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6uy5
From Proteopedia
E. coli cysteine desulfurase SufS with a spontaneously rotated beta-hairpin
Structural highlights
FunctionSUFS_ECOLI Cysteine desulfurases mobilize the sulfur from L-cysteine to yield L-alanine, an essential step in sulfur metabolism for biosynthesis of a variety of sulfur-containing biomolecules. Component of the suf operon, which is activated and required under specific conditions such as oxidative stress and iron limitation. Acts as a potent selenocysteine lyase in vitro, that mobilizes selenium from L-selenocysteine. Selenocysteine lyase activity is however unsure in vivo.[1] [2] [3] [4] [5] Publication Abstract from PubMedCysteine serves as the sulfur source for the biosynthesis of Fe-S clusters and thio-cofactors, molecules that are required for core metabolic processes in all organisms. Therefore, cysteine desulfurases, which mobilize sulfur for its incorporation into thio-cofactors by cleaving the C(alpha)-S bond of cysteine, are ubiquitous in nature. SufS, a type 2 cysteine desulfurase that is present in plants and microorganisms, mobilizes sulfur from cysteine to the transpersulfurase SufE to initiate Fe-S biosynthesis. Here, a 1.5 A resolution X-ray crystal structure of the Escherichia coli SufS homodimer is reported which adopts a state in which the two monomers are rotated relative to their resting state, displacing a beta-hairpin from its typical position blocking transpersulfurase access to the SufS active site. A global structure and sequence analysis of SufS family members indicates that the active-site beta-hairpin is likely to require adjacent structural elements to function as a beta-latch regulating access to the SufS active site. Structural evidence for a latch mechanism regulating access to the active site of SufS-family cysteine desulfurases.,Dunkle JA, Bruno MR, Frantom PA Acta Crystallogr D Struct Biol. 2020 Mar 1;76(Pt 3):291-301. doi: , 10.1107/S2059798320000790. Epub 2020 Feb 25. PMID:32133993[6] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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