4mnq

TCR-peptide specificity overrides affinity enhancing TCR-MHC interactions

Method: X-RAY DIFFRACTION

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1. Protein Identity and Related Structures Protein Identity & Related Structures

HLA class I histocompatibility antigen, A-2 alpha chain

Homo sapiens

State in the Current Structure

Assembly	Physical composition	Protein state	Molecular copy count	Associated components	Data consistency
1	Insufficient information	Heteromer	Protein 5	Beta-2-microglobulin × 1 （P61769） Telomerase reverse transcriptase × 1 （O14746） Uncharacterized protein, T-cell receptor, sp3.4 alpha chain × 1 （H2RG00,K7N5M9） V_segment translation product, T-cell receptor beta-1 chain C region × 1 （A0A585,P01850） GLYCEROL × 1 1,2-ETHANEDIOL × 2 water × 4	Consistent with protein count

Other States of the Same Protein in the Database

View Construct and Data Evidence

UniProt name	1A02_HUMAN
Isoform	—
PDB entities	1
Chains and sequence ranges	Author chain A； PDBConstruct 1–276； UniProt 25–300

Beta-2-microglobulin

Homo sapiens

UniProt P61769

State in the Current Structure

Assembly	Physical composition	Protein state	Molecular copy count	Associated components	Data consistency
1	Insufficient information	Heteromer	Protein 5	HLA class I histocompatibility antigen, A-2 alpha chain × 1 （P01892） Telomerase reverse transcriptase × 1 （O14746） Uncharacterized protein, T-cell receptor, sp3.4 alpha chain × 1 （H2RG00,K7N5M9） V_segment translation product, T-cell receptor beta-1 chain C region × 1 （A0A585,P01850） GLYCEROL × 1 1,2-ETHANEDIOL × 2 water × 4	Consistent with protein count

Other States of the Same Protein in the Database

View Construct and Data Evidence

UniProt name	B2MG_HUMAN
Isoform	—
PDB entities	2
Chains and sequence ranges	Author chain B； PDBConstruct 2–100； UniProt 21–119

Telomerase reverse transcriptase

OrganismNot specified

UniProt O14746

State in the Current Structure

Assembly	Physical composition	Protein state	Molecular copy count	Associated components	Data consistency
1	Insufficient information	Heteromer	Protein 5	HLA class I histocompatibility antigen, A-2 alpha chain × 1 （P01892） Beta-2-microglobulin × 1 （P61769） Uncharacterized protein, T-cell receptor, sp3.4 alpha chain × 1 （H2RG00,K7N5M9） V_segment translation product, T-cell receptor beta-1 chain C region × 1 （A0A585,P01850） GLYCEROL × 1 1,2-ETHANEDIOL × 2 water × 4	Consistent with protein count

Other States of the Same Protein in the Database

View Construct and Data Evidence

UniProt name	TERT_HUMAN
Isoform	—
PDB entities	3
Chains and sequence ranges	Author chain C； PDBConstruct 1–9； UniProt 540–548

Uncharacterized protein, T-cell receptor, sp3.4 alpha chain

Homo sapiens

UniProt H2RG00

State in the Current Structure

Assembly	Physical composition	Protein state	Molecular copy count	Associated components	Data consistency
1	Insufficient information	Heteromer	Protein 5	HLA class I histocompatibility antigen, A-2 alpha chain × 1 （P01892） Beta-2-microglobulin × 1 （P61769） Telomerase reverse transcriptase × 1 （O14746） V_segment translation product, T-cell receptor beta-1 chain C region × 1 （A0A585,P01850） GLYCEROL × 1 1,2-ETHANEDIOL × 2 water × 4	Consistent with protein count

Other States of the Same Protein in the Database

View Construct and Data Evidence

UniProt name	H2RG00_PANTR
Isoform	—
PDB entities	4
Chains and sequence ranges	Author chain D； PDBConstruct 1–87； UniProt 17–103

Uncharacterized protein, T-cell receptor, sp3.4 alpha chain

Homo sapiens

UniProt K7N5M9

State in the Current Structure

Assembly	Physical composition	Protein state	Molecular copy count	Associated components	Data consistency
1	Insufficient information	Heteromer	Protein 5	HLA class I histocompatibility antigen, A-2 alpha chain × 1 （P01892） Beta-2-microglobulin × 1 （P61769） Telomerase reverse transcriptase × 1 （O14746） V_segment translation product, T-cell receptor beta-1 chain C region × 1 （A0A585,P01850） GLYCEROL × 1 1,2-ETHANEDIOL × 2 water × 4	Consistent with protein count

Other States of the Same Protein in the Database

View Construct and Data Evidence

UniProt name	K7N5M9_HUMAN
Isoform	—
PDB entities	4
Chains and sequence ranges	Author chain D； PDBConstruct 112–200； UniProt 115–203

V_segment translation product, T-cell receptor beta-1 chain C region

Homo sapiens

UniProt A0A585

State in the Current Structure

Assembly	Physical composition	Protein state	Molecular copy count	Associated components	Data consistency
1	Insufficient information	Heteromer	Protein 5	HLA class I histocompatibility antigen, A-2 alpha chain × 1 （P01892） Beta-2-microglobulin × 1 （P61769） Telomerase reverse transcriptase × 1 （O14746） Uncharacterized protein, T-cell receptor, sp3.4 alpha chain × 1 （H2RG00,K7N5M9） GLYCEROL × 1 1,2-ETHANEDIOL × 2 water × 4	Consistent with protein count

Other States of the Same Protein in the Database

View Construct and Data Evidence

UniProt name	A0A585_HUMAN
Isoform	—
PDB entities	5
Chains and sequence ranges	Author chain E； PDBConstruct 1–94； UniProt 21–114

V_segment translation product, T-cell receptor beta-1 chain C region

Homo sapiens

UniProt P01850

State in the Current Structure

Assembly	Physical composition	Protein state	Molecular copy count	Associated components	Data consistency
1	Insufficient information	Heteromer	Protein 5	HLA class I histocompatibility antigen, A-2 alpha chain × 1 （P01892） Beta-2-microglobulin × 1 （P61769） Telomerase reverse transcriptase × 1 （O14746） Uncharacterized protein, T-cell receptor, sp3.4 alpha chain × 1 （H2RG00,K7N5M9） GLYCEROL × 1 1,2-ETHANEDIOL × 2 water × 4	Consistent with protein count

Other States of the Same Protein in the Database

View Construct and Data Evidence

UniProt name	TRBC1_HUMAN
Isoform	—
PDB entities	5
Chains and sequence ranges	Author chain E； PDBConstruct 112–240； UniProt 2–130

The page prioritizes protein identity, the current assembly, associated components, oligomeric state and cross-PDB links. Chain mapping and sequence ranges are retained as data evidence. Internal IDs, import timestamps and assembly operation expressions are maintenance fields and are not shown here.

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2. Structure Basics 2. Structure Basics

Entry ID entry_id	4mnq
Deposition date deposition_date	2013-09-11
Structure title title	TCR-peptide specificity overrides affinity enhancing TCR-MHC interactions
Keywords keywords	;Surface plasmon resonance (SPR); BIAcoreTM; peptide-major histocompatibility complex (pMHC): T-cell receptor (TCR), T-cells; high affinity TCR, two-step binding, adoptive therapy, Immunoglobulin, Adaptive immune response, IMMUNE SYSTEM ;; IMMUNE SYSTEM
Experimental Method method	X-RAY DIFFRACTION

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3. Official assembly/model SAXS Official SAXS Profiles

This page reads only the latest assembly calculations. Every curve maps to an explicit PDB entry, official biological assembly and coordinate model.

4mnq__assembly_1__model_1

Assembly 1 · Model 1 · CRYSOL 4.1.3-1-20251215 (887e7ef)

Download this curve (.dat)

4mnq__assembly_1__model_1 | I(q)

100 plotted points; both axes use logarithmic scales.

4mnq__assembly_1__model_1 | P(r) · Pending

P(r) will be calculated and displayed separately for the same assembly/model.

Rg（Guinier）	37.30 Å
Rg (electron density)	37.43 Å
Total Rg	37.63 Å
Atom count	6663
Residues	825
Excluded volume	116760 Å³
Maximum q	0.500 Å⁻¹

Assembly	Model	Structure unit	Oligomeric description	Status	CRYSOL	Actions
1	1	`4mnq__assembly_1__model_1`	pentameric （5）	Success	4.1.3-1-20251215 (887e7ef)	View Download

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4. Crystallography and Experiment 4. Crystallography & Experiment

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5. Entities and Polymers Entities & Polymers (8)

Entity 1 Entity 1 polymer

Description description	HLA class I histocompatibility antigen, A-2 alpha chain
Molecular weight formula_weight	31951.3 kDa
Source method src_method	man
Copy count entity_count	1

Polymer Polymer

Polymer type type	polypeptide(L)
Chain IDs strand_id	A
Atom count atom_count	6684

GSHSMRYFFTSVSRPGRGEPRFIAVGYVDDTQFVRFDSDAASQRMEPRAPWIEQEGPEYWDGETRKVKAHSQTHRVDLGTLRGYYNQSEAGSHTVQRMYGCDVGSDWRFLRGYHQYAYDGKDYIALKEDLRSWTAADMAAQTTKHKWEAAHVAEQLRAYLEGTCVEWLRRYLENGKETLQRTDAPKTHMTHHAVSDHEATLRCWALSFYPAEITLTWQRDGEDQTQDTELVETRPAGDGTFQKWAAVVVPSGQEQRYTCHVQHEGLPKPLTLRWEP

Source Source

Source organism organism	Homo sapiens
Common name common_name	human
NCBI taxonomy ID ncbi_taxonomy_id	9606
Host organism host_organism	Escherichia coli

Entity 2 Entity 2 polymer

Description description	Beta-2-microglobulin
Molecular weight formula_weight	11879.4 kDa
Source method src_method	man
Copy count entity_count	1

Polymer Polymer

Polymer type type	polypeptide(L)
Chain IDs strand_id	B

MIQRTPKIQVYSRHPAENGKSNFLNCYVSGFHPSDIEVDLLKNGERIEKVEHSDLSFSKDWSFYLLYYTEFTPTEKDEYACRVNHVTLSQPKIVKWDRDM

Source Source

Source organism organism	Homo sapiens
Common name common_name	human
NCBI taxonomy ID ncbi_taxonomy_id	9606
Host organism host_organism	Escherichia coli

Entity 3 Entity 3 polymer

Description description	Telomerase reverse transcriptase
Molecular weight formula_weight	1142.4 kDa
EC 编号 ec_number	2.7.7.49
Source method src_method	syn
Copy count entity_count	1

Polymer Polymer

Polymer type type	polypeptide(L)
Chain IDs strand_id	C

ILAKFLHWL

Entity 4 Entity 4 polymer

Description description	Uncharacterized protein, T-cell receptor, sp3.4 alpha chain
Molecular weight formula_weight	22245.6 kDa
Source method src_method	man
Copy count entity_count	1

Polymer Polymer

Polymer type type	polypeptide(L)
Chain IDs strand_id	D

IQVEQSPPDLILQEGANSTLRCNFSDSVNNLWWFHQNPWGQLINLFYIPSGTKQNGRLSATTVATERYSLLYISSSQTTDSGVYFCAVDSATALPYGYIFGTGTRLKVLANIQNPDPAVYQLRDSKSSDKSVCLFTDFDSQTNVSQSKDSDVYITDKCVLDMRSMDFKSNSAVAWSNKSDFACANAFNNSIIPEDTFFPS

Source Source

Source organism organism	Homo sapiens
Common name common_name	Chimpanzee, human
NCBI taxonomy ID ncbi_taxonomy_id	9606
Host organism host_organism	Escherichia coli

Entity 5 Entity 5 polymer

Description description	V_segment translation product, T-cell receptor beta-1 chain C region
Molecular weight formula_weight	27135.1 kDa
Source method src_method	man
Copy count entity_count	1

Polymer Polymer

Polymer type type	polypeptide(L)
Chain IDs strand_id	E

AGVTQTPKFQVLKTGQSMTLQCAQDMNHEYMSWYRQDPGMGLRLIHYSIHPEYTDQGEVPNGYNVSRSTTEDFPLRLLSAAPSQTSVYFCASSYQGTEAFFGQGTRLTVVEDLNKVFPPEVAVFEPSEAEISHTQKATLVCLATGFYPDHVELSWWVNGKEVHSGVCTDPQPLKEQPALNDSRYALSSRLRVSATFWQDPRNHFRCQVQFYGLSENDEWTQDRAKPVTQIVSAEAWGRAD

Source Source

Source organism organism	Homo sapiens
Common name common_name	human
NCBI taxonomy ID ncbi_taxonomy_id	9606
Host organism host_organism	Escherichia coli

Entity 6 Entity 6 non-polymer

Description description	GLYCEROL
Molecular weight formula_weight	92.1 kDa
Source method src_method	syn
Copy count entity_count	1

Entity 7 Entity 7 non-polymer

Description description	1,2-ETHANEDIOL
Molecular weight formula_weight	62.1 kDa
Source method src_method	syn
Copy count entity_count	2

Entity 8 Entity 8 water

Description description	water
Molecular weight formula_weight	18.0 kDa
Source method src_method	nat
Copy count entity_count	21

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6. Fold Classification (SCOP + CATH) 7 domains

CATH v4.4 (7 domains)

Domain ID domain_id	4mnqA01
Class class	3 — Alpha Beta
Architecture architecture	30 — 2-Layer Sandwich
Topology topology	500 — Murine Class I Major Histocompatibility Complex, H2-DB; Chain A, domain 1
Homologous superfamily homologous superfamily	10 — MHC class I-like antigen recognition-like

Domain ID domain_id	4mnqA02
Class class	2 — Mainly Beta
Architecture architecture	60 — Sandwich
Topology topology	40 — Immunoglobulin-like
Homologous superfamily homologous superfamily	10 — Immunoglobulins

Domain ID domain_id	4mnqB00
Class class	2 — Mainly Beta
Architecture architecture	60 — Sandwich
Topology topology	40 — Immunoglobulin-like
Homologous superfamily homologous superfamily	10 — Immunoglobulins

Domain ID domain_id	4mnqD01
Class class	2 — Mainly Beta
Architecture architecture	60 — Sandwich
Topology topology	40 — Immunoglobulin-like
Homologous superfamily homologous superfamily	10 — Immunoglobulins

Domain ID domain_id	4mnqD02
Class class	2 — Mainly Beta
Architecture architecture	60 — Sandwich
Topology topology	40 — Immunoglobulin-like
Homologous superfamily homologous superfamily	10 — Immunoglobulins

Domain ID domain_id	4mnqE01
Class class	2 — Mainly Beta
Architecture architecture	60 — Sandwich
Topology topology	40 — Immunoglobulin-like
Homologous superfamily homologous superfamily	10 — Immunoglobulins

Domain ID domain_id	4mnqE02
Class class	2 — Mainly Beta
Architecture architecture	60 — Sandwich
Topology topology	40 — Immunoglobulin-like
Homologous superfamily homologous superfamily	10 — Immunoglobulins

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Unit-cell length a length_a	94.220 Å
Unit-cell length b length_b	48.490 Å
Unit-cell length c length_c	118.070 Å
Unit-cell angle α angle_alpha	90.00 °
Unit-cell angle β angle_beta	107.86 °
Unit-cell angle γ angle_gamma	90.00 °
Molecules per unit cell Z z_pdb	2

Space group space_group	P 1 21 1
Space-group number int_tables_number	4
Crystal system crystal_system	—

Resolution resolution	2.742 Å
Low-resolution limit resolution_low	42.150 Å
R factor r_factor	0.2177
R_work r_work	0.2140
R_free r_free	0.2844

TCR-peptide specificity overrides affinity enhancing TCR-MHC interactions

1. Protein Identity and Related Structures Protein Identity & Related Structures

HLA class I histocompatibility antigen, A-2 alpha chain

State in the Current Structure

Other States of the Same Protein in the Database

Monomer

Homodimer

Homotetramer

Other homooligomers

Heteromeric or nucleic-acid complex

Beta-2-microglobulin

State in the Current Structure

Other States of the Same Protein in the Database

Monomer

Homodimer

Homotetramer

Other homooligomers

Heteromeric or nucleic-acid complex

Telomerase reverse transcriptase

State in the Current Structure

Other States of the Same Protein in the Database

Monomer

Homodimer

Homotetramer

Other homooligomers

Heteromeric or nucleic-acid complex

Uncharacterized protein, T-cell receptor, sp3.4 alpha chain

State in the Current Structure

Other States of the Same Protein in the Database

Monomer

Homodimer

Homotetramer

Other homooligomers

Heteromeric or nucleic-acid complex

Uncharacterized protein, T-cell receptor, sp3.4 alpha chain

State in the Current Structure

Other States of the Same Protein in the Database

Monomer

Homodimer

Homotetramer

Other homooligomers

Heteromeric or nucleic-acid complex

V_segment translation product, T-cell receptor beta-1 chain C region

State in the Current Structure

Other States of the Same Protein in the Database

Monomer

Homodimer

Homotetramer

Other homooligomers

Heteromeric or nucleic-acid complex

V_segment translation product, T-cell receptor beta-1 chain C region

State in the Current Structure

Other States of the Same Protein in the Database

Monomer

Homodimer

Homotetramer

Other homooligomers

Heteromeric or nucleic-acid complex

2. Structure Basics 2. Structure Basics

3. Official assembly/model SAXS Official SAXS Profiles

4mnq__assembly_1__model_1

4mnq__assembly_1__model_1 | I(q)

4mnq__assembly_1__model_1 | P(r) · Pending

4. Crystallography and Experiment 4. Crystallography & Experiment

Unit cell Unit Cell

Symmetry Symmetry

Refinement Refinement

Diffraction experiment Diffraction

5. Entities and Polymers Entities & Polymers (8)

Entity 1 Entity 1 polymer

Polymer Polymer

Source Source

Entity 2 Entity 2 polymer

Polymer Polymer

Source Source

Entity 3 Entity 3 polymer

Polymer Polymer

Entity 4 Entity 4 polymer

Polymer Polymer

Source Source