Incorporation of [1-14C]acetate into fatty acids and aliphatic moieties of glycerolipids in Leishmania donov ani promastigotes

Abstract

1. Short-time incubations (20-300 sec) of Leishmania donovani with [1-14C] acetate showed lauric, myristic and palmitic acid to be labeled first, whereas from 150 sec on the radioactivity was mainly found in stearic and oleic acid. 2. After an incubation period of 7 days the distribution of radioactivity in fatty acids was similar to the mass distribution of fatty acids. 3. Up to 300 sec 14C-activity was present mainly in acyl moieties of lipids (94%). 4. Ether moieties of radylglycerols, diradylglycerophosphoethanolamine and -inositol slowly incorporated radioactivity in pulse-chase experiments from 1 to 24 hr. 5. Pulse-chase experiments revealed significant differences in plasmanylethanolamine, acylglycerol and sterol metabolism of cells in the logarithmic or stationary phase of growth.