Semiochemistry of Orgyia and Diatraea lepidopteran species and affinity labelling of 2,3-oxidosqualene cyclase.

摘要

The first part of this thesis reports the identification and synthesis of female produced insect sex pheromones of Orgyia (Lepidoptera: Lymantriidae) and Diatraea species (Lepidoptera: Pyralidae, Crambinae). In the studies of sex pheromones for Orgyia species, 6(Z),9(Z)-heneicosadien-11-one was identified as a primary sex pheromone component for O. leucostigma, along with 6(Z)-heneicosen-11-one. These identifications have been substantiated by field tests. Seven and two antennally active components have been identified in the female gland extracts of O. antiqua and O. vetusta, respectively. The sex pheromone candidates for O. antiqua, 6(Z)-heneicosen-11-one, 6(Z)-eicosen-11-one and 6(Z)-docosen-11-one have been field tested and resulted in male moth captures.;Several Diatraea species, D. saccharalis, D. crambidoides, D. busckella and D. rosa , from Central and South American countries have been studied and the potential sex pheromones identified, based mainly on GC-EAD techniques. Field tests for D. rosa have been successful in demonstrating attractive sex pheromone components.;The second part of this thesis reports chemical labelling of 2,3-oxidosqualene cyclase, an enzyme responsible for biosynthesis of cholesterol. Two tritium labelled 15,16-epoxy-3,8,12,16-tetramethyl-1-(1,5-dimethyl-4-hexenyl)sulfanyl-3(E),7(E),11(E)-heptadecatrienes (S-18), with tritium strategically placed at 17 and 22 positions of S-18, were synthesized via 16 and 21 step syntheses, respectively. Incubation of these two compounds with pig liver cyclase gave a single radioactive protein band at 75 kDa after sodium dodecyl sulfate-polyacrylamide gel electrophoresis. This result indicates that the active site of OSC at position C(20) of protosterol is capable of being covalently modified.