Alterations in Fatty Acid Metabolism and Morphology of Leishmania enriettii Exposed to Elevated Temperature

SYNOPSIS. Cytoplasmic inclusions appear rapidly in Leishmania enriettii exposed to 37 C. The staining of these droplets with oil red O, their extraction in non‐polar solvents, and their fine structure by electron microscopy establish their identity as lipid droplets. Fatty acid profiles of these organisms show alterations concomitant with the development of these inclusions. Oleic acid increases while linolenic acid is depressed in cells exposed to elevated temperature. A greater incorporation of exogenous radioactive stearic acid occurs, with depressed specific activities of linoleic and linolenic acids compared to values obtained with control organisms. The isolated lipids of L. enriettii have temperature‐dependent changes consistent with a physical interpretation of events which occur with temperature inactivation. The temperature lability of fatty acid metabolism is discussed in terms of the synthesis and stability of cellular membranes and organelles.