2HLA

SPECIFICITY POCKETS FOR THE SIDE CHAINS OF PEPTIDE ANTIGENS IN HLA-AW68

Summary for 2HLA

• Entry DOI: 10.2210/pdb2hla/pdb
• Descriptor: CLASS I HISTOCOMPATIBILITY ANTIGEN (HLA-Aw68), BETA 2-MICROGLOBULIN (3 entities in total)
• Functional Keywords: histocompatibility antigen
• Biological source: Homo sapiens (human); More
• Cellular location: Membrane; Single-pass type I membrane protein: P01891; Secreted . Note=(Microbial infection) In the presence of M: P61769
• Total number of polymer chains: 2
• Total formula weight: 42899.49

Authors

Garrett, T.P.J.,Saper, M.A.,Wiley, D.C. (deposition date: 1989-10-05, release date: 1990-04-15, Last modification date: 2024-10-23)

Primary citation

Garrett, T.P.,Saper, M.A.,Bjorkman, P.J.,Strominger, J.L.,Wiley, D.C.
Specificity pockets for the side chains of peptide antigens in HLA-Aw68.
Nature, 342:692-696, 1989

PubMed Abstract: We have determined the structure of a second human histocompatibility glycoprotein, HLA-Aw68, by X-ray crystallography and refined it to a resolution of 2.6 A. Overall, the structure is extremely similar to that of HLA-A2 (refs 1, 2; and M.A.S. et al., manuscript in preparation), although the 11 amino-acid substitutions at polymorphic residues in the antigen-binding cleft alter the detailed shape and electrostatic charge of that site. A prominent negatively charged pocket within the cleft extends underneath the alpha-helix of the alpha 1-domain, providing a potential subsite for recognizing a positively charged side chain or peptide N terminus. Uninterpreted electron density, presumably representing an unknown 'antigen(s)', which seems to be different from that seen in the HLA-A2 structure, occupies the cleft and extends into the negatively charged pocket in HLA-Aw68. The structures of HLA-Aw68 and HLA-A2 demonstrate how polymorphism creates and alters subsites (pockets) positioned to bind peptide side chains, thereby suggesting the structural basis for allelic specificity in foreign antigen binding.

PubMed: 2594067
DOI: 10.1038/342692a0

Experimental method

X-RAY DIFFRACTION (2.6 Å)