Inhibition of Cuticular Lipid Biosynthesis in Pisum sativum by Thiocarbamates.

Treatment of slices of young pea leaves (Pisum sativum) with muM solutions of alpha-chlorallyl diethyldithiocarbamate, dichloroallyl diisopropylthiocarbamate, or S-ethyldipropylthiocarbamate resulted in inhibition of incorporation of [1-(14)C]acetate into C(31) alkane and C(31) secondary alcohol, very little effect on the synthesis of C(26) and C(28) fatty alcohols, and an accumulation of (14)C in shorter chain cuticular lipids, particularly C(22) acid. Higher concentrations of the thiocarbamates caused inhibition of synthesis of C(26) and C(28) fatty alcohols and an accumulation of label in C(22) acid. Further increase in thiocarbamate concentration resulted in inhibition of C(22) acid synthesis also. The three thiocarbamates at muM concentration also inhibited incorporation of [1-(14)C]stearic acid specifically into C(31) alkane and C(31) secondary alcohol. These results suggest that thiocarbamates reduce cuticular lipid formation by a concentration-dependent inhibition of the various chain-elongating enzyme systems.