This old version of Proteopedia is provided for student assignments while the new version is undergoing repairs. Content and edits done in this old version of Proteopedia after March 1, 2026 will eventually be lost when it is retired in about June of 2026.
Apply for new accounts at the new Proteopedia. Your logins will work in both the old and new versions.
1a9b
From Proteopedia
| Line 1: | Line 1: | ||
[[Image:1a9b.gif|left|200px]] | [[Image:1a9b.gif|left|200px]] | ||
| - | + | <!-- | |
| - | + | The line below this paragraph, containing "STRUCTURE_1a9b", creates the "Structure Box" on the page. | |
| - | + | You may change the PDB parameter (which sets the PDB file loaded into the applet) | |
| - | | | + | or the SCENE parameter (which sets the initial scene displayed when the page is loaded), |
| - | | | + | or leave the SCENE parameter empty for the default display. |
| - | + | --> | |
| - | + | {{STRUCTURE_1a9b| PDB=1a9b | SCENE= }} | |
| - | + | ||
| - | + | ||
| - | }} | + | |
'''DECAMER-LIKE CONFORMATION OF A NANO-PEPTIDE BOUND TO HLA-B3501 DUE TO NONSTANDARD POSITIONING OF THE C-TERMINUS''' | '''DECAMER-LIKE CONFORMATION OF A NANO-PEPTIDE BOUND TO HLA-B3501 DUE TO NONSTANDARD POSITIONING OF THE C-TERMINUS''' | ||
| Line 29: | Line 26: | ||
[[Category: Saenger, W.]] | [[Category: Saenger, W.]] | ||
[[Category: Ziegler, A.]] | [[Category: Ziegler, A.]] | ||
| - | [[Category: complex | + | [[Category: Histocompatibility complex]] |
| - | [[Category: | + | [[Category: Hla b3501]] |
| - | + | [[Category: Mhc class i]] | |
| - | [[Category: | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Fri May 2 10:00:34 2008'' |
| - | + | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | |
Revision as of 07:00, 2 May 2008
DECAMER-LIKE CONFORMATION OF A NANO-PEPTIDE BOUND TO HLA-B3501 DUE TO NONSTANDARD POSITIONING OF THE C-TERMINUS
Overview
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.
About this Structure
1A9B is a Protein complex structure of sequences from Homo sapiens. Full crystallographic information is available from OCA.
Reference
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 Page seeded by OCA on Fri May 2 10:00:34 2008
