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1HSA

HLA-B*27:05 binding "ARAAAAAAA" at 2.10Å resolution

Data provenance

Structure downloaded from PDB Europe using the Coordinate Server. Aligned to residues 1-180 of 1HHK2 using the CEALIGN3 function of PyMol4. Chain assigment using a Levenshtein distance5 method using data from the PDBe REST API6. Organism data from PDBe REST API. Data for both of these operations from the Molecules endpoint. Structure visualised with 3DMol7.

Information sections


Complex type

Class i with peptide

1. Beta 2 microglobulin
['B', 'E']
2. Class I alpha
HLA-B*27:05
['A', 'D']
3. Peptide
ARAAAAAAA
['C', 'F']

Species


Locus / Allele group


Publication

The three-dimensional structure of HLA-B27 at 2.1 A resolution suggests a general mechanism for tight peptide binding to MHC.

Madden DR, Gorga JC, Strominger JL, Wiley DC
Cell (1992) 70, 1035-48 [doi:10.1016/0092-8674(92)90252-8]  [pubmed:1525820

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

Deposited: 1992-08-11
Released: 1992-10-15
Revised: 2011-07-13

Data provenance

Publication data retrieved from PDBe REST API8 and PMCe REST API9

Other structures from this publication


Peptide details

Length: Nonamer (9 amino acids)

Sequence: ARAAAAAAA

Interactive view
Cutaway side view (static)
Surface top view (static - coloured by atom property)
Cutaway top view (static)

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

Aromatic Hydrophobic Acidic Basic Neutral/polar

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]


Binding cleft pockets


Peptide sidechain binding pockets (static)
Peptide terminii and backbone binding residues (static)
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

Binds N-terminus Binds P1 backbone Binds P2 backbone Binds PC-1 backbone Binds C-terminus

Data provenance

N-/C-terminus and peptide backbone binding residues are assigned according to previously published information and pockets are assigned according to an adaptation of a previously published set of residues. All numbering is currently that of the 'canonical' structures of human and mouse MHC Class I molecules.

Chain sequences

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

Data can be downloaded to your local machine from the links below.
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or in the case of JSON formatted files to retrieve it and use it as part of notebooks such as Jupyter or GoogleColab.
Please take note of the data license. Using data from this site assumes that you have read and will comply with the license.

Complete structures

Aligned structures [cif]
  1. 1HSA assembly 1  
  2. 1HSA assembly 2  

Components

MHC Class I alpha chain [cif]
  1. 1HSA assembly 1  
  2. 1HSA assembly 2  
MHC Class I antigen binding domain (alpha1/alpha2) [cif]
  1. 1HSA assembly 1  
  2. 1HSA assembly 2  
Peptide only [cif]
  1. 1HSA assembly 1  
  2. 1HSA assembly 2  

Derived data

Data for this page [json]
https://api.histo.fyi/v1/structures/1hsa

Data license

The data above is made available under a Creative Commons CC-BY 4.0 license. This means you can copy, remix, transform, build upon and redistribute the material, but you must give appropriate credit, provide a link to the license, and indicate if changes were made.
If you use any data downloaded from this site in a publication, please cite 'https://www.histo.fyi/'. A preprint is in preparation.

Footnotes