1qsw
From Proteopedia
CRYSTAL STRUCTURE ANALYSIS OF A HUMAN LYSOZYME MUTANT W64C C65A
Structural highlights
DiseaseLYSC_HUMAN Defects in LYZ are a cause of amyloidosis type 8 (AMYL8) [MIM:105200; also known as systemic non-neuropathic amyloidosis or Ostertag-type amyloidosis. AMYL8 is a hereditary generalized amyloidosis due to deposition of apolipoprotein A1, fibrinogen and lysozyme amyloids. Viscera are particularly affected. There is no involvement of the nervous system. Clinical features include renal amyloidosis resulting in nephrotic syndrome, arterial hypertension, hepatosplenomegaly, cholestasis, petechial skin rash.[1] FunctionLYSC_HUMAN Lysozymes have primarily a bacteriolytic function; those in tissues and body fluids are associated with the monocyte-macrophage system and enhance the activity of immunoagents. Evolutionary ConservationCheck, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedThe 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. 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[2] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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Categories: Homo sapiens | Large Structures | Inaka K | Kanaya E | Kikuchi M | Miki K