Effect of substrate on the fatty acid composition of hydrocarbon-utilizing filamentous fungi.

The fatty acid pattern in hydrocarbon-utilizing filamentous fungi was determined after growth on acetate, propionate, n-alkanes (C(13) to C(15)), and alk-1-enes (C(14) to C(18)). The fatty acid profile of Cunninghamella elegans and Penicillium zonatum after growth on acetate shows a predominance of even-carbon fatty acids (C(16), C(18:1), C(18:2)), whereas cells grown on propionate showed significantly higher levels of odd-carbon fatty acids (C(15), C(17), C(17:1)). Growth on n-alkanes resulted in the incorporation of fatty acids homologous to the growth substrate. Cunninghamella elegans grown on the alk-1-enes from C(14) to C(18) incorporated the unsaturated substrate into cellular fatty acid after oxidation at the saturated end of the molecule. Regardless of substrate these fungi contain, predominantly, fatty acids 18 carbons in length.