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Active-site structure of a ?-hydroxylase in antibiotic biosynthesis.

ABSTRACT: X-ray absorption and resonance Raman spectroscopies show that CmlA, the ?-hydroxylase of the chloramphenicol biosynthetic pathway, contains a (?-oxo)-(?-1,3-carboxylato)diiron(III) cluster with 6-coordinate iron centers and 3 - 4 His ligands. This active site is found within a unique ?-lactamase fold and is distinct from those of soluble methane monooxygenase and related enzymes that utilize a highly conserved diiron cluster with a 2-His-4-carboxylate ligand set within a 4-helix bundle motif. These structural differences may have an impact on the nature of the activated oxygen species of the reaction cycle.

SUBMITTER: Vu VV

PROVIDER: S-EPMC3096070 | biostudies-literature | 2011 May

REPOSITORIES: biostudies-literature

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Active-site structure of a β-hydroxylase in antibiotic biosynthesis.

Vu Van V VV Makris Thomas M TM Lipscomb John D JD Que Lawrence L

Journal of the American Chemical Society 20110420 18

X-ray absorption and resonance Raman spectroscopies show that CmlA, the β-hydroxylase of the chloramphenicol biosynthetic pathway, contains a (μ-oxo)-(μ-1,3-carboxylato)diiron(III) cluster with 6-coordinate iron centers and 3 - 4 His ligands. This active site is found within a unique β-lactamase fold and is distinct from those of soluble methane monooxygenase and related enzymes that utilize a highly conserved diiron cluster with a 2-His-4-carboxylate ligand set within a 4-helix bundle motif. Th ...[more]

PMID: 21506543

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