Sex pheromone biosynthesis in the pine caterpillar moth, Dendrolimus punctatus (Lepidoptera: Lasiocampidae): pathways leading to Z5-monoene and 5,7-conjugated diene components

Elucidation of the sex-pheromone biosynthesis producing 5,7-dodecadienes in Dendrolimus punctatus (Lepidoptera: Lasiocampidae) reveals Δ11- and Δ9-desaturases with unusual catalytic properties

“…The sex-pheromone components of Dendrolimus punctatus consist of the (Z5,E7)-dodecadienol and the mono-unsaturated (Z)-5-dodecenol (Zhao et al, 1993). In vivo labelling experiments demonstrated that a first D11-desaturation takes place on C 18 to form the Z11-18:acyl (Zhao et al, 2004). Labelled Z11-18:acyl was incorporated into Z5-and Z5,E7-12:acyl and the corresponding alcohols, indicating that the Z5-12:OH is likely formed by D11-desaturation followed by three cycles of b-oxidation and subsequent reduction (Zhao et al, 2004).…”

“…In contrast, pheromone components found in Thysanoplusia intermixta (Ono et al, 2002), Epiphyas postvittana (Foster and Roelofs, 1990;Liu et al, 2002a) and Lampronia capitella (Liénard et al, 2008) are formed after two sequential desaturation steps. Biochemical studies supported that dienyl compounds found among the Lasiocampidae family are also likely to be synthesized by sequential desaturation (Zhao et al, 2004). Most Lasiocampidae species use sex pheromones with conjugated dodecadiene derivatives with double bond positions fixed at the 5th and 7th carbons, i.e., a D5,D7-12:X chemical theme (e.g., Underhill et al, 1980;Ando et al, 1982;Zhao et al, 1993;Klun et al, 2000;Rotundo et al, 2004;Haynes et al, 2007;Kong et al, 2007 and references therein).…”

“…In vivo labelling experiments demonstrated that a first D11-desaturation takes place on C 18 to form the Z11-18:acyl (Zhao et al, 2004). Labelled Z11-18:acyl was incorporated into Z5-and Z5,E7-12:acyl and the corresponding alcohols, indicating that the Z5-12:OH is likely formed by D11-desaturation followed by three cycles of b-oxidation and subsequent reduction (Zhao et al, 2004). Which of the three potential mono-unsaturated substrates, i.e., Z9-16:acyl, Z7-14:acyl or Z5-12:acyl, is actually the substrate for the second desaturation producing the E double bond could not be conclusively evidenced in vivo.…”

Functional characterization of a desaturase from the tobacco hornworm moth (Manduca sexta) with bifunctional Z11- and 10,12-desaturase activity

“…An earlier view which maintains that every female pheromone component is produced by a distinct desaturase (e.g., Yoshiga et al, 2000) is no longer fully accepted. It is now evident that some desaturases use diverse precursor pools and produce diverse pheromonal blends in a parallel fashion (Martinez et al, 1990;Rodriguez et al, 2004;Zhao et al, 2004). Desaturases that catalyze the formation of conjugated dienes by a stepwise conversion of fatty acid (FA) intermediate into the final diene product (Zhao et al, 2004;Moto et al, 2004;Serra et al, 2006) have also been described.…”

“…Desaturases can display both 1,2-and 1,4-desaturation mechanisms. Examples of 1,2-desaturation mechanisms have been discovered in Dendrolimus punctatus (Zhao et al, 2004) and in Spodoptera litoralis (Martinez et al, 1990;Rodriguez et al, 2004). The stereochemistry as well as the cryptochemistry of desaturation in S. litoralis has been fully established and described in detail (Abad et al, 2001;Rodriguez et al, 2002).…”