H2-Kb binding "SIINFEKL" with antibody at 2.90Å resolution
Data provenance
Information sections
- Publication
- Peptide details
- Peptide neighbours
- Binding cleft pockets
- Chain sequences
- Downloadable data
- Data license
- Footnotes
Complex type
Class i with peptide and antibody
H2-Kb
SIINFEKL
Species
Locus / Allele group
How a T cell receptor-like antibody recognizes major histocompatibility complex-bound peptide.
We determined the crystal structures of the T cell receptor (TCR)-like antibody 25-D1.16 Fab fragment bound to a complex of SIINFEKL peptide from ovalbumin and the H-2K(b) molecule. Remarkably, this antibody directly "reads" the structure of the major histocompatibility complex (MHC)-bound peptide, employing the canonical diagonal binding mode utilized by most TCRs. This is in marked contrast with another TCR-like antibody, Hyb3, bound to melanoma peptide MAGE-A1 in association with HLA-A1 MHC class I. Hyb3 assumes a non-canonical orientation over its cognate peptide-MHC and appears to recognize a conformational epitope in which the MHC contribution is dominant. We conclude that TCR-like antibodies can recognize MHC-bound peptide via two different mechanisms: one is similar to that exploited by the preponderance of TCRs and the other requires a non-canonical antibody orientation over the peptide-MHC complex.
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
SER
TYR171
TYR159
TYR59
LYS66
TYR7
THR163
TRP167
GLU63
LEU5
|
P2
ILE
TYR7
LYS66
ASN70
GLU63
TYR45
GLU24
VAL9
TYR159
|
P3
ILE
TYR159
SER99
LYS66
ASN70
GLN114
LEU156
ARG155
|
P4
ASN
ASN70
ARG155
LYS66
|
P5
PHE
ASN70
GLN114
ARG155
SER99
GLU24
VAL9
PHE74
TYR22
TYR116
SER73
VAL97
|
P6
GLU
ARG155
TYR116
ASP77
ALA150
TRP147
GLU152
|
P7
LYS
TRP147
SER73
ASP77
|
P8
LEU
TRP147
THR143
TYR123
LYS146
TYR116
THR80
TYR84
LEU81
ILE95
ASP77
|
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
THR163
TRP167
TYR171
LEU5
TYR59
GLU63
LYS66
TYR7
|
B Pocket
GLU24
VAL34
TYR45
GLU63
LYS66
ALA67
TYR7
ASN70
VAL9
SER99
|
C Pocket
ASN70
SER73
PHE74
VAL9
VAL97
|
D Pocket
GLN114
ARG155
LEU156
TYR159
LEU160
SER99
|
E Pocket
GLN114
TRP147
GLU152
LEU156
VAL97
|
F Pocket
TYR116
TYR123
THR143
LYS146
TRP147
ASP77
THR80
LEU81
TYR84
ILE95
|
Colour key
Data provenance
1. ab_heavy
ab_heavy
|
10 20 30 40 50 60
VLLQQSGPELVKPGASVKIPCKASGYTFTDYNMDWVKQSHGKSLEWIGDINPNNGGTIYN 70 80 90 100 110 120 QKFKGKATLTVDKSSSAAYMEVRSLTSEDTAVYYCARKPYYGNFAWFAYWGQGTLVTVSA 130 140 150 160 170 180 AKTTPPSVYPLAPGSAAQTNSMVTLGCLVKGYFPEPVTVTWNSGSLSSGVHTFPAVLQSD 190 200 210 LYTLSSSVTVPSSTWPSETVTCNVAHPASSTKVDKKIVP |
2. ab_light
ab_light
|
10 20 30 40 50 60
IQVTQSSSSFSVSLGDRVTITCKASEDIYNRLAWYQQKPGNAPRLLISGATSLETGVPDR 70 80 90 100 110 120 FSGSGSRKDYTLIITSLQTEDVATYYCQQYWSTPLTFGAGTKLELKRADAAPTVSIFPPS 130 140 150 160 170 180 SEQLTSGGASVVCFLNNFYPKDINVKWKIDGSERQNGVLNSWTDQDSKDSTYSMSSTLTL 190 200 TKDEYERHNSYTCEATHKTSTSPIVKSFN |
3. Beta 2 microglobulin
Beta 2 microglobulin
|
10 20 30 40 50 60
IQKTPQIQVYSRHPPENGKPNILNCYVTQFHPPHIEIQMLKNGKKIPKVEMSDMSFSKDW 70 80 90 SFYILAHTEFTPTETDTYACRVKHDSMAEPKTVYWDRDM |
4. Class I alpha
H2-Kb
|
10 20 30 40 50 60
GPHSLRYFVTAVSRPGLGEPRYMEVGYVDDTEFVRFDSDAENPRYEPRARWMEQEGPEYW 70 80 90 100 110 120 ERETQKAKGNEQSFRVDLRTLLGYYNQSKGGSHTIQVISGCEVGSDGRLLRGYQQYAYDG 130 140 150 160 170 180 CDYIALNEDLKTWTAADMAALITKHKWEQAGEAERLRAYLEGTCVEWLRRYLKNGNATLL 190 200 210 220 230 240 RTDSPKAHVTHHSRPEDKVTLRCWALGFYPADITLTWQLNGEELIQDMELVETRPAGDGT 250 260 270 FQKWASVVVPLGKEQYYTCHVYHQGLPEPLTLRW |
5. Peptide
|
SIINFEKL
|
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.