1ko2: Difference between revisions
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==Overview== | ==Overview== | ||
The crystal structures of the universally widespread | 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 Structure== | ==About this Structure== | ||
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[[Category: Single protein]] | [[Category: Single protein]] | ||
[[Category: Dideberg, O.]] | [[Category: Dideberg, O.]] | ||
[[Category: Docquier, J | [[Category: Docquier, J D.]] | ||
[[Category: Garcia-Saez, I.]] | [[Category: Garcia-Saez, I.]] | ||
[[Category: Rossolini, G | [[Category: Rossolini, G M.]] | ||
[[Category: ACT]] | [[Category: ACT]] | ||
[[Category: ZN]] | [[Category: ZN]] | ||
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[[Category: hydrolase]] | [[Category: hydrolase]] | ||
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 13:36:10 2008'' | ||
Revision as of 14:36, 21 February 2008
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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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