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Mechanism for the hydrolysis of a sulfur-sulfur bond based on the crystal structure of the thiosulfohydrolase SoxB.

ABSTRACT: SoxB is an essential component of the bacterial Sox sulfur oxidation pathway. SoxB contains a di-manganese(II) site and is proposed to catalyze the release of sulfate from a protein-bound cysteine S-thiosulfonate. A direct assay for SoxB activity is described. The structure of recombinant Thermus thermophilus SoxB was determined by x-ray crystallography to a resolution of 1.5 A. Structures were also determined for SoxB in complex with the substrate analogue thiosulfate and in complex with the product sulfate. A mechanistic model for SoxB is proposed based on these structures.

SUBMITTER: Sauve V

PROVIDER: S-EPMC2755893 | biostudies-literature | 2009 Aug

REPOSITORIES: biostudies-literature

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Mechanism for the hydrolysis of a sulfur-sulfur bond based on the crystal structure of the thiosulfohydrolase SoxB.

Sauvé Véronique V Roversi Pietro P Leath Kirstin J KJ Garman Elspeth F EF Antrobus Robin R Lea Susan M SM Berks Ben C BC

The Journal of biological chemistry 20090616 32

SoxB is an essential component of the bacterial Sox sulfur oxidation pathway. SoxB contains a di-manganese(II) site and is proposed to catalyze the release of sulfate from a protein-bound cysteine S-thiosulfonate. A direct assay for SoxB activity is described. The structure of recombinant Thermus thermophilus SoxB was determined by x-ray crystallography to a resolution of 1.5 A. Structures were also determined for SoxB in complex with the substrate analogue thiosulfate and in complex with the pr ...[more]

PMID: 19535341

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