title: Labeling Studies Clarify the Committed Step in Bacterial Gibberellin Biosynthesis.
abstract: Bacteria have evolved gibberellin phytohormone biosynthesis independently of plants and fungi. Through13C-labeling and NMR analysis, the mechanistically unusual "B" ring contraction catalyzed by a cytochrome P450 (CYP114), which is the committed step in gibberellin biosynthesis, was shown to occur via oxidative extrusion of carbon-7 from ent-kaurenoic acid in bacteria. This is identical to the convergently evolved chemical transformation in plants and fungi, suggesting a common semipinacol rearrangement mechanism potentially guided by carbon-4α carboxylate proximity.
authors.affiliation: Roy J. Carver Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University , Ames, Iowa 50011, United States.
authors.forename: Ryan S
authors.initials: RS
authors.lastname: Nett
authors.affiliation: Kekulé-Institut für Organische Chemie und Biochemie, Rheinische Friedrich-Wilhelms-Universität Bonn , Gerhard-Domagk-Straße 1, 53121 Bonn, Germany.
authors.forename: Jeroen S
authors.initials: JS
authors.lastname: Dickschat
authors.affiliation: Roy J. Carver Department of Biochemistry, Biophysics, and Molecular Biology, Iowa State University , Ames, Iowa 50011, United States.
authors.forename: Reuben J
authors.initials: RJ
authors.lastname: Peters
mesh_terms: D001419:Bacteria / Q000737:chemistry* / Q000378:metabolism; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism*; D005875:Gibberellins / Q000096:biosynthesis* / Q000737:chemistry; D008968:Molecular Conformation
chemical_list: D005875:Gibberellins; D003577:Cytochrome P-450 Enzyme System