Abstract
An examination was made of the effects of metal ions and temperature on the lipid composition of Mortierella ramanniana var. angulispora, a lipid-producing fungus. In a concentration range not affecting cell growth, an increase in Zn2+ mainly caused increase in unsaturated fatty acids such as linoleic and γ-linolenic acids of polar lipids, but not neutral lipids. However, Fe2+ acted on neutral lipids rather than polar lipids, especially in regard to γ-linolenic acid content. Lowering the temperature led to increase in the γ-linolenic acid of polar lipis. Enzyme systems which modulate the fatty acid composition of polar and neutral lipids of this fungus, especially those determining γ-linolenic acid content, appear to differ or each to be regulated in a unique way.
