Abstract
The incorporation of acetate-1-14C into lipid fractions in baker's yeast, Saccharomyces cerevisiae, grown in pantothenate-deficient (10μg/liter) medium, has been compared with that of the vitamin-sufficient (200μg/liter) yeast. In the vitamin-deficient yeast (I) acetate-1-14C was incorporated mainly into unsaturated fatty acids e. g. C16:1, C18:1, whereas in the vitamin-sufficient yeast it was incorporated mainly into saturated fatty acids e. g. C16:0, C18:0, (II) the incorporation of acetate-1-14C into sterol and triglyceride decreased and the level of free 14C-fatty acid was relatively higher than that in the vitamin-sufficient yeast. 32P-Phospholipid in yeast grown in medium containing 32P-phosphate was analyzed. In pantothenate-deficient yeast at the exponential phase, 32P-phosphatidyl choline and 32P-phosphatidyl ethanolamine were reduced one fourth and one third, respectively, of those in the vitamin-sufficient yeast. In pantothenatedeficient yeast much of oleic acid was found at the 2-position of phosphatidyl choline and at the 1- and 2-positions of phosphatidyl ethanolamine.