The effect of temperature on glyceryl ethers in Tetrahymena pyriformis W.

The effect of temperature on the ether content of the glycerophospholipids of Tetrahymena pyriformis W was examined. The only ether detected was 1-O-hexadecyl glycerol (alpha-chimyl alcohol). The data provide evidence that the class 1-O-alkyl-2-acyl-sn-glycero-3-(2-aminoethyl)-phosphate (1-alkyl PsE), in addition to the previously reported 1-O-alkyl-2-acyl-sn-glycero-3-(2-aminoethyl)-phosphonate (1-alkyl PnE) and 1-O-alkyl-2-acyl-sn-glycero-3-phosphorylcholine (1-alkyl PC), exists in this ciliate species. A comparison was made of the ether content of the glycerophospholipids from cells grown at 15 degrees and 28.5 degrees C. An elevation in the amount of ether was noted in all glycerophospholipids at the lower temperature with the largest proportional change in 1-alkyl PsE. Tetrahymena species have a high gamma-linolenic acid content in the sn-1 position of the glycerophospholipids in addition to the usual saturated acids and ether. The replacement at low temperature of gamma-linolenic acid by a saturated hydrocarbon at the sn-1 position of the glycerophospholipids of Tetrahymena pyriformis W should increase the microviscosity of the membranes; thus, it is difficult to envision this alteration in the glycerophospholipids as an adaptive change beneficial for growth. These findings are in direct contrast to the situation in Tetrahymena thermophila where the percentage of ether glycerophospholipids increases at the expense of gamma-linolenate as the temperature rises.