Metabolism of alkyl glyceryl ethers and their noninvolvement in alkane biosynthesis in plants

Abstract

[1- 14C]Octadecyl glyceryl ether did not label alkanes in the leaves of Brassica oleracea and Pisum sativum while [1- 14C]octadecanol and [1- 14C]octadecanoic acid readily labeled the alkanes. About 40% of the exogenous-labeled glyceryl ether was incorporated intact into choline phosphatide while 10–20% was converted into fatty acids and alcohols. [1- 14C]octadecanol was not converted into alkyl glyceryl ether, but it was oxidized to the corresponding acid and then incorporated into alkanes. These results show that alkyl ether is not an intermediate in alkane biosynthesis. When [1- 14C-1- 3H]-octadecanol was fed to the leaves of B. oleracea and P. sativum, only the 14C and no 3H was incorporated into alkanes, ketones, and secondary alcohols. These results show that fatty alcohols are first oxidized to the acid before being incorporated into alkanes, ruling out fatty alcohol, alkyl ether, and alk-1-enyl ether as intermediates in alkane biosynthesis. The exogenous alcohols were also readily esterified into wax esters in both tissues.