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X-ray crystallographic structure of BshB, the zinc-dependent deacetylase involved in bacillithiol biosynthesis.

ABSTRACT: Many gram-positive bacteria produce bacillithiol to aid in the maintenance of redox homeostasis and degradation of toxic compounds, including the antibiotic fosfomycin. Bacillithiol is produced via a three-enzyme pathway that includes the action of the zinc-dependent deacetylase BshB. Previous studies identified conserved aspartate and histidine residues within the active site that are involved in metal binding and catalysis, but the enzymatic mechanism is not fully understood. Here we report two X-ray crystallographic structures of BshB from Bacillus subtilis that provide insight into the BshB catalytic mechanism.

SUBMITTER: Woodward RL

PROVIDER: S-EPMC7096702 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature

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X-ray crystallographic structure of BshB, the zinc-dependent deacetylase involved in bacillithiol biosynthesis.

Woodward Robert L RL Castleman Michaela M MM Meloche Chelsea E CE Karpen Mary E ME Carlson Clare G CG Yobi William H WH Jepsen Jacqueline C JC Lewis Benjamin W BW Zarnosky Brooke N BN Cook Paul D PD

Protein science : a publication of the Protein Society 20191231 4

Many gram-positive bacteria produce bacillithiol to aid in the maintenance of redox homeostasis and degradation of toxic compounds, including the antibiotic fosfomycin. Bacillithiol is produced via a three-enzyme pathway that includes the action of the zinc-dependent deacetylase BshB. Previous studies identified conserved aspartate and histidine residues within the active site that are involved in metal binding and catalysis, but the enzymatic mechanism is not fully understood. Here we report tw ...[more]

PMID: 31867856

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