Fatty Acid Oxidation in Crithidia fasciculata

Abstract

Cultures of the kinetoplastid Crithidia fasciculata at their logarithmic phase of growth oxidize [1-14C]palmitate to α-hydroxy fatty acids, CO2, and water-soluble products. 2-Hydroxy[1-14C]stearate is also decarboxylated. The decarboxylation of [1-14C]palmitate by cells and homogenate decreases in the presence of nonradioactive L-2-hydroxypalmitate, and to a lesser extent in the presence of the D- form. [2-14C]stearate, compared with [1-14C]palmitate, is oxidized to a greater extent into water-soluble products and this process is not affected by nonradioactive DL-2-hydroxystearate.Radioactive peaks corresponding to the mass peaks of odd-chain and α-hydroxy fatty acids have been detected by gas–liquid chromatography after incubation of whole cells or cell fractions with [9,10-3H2]palmitate or stearate.The results suggest the operation of the α-oxidation system for degradation of fatty acids to be via the α-hydroxy intermediate.