
the polypeptides, and transformants carrying nucleic acids encoding
the polypeptides or the fusion proteins.
[0139] Further another preferred embodiment relates to a
polypeptide comprising, as a common sequence:
P-N-S-G-G-G-G-S-Y-D-P-E-T-G-T-W-P-Q-x-I-x-L-x-[IL]-[NT]-[YW]
(wherein x represents an amino acid residue, and brackets represent
any one of the amino acid residues within the brackets) which is
represented by SEQ ID NO: 7. More preferably, the polypeptide
comprises an amino acid sequence represented by SEQ ID NO: 8 or 9.
As in the polypeptides represented by SEQ ID NOs: 10 to 12 shown in
the paragraph 5) of Example 1 described below, the present
invention encompasses polypeptides consisting of amino acid
sequences having addition of several amino acid residues, for
example, 1 to 20, preferably 1 to 10, more preferably 1 to 5 amino
acid residues in the common sequence (SEQ ID NO: 7), within a range
that does not impair the affinity for the CH1-CL domain forming a
non-native three-dimensional structure. In addition, as in the
polypeptides represented by SEQ ID NOs: 10 to 12 shown in the
paragraph 5) of Example 1 described below, the present invention
encompasses polypeptides comprising amino acid sequences having
deletion, substitution, or insertion of several amino acid
residues, for example, 1 to 6, preferably 1 to 3, more preferably 1
or 2 amino acid residues in the common sequence (SEQ ID NO: 7),
within a range that does not impair the affinity for the CH1-CL
domain forming a non-native three-dimensional structure. The number
of the amino acid residues of the polypeptide sequence is not
limited as long as the above-mentioned amino acid sequence is
included.
[0140] In Formula 3, since the site represented by x is not
important for the function of the polypeptide, it can be expected
that a polypeptide having an amino acid sequence obtained from the
amino acid sequence represented by any one of SEQ ID NOs: 8 to 12
by conservative amino acid substitution of the site, for example,
P-N-S-G-G-G-G-S-Y-D-P-E-T-G-T-W-P-Q-[DNEQHFYW]-1-[RKHSTY]-L-[GAVLIPSTY]-[-
IL]-[NT]-[YW] (wherein brackets represent any one of the amino acid
residues within the brackets), in particular, a polypeptide having
an amino acid sequence:
P--N-S-G-G-G-G-S-Y-D-P-E-T-G-T-W-P-Q-[EW]-1-[RT]-L-[IT]-[IL]-[NT]-[YW]
(wherein brackets represent any one of the amino acid residues
within the brackets), also has the same function.
[0141] In addition, as shown in affinity selection using a phage
displaying a polypeptide in the paragraph 2) of Example 1 and the
paragraph 1) of Example 2 described below, a recombinant phage
displaying the polypeptide on the surface layer by transformation
using a nucleic acid encoding the polypeptide also has affinity for
the CH1-CL domain forming a non-native three-dimensional structure.
That is, the present invention encompasses polypeptides having the
above-mentioned amino acid sequences, fusion proteins comprising
the polypeptides, and transformants carrying nucleic acids encoding
the polypeptides or the fusion proteins.
[0142] The polypeptide of the present invention may be a tandem
polypeptide having a second polypeptide at the amino-terminus, the
carboxyl-terminus, or both termini as long as the polypeptide has
affinity for a CH1-CL domain of immunoglobulin G. Examples of the
second polypeptide include a polypeptide of the present invention
to be linked for improving the affinity by a multivalent effect; a
polypeptide having affinity for another molecule to be linked for
imparting multispecificity; a tag polypeptide, such as a FLAG tag,
a c-myc tag, or a histidine tag, to be linked for purification or
detection of the polypeptide; a polypeptide forming a secondary
structure, such as a leucine zipper or a .beta. hairpin, to be
linked for stabilizing the structure of the polypeptide; a signal
peptide, such as an endoplasmic reticulum signal peptide, to be
linked for promoting organellar localization or extracellular
secretion; and an adhesive polypeptide including, for example, an
RGD motif to be linked for adhesion to the cell surface. Functional
improvement or multi-functionalization by linking a certain
functional polypeptide with a polypeptide having the same or
different function is already known in the art (Non Patent
Literatures 10 and 33 to 35).
[0143] Alternatively, as described above, the polypeptide of the
present invention may be a fusion protein having a protein bound to
the amino-terminus, the carboxyl-terminus, or both termini of a
polypeptide as long as the fusion protein has affinity for a CH1-CL
domain of immunoglobulin G. Examples of the protein to be fused
include a protein to be used for enhancing the solubility of the
polypeptide, such as thioredoxin, maltose binding protein, or
glutathione-S-transferase; a protein to be used for detecting color
development, luminescence, or fluorescence, such as peroxidase,
alkali phosphatase, or fluorescent protein; and a protein having
affinity, such as antibody, Staphylococcus aureus protein A, or
Streptococcus protein G. Improvement in solubility or
multi-functionalization by binding a protein to a polypeptide
having a certain function is already known in the art (Non Patent
Literatures 36 to 38). Examples of the fusion protein of the
present invention include proteins consisting of amino acid
sequences represented by SEQ ID NOs: 13 to 15 and 42 to 46, which
are encoded by nucleic acids represented by SEQ ID NOs: 16 to 18
and 47 to 51, respectively.
[0144] Furthermore, the polypeptide and the fusion protein of the
present invention may be labeled. That is, the present invention
encompasses a modified polypeptide, a modified protein, and a
modified transformant, which are obtained by binding an organic
compound, an inorganic compound, or both compounds to the
above-mentioned polypeptide, fusion protein, or transformant
comprising a nucleic acid encoding the polypeptide or the fusion
protein, within a range that does not impair the affinity for a
CH1-CL domain forming a non-native three-dimensional structure. The
binding of the above-mentioned organic compound, etc. allows
effective detection of a protein partially including a CH1-CL
domain forming a non-native three-dimensional structure, the
detection being an example of the use of the present invention
shown below. Preferred examples of the organic compound, etc.
include fluorescent organic compounds, such as biotin and
fluorescein; fluorescent inorganic compounds, such as a stable
isotope, a phosphate group, an acyl group, an amide group, an ester
group, an epoxy group, polyethylene glycol (PEG), lipid, a
carbohydrate chain, a nucleic acid, and a quantum dot; and
colloidal gold (Non Patent Literature 23), but it is not intended
to exclude any other technically applicable compounds.
[0145] There is no limitation in the use of the polypeptide of the
present invention as long as the affinity for a protein partially
including a CH1-CL domain forming a non-native three-dimensional
structure is utilized. In general, IgG affinity molecules are used
for detection (Patent Literature 5), immobilization (Non Patent
Literature 24), separation/purification (Non Patent Literature 25),
and removal (Patent Literature 6) of a protein including IgG or a
domain derived from IgG. Accordingly, the use of the polypeptide of
the present invention encompasses all technically applicable forms
in the uses known to those skilled in the art including the uses
utilizing IgG affinity molecules described above. As shown in
Example 1 described below, the polypeptide of the present invention
has specific affinity for a CH1-CL domain forming a non-native
three-dimensional structure and therefore can be used for
detection, immobilization, separation/purification, and removal of
a protein partially including the CH1-CL domain. Examples described
below show detection of non-native three-dimensional structures of
IgG, a Fab region, and a CH1-CL domain, but it is not intended to
exclude other usage forms.
[0146] In the present invention, the polypeptide may be synthesized
by any method and may be used in any form. As the method for
preparing an identified polypeptide, a large number of synthetic
methods, such as an organic chemical synthetic method (Non Patent
Literature 26) and a method of expressing the polypeptide as a
fusion protein linked with an arbitrary protein by gene
recombination (Non Patent Literature 27), have been reported, and a
polypeptide of which the amino acid sequence has been identified
can be easily prepared by application of an existing synthesis
technique. Examples described below show preparation by organic
chemical synthesis, preparation by cell expression as a fusion
protein, and a recombinant phage displaying the polypeptide on the
surface layer by transformation using a nucleic acid encoding the
polypeptide as examples, but it is not intended to exclude other
methods and the above-mentioned other techniques.
[0147] The present invention also relates to a solid-phase carrier
immobilizing the polypeptide of the present invention. Here,
preferred examples of the solid-phase carrier include, but not
limited to, resins, such as polystyrene and polyester; biopolymer
compounds, such as dextran and agarose; and inorganic materials,
such as metal and glass. The solid-phase carrier may have any
shape, such as a particle, a plate, a membrane, a chip, and a test
tube. The polypeptide can be immobilized on such a solid-phase
carrier by covalent bonding, physical adsorption, ionic bonding, or
intermolecular interaction. In Example 1 described below, the
peptide is immobilized on the sensor chip of a surface plasmon
resonance measuring apparatus by covalent bonding, but as described
above, it is not intended to exclude other supporting carriers and
immobilization methods. The polypeptide of the present invention
and molecules including the polypeptide, such as a fusion protein,
can be suitably used for detection, immobilization, or removal of a
protein partially including a CH1-CL domain forming a non-native
three-dimensional structure by being immobilized on a solid-phase
carrier. In Examples described below, examples of immobilizing the
polypeptide of SEQ ID NO: 8 on the sensor chip of a surface plasmon
resonance measuring apparatus and thereby detecting IgG and a Fab
region partially including a CH1-CL forming a non-native
three-dimensional structure are described, but the shape of the
solid-phase carrier and the immobilization method are not limited
thereto, and, for example, particles such as magnetic particles and
filter membranes can be suitably applied to the methods for
detecting, immobilizing, or removing proteins known to those
skilled in the art. In addition, the molecules to be detected,
immobilized, or removed are not limited to IgG or a Fab region and
can be a protein partially including a CH1-CL domain forming a
non-native three-dimensional structure, such as a fusion protein of
the CH1-CL domain linked with an arbitrary protein such as a
cytokine or an enzyme.
[0148] Examples of the method for measuring the affinity of a
polypeptide include enzyme-linked immunosorbent assay (ELISA),
surface plasmon resonance (SPR), isothermal titration calorimeter
(ITC), quartz crystal microbalance (QCM), atomic force microscope
(AFM) (Non Patent Literature 28), pull-down assay (Non Patent
Literature 29), electrophoresis (Non Patent Literature 30), and
fluorescence polarization assay (Non Patent Literature 31).
Examples described below show examples of surface plasmon
resonance, but it is not intended to exclude other methods and the
above-mentioned other techniques.
[0149] In the present specification, "having affinity" means that a
binding signal showing a value 10 or more times the binding
signal/noise ratio is obtained by using any one of the
above-mentioned measuring apparatuses.
[0150] It is possible to detect and/or remove a protein partially
including a CH1-CL domain forming a non-native three-dimensional
structure in a sample by using the polypeptide or the fusion
protein of the present invention.
[0151] A method for detecting a protein partially including a
CH1-CL domain forming a non-native three-dimensional structure in a
test sample can comprise the following steps of:
[0152] (1) contacting a test sample with the polypeptide, the
protein, the transformant, the recombinant phage or the recombinant
virus, or the immobilized polypeptide or the immobilized protein of
the present invention, and
[0153] (2) determining whether or not a bond is formed between the
test sample and the polypeptide, the protein, the transformant, the
recombinant phage or the recombinant virus, or the immobilized
polypeptide or the immobilized protein.
[0154] Examples of the method to be used in the step of determining
whether or not a bond is formed include ELISA, SPR, ITC, QCM, AFM,
pull-down assay, electrophoresis, fluorescence polarization assay,
fluorescence resonance energy transfer (FRET), column
chromatography, and immunochromatography. Examples described below
show examples of SPR, but it is not intended to exclude other
technically applicable methods and the above-mentioned other
techniques.
[0155] The method for removing a protein partially including a
CH1-CL domain forming a non-native three-dimensional structure in a
test sample can comprise the following steps of:
[0156] (1) contacting a test sample with the polypeptide, the
protein, the transformant, the recombinant phage or the recombinant
virus, or the immobilized polypeptide or the immobilized protein of
the present invention to bind a protein partially including a
CH1-CL domain forming a non-native three-dimensional structure to
the polypeptide, the protein, the transformant, the recombinant
phage or the recombinant virus, or the immobilized polypeptide or
the immobilized protein, and
[0157] (2) removing the protein partially including a CH1-CL domain
forming a non-native three-dimensional structure bound to the
polypeptide, the protein, the transformant, the recombinant phage
or the recombinant virus, or the immobilized polypeptide or the
immobilized protein from the sample.
[0158] Examples of the method to be used in the step of collection
from the above-mentioned sample include affinity chromatography,
affinity bead assay, affinity filter assay, and
immunoprecipitation, but it is not intended to exclude other
technically applicable methods and the above-mentioned other
techniques.
[0159] The present invention will now be described in detail by
Examples, but is not limited to these Examples.
Example 1
[0160] In this Example, first, it will be described how the amino
acid sequence of a polypeptide having affinity for a CH1-CL domain
forming a non-native three-dimensional structure was identified.
Next, it will be shown examples of measuring the affinity of amino
acid sequences of SEQ ID NOs: 8 and 9 comprising the amino acid
sequence of SEQ ID NO: 7 as a common sequence; an amino acid
sequence of SEQ ID NO: 2 comprising the amino acid sequence of SEQ
ID NO: 1 as a common sequence; synthetic polypeptides derived from
these amino acid sequences each by addition, deletion,
substitution, or insertion of several amino acid residues within a
range that does not impair the affinity for the CH1-CL domain
forming a non-native three-dimensional structure (or a protein
partially including the CH1-CL domain forming a non-native
three-dimensional structure), or fusion polypeptides (SEQ ID NOs:
13 to 15) comprising these amino acid sequences.
[0161] 1) Preparation of CH1-CL domain of human IgG The amino acid
sequence of an affinity polypeptide was identified by affinity
selection based on phage display using T7 phage. In this paragraph,
an example of preparing a human IgG1-derived CH1-CL domain used for
affinity selection will be described.
[0162] An expression vector pET-CH1 in which a DNA fragment
encoding the amino acid sequence (SEQ ID NO: 19) of the CH1 domain
having a histidine (His)6 tag at the N-terminus was introduced into
pET-22b (Novagen) digested with a restriction enzyme Ndel/EcoRI was
produced. Similarly, an expression vector pET-CL in which a DNA
fragment encoding the amino acid sequence (SEQ ID NO: 20) of the CL
domain having a histidine (His)6 tag at the N-terminus was
introduced into a pET-22b vector digested with a restriction enzyme
Ndel/EcoRI was produced.
[0163] Escherichia coli BL21(DE3) strain (Novagen) was transformed
with each of the produced expression vectors by a heat shock
method, and was cultured on an LB agar medium containing ampicillin
at a final concentration of 100 .mu.g/mL at 37.degree. C.
overnight. The transformants were each subcultured in 200 mL of
2.times.YT medium containing ampicillin at a final concentration of
100 .mu.g/mL, and protein expression was induced at a cell density
of O.D.600=0.8 with a final concentration of 1 mM
isopropyl-.beta.-D-galactopyranoside, further followed by shaking
culture for 12 hours. The cells were collected by centrifugation at
7000 rpm for 20 minutes, and the resulting cell pellet was
suspended in a TBS buffer solution (50 mM Tris-HCl, 150 mM NaCl, pH
7.4). The cells were ultrasonicated with Astrason 3000 (Misonix),
and intracellular insoluble fraction was collected by
centrifugation at 12000 rpm for 30 minutes. The collected fraction
was solubilized with a protein denaturant (6 M guanidine
hydrochloride, 20 mM sodium phosphate, 500 mM NaCl, pH 7.4). The
target protein was purified with His GraviTrap (GE Healthcare). The
resulting CH1 domain and CL domain were mixed each at a final
concentration of 25 .mu.M, and disulfide bonds were cleaved with a
final concentration of 2.5 mM 2-mercaptoethanol. The resultant
product was dialyzed against a refolding buffer solution (20 mM
Tris-HCl, 150 mM NaCl, 1 mM EDTA, pH 8.0) at 37.degree. C. for 6
hours to refold the denatured protein. After the dialysis, a
heterodimer CH1-CL domain consisting of a CH1 domain and a CL
domain was collected by gel filtration chromatography using
Superdex 75 10/300 (GE Healthcare). The degree of purification of
the CH1-CL domain was verified by sodium dodecyl sulfate (SDS)
polyacrylamide gel electrophoresis under nonreducing conditions
(FIG. 1).
[0164] 2) Selection of polypeptide having affinity for CH1-CL
domain forming non-native three-dimensional structure by phage
display
[0165] In this paragraph, an example of construction of a phage
display library and affinity selection of a CH1-CL domain forming a
non-native three-dimensional structure using the library will be
described.
[0166] The phage display library used was that displaying
artificial protein libraries (SEQ ID NOs: 21 to 24) each consisting
of an amino acid sequence including microprotein chignolin and a
random amino acid sequence, described in Patent Literature 3 and
Non Patent Literature 12, as fusion proteins with coat protein g10
of bacteriophage T7. A specific procedure is shown below. The
random amino acid residues were encoded as nucleotide sequence NNK
(N represents A, G, C, or T; and K represents G or T). DNA
fragments in which restriction enzyme EcoRI/HindIII digestion sites
were added to each of the DNA fragments (SEQ ID NOs: 25 to 28)
encoding the amino acid sequences of the artificial protein library
were synthesized by polymerase chain reaction (PCR) and were
digested with EcoRI and HindIII, followed by introduction into
T7Select (registered trademark) 10-3 vector (Novagen). In vitro
packaging of the phage was carried out using the introduced vector.
Packaging was performed using T7Select (registered trademark)
Packaging Kit (Novagen) in accordance with the attached
instruction. The phage after packaging was infected to Escherichia
coli BLT5403 strain (Novagen) cultured up to a cell density of
O.D.600=1.0 in 200 mL of an LB medium, followed by shaking culture
for 6 hours to amplify the phage. The medium supernatant was
collected by centrifugation at 7000 rpm for 20 minutes, and added
thereto were 1/6 volume of 50% polyethylene glycol 8000 and 1/10
volume of 5 M NaCl relative to the volume of the solution. The
mixture was stirred overnight at 4.degree. C. to precipitate the
phage. The precipitate was collected by centrifugation at 12000 rpm
for 20 minutes and was solubilized in a TBS-T buffer solution (20
mM Tris-HCl, 150 mM NaCl, 0.05% Tween 20 (registered trademark), pH
7.4). Aggregate in the solubilized solution was removed with a
Syringe Driven filter unit (Millex) of 0.45 .mu.m diameter to
obtain a phage display library solution.
[0167] Subsequently, an example of preparation of magnetic beads
immobilized with a CH1-CL domain forming a non-native
three-dimensional structure to be used in affinity selection will
be described. The CH1-CL domain prepared in the paragraph 1) was
dialyzed against an acid buffer solution (50 mM NaH.sub.2PO.sub.4,
100 mM NaCl, pH 1.0) for 12 hours to accelerate formation of a
non-native three-dimensional structure due to acid denaturation and
was then dialyzed against a neutral buffer solution (50 mM
NaH.sub.2PO.sub.4, 100 mM NaCl, pH 7.4) for neutralization.
Subsequently, 100 .mu.L (30 mg beads/mL) of Dynabeads M-270
Carboxylic Acid (Invitrogen) as magnetic beads was washed with 25
mM MES of pH 5.0 and was mixed with 50 .mu.L of 50 mg/mL
carbodiimide hydrochloride and 50 .mu.L of 50 mg/mL
N-hydroxysuccinimide on ice, followed by stirring at room
temperature for 30 minutes. Subsequently, 60 .mu.g of the CH1-CL
domain forming a non-native three-dimensional structure was added
thereto, further followed by stirring for 30 minutes. After washing
with 50 mM Tris-HCl (pH 7.4), the beads were stored at 4.degree.
C.
[0168] Subsequently, an example of selecting a polypeptide having
affinity for the CH1-CL domain forming a non-native
three-dimensional structure using the prepared phage display
library and the magnetic beads immobilized with the CH1-CL domain
will be described. The magnetic beads immobilized with the CH1-CL
domain forming a non-native three-dimensional structure were washed
with a TBS-T buffer solution twice, and the surfaces of the
magnetic beads were then blocked by contact with a blocking agent
SuperBlock (registered trademark) T20 (TBS) Blocking Buffer (Thermo
Fisher Scientific Inc.) for 1 hour. Subsequently, the phage display
library solution was added to and mixed with the magnetic beads
immobilized with the CH1-CL domain forming a non-native
three-dimensional structure for 1 hour to bind the phage displaying
the affinity polypeptide to the magnetic beads immobilized with the
CH1-CL domain forming a non-native three-dimensional structure.
Subsequently, a complex of the affinity polypeptide display phage
and the magnetic beads immobilized with the CH1-CL domain forming a
non-native three-dimensional structure was collected by magnetic
separation. One milliliter of SuperBlock (registered trademark) T20
(TBS) Blocking Buffer (Thermo Fisher Scientific Inc.) was added to
the collected complex, followed by mixing for 10 minutes. The
supernatant was removed again by magnetic separation, and the beads
were washed. This washing operation was repeated 10 times, and 1 mL
of a TBS-T buffer solution containing 1% (w/v) sodium dodecyl
sulfate (SDS) was added to the complex collected by magnetic
separation, followed by mixing for 10 minutes to elute the phage
displaying the affinity polypeptide from the CH1-CL
domain-immobilized magnetic beads. The eluted phage was infected to
Escherichia coli BLT5403 strain (Novagen) cultured up to a cell
density of O.D.600=1.0 in 200 mL of an LB medium, followed by
shaking culture for 4 hours. The medium supernatant was collected
by centrifugation at 7000 rpm for 20 minutes, and added thereto
were 1/6 volume of 50% polyethylene glycol 8000 and 1/10 volume of
5 M NaCl relative to the volume of the solution. The mixture was
stirred overnight at 4.degree. C. to precipitate the phage. The
precipitate was collected by centrifugation at 12000 rpm for 20
minutes and was solubilized in a TBS-T buffer solution (20 mM
Tris-HCl, 150 mM NaCl, 0.05% Tween 20 (registered trademark), pH
7.4). Aggregate in the solubilized solution was removed with a
Syringe Driven filter unit (Millex) of 0.45 .mu.m diameter to
prepare a phage solution. The selection step described above was
repeated five times to concentrate the phage displaying a
polypeptide having affinity for the CH1-CL domain forming a
non-native three-dimensional structure.
[0169] 3) Identification of polypeptide having affinity for CH1-CL
domain forming non-native three-dimensional structure
[0170] In this paragraph, an example of determining the amino acid
sequence of a polypeptide having affinity for the CH1-CL domain
forming a non-native three-dimensional structure will be
described.
[0171] Using as a template the solution of phage displaying the
polypeptide having affinity for the CH1-CL domain forming a
non-native three-dimensional structure and concentrated by affinity
selection described in the preceding paragraph, the DNA of the
artificial protein library region introduced into a T7 phage genome
was amplified by PCR. The PCR was performed using a KOD DNA
polymerase (TOYOBO CO., LTD.) under reaction conditions in
accordance with the attached manual. The amplified DNA was digested
with EcoRI and HindIII and introduced into the region digested at
the EcoRI/HindIII site of pET-48b (Invitrogen) to construct an
expression vector expressing the polypeptide, which is a
translation product of the artificial protein library gene, as a
fusion protein linked to the C-terminus of thioredoxin. Escherichia
coli BL21 (DE3) strain was transformed by a heat shock method using
the constructed expression vector and was cultured on an LB agar
medium containing 50 .mu.g/mL of kanamycin. From the resulting
colonies, 36 clones were randomly isolated and were cultured with
shaking in 700 .mu.L of an LB medium. At the stage of a cell
density of O.D.600=1.0, expression was induced with a final
concentration of 1 mM isopropyl-.beta.-thiogalactopyranoside,
followed by culturing at 37.degree. C. for 12 hours. The cells were
collected by centrifugation at 7000 rpm, suspended in a TBS-T
buffer solution, and then ultrasonicated for 20 minutes with a
hermetically sealed ultrasonicator Bioruptor (COSMO BIO). The
cell-disrupted solution was centrifugated at 12000 rpm, and the
supernatant was collected and then roughly purified by metal
chelate affinity chromatography using His SpinTrap (GE Healthcare)
to prepare a thioredoxin fusion protein including the affinity
polypeptide.
[0172] Subsequently, an example of measuring the affinity between
the isolated/purified thioredoxin fusion protein and the CH1-CL
domain forming a non-native three-dimensional structure by surface
plasmon resonance (SPR) will be described. As the SPR measuring
apparatus, Biacore T100 (GE Healthcare) was used. A CH1-CL domain
was dialyzed against an acid buffer solution (50 mM
NaH.sub.2PO.sub.4, 100 mM NaCl, pH 2.0) for 12 hours to accelerate
formation of a non-native three-dimensional structure due to acid
denaturation and was then dialyzed against an HBS-T buffer solution
(10 mM HEPES, 150 mM NaCl, 0.05% Tween 20 (registered trademark),
pH 7.4) for neutralization. The CH1-CL domain was immobilized on a
sensor chip CM5 (GE Healthcare) by amine coupling. Thirty-two
purified thioredoxin fusion proteins were diluted with an HBS-T
buffer solution to 5 .mu.M and 2 .mu.M. SPR measurement was
performed using an HBS-T buffer solution as the running buffer
solution and 100 mM glycine-HCl of pH 2.0 as the regenerating
solution at a reaction temperature of 25.degree. C. The results of
SPR sensorgrams of the 32 clones in total are shown in FIG. 2.
Table 1 shows whether affinity was present or not between each of
the 32 clones and the CH1-CL domain forming a non-native
three-dimensional structure. Eight clones (Clone 1, Clone 2, Clone
9, Clone 12, Clone 17, Clone 24, Clone 27, and Clone 31) showed
affinity for the CH1-CL domain forming a non-native
three-dimensional structure (Table 1).
TABLE-US-00009 TABLE 1 Clone (SEQ ID NO) Non-native CH1-CL Clone 1
(14) Binding Clone 2 (13) Binding Clone 3 (N/D) No-binding Clone 4
(N/D) No-binding Clone 5 (N/D) No-binding Clone 6 (N/D) No-binding
Close 7 (N/D) No-binding Clone 8 (N/D) No-binding Clone 9 (14)
Binding Clone 10 (N/D) No-binding Clone 11 (N/D) No-binding Clone
12 (14) Binding Clone 13 (N/D) No-binding Clone 14 (N/D) No-binding
Clone 15 (N/D) No-binding Clone 16 (N/D) No-binding Clone 17 (14)
Binding Clone 18 (N/D) No-binding Clone 19 (N/D) No-binding Clone
20 (N/D) No-binding Clone 21 (N/D) No-binding Clone 22 (N/D)
No-binding Clone 23 (N/D) No-binding Clone 24 (14) Binding Clone 25
(N/D) No-binding Clone 26 (N/D) No-binding Clone 27 (14) Binding
Clone 28 (N/D) No-binding Clone 29 (N/D) No-binding Clone 30 (N/D)
No-binding Clone 31 (15) Binding Clone 32 (N/D) No-binding
[0173] Subsequently, the eight clones (Clone 1, Clone 2, Clone 9,
Clone 12, Clone 17, Clone 24, Clone 27, and Clone 31) showed
affinity for the CH1-CL domain forming a non-native
three-dimensional structure in the SPR test were analyzed for the
DNA sequences of the thioredoxin fusion proteins including the
affinity polypeptides by a dideoxy method with Applied Biosystems
(registered trademark) 3500 Genetic Analyzer to determine the amino
acid sequences. The amino acid sequences of six clones in the eight
clones were identical, and three amino acid sequences (SEQ ID NOs:
13 to 15) were finally identified as independent amino acid
sequences. Regarding each of the amino acid sequences of these
thioredoxin fusion proteins, the region excluding the amino acid
sequences of common sequences: thioredoxin (SEQ ID NO: 29), the
linker region (SEQ ID NO: 30), and microprotein chignolin (SEQ ID
NO: 31) was identified as the amino acid sequence (SEQ ID NOs: 2,
3, or 32) of the region selected from random amino acid sequences
by affinity selection. The amino acid sequences of the three clones
have high homology and were recognized to commonly include a
proline residue, a glutamine residue, an isoleucine residue, or a
leucine residue.
[0174] 4) Characteristic analysis of polypeptide having affinity
for CH1-CL domain forming non-native three-dimensional
structure
[0175] In this paragraph, an example of characterizing the
specificity of a polypeptide having affinity for a CH1-CL domain
forming a non-native three-dimensional structure will be
described.
[0176] Polypeptide AF.ab9 (SEQ ID NO: 8) in which 8-residue linker
sequence (Pro-Asn-Ser-Gly-Gly-Gly-Gly-Ser) (SEQ ID NO: 30) and
8-residue chignolin sequence (Tyr-Asp-Pro-Glu-Thr-Gly-Thr-Trp) (SEQ
ID NO: 31) were added to the amino acid sequence (SEQ ID NO: 2)
identified in the preceding paragraph was designed and
organic-chemically synthesized. Preparation of the synthesized
polypeptide was entrusted to GL Biochem (Shanghai). AF.ab9 was
dissolved in a boric acid buffer solution (10 mM Borate-Na, 1 M
NaCl, pH 8.5) and was immobilized on a sensor chip CM5 (GE
Healthcare) by amine coupling.
[0177] Subsequently, human monoclonal IgG, Fab region, and Fc
region having a native three-dimensional structure and a non-native
three-dimensional structure were prepared. The Fab region and Fc
region were prepared by subjecting human monoclonal IgG to papain
digestion with Pierce (registered trademark) Fab Preparation Kit
(Thermo Fisher Scientific Inc.) and then to purification by
affinity chromatography using MabSelect SuRe (GE Healthcare), anion
exchange chromatography using HiTrap DEAE (GE Healthcare), and gel
filtration chromatography using
[0178] Superdex 200 (GE Healthcare). The IgG, Fab region, and Fc
region were each diluted to 5 .mu.M and dialyzed against an acid
buffer solution (50 mM NaH.sub.2PO.sub.4, 100 mM NaCl, pH 2.0) for
12 hours for accelerating acid denaturation and dialyzed against an
HBS-T buffer solution for neutralization.
[0179] Acid-treated or acid-untreated IgG, Fab region, and Fc
region were each diluted to 2, 1, 0.5, 0.25, and 0.125 .mu.M and
were measured for affinity for AF.ab9 with Biacore T100 (GE
Healthcare) (FIG. 3, Table 2). Table 2 shows whether affinity was
present or not between acid-treated IgG, acid-treated antibody
domain, native IgG, or native antibody domain and AF.ab9.
TABLE-US-00010 TABLE 2 IgG or antibody fragment AF.ab9 (SEQ ID NO:
8) Native IgG No-binding pH 2.0-treated IgG Binding Native Fab
No-binding pH 2.0-treated Fab Binding Native Fc No-binding pH
2.0-treated Fc No-binding pH 4.0-treated IgG No-binding pH
3.0-treated IgG Binding
[0180] Regarding the IgG and Fab region including a CH1-CL domain,
AF.ab9 did not show a significant binding response to the
acid-untreated IgG and Fab region having the native
three-dimensional structure (FIGS. 3 (A) and (C)), but showed a
strong binding response to the acid-treated IgG and Fab region,
i.e., IgG and Fab region having the CH1-CL domain forming the
non-native three-dimensional structure (FIGS. 3 (B) and (D)). This
result demonstrates that AF.ab9 distinguishes between the native
three-dimensional structure and the non-native three-dimensional
structure of IgG and Fab regions and has affinity for IgG forming a
non-native three-dimensional structure and a Fab region forming a
non-native three-dimensional structure. In contrast, regarding the
Fc region not including a CH1-CL domain, AF.ab9 did not show a
binding response to the acid-untreated Fc region having the native
three-dimensional structure (FIG. 3 (E)), and the binding response
to the acid-treated Fc region was only 1/100 or less compared with
that on the non-native structure of the Fab region (FIG. 3 (F)). In
a past report, it was observed that the CH3 domain in Fc region
forms a non-native three-dimensional structure by acid treatment at
pH 2 and subsequent neutralization treatment (Non Patent Literature
18). This indicates that the Fc region also forms a non-native
three-dimensional structure by acid treatment as in the Fab region
and further indicates that AF.ab9 specifically distinguishes the
difference between the non-native three-dimensional structures of
the Fab region and the Fc region. This is consistent with that the
amino acid sequence included in AF.ab9 is the polypeptide selected
by affinity for the CH1-CL domain forming a non-native
three-dimensional structure.
[0181] Subsequently, an example of evaluating the affinity of
AF.ab9 for IgG treated with buffer solutions having different
degrees of acidity will be described. IgG was dissolved in an HBS
buffer solution (10 mM HEPES, 150 mM NaCl, pH 7.4) at a
concentration of 5 .mu.M. The acidity of a sodium phosphate buffer
solution (50 mM NaH.sub.2PO.sub.4, 100 mM NaCl) as an acid buffer
solution was adjusted to three degrees of pH 2.0, pH 3.0, and pH
4.0. An antibody was dialyzed against each of the buffer solutions
for 12 hours and was then dialyzed against an HBS-T buffer solution
for neutralization. The affinity of each of the resulting
acid-treated IgG for AF.ab9 was measured by SPR (FIG. 4, Table 2).
The SPR test was conducted in accordance with the conditions
described above in this paragraph. The results of the SPR test
demonstrated that AF.ab9 did not show a significant binding
response to the IgG treated with the buffer solution of pH 4.0
(FIG. 4 (A)), but showed clear binding responses on the
acid-treated IgG at pH 3.0 and pH 2.0 and showed a pH-dependent
increase in the binding signal (FIGS. 4 (B) and (C)). This result
suggests that the non-native three-dimensional structure recognized
by AF.ab9 increases with the degree of acidity and that the change
in the structure of the CH1-CL domain significantly occurs between
pH 4.0 and pH 3.0. Regarding the acid denaturation of the CH1-CL
domain, it has been reported as the results of analysis by
spectroscopic methods such as CD spectrum and fluorescence spectrum
that a clear change in the three-dimensional structure of the
CH1-CL domain occurs between pH 4.0 and pH 3.0 (Non Patent
Literature 32). The pH dependence of the binding response shown in
this Example indicates that a non-native three-dimensional
structure formed by acid denaturation, which has been
spectroscopically proved, is detected by AF.ab9.
[0182] 5) In this paragraph, an example of measuring the affinity
of a polypeptide derived from a polypeptide having affinity for the
CH1-CL domain forming a non-native three-dimensional structure by
addition, deletion, or substitution of one or several amino acid
residues in the amino acid sequence will be described.
[0183] AF.ab9 consists of three regions, i.e., an 8-residue linker
region (SEQ ID NO: 30), a region consisting of 8-residue
microprotein chignolin (SEQ ID NO: 31), and a region selected from
the 10-residue random amino acid sequences by affinity selection in
the paragraph 2). In order to verify the participation, in the
affinity, of the region selected from the random amino acid
sequences among these components, the following three polypeptides,
AF.ab9 (SEQ ID NO: 8), AF.ab9 body (SEQ ID NO: 33), and AF.ab9 arm
(SEQ ID NO: 2), were organic-chemically synthesized. Here, the
AF.ab9 body is a 16-residue polypeptide consisting of the 8-residue
linker region and the 8-residue microprotein chignolin, and the
AF.ab9 arm is a 10-residue polypeptide consisting of a region
selected from the random amino acid sequences. The preparation of
the polypeptides was entrusted to GL Biochem (Shanghai). A peptide
was diluted to 4, 2, and 1 .mu.M with an HBS-T buffer solution, and
the affinity thereof for the CH1-CL domain forming a non-native
three-dimensional structure prepared by the same method as in the
paragraph 3) was measured with Biacore T100 (GE Healthcare) (FIG.
5, Table 3). The measurement conditions were in accordance with
those in the paragraph 3). Table 3 shows whether affinity was
present or not between each synthetic peptide and the CH1-CL domain
forming a non-native three-dimensional structure.
TABLE-US-00011 TABLE 3 Peptide (SEQ ID NO) Non-native CH1-CL domain
AF.ab9 (8) Binding AF.ab9 arm (2) Binding AF.ab9 body (33)
No-binding AF.ab31 (9) Binding AF.ab9 P17A (10) Binding AF.ab9 Q18A
(11) Binding AF.ab9 L24A (12) Binding
[0184] AF.ab9 and AF.ab9 arm showed affinity for the CH1-CL domain
forming a non-native three-dimensional structure (FIGS. 5 (A) and
(B)). In contrast, AF.ab9 body consisting of the linker region and
chignolin did not show significant affinity (FIG. 5 (C)). This
indicates that the region having affinity in AF.ab9 is the region
selected from the 10-residue random amino acid sequences and that
the affinity for the CH1-CL domain forming a non-native
three-dimensional structure is maintained even when a non-affinity
polypeptide, such as a linker region, is added to the affinity
polypeptide.
[0185] Subsequently, an example of measuring the affinity of a
polypeptide derived from an affinity polypeptide by substitution of
one or several amino acid residues in the amino acid sequence and
an example of evaluating the influence of the amino acid residue
showing convergence in affinity selection on the affinity among the
10-residue amino acid sequences selected by affinity selection will
be described.
[0186] AF.ab31 (SEQ ID NO: 9), which is one of the amino acid
sequences identified by affinity selection, was selected as an
example of the polypeptide derived from AF.ab9 by substitution of
several amino acid residues and was organic-chemically synthesized.
The preparation of the polypeptide was entrusted to GL Biochem
(Shanghai).
[0187] Incidentally, as a method for identifying an amino acid
residue important for a function, mutant analysis (alanine
scanning) by substituting a target residue with an alanine residue
is generally employed. Here, alanine scanning was performed for the
amino acid residue at the site particularly showed convergence of
the sequence in affinity selection, and the influence of the amino
acid residue on the affinity was evaluated. Variants, AF.ab9 P17A
(SEQ ID NO: 10), AF.ab9 Q18A (SEQ ID NO: 11), and AF.ab9 L24A (SEQ
ID NO: 12) in which the proline residue at position 17 (Pro17), the
glutamine residue at position 18 (Q1n18), and the leucine residue
at position 24 (Leu24) showing convergence in affinity selection
were substituted with alanine residues were organic-chemically
synthesized. The preparation of the polypeptide was entrusted to GL
Biochem (Shanghai).
[0188] The CH1-CL domain forming a non-native three-dimensional
structure prepared by the same method as in the paragraph 3) was
immobilized on a sensor chip CM5 (GE Healthcare) by amine coupling,
and the binding thereof to AF.ab31, AF.ab9, and alanine
substitution products was measured with Biacore T100 (FIGS. 6 and
7, Table 3).
[0189] The affinity of AF.ab31 (FIG. 6 (B)) was substantially
equivalent to the measurement result of AF.ab9 (FIG. 6 (A)). Based
on this result, a common sequence involved in the affinity was
examined from the amino acid sequences of AF.ab31 and AF.ab9. The
results of the above-described affinity test (FIG. 5) indicate that
the site involved in the affinity is a region derived from a
10-residue random amino acid sequence. Comparison of the amino acid
sequences of AF.ab31 and AF.ab9 in this region demonstrated that
the amino acid residues of four sites of positions 17, 18, 20, and
22 were perfectly identical; the amino acid residues of three sites
of positions 24, 25, and 26 were identical as amino acid residues
showing similar physical properties, such as a hydrophobic amino
acid residue (leucine or isoleucine), a polar amino acid residue
(asparagine or threonine), and a polar aromatic ring amino acid
residue (tryptophan or tyrosine); and three sites of positions 19,
21, and 23 were substituted as the amino acid residues different in
properties. Based on this result, Formulas 1, 2, and 3 (SEQ ID NOs:
1, 4, and 7) were deduced as common sequences having affinity.
[0190] In variants, AF.ab9 P17A and AF.ab9 L24A in which the
proline residue at position 17 and the leucine residue at position
24, respectively, were substituted with alanine residues, the
binding response decreased compared to the measurement results of
AF.ab9 (FIG. 7 (A)), which suggested that these residues are
important for affinity for the CH1-CL domain forming a non-native
three-dimensional structure (FIGS. 7 (B) and (D)). In contrast,
substitution of the glutamine residue at position 18 with an
alanine residue did not largely decrease the affinity for the
CH1-CL domain forming a non-native three-dimensional structure
(FIG. 7 (C)).
Example 2
[0191] In this Example, amino acid sequences of SEQ ID NOs: 36 to
41 comprising the amino acid sequence of SEQ ID NO: 5 as a common
sequence were identified as polypeptides having affinity for a
CH1-CL domain forming a non-native three-dimensional structure, and
an example measuring the affinity of fusion proteins comprising
these amino acid sequences for the CH1-CL domain will be
described.
[0192] 1) In this paragraph, an example of constructing a phage
display library and identifying the amino acid sequence of an
affinity polypeptide using the library by affinity selection for a
CH1-CL domain forming a non-native three-dimensional structure will
be described. The phage display library used was that displaying an
artificial protein library (SEQ ID NO: 34) consisting of an amino
acid sequence including a 10-amino acid residue random amino acid
sequence on the N-terminus side of the amino acid sequence (SEQ ID
NO: 5) identified in Example 1 as a fusion protein with coat
protein g10 of bacteriophage T7. A specific procedure is shown
below. The random amino acid residue was encoded by a nucleotide
sequence NNK (N represents A, G, C, or T; and K represents G or T).
A DNA fragment in which a DNA encoding a restriction enzyme EcoRI
digestion site and a (Gly).sub.4-Ser linker was added to the 5' end
of the DNA fragment (SEQ ID NO: 35) encoding the amino acid
sequence of the artificial protein library and a stop codon and a
HindIII digestion site were added to the 3' end of the DNA fragment
was synthesized by polymerase chain reaction (PCR) and was digested
with EcoRI and HindIII, followed by introduction into T7Select
(registered trademark) 1-1 vector (Merck KGaA). In vitro packaging
of the phage was carried out using the introduced vector. Packaging
was performed using T7Select (registered trademark) Packaging Kit
(Merck KGaA) in accordance with the attached instruction. The phage
after packaging was infected to Escherichia coli BLT5403 strain
(Merck KGaA) cultured up to a cell density of O.D.600=1.0 in 200 mL
of an LB medium, followed by shaking culture for 6 hours to amplify
the phage. The medium supernatant was collected by centrifugation
at 7000 rpm for 20 minutes, and added thereto were 1/6 volume of
50% polyethylene glycol 8000 and 1/10 volume of 5 M NaCl relative
to the volume of the solution. The mixture was stirred overnight at
4.degree. C. to precipitate the phage. The precipitate was
collected by centrifugation at 12000 rpm for 20 minutes and was
solubilized in a TBS-T buffer solution (20 mM Tris-HCl, 150 mM
NaCl, 0.05% Tween 20 (registered trademark), pH 7.4). Aggregate in
the solubilized solution was removed with a Syringe Driven filter
unit (Millex) of 0.45 .mu.m diameter to prepare a phage display
library solution.
[0193] Subsequently, an example of selecting a polypeptide having
affinity for the CH1-CL domain forming a non-native
three-dimensional structure using the prepared phage display
library will be described. The CH1-CL domain was prepared by the
same method as in Example 1. Biotin was chemically bonded to the
prepared CH1-CL domain via an amino group using Biotinamidohexanoic
acid N-hydroxysuccinimide ester (SIGMA-ALDRICH Japan LLC). The
CH1-CL domain was dialyzed against an acid buffer solution (50 mM
NaH.sub.2PO.sub.4, 100 mM NaCl, pH 1.0) for 12 hours to accelerate
formation of a non-native three-dimensional structure due to acid
denaturation and was then dialyzed against a neutral buffer
solution (50 mM NaH.sub.2PO.sub.4, 100 mM NaCl, pH 7.4) for
neutralization. The CH1-CL domain forming a non-native
three-dimensional structure was immobilized on magnetic beads
Streptavidin MagneSphere (registered trademark) Paramagnetic
Particles (Promega Corporation). The immobilized magnetic beads
were washed with a TBS-T buffer solution twice, and the surfaces of
the magnetic beads were then blocked by contact with a blocking
agent SuperBlock (registered trademark) T20 (TBS) Blocking Buffer
(Thermo Fisher Scientific Inc.) for 1 hour. Subsequently, the phage
display library solution was added to the magnetic beads
immobilized with the CH1-CL domain forming a non-native
three-dimensional structure, followed by mixing for 1 hour to bind
the phage displaying the affinity polypeptide to the magnetic beads
immobilized with the CH1-CL domain forming a non-native
three-dimensional structure. Subsequently, a complex of the
affinity polypeptide display phage and the magnetic beads
immobilized with the CH1-CL domain forming a non-native
three-dimensional structure was collected by magnetic separation.
One milliliter of SuperBlock (registered trademark) T20 (TBS)
Blocking Buffer (Thermo Fisher Scientific Inc.) was added to the
collected complex, mixing was performed for 10 minutes, the
supernatant was removed again by magnetic separation, and the beads
were washed. This washing operation was repeated 10 times, and 1 mL
of a TBS-T buffer solution containing 1% (w/v) sodium dodecyl
sulfate (SDS) was added to the complex collected by magnetic
separation, followed by mixing for 10 minutes to elute the phage
displaying the affinity polypeptide from the CH1-CL
domain-immobilized magnetic beads. The eluted phage was infected to
Escherichia coli BLT5403 strain (Merck KGaA) cultured up to a cell
density of O.D.600=1.0 in 200 mL of an LB medium, followed by
shaking culture for 4 hours. The medium supernatant was collected
by centrifugation at 7000 rpm for 20 minutes, and added thereto
were 1/6 volume of 50% polyethylene glycol 8000 and 1/10 volume of
5 M NaCl relative to the volume of the solution. The mixture was
stirred overnight at 4.degree. C. to precipitate the phage. The
precipitate was collected by centrifugation at 12000 rpm for 20
minutes and was solubilized in a TBS-T buffer solution (20 mM
Tris-HCl, 150 mM NaCl, 0.05% Tween 20 (registered trademark), pH
7.4). Aggregate in the solubilized solution was removed with a
Syringe Driven filter unit (Millex) of 0.45 .mu.m diameter to
prepare a phage solution. The selection step described above was
repeated six times to concentrate the phage displaying a
polypeptide having affinity for the CH1-CL domain forming a
non-native three-dimensional structure. Thirty-two clones were
randomly isolated from concentrated phage group, and the amino acid
sequence of the affinity polypeptide region was analyzed using
Applied Biosystems (registered trademark) 3500 Genetic Analyzer.
Duplication was recognized in the amino acid sequences of the
affinity polypeptides of the isolated clones, and six affinity
polypeptides having independent amino acid sequences were
identified (SEQ ID NOs: 36 to 41).
[0194] 2) In this paragraph, an example of preparing a thioredoxin
fusion protein with an affinity polypeptide consisting of the amino
acid sequence identified in the preceding paragraph and measuring
the affinity for the CH1-CL domain forming a non-native
three-dimensional structure using the thioredoxin fusion protein
will be described.
[0195] The DNA region encoding the affinity polypeptide region was
amplified by PCR using each of the phage solutions displaying
affinity polypeptides (SEQ ID NOs: 36 to 40) consisting of the
amino acid sequences identified in the preceding paragraph as
templates. The PCR was performed using a KOD DNA polymerase (TOYOBO
CO., LTD.) under reaction conditions in accordance with the
attached manual. The amplified DNA was digested with EcoRI and
HindIII and introduced into the region digested at the
EcoRI/HindIII site of pET-48b (Merck KGaA) to construct an
expression vector expressing the affinity polypeptide as a fusion
protein linked to the C-terminus of thioredoxin. Escherichia coli
BL21 (DE3) strain (Merck KGaA) was transformed by a heat shock
method using the constructed expression vector and was cultured on
an LB agar medium containing 50 .mu.g/mL of kanamycin. The
transformant was cultured with shaking in 200 mL of 2.times.YT
medium, and at the stage of a cell density of O.D.600=1.0,
expression was induced with a final concentration of 1 mM
isopropyl-.beta.-thiogalactopyranoside, followed by culturing at
37.degree. C. for 12 hours. The cells were collected by
centrifugation at 7000 rpm, suspended in a TBS-T buffer solution,
and then ultrasonicated. The cell-disrupted solution was
centrifugated at 12000 rpm, and the supernatant was collected and
then purified by metal chelate affinity chromatography using His
SpinTrap (GE Healthcare) to prepare a thioredoxin fusion proteins
(SEQ ID NOs: 42 to 46) including the affinity polypeptides.
[0196] Subsequently, an example of measuring the affinity between
the prepared thioredoxin fusion protein and the CH1-CL domain
forming a non-native three-dimensional structure by surface plasmon
resonance (SPR) will be described. As the SPR measuring apparatus,
Biacore T200 (GE Healthcare) was used. The CH1-CL domain was
dialyzed against an acid buffer solution (50 mM NaH.sub.2PO.sub.4,
100 mM NaCl, pH 1.0) for 12 hours to accelerate formation of a
non-native three-dimensional structure due to acid denaturation and
was then dialyzed against an HBS-T buffer solution (10 mM HEPES,
150 mM NaCl, 0.05% Tween 20 (registered trademark), pH 7.4) for
neutralization. The CH1-CL domain was immobilized on a sensor chip
CM5 (GE Healthcare) by amine coupling. SPR measurement was
performed using the prepared thioredoxin fusion protein as the
analyte, an HBS-T buffer solution as the running buffer solution,
and 100 mM glycine-HCl of pH 2.0 as the regenerating solution at a
reaction temperature of 25.degree. C. The results of SPR
sensorgrams of the thioredoxin fusion proteins (SEQ ID NOs: 42 to
46) are shown in FIG. 8 (A) to (E). The measurement data was
treated with Biacore T200 Evaluation Software (GE Healthcare), and
the affinity was calculated as the equilibrium dissociation
constant K.sub.D. The results are shown in Table 4.
TABLE-US-00012 TABLE 4 Clone (SEQ ID NO) K.sub.D (nM) Trx_clone 1_2
(42) 4.5 Trx_clone 2_2 (43) 3.0 Trx_clone 3_2 (44) 2.5 Trx_clone
13_2 (45) 2.8 Trx_clone 20_2 (46) 2.2
INDUSTRIAL APPLICABILITY
[0197] The polypeptide of the present invention has specific
affinity for proteins partially including a CH1-CL domain of
immunoglobulin G, the CH1-CL domain being forming a non-native
three-dimensional structure, and is therefore useful for detection,
immobilization, or removal of these proteins.
[0198] All publications, patents, and patent applications cited in
the present specification are incorporated herein by reference in
their entirety.
Sequence Listing Free Text
[0199] SEQ ID NO: 1: IgG binding peptide
[0200] SEQ ID NO: 2: IgG binding peptide
[0201] SEQ ID NO: 3: IgG binding peptide
[0202] SEQ ID NO: 4: IgG binding peptide
[0203] SEQ ID NO: 5: IgG binding peptide
[0204] SEQ ID NO: 6: IgG binding peptide
[0205] SEQ ID NO: 7: IgG binding peptide
[0206] SEQ ID NO: 8: IgG binding peptide
[0207] SEQ ID NO: 9: IgG binding peptide
[0208] SEQ ID NO: 10: IgG binding peptide
[0209] SEQ ID NO: 11: IgG binding peptide
[0210] SEQ ID NO: 12: IgG binding peptide
[0211] SEQ ID NO: 13: IgG binding peptide
[0212] SEQ ID NO: 14: IgG binding peptide
[0213] SEQ ID NO: 15: IgG binding peptide
[0214] SEQ ID NO: 16: oligo DNA
[0215] SEQ ID NO: 17: oligo DNA
[0216] SEQ ID NO: 18: oligo DNA
[0217] SEQ ID NO: 21: peptide library
[0218] SEQ ID NO: 22: peptide library
[0219] SEQ ID NO: 23: peptide library
[0220] SEQ ID NO: 24: peptide library
[0221] SEQ ID NO: 25: oligo DNA
[0222] SEQ ID NO: 26: oligo DNA
[0223] SEQ ID NO: 27: oligo DNA
[0224] SEQ ID NO: 28: oligo DNA
[0225] SEQ ID NO: 30: synthetic peptide
[0226] SEQ ID NO: 31: synthetic peptide
[0227] SEQ ID NO: 32: IgG binding peptide
[0228] SEQ ID NO: 33: synthetic peptide
[0229] SEQ ID NO: 34: peptide library
[0230] SEQ ID NO: 35: oligo DNA
[0231] SEQ ID NO: 36: IgG binding peptide
[0232] SEQ ID NO: 37: IgG binding peptide
[0233] SEQ ID NO: 38: IgG binding peptide
[0234] SEQ ID NO: 39: IgG binding peptide
[0235] SEQ ID NO: 40: IgG binding peptide
[0236] SEQ ID NO: 41: IgG binding peptide
[0237] SEQ ID NO: 42: IgG binding peptide
[0238] SEQ ID NO: 43: IgG binding peptide
[0239] SEQ ID NO: 44: IgG binding peptide
[0240] SEQ ID NO: 45: IgG binding peptide
[0241] SEQ ID NO: 46: IgG binding peptide
[0242] SEQ ID NO: 47: oligo DNA
[0243] SEQ ID NO: 48: oligo DNA
[0244] SEQ ID NO: 49: oligo DNA
[0245] SEQ ID NO: 50: oligo DNA
[0246] SEQ ID NO: 51: oligo DNA
Sequence CWU 1
1
51110PRTArtificial SequenceSynthetic IgG binding
peptidemisc_feature(3)..(3)Xaa can be any naturally occurring amino
acidmisc_feature(5)..(5)Xaa can be any naturally occurring amino
acidmisc_feature(7)..(7)Xaa can be any naturally occurring amino
acidmisc_feature(8)..(8)Xaa is Ile or Leumisc_feature(9)..(9)Xaa is
Asn or Thrmisc_feature(10)..(10)Xaa is Tyr or Trp 1Pro Gln Xaa Ile
Xaa Leu Xaa Xaa Xaa Xaa1 5 10210PRTArtificial SequenceSynthetic IgG
binding peptide 2Pro Gln Glu Ile Arg Leu Ile Leu Asn Trp1 5
10310PRTArtificial SequenceSynthetic IgG binding peptide 3Pro Gln
Trp Ile Thr Leu Thr Ile Thr Tyr1 5 10418PRTArtificial
SequenceSynthetic IgG binding peptidemisc_feature(11)..(11)Xaa can
be any naturally occurring amino acidmisc_feature(13)..(13)Xaa can
be any naturally occurring amino acidmisc_feature(15)..(15)Xaa can
be any naturally occurring amino acidmisc_feature(16)..(16)Xaa is
Ile or Leumisc_feature(17)..(17)Xaa is Asn or
Thrmisc_feature(18)..(18)Xaa is Tyr or Trp 4Tyr Asp Pro Glu Thr Gly
Thr Trp Pro Gln Xaa Ile Xaa Leu Xaa Xaa1 5 10 15Xaa
Xaa518PRTArtificial SequenceSynthetic IgG binding peptide 5Tyr Asp
Pro Glu Thr Gly Thr Trp Pro Gln Glu Ile Arg Leu Ile Leu1 5 10 15Asn
Trp618PRTArtificial SequenceSynthetic IgG binding peptide 6Tyr Asp
Pro Glu Thr Gly Thr Trp Pro Gln Trp Ile Thr Leu Thr Ile1 5 10 15Thr
Tyr726PRTArtificial SequenceSynthetic IgG binding
peptidemisc_feature(19)..(19)Xaa can be any naturally occurring
amino acidmisc_feature(21)..(21)Xaa can be any naturally occurring
amino acidmisc_feature(23)..(23)Xaa can be any naturally occurring
amino acidmisc_feature(24)..(24)Xaa is Ile or
Leumisc_feature(25)..(25)Xaa is Asn or Thrmisc_feature(26)..(26)Xaa
is Tyr or Trp 7Pro Asn Ser Gly Gly Gly Gly Ser Tyr Asp Pro Glu Thr
Gly Thr Trp1 5 10 15Pro Gln Xaa Ile Xaa Leu Xaa Xaa Xaa Xaa 20
25826PRTArtificial SequenceSynthetic IgG binding peptide 8Pro Asn
Ser Gly Gly Gly Gly Ser Tyr Asp Pro Glu Thr Gly Thr Trp1 5 10 15Pro
Gln Glu Ile Arg Leu Ile Leu Asn Trp 20 25926PRTArtificial
SequenceSynthetic IgG binding peptide 9Pro Asn Ser Gly Gly Gly Gly
Ser Tyr Asp Pro Glu Thr Gly Thr Trp1 5 10 15Pro Gln Trp Ile Thr Leu
Thr Ile Thr Tyr 20 251026PRTArtificial SequenceSynthetic IgG
binding peptide 10Pro Asn Ser Gly Gly Gly Gly Ser Tyr Asp Pro Glu
Thr Gly Thr Trp1 5 10 15Ala Gln Glu Ile Arg Leu Ile Leu Asn Trp 20
251126PRTArtificial SequenceSynthetic IgG binding peptide 11Pro Asn
Ser Gly Gly Gly Gly Ser Tyr Asp Pro Glu Thr Gly Thr Trp1 5 10 15Pro
Ala Glu Ile Arg Leu Ile Leu Asn Trp 20 251226PRTArtificial
SequenceSynthetic IgG binding peptide 12Pro Asn Ser Gly Gly Gly Gly
Ser Tyr Asp Pro Glu Thr Gly Thr Trp1 5 10 15Pro Gln Glu Ile Arg Leu
Ile Ala Asn Trp 20 2513183PRTArtificial SequenceSynthetic IgG
binding peptide 13Met Ser Asp Lys Ile Ile His Leu Thr Asp Asp Ser
Phe Asp Thr Asp1 5 10 15Val Leu Lys Ala Asp Gly Ala Ile Leu Val Asp
Phe Trp Ala Glu Trp 20 25 30Cys Gly Pro Cys Lys Met Ile Ala Pro Ile
Leu Asp Glu Ile Ala Asp 35 40 45Glu Tyr Gln Gly Lys Leu Thr Val Ala
Lys Leu Asn Ile Asp Gln Asn 50 55 60Pro Gly Thr Ala Pro Lys Tyr Gly
Ile Arg Gly Ile Pro Thr Leu Leu65 70 75 80Leu Phe Lys Asn Gly Glu
Val Ala Ala Thr Lys Val Gly Ala Leu Ser 85 90 95Lys Gly Gln Leu Lys
Glu Phe Leu Asp Ala Asn Leu Ala Gly Ser Gly 100 105 110Ser Gly His
Thr Ser Gly Gly Gly Gly Ser Asn Asn Asn Pro Pro Thr 115 120 125Pro
Thr Pro Ser Ser Gly Ser Gly His His His His His His Ser Ala 130 135
140Ala Leu Glu Val Leu Phe Gln Gly Pro Gly Tyr Gln Asp Pro Asn
Ser145 150 155 160Gly Gly Gly Gly Ser Tyr Asp Pro Glu Thr Gly Thr
Trp Pro Gln Ala 165 170 175Gln Lys Lys Glu Ile Gln Thr
18014183PRTArtificial SequenceSynthetic IgG binding peptide 14Met
Ser Asp Lys Ile Ile His Leu Thr Asp Asp Ser Phe Asp Thr Asp1 5 10
15Val Leu Lys Ala Asp Gly Ala Ile Leu Val Asp Phe Trp Ala Glu Trp
20 25 30Cys Gly Pro Cys Lys Met Ile Ala Pro Ile Leu Asp Glu Ile Ala
Asp 35 40 45Glu Tyr Gln Gly Lys Leu Thr Val Ala Lys Leu Asn Ile Asp
Gln Asn 50 55 60Pro Gly Thr Ala Pro Lys Tyr Gly Ile Arg Gly Ile Pro
Thr Leu Leu65 70 75 80Leu Phe Lys Asn Gly Glu Val Ala Ala Thr Lys
Val Gly Ala Leu Ser 85 90 95Lys Gly Gln Leu Lys Glu Phe Leu Asp Ala
Asn Leu Ala Gly Ser Gly 100 105 110Ser Gly His Thr Ser Gly Gly Gly
Gly Ser Asn Asn Asn Pro Pro Thr 115 120 125Pro Thr Pro Ser Ser Gly
Ser Gly His His His His His His Ser Ala 130 135 140Ala Leu Glu Val
Leu Phe Gln Gly Pro Gly Tyr Gln Asp Pro Asn Ser145 150 155 160Gly
Gly Gly Gly Ser Tyr Asp Pro Glu Thr Gly Thr Trp Pro Gln Glu 165 170
175Ile Arg Leu Ile Leu Asn Trp 18015183PRTArtificial
SequenceSynthetic IgG binding peptide 15Met Ser Asp Lys Ile Ile His
Leu Thr Asp Asp Ser Phe Asp Thr Asp1 5 10 15Val Leu Lys Ala Asp Gly
Ala Ile Leu Val Asp Phe Trp Ala Glu Trp 20 25 30Cys Gly Pro Cys Lys
Met Ile Ala Pro Ile Leu Asp Glu Ile Ala Asp 35 40 45Glu Tyr Gln Gly
Lys Leu Thr Val Ala Lys Leu Asn Ile Asp Gln Asn 50 55 60Pro Gly Thr
Ala Pro Lys Tyr Gly Ile Arg Gly Ile Pro Thr Leu Leu65 70 75 80Leu
Phe Lys Asn Gly Glu Val Ala Ala Thr Lys Val Gly Ala Leu Ser 85 90
95Lys Gly Gln Leu Lys Glu Phe Leu Asp Ala Asn Leu Ala Gly Ser Gly
100 105 110Ser Gly His Thr Ser Gly Gly Gly Gly Ser Asn Asn Asn Pro
Pro Thr 115 120 125Pro Thr Pro Ser Ser Gly Ser Gly His His His His
His His Ser Ala 130 135 140Ala Leu Glu Val Leu Phe Gln Gly Pro Gly
Tyr Gln Asp Pro Asn Ser145 150 155 160Gly Gly Gly Gly Ser Tyr Asp
Pro Glu Thr Gly Thr Trp Pro Gln Trp 165 170 175Ile Thr Leu Thr Ile
Thr Tyr 18016549DNAArtificial SequenceSynthetic oligonucleotide
sequence 16atgagcgata aaattattca cctgactgac gacagttttg acacggatgt
actcaaagcg 60gacggggcga tcctcgtcga tttctgggca gagtggtgcg gtccgtgcaa
aatgatcgcc 120ccgattctgg atgaaatcgc tgacgaatat cagggcaaac
tgaccgttgc aaaactgaac 180atcgatcaaa accctggcac tgcgccgaaa
tatggcatcc gtggtatccc gactctgctg 240ctgttcaaaa acggtgaagt
ggcggcaacc aaagtgggtg cactgtctaa aggtcagttg 300aaagagttcc
tcgacgctaa cctggccggt tctggttctg gccatactag tggtggtggc
360ggttctaata acaatcctcc tactcctact ccatctagtg gttctggtca
tcaccatcac 420catcactccg cggctcttga agtcctcttt cagggacccg
ggtaccagga tccgaattcg 480ggaggagggg gatcatacga ccccgagacg
ggcacgtggc cacaagcaca gaaaaaagag 540atacaaaca 54917549DNAArtificial
SequenceSynthetic oligonucleotide sequence 17atgagcgata aaattattca
cctgactgac gacagttttg acacggatgt actcaaagcg 60gacggggcga tcctcgtcga
tttctgggca gagtggtgcg gtccgtgcaa aatgatcgcc 120ccgattctgg
atgaaatcgc tgacgaatat cagggcaaac tgaccgttgc aaaactgaac
180atcgatcaaa accctggcac tgcgccgaaa tatggcatcc gtggtatccc
gactctgctg 240ctgttcaaaa acggtgaagt ggcggcaacc aaagtgggtg
cactgtctaa aggtcagttg 300aaagagttcc tcgacgctaa cctggccggt
tctggttctg gccatactag tggtggtggc 360ggttctaata acaatcctcc
tactcctact ccatctagtg gttctggtca tcaccatcac 420catcactccg
cggctcttga agtcctcttt cagggacccg ggtaccagga tccgaattcg
480ggaggagggg gatcatacga ccccgagacg ggcacgtggc cacaggaaat
tagactaata 540cttaattgg 54918549DNAArtificial SequenceSynthetic
oligonucleotide sequence 18atgagcgata aaattattca cctgactgac
gacagttttg acacggatgt actcaaagcg 60gacggggcga tcctcgtcga tttctgggca
gagtggtgcg gtccgtgcaa aatgatcgcc 120ccgattctgg atgaaatcgc
tgacgaatat cagggcaaac tgaccgttgc aaaactgaac 180atcgatcaaa
accctggcac tgcgccgaaa tatggcatcc gtggtatccc gactctgctg
240ctgttcaaaa acggtgaagt ggcggcaacc aaagtgggtg cactgtctaa
aggtcagttg 300aaagagttcc tcgacgctaa cctggccggt tctggttctg
gccatactag tggtggtggc 360ggttctaata acaatcctcc tactcctact
ccatctagtg gttctggtca tcaccatcac 420catcactccg cggctcttga
agtcctcttt cagggacccg ggtaccagga tccgaattcg 480ggaggagggg
gatcatacga ccccgagacg ggcacgtggc cgcagtggat aactcttacg 540ataacgtat
54919109PRTHomo sapiens 19Met His His His His His His Ser Thr Lys
Gly Pro Ser Val Phe Pro1 5 10 15Leu Ala Pro Ser Ser Lys Ser Thr Ser
Gly Gly Thr Ala Ala Leu Gly 20 25 30Cys Leu Val Lys Asp Tyr Phe Pro
Glu Pro Val Thr Val Ser Trp Asn 35 40 45Ser Gly Ala Leu Thr Ser Gly
Val His Thr Phe Pro Ala Val Leu Gln 50 55 60Ser Ser Gly Leu Tyr Ser
Leu Ser Ser Val Val Thr Val Pro Ser Ser65 70 75 80Ser Leu Gly Thr
Gln Thr Tyr Ile Cys Asn Val Asn His Lys Pro Ser 85 90 95Asn Thr Lys
Val Asp Lys Lys Val Glu Pro Lys Ser Cys 100 10520114PRTHomo sapiens
20Met His His His His His His Lys Arg Thr Val Ala Pro Ser Val Phe1
5 10 15Ile Phe Pro Pro Ser Asp Glu Gln Leu Lys Ser Gly Thr Ala Ser
Val 20 25 30Val Cys Leu Leu Asn Asn Phe Tyr Pro Arg Glu Ala Lys Val
Gln Trp 35 40 45Lys Val Asp Asn Ala Leu Gln Ser Gly Asn Ser Gln Glu
Ser Val Thr 50 55 60Glu Gln Asp Ser Lys Asp Ser Thr Tyr Ser Leu Ser
Ser Thr Leu Thr65 70 75 80Leu Ser Lys Ala Asp Tyr Glu Lys His Lys
Val Tyr Ala Cys Glu Val 85 90 95Thr His Gln Gly Leu Ser Ser Pro Val
Thr Lys Ser Phe Asn Arg Gly 100 105 110Glu Cys2123PRTArtificial
SequenceSynthetic peptide librarymisc_feature(14)..(23)Xaa can be
any naturally occurring amino acid 21Gly Gly Gly Gly Ser Tyr Asp
Pro Glu Thr Gly Thr Trp Xaa Xaa Xaa1 5 10 15Xaa Xaa Xaa Xaa Xaa Xaa
Xaa 202221PRTArtificial SequenceSynthetic peptide
librarymisc_feature(14)..(21)Xaa can be any naturally occurring
amino acid 22Gly Gly Gly Gly Ser Tyr Asp Pro Glu Thr Gly Thr Trp
Xaa Xaa Xaa1 5 10 15Xaa Xaa Xaa Xaa Xaa 202324PRTArtificial
SequenceSynthetic peptide librarymisc_feature(16)..(24)Xaa can be
any naturally occurring amino acid 23Gly Gly Gly Gly Ser Tyr Tyr
Asp Pro Glu Thr Gly Thr Trp Tyr Xaa1 5 10 15Xaa Xaa Xaa Xaa Xaa Xaa
Xaa Xaa 202423PRTArtificial SequenceSynthetic peptide
librarymisc_feature(16)..(23)Xaa can be any naturally occurring
amino acid 24Gly Gly Gly Gly Ser Tyr Tyr Asp Pro Glu Thr Gly Thr
Trp Tyr Xaa1 5 10 15Xaa Xaa Xaa Xaa Xaa Xaa Xaa 202569DNAArtificial
SequenceSynthetic oligonucleotide sequencemisc_feature(40)..(41)n
is a, c, g, or tmisc_feature(42)..(42)k is g or
tmisc_feature(43)..(44)n is a, c, g, or tmisc_feature(45)..(45)k is
g or tmisc_feature(46)..(47)n is a, c, g, or
tmisc_feature(48)..(48)k is g or tmisc_feature(49)..(50)n is a, c,
g, or tmisc_feature(51)..(51)k is g or tmisc_feature(52)..(53)n is
a, c, g, or tmisc_feature(54)..(54)k is g or
tmisc_feature(55)..(56)n is a, c, g, or tmisc_feature(57)..(57)k is
g or tmisc_feature(58)..(59)n is a, c, g, or
tmisc_feature(60)..(60)k is g or tmisc_feature(61)..(62)n is a, c,
g, or tmisc_feature(63)..(63)k is g or tmisc_feature(64)..(65)n is
a, c, g, or tmisc_feature(66)..(66)k is g or
tmisc_feature(67)..(68)n is a, c, g, or tmisc_feature(69)..(69)k is
g or t 25ggaggagggg gatcatacga ccccgagacg ggcacgtggn nknnknnknn
knnknnknnk 60nnknnknnk 692663DNAArtificial SequenceSynthetic
oligonucleotide sequencemisc_feature(40)..(41)n is a, c, g, or
tmisc_feature(42)..(42)k is g or tmisc_feature(43)..(44)n is a, c,
g, or tmisc_feature(45)..(45)k is g or tmisc_feature(46)..(47)n is
a, c, g, or tmisc_feature(48)..(48)k is g or
tmisc_feature(49)..(50)n is a, c, g, or tmisc_feature(51)..(51)k is
g or tmisc_feature(52)..(53)n is a, c, g, or
tmisc_feature(54)..(54)k is g or tmisc_feature(55)..(56)n is a, c,
g, or tmisc_feature(57)..(57)k is g or tmisc_feature(58)..(59)n is
a, c, g, or tmisc_feature(60)..(60)k is g or
tmisc_feature(61)..(62)n is a, c, g, or tmisc_feature(63)..(63)k is
g or t 26ggaggagggg gatcatacga ccccgagacg ggcacgtggn nknnknnknn
knnknnknnk 60nnk 632775DNAArtificial SequenceSynthetic
oligonucleotide sequencemisc_feature(46)..(47)n is a, c, g, or
tmisc_feature(48)..(48)k is g or tmisc_feature(49)..(50)n is a, c,
g, or tmisc_feature(51)..(51)k is g or tmisc_feature(52)..(53)n is
a, c, g, or tmisc_feature(54)..(54)k is g or
tmisc_feature(55)..(56)n is a, c, g, or tmisc_feature(57)..(57)k is
g or tmisc_feature(58)..(59)n is a, c, g, or
tmisc_feature(60)..(60)k is g or tmisc_feature(61)..(62)n is a, c,
g, or tmisc_feature(63)..(63)k is g or tmisc_feature(64)..(65)n is
a, c, g, or tmisc_feature(66)..(66)k is g or
tmisc_feature(67)..(68)n is a, c, g, or tmisc_feature(69)..(69)k is
g or tmisc_feature(70)..(71)n is a, c, g, or
tmisc_feature(72)..(72)k is g or tmisc_feature(73)..(74)n is a, c,
g, or tmisc_feature(75)..(75)k is g or t 27ggaggagggg gatcatacta
tgaccccgag acgggcacgt ggtatnnknn knnknnknnk 60nnknnknnkn nknnk
752869DNAArtificial SequenceSynthetic oligonucleotide
sequencemisc_feature(46)..(47)n is a, c, g, or
tmisc_feature(48)..(48)k is g or tmisc_feature(49)..(50)n is a, c,
g, or tmisc_feature(51)..(51)k is g or tmisc_feature(52)..(53)n is
a, c, g, or tmisc_feature(54)..(54)k is g or
tmisc_feature(55)..(56)n is a, c, g, or tmisc_feature(57)..(57)k is
g or tmisc_feature(58)..(59)n is a, c, g, or
tmisc_feature(60)..(60)k is g or tmisc_feature(61)..(62)n is a, c,
g, or tmisc_feature(63)..(63)k is g or tmisc_feature(64)..(65)n is
a, c, g, or tmisc_feature(66)..(66)k is g or
tmisc_feature(67)..(68)n is a, c, g, or tmisc_feature(69)..(69)k is
g or t 28ggaggagggg gatcatacta tgaccccgag acgggcacgt ggtatnnknn
knnknnknnk 60nnknnknnk 6929157PRTEscherichia coli 29Met Ser Asp Lys
Ile Ile His Leu Thr Asp Asp Ser Phe Asp Thr Asp1 5 10 15Val Leu Lys
Ala Asp Gly Ala Ile Leu Val Asp Phe Trp Ala Glu Trp 20 25 30Cys Gly
Pro Cys Lys Met Ile Ala Pro Ile Leu Asp Glu Ile Ala Asp 35 40 45Glu
Tyr Gln Gly Lys Leu Thr Val Ala Lys Leu Asn Ile Asp Gln Asn 50 55
60Pro Gly Thr Ala Pro Lys Tyr Gly Ile Arg Gly Ile Pro Thr Leu Leu65
70 75 80Leu Phe Lys Asn Gly Glu Val Ala Ala Thr Lys Val Gly Ala Leu
Ser 85 90 95Lys Gly Gln Leu Lys Glu Phe Leu Asp Ala Asn Leu Ala Gly
Ser Gly 100 105 110Ser Gly His Thr Ser Gly Gly Gly Gly Ser Asn Asn
Asn Pro Pro Thr 115 120 125Pro Thr Pro Ser Ser Gly Ser Gly His His
His His His His Ser Ala 130 135 140Ala Leu Glu Val Leu Phe Gln Gly
Pro Gly Tyr Gln Asp145 150 155308PRTArtificial Sequencesynthetic
peptide 30Pro Asn Ser Gly Gly Gly Gly Ser1 5318PRTArtificial
Sequencesynthetic peptide 31Tyr Asp Pro Glu Thr Gly Thr Trp1
53210PRTArtificial SequenceSynthetic IgG binding peptide 32Pro Gln
Ala Gln Lys Lys Glu Ile Gln Thr1 5 103316PRTArtificial
Sequencesynthetic peptide 33Pro Asn Ser Gly Gly Gly Gly Ser Tyr Asp
Pro Glu Thr Gly Thr Trp1 5 10 153428PRTArtificial SequenceSynthetic
peptide librarymisc_feature(1)..(10)Xaa can be any naturally
occurring amino acid
34Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Xaa Tyr Asp Pro Glu Thr Gly1
5 10 15Thr Trp Pro Gln Glu Ile Arg Leu Ile Leu Asn Trp 20
253584DNAArtificial SequenceSynthetic olignucleotide
sequencemisc_feature(1)..(2)n is a, c, g, or tmisc_feature(3)..(3)k
is g or tmisc_feature(4)..(5)n is a, c, g, or
tmisc_feature(6)..(6)k is g or tmisc_feature(7)..(8)n is a, c, g,
or tmisc_feature(9)..(9)k is g or tmisc_feature(10)..(11)n is a, c,
g, or tmisc_feature(12)..(12)k is g or tmisc_feature(13)..(14)n is
a, c, g, or tmisc_feature(15)..(15)k is g or
tmisc_feature(16)..(17)n is a, c, g, or tmisc_feature(18)..(18)k is
g or tmisc_feature(19)..(20)n is a, c, g, or
tmisc_feature(21)..(21)k is g or tmisc_feature(22)..(23)n is a, c,
g, or tmisc_feature(24)..(24)k is g or tmisc_feature(25)..(26)n is
a, c, g, or tmisc_feature(27)..(27)k is g or
tmisc_feature(28)..(29)n is a, c, g, or tmisc_feature(30)..(30)k is
g or t 35nnknnknnkn nknnknnknn knnknnknnk tacgaccccg agacgggcac
gtggccgcag 60gaaattcgcc tgattctgaa ctgg 843628PRTArtificial
SequenceSynthetic IgG binding peptide 36His Asn Phe Thr Leu Pro Leu
Trp Met Tyr Tyr Asp Pro Glu Thr Gly1 5 10 15Thr Trp Pro Gln Glu Ile
Arg Leu Ile Leu Asn Trp 20 253728PRTArtificial SequenceSynthetic
IgG binding peptide 37Arg Phe Pro Leu Met Phe Gly Pro Ser Trp Tyr
Asp Pro Glu Thr Gly1 5 10 15Thr Trp Pro Gln Glu Ile Arg Leu Ile Leu
Asn Trp 20 253828PRTArtificial SequenceSynthetic IgG binding
peptide 38Arg Phe Tyr Val Leu Leu Asp Ser Ser Trp Tyr Asp Pro Glu
Thr Gly1 5 10 15Thr Trp Pro Gln Glu Ile Arg Leu Ile Leu Asn Trp 20
253928PRTArtificial SequenceSynthetic IgG binding peptide 39Val Ser
Lys Phe Tyr Pro Leu Trp Thr Arg Tyr Asp Pro Glu Thr Gly1 5 10 15Thr
Trp Pro Gln Glu Ile Arg Leu Ile Leu Asn Trp 20 254028PRTArtificial
SequenceSynthetic IgG binding peptide 40Val Phe Leu Val Leu Met Gly
Pro Glu Phe Tyr Asp Pro Glu Thr Gly1 5 10 15Thr Trp Pro Gln Glu Ile
Arg Leu Ile Leu Asn Trp 20 254128PRTArtificial SequenceSynthetic
IgG binding peptide 41Phe Leu Leu Phe Cys Pro Arg Ser Leu Cys Tyr
Asp Pro Glu Thr Gly1 5 10 15Thr Trp Pro Gln Glu Ile Arg Leu Ile Leu
Asn Trp 20 2542193PRTArtificial SequenceSynthetic IgG binding
peptide 42Met Ser Asp Lys Ile Ile His Leu Thr Asp Asp Ser Phe Asp
Thr Asp1 5 10 15Val Leu Lys Ala Asp Gly Ala Ile Leu Val Asp Phe Trp
Ala Glu Trp 20 25 30Cys Gly Pro Cys Lys Met Ile Ala Pro Ile Leu Asp
Glu Ile Ala Asp 35 40 45Glu Tyr Gln Gly Lys Leu Thr Val Ala Lys Leu
Asn Ile Asp Gln Asn 50 55 60Pro Gly Thr Ala Pro Lys Tyr Gly Ile Arg
Gly Ile Pro Thr Leu Leu65 70 75 80Leu Phe Lys Asn Gly Glu Val Ala
Ala Thr Lys Val Gly Ala Leu Ser 85 90 95Lys Gly Gln Leu Lys Glu Phe
Leu Asp Ala Asn Leu Ala Gly Ser Gly 100 105 110Ser Gly His Thr Ser
Gly Gly Gly Gly Ser Asn Asn Asn Pro Pro Thr 115 120 125Pro Thr Pro
Ser Ser Gly Ser Gly His His His His His His Ser Ala 130 135 140Ala
Leu Glu Val Leu Phe Gln Gly Pro Gly Tyr Gln Asp Pro Asn Ser145 150
155 160Gly Gly Gly Gly Ser His Asn Phe Thr Leu Pro Leu Trp Met Tyr
Tyr 165 170 175Asp Pro Glu Thr Gly Thr Trp Pro Gln Glu Ile Arg Leu
Ile Leu Asn 180 185 190Trp43193PRTArtificial SequenceSynthetic IgG
binding peptide 43Met Ser Asp Lys Ile Ile His Leu Thr Asp Asp Ser
Phe Asp Thr Asp1 5 10 15Val Leu Lys Ala Asp Gly Ala Ile Leu Val Asp
Phe Trp Ala Glu Trp 20 25 30Cys Gly Pro Cys Lys Met Ile Ala Pro Ile
Leu Asp Glu Ile Ala Asp 35 40 45Glu Tyr Gln Gly Lys Leu Thr Val Ala
Lys Leu Asn Ile Asp Gln Asn 50 55 60Pro Gly Thr Ala Pro Lys Tyr Gly
Ile Arg Gly Ile Pro Thr Leu Leu65 70 75 80Leu Phe Lys Asn Gly Glu
Val Ala Ala Thr Lys Val Gly Ala Leu Ser 85 90 95Lys Gly Gln Leu Lys
Glu Phe Leu Asp Ala Asn Leu Ala Gly Ser Gly 100 105 110Ser Gly His
Thr Ser Gly Gly Gly Gly Ser Asn Asn Asn Pro Pro Thr 115 120 125Pro
Thr Pro Ser Ser Gly Ser Gly His His His His His His Ser Ala 130 135
140Ala Leu Glu Val Leu Phe Gln Gly Pro Gly Tyr Gln Asp Pro Asn
Ser145 150 155 160Gly Gly Gly Gly Ser Arg Phe Pro Leu Met Phe Gly
Pro Ser Trp Tyr 165 170 175Asp Pro Glu Thr Gly Thr Trp Pro Gln Glu
Ile Arg Leu Ile Leu Asn 180 185 190Trp44193PRTArtificial
SequenceSynthetic IgG binding peptide 44Met Ser Asp Lys Ile Ile His
Leu Thr Asp Asp Ser Phe Asp Thr Asp1 5 10 15Val Leu Lys Ala Asp Gly
Ala Ile Leu Val Asp Phe Trp Ala Glu Trp 20 25 30Cys Gly Pro Cys Lys
Met Ile Ala Pro Ile Leu Asp Glu Ile Ala Asp 35 40 45Glu Tyr Gln Gly
Lys Leu Thr Val Ala Lys Leu Asn Ile Asp Gln Asn 50 55 60Pro Gly Thr
Ala Pro Lys Tyr Gly Ile Arg Gly Ile Pro Thr Leu Leu65 70 75 80Leu
Phe Lys Asn Gly Glu Val Ala Ala Thr Lys Val Gly Ala Leu Ser 85 90
95Lys Gly Gln Leu Lys Glu Phe Leu Asp Ala Asn Leu Ala Gly Ser Gly
100 105 110Ser Gly His Thr Ser Gly Gly Gly Gly Ser Asn Asn Asn Pro
Pro Thr 115 120 125Pro Thr Pro Ser Ser Gly Ser Gly His His His His
His His Ser Ala 130 135 140Ala Leu Glu Val Leu Phe Gln Gly Pro Gly
Tyr Gln Asp Pro Asn Ser145 150 155 160Gly Gly Gly Gly Ser Arg Phe
Tyr Val Leu Leu Asp Ser Ser Trp Tyr 165 170 175Asp Pro Glu Thr Gly
Thr Trp Pro Gln Glu Ile Arg Leu Ile Leu Asn 180 185
190Trp45193PRTArtificial SequenceSynthetic IgG binding peptide
45Met Ser Asp Lys Ile Ile His Leu Thr Asp Asp Ser Phe Asp Thr Asp1
5 10 15Val Leu Lys Ala Asp Gly Ala Ile Leu Val Asp Phe Trp Ala Glu
Trp 20 25 30Cys Gly Pro Cys Lys Met Ile Ala Pro Ile Leu Asp Glu Ile
Ala Asp 35 40 45Glu Tyr Gln Gly Lys Leu Thr Val Ala Lys Leu Asn Ile
Asp Gln Asn 50 55 60Pro Gly Thr Ala Pro Lys Tyr Gly Ile Arg Gly Ile
Pro Thr Leu Leu65 70 75 80Leu Phe Lys Asn Gly Glu Val Ala Ala Thr
Lys Val Gly Ala Leu Ser 85 90 95Lys Gly Gln Leu Lys Glu Phe Leu Asp
Ala Asn Leu Ala Gly Ser Gly 100 105 110Ser Gly His Thr Ser Gly Gly
Gly Gly Ser Asn Asn Asn Pro Pro Thr 115 120 125Pro Thr Pro Ser Ser
Gly Ser Gly His His His His His His Ser Ala 130 135 140Ala Leu Glu
Val Leu Phe Gln Gly Pro Gly Tyr Gln Asp Pro Asn Ser145 150 155
160Gly Gly Gly Gly Ser Val Ser Lys Phe Tyr Pro Leu Trp Thr Arg Tyr
165 170 175Asp Pro Glu Thr Gly Thr Trp Pro Gln Glu Ile Arg Leu Ile
Leu Asn 180 185 190Trp46193PRTArtificial SequenceSynthetic IgG
binding peptide 46Met Ser Asp Lys Ile Ile His Leu Thr Asp Asp Ser
Phe Asp Thr Asp1 5 10 15Val Leu Lys Ala Asp Gly Ala Ile Leu Val Asp
Phe Trp Ala Glu Trp 20 25 30Cys Gly Pro Cys Lys Met Ile Ala Pro Ile
Leu Asp Glu Ile Ala Asp 35 40 45Glu Tyr Gln Gly Lys Leu Thr Val Ala
Lys Leu Asn Ile Asp Gln Asn 50 55 60Pro Gly Thr Ala Pro Lys Tyr Gly
Ile Arg Gly Ile Pro Thr Leu Leu65 70 75 80Leu Phe Lys Asn Gly Glu
Val Ala Ala Thr Lys Val Gly Ala Leu Ser 85 90 95Lys Gly Gln Leu Lys
Glu Phe Leu Asp Ala Asn Leu Ala Gly Ser Gly 100 105 110Ser Gly His
Thr Ser Gly Gly Gly Gly Ser Asn Asn Asn Pro Pro Thr 115 120 125Pro
Thr Pro Ser Ser Gly Ser Gly His His His His His His Ser Ala 130 135
140Ala Leu Glu Val Leu Phe Gln Gly Pro Gly Tyr Gln Asp Pro Asn
Ser145 150 155 160Gly Gly Gly Gly Ser Val Phe Leu Val Leu Met Gly
Pro Glu Phe Tyr 165 170 175Asp Pro Glu Thr Gly Thr Trp Pro Gln Glu
Ile Arg Leu Ile Leu Asn 180 185 190Trp47579DNAArtificial
SequenceSynthetic oligonucleotide sequence 47atgagcgata aaattattca
cctgactgac gacagttttg acacggatgt actcaaagcg 60gacggggcga tcctcgtcga
tttctgggca gagtggtgcg gtccgtgcaa aatgatcgcc 120ccgattctgg
atgaaatcgc tgacgaatat cagggcaaac tgaccgttgc aaaactgaac
180atcgatcaaa accctggcac tgcgccgaaa tatggcatcc gtggtatccc
gactctgctg 240ctgttcaaaa acggtgaagt ggcggcaacc aaagtgggtg
cactgtctaa aggtcagttg 300aaagagttcc tcgacgctaa cctggccggt
tctggttctg gccatactag tggtggtggc 360ggttctaata acaatcctcc
tactcctact ccatctagtg gttctggtca tcaccatcac 420catcactccg
cggctcttga agtcctcttt cagggacccg ggtaccagga tccgaattcg
480ggaggagggg gatcacataa ttttactctt cctctgtgga tgtattacga
ccccgagacg 540ggcacgtggc cgcaggaaat tcgcctgatt ctgaactgg
57948579DNAArtificial SequenceSynthetic oligonucleotide sequence
48atgagcgata aaattattca cctgactgac gacagttttg acacggatgt actcaaagcg
60gacggggcga tcctcgtcga tttctgggca gagtggtgcg gtccgtgcaa aatgatcgcc
120ccgattctgg atgaaatcgc tgacgaatat cagggcaaac tgaccgttgc
aaaactgaac 180atcgatcaaa accctggcac tgcgccgaaa tatggcatcc
gtggtatccc gactctgctg 240ctgttcaaaa acggtgaagt ggcggcaacc
aaagtgggtg cactgtctaa aggtcagttg 300aaagagttcc tcgacgctaa
cctggccggt tctggttctg gccatactag tggtggtggc 360ggttctaata
acaatcctcc tactcctact ccatctagtg gttctggtca tcaccatcac
420catcactccg cggctcttga agtcctcttt cagggacccg ggtaccagga
tccgaattcg 480ggaggagggg gatcacgttt tccgttgatg tttgggccgt
cttggtacga ccccgagacg 540ggcacgtggc cgcaggaaat tcgcctgatt ctgaactgg
57949579DNAArtificial SequenceSynthetic oligonucleotide sequence
49atgagcgata aaattattca cctgactgac gacagttttg acacggatgt actcaaagcg
60gacggggcga tcctcgtcga tttctgggca gagtggtgcg gtccgtgcaa aatgatcgcc
120ccgattctgg atgaaatcgc tgacgaatat cagggcaaac tgaccgttgc
aaaactgaac 180atcgatcaaa accctggcac tgcgccgaaa tatggcatcc
gtggtatccc gactctgctg 240ctgttcaaaa acggtgaagt ggcggcaacc
aaagtgggtg cactgtctaa aggtcagttg 300aaagagttcc tcgacgctaa
cctggccggt tctggttctg gccatactag tggtggtggc 360ggttctaata
acaatcctcc tactcctact ccatctagtg gttctggtca tcaccatcac
420catcactccg cggctcttga agtcctcttt cagggacccg ggtaccagga
tccgaattcg 480ggaggagggg gatcacggtt ttatgttctg ctggattctt
cttggtacga ccccgagacg 540ggcacgtggc cgcaggaaat tcgcctgatt ctgaactgg
57950579DNAArtificial SequenceSynthetic oligonucleotide sequence
50atgagcgata aaattattca cctgactgac gacagttttg acacggatgt actcaaagcg
60gacggggcga tcctcgtcga tttctgggca gagtggtgcg gtccgtgcaa aatgatcgcc
120ccgattctgg atgaaatcgc tgacgaatat cagggcaaac tgaccgttgc
aaaactgaac 180atcgatcaaa accctggcac tgcgccgaaa tatggcatcc
gtggtatccc gactctgctg 240ctgttcaaaa acggtgaagt ggcggcaacc
aaagtgggtg cactgtctaa aggtcagttg 300aaagagttcc tcgacgctaa
cctggccggt tctggttctg gccatactag tggtggtggc 360ggttctaata
acaatcctcc tactcctact ccatctagtg gttctggtca tcaccatcac
420catcactccg cggctcttga agtcctcttt cagggacccg ggtaccagga
tccgaattcg 480ggaggagggg gatcagtgag taagttttat ccgctgtgga
cgcggtacga ccccgagacg 540ggcacgtggc cgcaggaaat tcgcctgatt ctgaactgg
57951579DNAArtificial SequenceSynthetic oligonucleotide sequence
51atgagcgata aaattattca cctgactgac gacagttttg acacggatgt actcaaagcg
60gacggggcga tcctcgtcga tttctgggca gagtggtgcg gtccgtgcaa aatgatcgcc
120ccgattctgg atgaaatcgc tgacgaatat cagggcaaac tgaccgttgc
aaaactgaac 180atcgatcaaa accctggcac tgcgccgaaa tatggcatcc
gtggtatccc gactctgctg 240ctgttcaaaa acggtgaagt ggcggcaacc
aaagtgggtg cactgtctaa aggtcagttg 300aaagagttcc tcgacgctaa
cctggccggt tctggttctg gccatactag tggtggtggc 360ggttctaata
acaatcctcc tactcctact ccatctagtg gttctggtca tcaccatcac
420catcactccg cggctcttga agtcctcttt cagggacccg ggtaccagga
tccgaattcg 480ggaggagggg gatcagtgtt tcttgttttg atggggcctg
agttttacga ccccgagacg 540ggcacgtggc cgcaggaaat tcgcctgatt ctgaactgg
579
* * * * *