HLA-B*27:05 binding "ARAAAAAAA" at 2.10Å resolution
Data provenance
Information sections
- Publication
- Peptide details
- Peptide neighbours
- Binding cleft pockets
- Chain sequences
- Downloadable data
- Data license
- Footnotes
Complex type
HLA-B*27:05
ARAAAAAAA
Species
Locus / Allele group
The three-dimensional structure of HLA-B27 at 2.1 A resolution suggests a general mechanism for tight peptide binding to MHC.
Cell surface complexes of class I MHC molecules and bound peptide antigens serve as specific recognition elements controlling the cytotoxic immune response. The 2.1 A structure of the human class I MHC molecule HLA-B27 provides a detailed composite image of a co-crystallized collection of HLA-B27-bound peptides, indicating that they share a common main-chain structure and length. It also permits direct visualization of the conservation of arginine as an "anchor" side chain at the second peptide position, which is bound in a potentially HLA-B27-specific pocket and may therefore have a role in the association of HLA-B27 with several diseases. Tight peptide binding to class I MHC molecules appears to result from the extensive contacts found at the ends of the cleft between peptide main-chain atoms and conserved MHC side chains, which also involve the peptide in stabilizing the three-dimensional fold of HLA-B27. The concentration of binding interactions at the peptide termini permits extensive sequence (and probably some length) variability in the center of the peptide, where it is exposed for T cell recognition.
Structure deposition and release
Data provenance
Publication data retrieved from PDBe REST API8 and PMCe REST API9
Other structures from this publication
Data provenance
MHC:peptide complexes are visualised using PyMol. The peptide is superimposed on a consistent cutaway slice of the MHC binding cleft (displayed as a grey mesh) which best indicates the binding pockets for the P1/P5/PC positions (side view - pockets A, E, F) and for the P2/P3/PC-2 positions (top view - pockets B, C, D). In some cases peptides will use a different pocket for a specific peptide position (atypical anchoring). On some structures the peptide may appear to sterically clash with a pocket. This is an artefact of picking a standardised slice of the cleft and overlaying the peptide.
Peptide neighbours
P1
ALA
TRP167
MET5
GLU163
GLU63
TYR7
TYR59
TYR171
TYR159
ARG62
|
P2
ARG
VAL25
CYS67
VAL34
TYR159
TYR7
ARG62
GLY26
GLU163
GLU63
GLU45
TYR99
THR24
HIS9
ILE66
|
P3
ALA
TYR99
ILE66
TYR159
ARG62
|
P4
ALA
ARG62
ILE66
|
P5
ALA
GLN155
LEU156
|
P6
ALA
THR73
|
P7
ALA
THR73
TRP147
ASP77
VAL152
|
P8
ALA
THR73
TRP147
ASP77
THR143
|
P9
ALA
THR143
TYR84
THR80
TRP147
LEU81
TYR123
ASP77
LYS146
|
Colour key
Data provenance
Neighbours are calculated by finding residues with atoms within 5Å of each other using BioPython Neighboursearch module. The list of neighbours is then sorted and filtered to inlcude only neighbours where between the peptide and the MHC Class I alpha chain.
Colours selected to match the YRB scheme. [https://www.frontiersin.org/articles/10.3389/fmolb.2015.00056/full]
A Pocket
TYR159
GLU163
TRP167
TYR171
MET5
TYR59
GLU63
ILE66
TYR7
|
B Pocket
THR24
VAL34
GLU45
GLU63
ILE66
CYS67
TYR7
LYS70
HIS9
TYR99
|
C Pocket
LYS70
THR73
ASP74
HIS9
ASN97
|
D Pocket
HIS114
GLN155
LEU156
TYR159
LEU160
TYR99
|
E Pocket
HIS114
TRP147
VAL152
LEU156
ASN97
|
F Pocket
ASP116
TYR123
THR143
LYS146
TRP147
ASP77
THR80
LEU81
TYR84
LEU95
|
Colour key
Data provenance
1. Beta 2 microglobulin
Beta 2 microglobulin
|
10 20 30 40 50 60
IQRTPKIQVYSRHPAENGKSNFLNCYVSGFHPSDIEVDLLKNGERIEKVEHSDLSFSKDW 70 80 90 SFYLLYYTEFTPTEKDEYACRVNHVTLSQPKIVKWDRDM |
2. Class I alpha
HLA-B*27:05
IPD-IMGT/HLA
[ipd-imgt:HLA34811] |
10 20 30 40 50 60
GSHSMRYFHTSVSRPGRGEPRFITVGYVDDTLFVRFDSDAASPREEPRAPWIEQEGPEYW 70 80 90 100 110 120 DRETQICKAKAQTDREDLRTLLRYYNQSEAGSHTLQNMYGCDVGPDGRLLRGYHQDAYDG 130 140 150 160 170 180 KDYIALNEDLSSWTAADTAAQITQRKWEAARVAEQLRAYLEGECVEWLRRYLENGKETLQ 190 200 210 220 230 240 RADPPKTHVTHHPISDHEATLRCWALGFYPAEITLTWQRDGEDQTQDTELVETRPAGDRT 250 260 270 FQKWAAVVVPSGEEQRYTCHVQHEGLPKPLTLRWEP |
3. Peptide
|
ARAAAAAAA
|
Data provenance
Sequences are retrieved via the Uniprot method of the RSCB REST API. Sequences are then compared to those derived from the PDB file and matched against sequences retrieved from the IPD-IMGT/HLA database for human sequences, or the IPD-MHC database for other species. Mouse sequences are matched against FASTA files from Uniprot. Sequences for the mature extracellular protein (signal petide and cytoplasmic tail removed) are compared to identical length sequences from the datasources mentioned before using either exact matching or Levenshtein distance based matching.
Downloadable data
Components
Data license
Footnotes
- Protein Data Bank Europe - Coordinate Server
- 1HHK - HLA-A*02:01 binding LLFGYPVYV at 2.5Å resolution - PDB entry for 1HHK
- Protein structure alignment by incremental combinatorial extension (CE) of the optimal path. - PyMol CEALIGN Method - Publication
- PyMol - PyMol.org/pymol
- Levenshtein distance - Wikipedia entry
- Protein Data Bank Europe REST API - Molecules endpoint
- 3Dmol.js: molecular visualization with WebGL - 3DMol.js - Publication
- Protein Data Bank Europe REST API - Publication endpoint
- PubMed Central Europe REST API - Articles endpoint
This work is licensed under a Creative Commons Attribution 4.0 International License.