1ko2
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VIM-2, a Zn-beta-lactamase from Pseudomonas aeruginosa with an oxidized Cys (cysteinesulfonic)
OverviewOverview
The crystal structures of the universally widespread, metallo-beta-lactamase (MBL) Verona integron-encoded MBL (VIM)-2 from, Pseudomonas aeruginosa have been solved in their native form as well as in, an unexpected oxidised form. This carbapenem-hydrolysing enzyme belongs to, the so-called B1 subfamily of MBLs and shares the folding of alpha, beta/beta alpha sandwich, consisting of a core of beta-sheet surrounded by, alpha-helices. Surprisingly, it showed a high tendency to be strongly, oxidised at the catalytic cysteine located in the Cys site, Cys221, which, in the oxidised structure, becomes a cysteinesulfonic residue. Its native, structure was obtained only in the presence of, Tris(2-carboxyethyl)phosphine. This oxidation might be a consequence of a, lower affinity for the second Zn located in the Cys site that would also, explain the observed susceptibility of VIM-2 to chelating agents. This, modification, if present in nature, might play a role in catalytic, down-regulation. Comparison between native and oxidised VIM-2 and a, predicted model of VIM-1 (which shows one residue different in the Cys, site compared with VIM-2) is performed to explain the different activities, and antibiotic specificities.
About this StructureAbout this Structure
1KO2 is a Single protein structure of sequence from Pseudomonas aeruginosa with and as ligands. Active as Hydrolase, with EC number 3.5.2.6 Full crystallographic information is available from OCA.
ReferenceReference
The three-dimensional structure of VIM-2, a Zn-beta-lactamase from Pseudomonas aeruginosa in its reduced and oxidised form., Garcia-Saez I, Docquier JD, Rossolini GM, Dideberg O, J Mol Biol. 2008 Jan 18;375(3):604-11. Epub 2007 Nov 13. PMID:18061205
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