PMID: 8624812 , Related PDB id: UNKNOWN
Smith KJ, Reid SW, Harlos K, McMichael AJ, Stuart DI, Bell JI, Jones EY
Bound water structure and polymorphic amino acids act together to allow the binding of different peptides to MHC class I HLA-B53.
Immunity. 1996 Mar;4(3):215-28.
The structure of the human MHC class I molecule HLA-B53 complexed to two nonameric peptide epitopes (from the malaria parasite P. falciparum and the HIV2 gag protein) has been determined by X-ray crystallography at 2.3 angstrom resolution. The structures reveal the architecture of a Pro-specific B pocket common to many HLA-B alleles. Relative to other alleles, the B53 peptide-binding groove is widened by a significant (up to 1.25 angstrom) shift in the position of the alpha 1 helix. Within this groove, bound water molecules, acting in concert with the side chains of polymorphic residues, provide the functional malleability of the MHC, which enables the high affinity/low specificity binding of multiple peptide epitopes.