title: CYP345E2, an antenna-specific cytochrome P450 from the mountain pine beetle, Dendroctonus ponderosae Hopkins, catalyses the oxidation of pine host monoterpene volatiles.
abstract: The mountain pine beetle (MPB, Dendroctonus ponderosae Hopkins) is a significant pest of western North American pine forests. This beetle responds to pheromones and host volatiles in order to mass attack and thus overcome the terpenoid chemical defences of its host. The ability of MPB antennae to rapidly process odorants is necessary to avoid odorant receptor saturation and thus the enzymes responsible for odorant clearance are an important aspect of host colonization. An antenna-specific cytochrome P450, DponCYP345E2, is the most highly expressed transcript in adult MPB antenna. In in vitro assays with recombinant enzyme, DponCYP345E2 used several pine host monoterpenes as substrates, including (+)-(3)-carene, (+)-β-pinene, (-)-β-pinene, (+)-limonene, (-)-limonene, (-)-camphene, (+)-α-pinene, (-)-α-pinene, and terpinolene. The substrates were epoxidized or hydroxylated, depending upon the substrate. To complement DponCYP345E2, we also functionally characterized the NADPH-dependent cytochrome P450 reductase and the cytochrome b5 from MPB. DponCYP345E2 is the first cytochrome P450 to be functionally characterized in insect olfaction and in MPB.
authors.affiliation: Michael Smith Laboratories, University of British Columbia, 301-2185 East Mall, Vancouver, BC, Canada V6T 1A4. Electronic address: ckeeling@alumni.sfu.ca.
authors.forename: Christopher I
authors.initials: CI
authors.lastname: Keeling
authors.forename: Hannah
authors.initials: H
authors.lastname: Henderson
authors.forename: Maria
authors.initials: M
authors.lastname: Li
authors.forename: Harpreet K
authors.initials: HK
authors.lastname: Dullat
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Ohnishi
authors.forename: Jörg
authors.initials: J
authors.lastname: Bohlmann
mesh_terms: D000818:Animals; D000081008:Bicyclic Monoterpenes; D001643:Bridged Bicyclo Compounds / Q000378:metabolism; D002384:Catalysis; D001517:Coleoptera / Q000378:metabolism; D053138:Cyclohexenes / Q000378:metabolism; D003577:Cytochrome P-450 Enzyme System / Q000737:chemistry / Q000378:metabolism*; D006790:Host-Parasite Interactions / Q000235:genetics*; D000077222:Limonene; D039821:Monoterpenes / Q000378:metabolism; D010084:Oxidation-Reduction; D028223:Pinus / Q000378:metabolism*; D013729:Terpenes / Q000378:metabolism*
chemical_list: D000081008:Bicyclic Monoterpenes; D001643:Bridged Bicyclo Compounds; D053138:Cyclohexenes; D039821:Monoterpenes; D013729:Terpenes; C010789:beta-pinene; D003577:Cytochrome P-450 Enzyme System; D000077222:Limonene; C019286:camphene; C005451:alpha-pinene
keywords: CPR; Cytochrome P450; Cytochrome b(5); GST; MPB; NADPH-dependent cytochrome P450 reductase; ODE; Odorant clearance; Olfaction; P450; Terpene; cytochrome P450; glutathione S-transferase; mountain pine beetle; odorant-degrading enzyme