THE LIPID COMPOSITION OF MICROCOCCUS HALODENITRIFICANS AS INFLUENCED BY SALT CONCENTRATION

Abstract

Cells of M. halodentitrificans grown in 1.0 M NaCl contained 11 ± 2% total lipids, of which about half was phosphatide. Seven lipid components were detected by chromatography, two of which were tentatively identified as phosphatidyl ethanolamine and phosphatidyl glycerol; lecithin was completely absent. No qualitative changes were found in the phospholipid or fatty acid constituents of cells grown in media containing different concentrations of sodium chloride, but cells grown in low salt concentration (0.6 M and 0.55 M) contained 7 to 10 times more unsaponifiable matter than cells grown at the optimal salt concentration (1.0 M). However, the addition of calcium, magnesium, or potassium to low-salt media restored the amount of unsaponifiable matter in cells to normal.