Effect of a phosphonic acid analog of choline phosphate on phospholipid metabolism in Tetrahymena

When Tetrahymena thermophila is grown on a medium containing increasing concentrations of N,N,N-trimethyl-2-aminoethylphosphonate (TMAEP), up to 60% of the choline phosphate in phosphatidylcholine is replaced by the phosphonic acid. There is an increase in the relative amount of quaternary ammonium-containing lipid (phosphatidylcholine plus TMAEP-lipid) at the expense of phosphatidylethanolamine. There is no effect of the TMAEP on either 2-aminoethylphosphonolipid levels or on de novo 2-aminoethylphosphonate synthesis. Higher levels of TMAEP in the medium (25 and 50 mm) lead to decreased growth of Tetrahymena and to an abnormal cell morphology.