1a9e

DECAMER-LIKE CONFORMATION OF A NANO-PEPTIDE BOUND TO HLA-B3501 DUE TO NONSTANDARD POSITIONING OF THE C-TERMINUS

spinqualitylabelsall models 1a9e, resolution 2.50Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image   Print3D Structural highlights 1a9e is a 3 chain structure with sequence from Homo sapiens and Human gammaherpesvirus 4. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Method: X-ray diffraction, Resolution 2.5Å Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Disease B2MG_HUMAN Defects in B2M are the cause of hypercatabolic hypoproteinemia (HYCATHYP) [MIM:241600. Affected individuals show marked reduction in serum concentrations of immunoglobulin and albumin, probably due to rapid degradation. Note=Beta-2-microglobulin may adopt the fibrillar configuration of amyloid in certain pathologic states. The capacity to assemble into amyloid fibrils is concentration dependent. Persistently high beta(2)-microglobulin serum levels lead to amyloidosis in patients on long-term hemodialysis. Function B2MG_HUMAN Component of the class I major histocompatibility complex (MHC). Involved in the presentation of peptide antigens to the immune system. Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMed The N and C termini of peptides presented by major histocompatibility complex (MHC) class I molecules are held within the peptide binding groove by a network of hydrogen bonds to conserved MHC residues. However, the published structure of the human allele HLA-B*3501 complexed with the nef octa-peptide VPLRPMTY, revealed non-standard positioning for both peptide termini. To investigate whether these deviations are indeed related to the length of the nef-peptide, we have determined the structure of HLA-B*3501 presenting a nona-peptide to 2.5 A resolution. A comparison of HLA-B*3501/peptide complexes with structures of other HLA molecules exhibits allele-specific properties of HLA-B*3501, as well as peptide-induced structural changes. Independent of the length of the bound peptide, HLA-B*3501 positions the peptide C terminus significantly closer to the alpha1-helix and nearer to the A pocket than observed for other HLA class I/peptide complexes. This reorientation is accompanied by a shift within the N-terminal part of the alpha2-helix towards the middle of the binding groove. Due to the short distance between the N and C termini, the nona-peptide is compressed and forced to zig-zag vertically within the binding groove. Its conformation rather resembles that of a deca-peptide than of other nona-peptides bound to class I molecules. Superposition of both HLA-B*3501/peptide complexes additionally reveals a significant, peptide-dependent deviation between the N-terminal parts of the alpha1-helices which might be due to different positioning of the peptide N termini. Taken together, these data illustrate the strong interdependence between the HLA class I molecule and the bound peptide. Decamer-like conformation of a nona-peptide bound to HLA-B*3501 due to non-standard positioning of the C terminus.,Menssen R, Orth P, Ziegler A, Saenger W J Mol Biol. 1999 Jan 15;285(2):645-53. PMID:9878435 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See Also Beta-2 microglobulin 3D structures MHC 3D structures MHC I 3D structures

Proteopedia Page Contributors and Editors (what is this?)

OCA