title: Active-site structure of a β-hydroxylase in antibiotic biosynthesis.
abstract: 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. These structural differences may have an impact on the nature of the activated oxygen species of the reaction cycle.
authors.affiliation: Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, USA.
authors.forename: Van V
authors.initials: VV
authors.lastname: Vu
authors.forename: Thomas M
authors.initials: TM
authors.lastname: Makris
authors.forename: John D
authors.initials: JD
authors.lastname: Lipscomb
authors.forename: Lawrence
authors.initials: L
authors.lastname: Que
mesh_terms: D015502:Absorptiometry, Photon; D020816:Amino Acid Motifs; D000900:Anti-Bacterial Agents / Q000096:biosynthesis*; D020134:Catalytic Domain; D002701:Chloramphenicol / Q000096:biosynthesis*; D006899:Mixed Function Oxygenases / Q000737:chemistry*; D011487:Protein Conformation; D013059:Spectrum Analysis, Raman
chemical_list: D000900:Anti-Bacterial Agents; D002701:Chloramphenicol; D006899:Mixed Function Oxygenases