Synthesis of lipids from [2-14C]acetate and [14C]glucose by Trichoderma viride

Abstract

Phospholipids closely followed by triglycerides had higher specific activities than the free fatty acids in the lipid obtained from 4-day-old Trichoderma mycelium that had been grown for 1, 3 or 5 hr. in the presence of [2-l4c]acetate. After only 1 hr. in the presence of labelled acetate, radioactive carbon was found in all the long-chain fatty acids, especially oleic acid and palmitic acid, in all 3 major fractions of the lipid. When the 4-day-old mycelium containing high-specific-activity palmitic acid and oleic acid was transferred to unlabelled substrate there was slight indication of conversion of these acids into linoleic acid and linolenic acid. When 2-day-old mycelium, containing high-specific-activity palmitic acid and oleic acid (this activity was obtained from either [14C]acetate or [14c]glucose), was transferred to an unlabelled medium for 2 days the specific activity of linoleic acid (representing 40-50% of the fatty acids present), which was always initially very low, rose to a value equal to the activities of palmitic acid and oleic acid.