Carotenoids and Cholesterol in Membranes of Mycoplasma Laidlawii

Abstract

Carotenoids synthesized by M. laidlawii and cholesterol incorporated from the growth medium were confined to the cell membrane. Increased carotenogenesis induced by addition of sodium acetate to the growth medium, or inhibition of carotenogenesis by thallium acetate or diphenylamine did not affect the incorporation of cholesterol into membrane lipids. Growth of the organisms in media with various amounts of cholesterol modified the cholesterol content of the membranes with no significant effect on carotenoid formation. These results indicate that carotenoids do not interfere with the incorporation of cholesterol into M. laidlawii membranes.