Unsaturated fatty acid composition of wild type and respiratory deficient yeasts after aerobic and anaerobic growth

An analysis is given of the fatty acid composition of 18 yeast species, predominantly of the genus Saccharomyces; respiratory deficient mutant strains are included. The results are discussed from chemotaxonomical and physiological viewpoints, with special attention to unsaturated fatty acids and their relation to the petite mutation. The fatty acid composition of anaerobically grown Saccharomyces cerevisiae remains restricted, as far as unsaturated fatty acids are concerned, to those added to the medium and it may thus differ considerably from the composition after aerobic growth. Depending on the acids added, the cells may contain either palmitoleic or linoleic acids as the sole unsaturated fatty acid after anaerobic growth and as the predominant unsaturated fatty acid after aerobic growth. In contrast to all other known eukaryotes, Schizosaccharomyces japonicus seems to possess an anaerobic pathway for synthesis of unsaturated fatty acids.