| Title: | Unusual mechanism of hydrocarbon formation in the housefly: cytochrome P450 converts aldehyde to the sex pheromone component (Z)-9-tricosene and CO2 |
| Author(s): | Reed JR; Vanderwel D; Choi S; Pomonis JG; Reitz RC; Blomquist GJ; |
| Address: | "Department of Biochemistry, University of Nevada, Reno 89557-0014" |
| ISSN/ISBN: | 0027-8424 (Print) 1091-6490 (Electronic) 0027-8424 (Linking) |
| Abstract: | "An unusual mechanism for hydrocarbon biosynthesis is proposed from work examining the formation of (Z)-9-tricosene (Z9-23:Hy), the major sex pheromone component of the female housefly, Musca domestica. Incubation of (Z)-15-[1-14C]- and (Z)-15-[15,16-3H2]tetracosenoic acid (24:1 fatty acid) with microsomes from houseflies gave equal amounts of [3H]Z9-23:Hy and 14CO2. The formation of CO2 and not CO, as reported for hydrocarbon formation in plants, animals, and microorganisms [Dennis, M. & Kolattukudy, P. E. (1992) Proc. Natl. Acad. Sci. USA 89, 5306-5310], was verified by trapping agents and by radio-GLC analysis. Incubation of (Z)-15-[15,16-3H2]tetracosenoyl-CoA with microsomal preparations in the presence of NADPH and O2 gave almost equal amounts of (Z)-15-3H2]tetrasosenal (24:1 aldehyde) and Z9-23:Hy. Addition of increasing amounts of hydroxylamine (aldehyde trapping agent) caused a decrease in hydrocarbon formation with a concomitant increase in oxime (aldehyde derivative) formation. The 24:1 aldehyde was efficiently converted to (Z)-9-tricosene only in the presence of both NADPH and O2. Bubbling carbon monoxide (20:80 CO/O2) or including an antibody against housefly cytochrome P450 reductase inhibited the formation Z9-23:Hy from 24:1 aldehyde. These data demonstrate an unusual mechanism for hydrocarbon formation in insects in which the acyl-CoA is reduced to the corresponding aldehyde and then carbon-1 is removed as CO2. The requirement for NADPH and O2 and the inhibition by CO and the antibody to cytochrome P450 reductase strongly implicate the participation of a cytochrome P450 in this reaction" |
| Keywords: | "Aldehydes/metabolism Alkenes/*metabolism Animals Carbon Dioxide/metabolism Carbon Radioisotopes Cytochrome P-450 Enzyme System/*metabolism Fatty Acids, Monounsaturated/*metabolism Female Houseflies/*enzymology Hydrocarbons/metabolism Kinetics Microsomes/*;Animals;" |
| Notes: | "MedlineReed, J R Vanderwel, D Choi, S Pomonis, J G Reitz, R C Blomquist, G J eng Research Support, U.S. Gov't, Non-P.H.S. 1994/10/11 Proc Natl Acad Sci U S A. 1994 Oct 11; 91(21):10000-4. doi: 10.1073/pnas.91.21.10000" |
