title: An altered position of the alpha 2 helix of MHC class I is revealed by the crystal structure of HLA-B*3501.
abstract: The crystal structure of the human major histocompatibility complex class I B allele HLA B*3501 complexed with the 8-mer peptide epitope HIV1 Nef 75-82 (VPLRPMTY) has been determined at 2.0 angstrom resolution. Comparison with the crystal structure of the closely related allele HLA B*5301 reveals the structural basis for the tyrosine specificity of the B*3501 F pocket. The structure also reveals a novel conformation of the 8-mer peptide within the binding groove. The positions of the peptide N and C termini are nonstandard, but the classic pattern of hydrogen bonding to nonpolymorphic MHC class I residues is maintained, at the N terminus by addition of a water molecule, and at the C terminus by a substantial shift in the alpha 2 helix.
authors.affiliation: Nuffield Department of Clinical Medicine, Institute of Molecular Medicine, John Radcliffe Hospital, Oxford, United Kingdom.
authors.forename: K J
authors.initials: KJ
authors.lastname: Smith
authors.forename: S W
authors.initials: SW
authors.lastname: Reid
authors.forename: D I
authors.initials: DI
authors.lastname: Stuart
authors.forename: A J
authors.initials: AJ
authors.lastname: McMichael
authors.forename: E Y
authors.initials: EY
authors.lastname: Jones
authors.forename: J I
authors.initials: JI
authors.lastname: Bell
mesh_terms: D000483:Alleles; D000595:Amino Acid Sequence; D001483:Base Sequence; D018360:Crystallography, X-Ray; D015693:Gene Products, nef / Q000737:chemistry; D015797:HLA-B35 Antigen / Q000737:chemistry*; D006801:Humans; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011485:Protein Binding; D011487:Protein Conformation
chemical_list: D015693:Gene Products, nef; D015797:HLA-B35 Antigen