3uf9
From Proteopedia
Crystal structure of SsoPox in complex with the phosphotriester fensulfothion
Structural highlights
FunctionPHP_SACS2 Has a low paraoxonase activity. Also active, but with a lower activity, against other organo-phosphorus insecticides such as Dursban, Coumaphos, pNP-butanoate or parathion.[1] Publication Abstract from PubMedSsoPox is a lactonase endowed with promiscuous phosphotriesterase activity isolated from Sulfolobus solfataricus that belongs to the Phosphotriesterase-Like Lactonase family. Because of its intrinsic thermal stability, SsoPox is seen as an appealing candidate as a bioscavenger for organophosphorus compounds. A comprehensive kinetic characterisation of SsoPox has been performed with various phosphotriesters (insecticides) and phosphodiesters (nerve agent analogues) as substrates. We show that SsoPox is active for a broad range of OPs and remains active under denaturing conditions. In addition, its OP hydrolase activity is highly stimulated by anionic detergent at ambient temperature and exhibits catalytic efficiencies as high as k(cat)/K(M) of 10(5) M(-1)s(-1) against a nerve agent analogue. The structure of SsoPox bound to the phosphotriester fensulfothion reveals an unexpected and non-productive binding mode. This feature suggests that SsoPox's active site is sub-optimal for phosphotriester binding, which depends not only upon shape but also on localised charge of the ligand. Characterisation of the organophosphate hydrolase catalytic activity of SsoPox.,Hiblot J, Gotthard G, Chabriere E, Elias M Sci Rep. 2012;2:779. doi: 10.1038/srep00779. Epub 2012 Nov 8. PMID:23139857[2] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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