Studies in carotenogenesis. 30. The problem of lycopersene formation in Neurospora crassa

Abstract

An analysis of the less polar hydrocarbons of the unsaponifiable fraction of N. crassa cultured in the presence of diphenylamine has revealed the presence of squalene, phytoene, phytofluene and [theta]-carotene. Several unidentified hydrocarbons, less polar than squalene, have also been detected, but lycopersene, the C40 analogue of squalene, was absent. [2-14C]Mevalonic acid was significantly incorporated into squalene and phytoene and other tetraterpenes more unsaturated than phytoene. Labelled lycopersene could not be detected. These results indicate that in N. crassa, as in other carotenogenic organisms, phytoene, and not lycopersene, is the first C40 compound formed in carotenoid biosynthesis.