4cyh
From Proteopedia
Line 1: | Line 1: | ||
[[Image:4cyh.gif|left|200px]] | [[Image:4cyh.gif|left|200px]] | ||
- | + | <!-- | |
- | + | The line below this paragraph, containing "STRUCTURE_4cyh", 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_4cyh| PDB=4cyh | SCENE= }} | |
- | + | ||
- | | | + | |
- | }} | + | |
'''CYCLOPHILIN A COMPLEXED WITH DIPEPTIDE HIS-PRO''' | '''CYCLOPHILIN A COMPLEXED WITH DIPEPTIDE HIS-PRO''' | ||
Line 27: | Line 24: | ||
[[Category: Ke, H.]] | [[Category: Ke, H.]] | ||
[[Category: Zhao, Y.]] | [[Category: Zhao, Y.]] | ||
- | [[Category: | + | [[Category: Binding protein for cyclosporin some]] |
- | [[Category: | + | [[Category: Complex]] |
- | [[Category: | + | [[Category: Cyclophilin]] |
- | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Wed Apr 30 13:58:53 2008'' | |
- | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + |
Revision as of 10:58, 30 April 2008
CYCLOPHILIN A COMPLEXED WITH DIPEPTIDE HIS-PRO
Overview
The structures of cyclophilin A complexed with dipeptides of Ser-Pro, His-Pro, and Gly-Pro have been determined and refined at high resolution. Comparison of these structures revealed that the dipeptide complexes have the same molecular conformation and the same binding of the dipeptides. The side chains of the N-terminal amino acid of the above dipeptides do not strongly interact with cyclophilin, implying their minor contribution to the cis-trans isomerization and thus accounting for the broad catalytic specificity of the enzyme. The binding of the dipeptides is similar to that of the common substrate succinyl-Ala-Ala-Pro-Phe-p-nitroanilide in terms of the N-terminal hydrogen bonding and the hydrophobic interaction of the proline side chain. However, substantial difference between these structures are observed in (1) hydrogen bonding between the carboxyl terminus of the peptides and Arg55 and between Arg55 and Gln63, (2) the side chain conformation of Arg55, and (3) water binding at the active site. These differences imply either that dipeptides are not substrates but competitive inhibitors of peptidyl-prolyl cis-trans isomerases or that dipeptides are subject to different catalytic mechanisms from tetrapeptides.
About this Structure
4CYH is a Single protein structure of sequence from Homo sapiens. Full crystallographic information is available from OCA.
Reference
Mechanistic implication of crystal structures of the cyclophilin-dipeptide complexes., Zhao Y, Ke H, Biochemistry. 1996 Jun 11;35(23):7362-8. PMID:8652512 Page seeded by OCA on Wed Apr 30 13:58:53 2008