BIOSYNTHESIS OF CONJUGATED OLEFINIC SYSTEMS IN THE SEX-PHEROMONE GLAND OF FEMALE TOBACCO HORNWORM MOTHS, MANDUCA-SEXTA (L)

Citation
Nb. Fang et al., BIOSYNTHESIS OF CONJUGATED OLEFINIC SYSTEMS IN THE SEX-PHEROMONE GLAND OF FEMALE TOBACCO HORNWORM MOTHS, MANDUCA-SEXTA (L), Insect biochemistry and molecular biology, 25(1), 1995, pp. 39-48
Citations number
24
Categorie Soggetti
Entomology,Biology
ISSN journal
09651748
Volume
25
Issue
1
Year of publication
1995
Pages
39 - 48
Database
ISI
SICI code
0965-1748(1995)25:1<39:BOCOSI>2.0.ZU;2-K
Abstract
Deuterium-labelled fatty acid putative precursors of the 16-carbon ald ehydic sex pheromones of Manduca sexta (L.) were applied to the sex ph eromone glands of females. After 24 h in vivo incubation, and injectio n of pheromone biosynthesis activating neuropeptide into the abdomens of treated females, glands were excised, extracted, and the extracts a nalyzed by gas chromatography-mass spectrometry. Incubation of glands with [16, 16, 16-H-2(3)] hexadecanoic acid resulted in the label being incorporated into seven of the eight 16-carbon aldehydes found in the gland, including monoenes, dienes, and trienes. Similarly, incubation with [16, 16, 16-H-2(3)] (Z)-11-hexadecenoic acid led to incorporatio n of the label into (Z)-11-hexadecenal and both conjugated diene and t riene aldehydes. However, incubation with [13, 13, 14, 14, 15, 15, 16, 16, 16-H-2(9)] (Z)-11-hexadecenoic acid resulted in incorporation of the label into only (Z)-11-hexadecenal, (E, Z)- and (E, E)-10, 12-hexa decadienal, indicating interference of the deuterium isotope in the de saturation process leading to the conjugated triene system, Incubation with the similarly labelled (E)-11-hexadecenoic acids gave labelled ( E)-11-hexadecenal in both cases, but none of the other unsaturated phe romone aldehydes. The results indicate that fatty acids are the precur sors of the aldehydic pheromones in this species and that hexadecanoat e is the precursor of the 16-carbon monoenes, dienes, and trienes. The conjugated dienes and trienes are formed via desaturation/isomerizati on of (Z)-11-hexadecenoate.