1qsw
From Proteopedia
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CRYSTAL STRUCTURE ANALYSIS OF A HUMAN LYSOZYME MUTANT W64C C65A
Contents |
Overview
The three-dimensional structure of a mutant human lysozyme, W64CC65A, in, which a non-native disulfide bond Cys64--Cys81 is substituted for the, Cys65--Cys81 of the wild type protein by replacing Trp64 and Cys65 with, Cys and Ala, respectively, was determined by X-ray crystallography and, refined to an R-value of 0.181, using 33,187 reflections at 1.87-A, resolution. The refined model of the W64CC65A protein consisted of four, molecules, which were related by two noncrystallographic twofold axes and, a translation vector. Although no specific structural differences could be, observed among these four molecules, the overall B-factors of each, molecule were quite different. The overall structure of W64CC65A, especially in the alpha-helical domain, was found to be quite similar to, that of the wild type protein. Moreover, the side-chain conformation of, the newly formed Cys64--Cys81 bond was quite similar to that of the, Cys65--Cys81 bond of the wild-type protein. However, in the beta-sheet, domain, the main-chain atoms of the loop region from positions 66-75 could, not be determined, and significant structural changes due to the formation, of the non-native disulfide bond could be observed. From these results, it, is clear that the loop region of the mutant protein does not fold with the, specific folding as observed in the wild-type protein.
Disease
Known diseases associated with this structure: Amyloidosis, renal OMIM:[153450], Microphthalmia, syndromic 1 OMIM:[309800]
About this Structure
1QSW is a Single protein structure of sequence from Homo sapiens. Full crystallographic information is available from OCA.
Reference
Crystal structure of a mutant human lysozyme with a substituted disulfide bond., Inaka K, Kanaya E, Kikuchi M, Miki K, Proteins. 2001 Jun 1;43(4):413-9. PMID:11340658
Page seeded by OCA on Mon Nov 12 18:56:24 2007
