title: First biosynthetic pathway of 1-hepten-3-one in Iporangaia pustulosa (Opiliones).
abstract: Arthropods produce a great variety of natural compounds, many of which have unexplored biosynthesis. Among the armored harvestmen (Arachnida: Opiliones) of the suborder Laniatores, the defensive gland exudates contain vinyl ketones and other constituents of supposed polyketide origin. We have studied the biosynthesis of 1-hepten-3-one in the Neotropical harvestman Iporangaia pustulosa by feeding individuals with ¹³C-labeled precursors, demonstrating its mixed acetate/propionate origin. ¹³C NMR spectroscopy showed an unusual labeling pattern suggesting different propionate sources for starting and extender units. Our analysis also indicates the presence of methylmalonyl-CoA mutase, converting acetate into propionyl-CoA via succinyl-CoA, together with other C₃ unit routes. This is the first biosynthetic study of alkyl vinyl ketones in arthropods. Our results shed light on the origin and diversification of chemical compounds in a major arthropod group.
authors.affiliation: Chemistry Institute, State University of Campinas, POB 6154, 13083-970 Campinas, SP, Brazil.
authors.forename: Daniele F O
authors.initials: DF
authors.lastname: Rocha
authors.forename: Felipe C
authors.initials: FC
authors.lastname: Wouters
authors.forename: Glauco
authors.initials: G
authors.lastname: Machado
authors.forename: Anita J
authors.initials: AJ
authors.lastname: Marsaioli
mesh_terms: D000214:Acyl Coenzyme A / Q000378:metabolism; D000475:Alkenes / Q000378:metabolism*; D000818:Animals; D001097:Arachnida / Q000201:enzymology / Q000378:metabolism*; D002247:Carbon Isotopes / Q000737:chemistry; D007659:Ketones / Q000737:chemistry / Q000378:metabolism*; D009682:Magnetic Resonance Spectroscopy; D008765:Methylmalonyl-CoA Mutase / Q000378:metabolism; D011422:Propionates / Q000737:chemistry / Q000378:metabolism
chemical_list: D000214:Acyl Coenzyme A; D000475:Alkenes; D002247:Carbon Isotopes; D007659:Ketones; D011422:Propionates; C009061:propionyl-coenzyme A; C012046:succinyl-coenzyme A; D008765:Methylmalonyl-CoA Mutase