Loss of Hydrogen from Dihydroxyacetone Phosphate during Glyceryl Ether Synthesis

In order to obtain information on the mechanism of ether bond formation in the synthesis of O-alkyl lipids, a study was carried out to determine if there is a loss of hydrogen from carbon 3 of dihydroxyacetone phosphate (DHAP) (non-phosphorus-linked carbon) in the course of its incorporation into glyceryl ethers. Accordingly, a mixture of [1,3-3H2] DHAP and [1,3-14C2]DHAP was prepared. In a microsomal enzyme system from Tetrahymena pyriformis which synthesizes O-alkyl lipids, it was found that there was a loss of hydrogen from carbon 3 of glyceryl ethers synthesized from double-labeled DHAP. The loss was quantitatively consistent with the labilization of one of the hydrogens linked to carbon 3 of DHAP and was not due to isomerase activity.