2qcp
From Proteopedia
1.0 A Structure of CusF-Ag(I) residues 10-88 from Escherichia coli
Structural highlights
FunctionCUSF_ECOLI Part of a cation efflux system that mediates resistance to copper and silver. Binds one copper per polypeptide.[1] Evolutionary ConservationCheck, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedElevated levels of copper or silver ions in the environment are an immediate threat to many organisms. Escherichia coli is able to resist the toxic effects of these ions through strictly limiting intracellular levels of Cu(I) and Ag(I). The CusCFBA system is one system in E. coli responsible for copper/silver tolerance. A key component of this system is the periplasmic copper/silver-binding protein, CusF. Here the X-ray structure and XAS data on the CusF-Ag(I) and CusF-Cu(I) complexes, respectively, are reported. In the CusF-Ag(I) structure, Ag(I) is coordinated by two methionines and a histidine, with a nearby tryptophan capping the metal site. EXAFS measurements on the CusF-Cu(I) complex show a similar environment for Cu(I). The arrangement of ligands effectively sequesters the metal from its periplasmic environment and thus may play a role in protecting the cell from the toxic ion. Unusual Cu(I)/Ag(I) coordination of Escherichia coli CusF as revealed by atomic resolution crystallography and X-ray absorption spectroscopy.,Loftin IR, Franke S, Blackburn NJ, McEvoy MM Protein Sci. 2007 Oct;16(10):2287-93. PMID:17893365[2] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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