VIEW ARTICLE    DOI: 10.1094/ASBCJ-40-0026

Influence of Growth Temperature on the Fatty Acid Composition of the Cytoplasmic Membrane of a Lager Yeast. P. C. Patel and M. J. Lewis, Department of Food Science and Technology, University of California, Davis 95616. J. Am. Soc. Brew. Chem. 40:0026, 1982.

The purified cytoplasmic membrane of a lager brewing yeast contained more phospholipid but less magnesium and calcium when the cells were grown at 10° C than at 20 or 30° C. When the membranes were solubilized in sodium dodecyl sulfate and applied to a Sephadex G-200 column, these differences proved to be mainly in the lower molecular weight fraction of the membrane. The fatty acid composition of whole yeast cells, purified cytoplasmic membranes, and other cell fractions was determined by gas-liquid chromatography. The principal fatty acids, in all cases, were palmitoleic acid, oleic acid, and palmitic acid, which together accounted for over 90% of the total fatty acids. The ratio of unsaturated to saturated fatty acid was the same in whole cells grown at 20 and 30° C (81:19) and in cytoplasmic membrane isolated from them, and it was only slightly greater in cells grown at 10° C (83:17). However, when the yeast growth temperature was lowered from 30 to 20 or 10° C, the proportion of palmitoleic acid in whole cells and the cytoplasmic membrane increased (from 47 to 60%, by weight, of the total fatty acid present), and the proportion of oleic acid decreased equally (from 35 to 23%, by weight). The results suggest an influence of growth temperature on membrane composition that can be related to membrane fluidity and stability.

Keywords: Cytoplasmic membrane, Fatty acids, Growth temperature, Magnesium content, Plasmalemma, Yeast