11 - Pheromone biosynthesis in social insects

Abstract

This chapter focuses on the major advances made in social insect pheromones since 1998 with particular attention to the biosynthetic aspects. Many of the pheromone components in social insects are derived from the chain elongation or chain shortening of fatty acids or from the isoprenoid pathway. Chain elongation of appropriate fatty acids followed by the loss of carboxyl carbon leads to the formation of hydrocarbons that function widely in chemical communication in the social insects. The chapter also reviews a set of experiments related to the biosynthesis of honeybee queen mandibular pheromone (QMP), which occurs by chain shortening after hydroxylation of a fatty acid. The QMP contains major components, 9-hydroxy- and 9-keto-2(E)-decenoic acids. Stearic acid was shown to be the main precursor of the pheromone molecules, as it was converted to C10 hydroxy acids and diacids more efficiently than either 16 or 14 carbon fatty acids.