title: Biochemical characterization of NotB as an FAD-dependent oxidase in the biosynthesis of notoamide indole alkaloids.
abstract: Notoamides produced by Aspergillus spp. bearing the bicyclo[2.2.2]diazaoctane core structure with unusual structural diversity represent a compelling system to understand the biosynthesis of fungal prenylated indole alkaloids. Herein, we report the in vitro characterization of NotB, which catalyzes the indole 2,3-oxidation of notoamide E (13), leading to notoamides C (11) and D (12) through an apparent pinacol-like rearrangement. This unique enzymatic reaction with high substrate specificity, together with the information derived from precursor incorporation experiments using [(13)C](2)-[(15)N](2) quadruply labeled notoamide S (10), demonstrates 10 as a pivotal branching point in notoamide biosynthesis.
authors.affiliation: Life Sciences Institute, University of Michigan, Ann Arbor, Michigan 48109, USA.
authors.forename: Shengying
authors.initials: S
authors.lastname: Li
authors.forename: Jennifer M
authors.initials: JM
authors.lastname: Finefield
authors.forename: James D
authors.initials: JD
authors.lastname: Sunderhaus
authors.forename: Timothy J
authors.initials: TJ
authors.lastname: McAfoos
authors.forename: Robert M
authors.initials: RM
authors.lastname: Williams
authors.forename: David H
authors.initials: DH
authors.lastname: Sherman
mesh_terms: D001230:Aspergillus / Q000201:enzymology*; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism*; D015966:Gene Expression Regulation, Fungal / Q000502:physiology*; D026121:Indole Alkaloids / Q000737:chemistry / Q000378:metabolism*; D015394:Molecular Structure; D010088:Oxidoreductases / Q000378:metabolism*
chemical_list: D005656:Fungal Proteins; D026121:Indole Alkaloids; D010088:Oxidoreductases