title: Generation of complexity in fungal terpene biosynthesis: discovery of a multifunctional cytochrome P450 in the fumagillin pathway.
abstract: Fumagillin (1), a meroterpenoid from Aspergillus fumigatus, is known for its antiangiogenic activity due to binding to human methionine aminopeptidase 2. 1 has a highly oxygenated structure containing a penta-substituted cyclohexane that is generated by oxidative cleavage of the bicyclic sesquiterpene β-trans-bergamotene. The chemical nature, order, and biochemical mechanism of all the oxygenative tailoring reactions has remained enigmatic despite the identification of the biosynthetic gene cluster and the use of targeted-gene deletion experiments. Here, we report the identification and characterization of three oxygenases from the fumagillin biosynthetic pathway, including a multifunctional cytochrome P450 monooxygenase, a hydroxylating nonheme-iron-dependent dioxygenase, and an ABM family monooxygenase for oxidative cleavage of the polyketide moiety. Most significantly, the P450 monooxygenase is shown to catalyze successive hydroxylation, bicyclic ring-opening, and two epoxidations that generate the sesquiterpenoid core skeleton of 1. We also characterized a truncated polyketide synthase with a ketoreductase function that controls the configuration at C-5 of hydroxylated intermediates.
authors.affiliation: Department of Chemical and Biomolecular Engineering, and #Department of Chemistry and Biochemistry, University of California , Los Angeles, California 90095.
authors.forename: Hsiao-Ching
authors.initials: HC
authors.lastname: Lin
authors.forename: Yuta
authors.initials: Y
authors.lastname: Tsunematsu
authors.forename: Sourabh
authors.initials: S
authors.lastname: Dhingra
authors.forename: Wei
authors.initials: W
authors.lastname: Xu
authors.forename: Manami
authors.initials: M
authors.lastname: Fukutomi
authors.forename: Yit-Heng
authors.initials: YH
authors.lastname: Chooi
authors.forename: David E
authors.initials: DE
authors.lastname: Cane
authors.forename: Ana M
authors.initials: AM
authors.lastname: Calvo
authors.forename: Kenji
authors.initials: K
authors.lastname: Watanabe
authors.forename: Yi
authors.initials: Y
authors.lastname: Tang
mesh_terms: D001232:Aspergillus fumigatus / Q000737:chemistry* / Q000378:metabolism; D003510:Cyclohexanes / Q000737:chemistry / Q000378:metabolism*; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism*; D005231:Fatty Acids, Unsaturated / Q000737:chemistry / Q000378:metabolism*; D015394:Molecular Structure; D012717:Sesquiterpenes / Q000737:chemistry / Q000378:metabolism; D013729:Terpenes / Q000737:chemistry / Q000378:metabolism*
chemical_list: D003510:Cyclohexanes; D005231:Fatty Acids, Unsaturated; D012717:Sesquiterpenes; D013729:Terpenes; C026211:fumagillin; D003577:Cytochrome P-450 Enzyme System