Effect of Pantothenic Acid Deficiency on Lipid Metabolism in Yeast

II. Influence of Pantothenic Acid Deficiency on Neutral Fats and Phospholipids

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. C_16:1, C_18:1, whereas in the vitamin-sufficient yeast it was incorporated mainly into saturated fatty acids e. g. C_16:0, C_18:0, (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.