CARBONS FROM CHOLINE PRESENT IN THE PHOSPHOLIPIDS OF PSEUDOMONAS-AERUGINOSA

The phospholipid composition of Pseudomonas aeruginosa grown in a mine ral medium with choline as the carbon source was: phosphatidylethanola mine, 71.6+/-1.4%; phosphatidylglycerol, 11.8+/-0.4%; diphosphatidylgl ycerol, 0.8+/-0.4%; phosphatidic acid, 2.4 +/- 0.6%; lysophosphatidyle thanolamine, 1.6 +/- 0.3%; phosphatidylcholine 7.9 +/- 0.3%; lysophosp hatidylcholine, 3.9 +/- 0.7%. The molar ratio between the acidic and t he neutral phospholipids was 0.18. Radiolabeling experiments with [met hyl-C-14]choline or [1,2-C-14]choline carried out in cell suspension f rom bacteria that were grown in the presence of choline as the sole ca rbon source demonstrated that the carbons of the N-methyl groups of ch oline contributed to the synthesis of fatty acids while the carbons co mprising the backbone of choline were used for the synthesis of glycer ol.