Metabolism of the glycosyl diglycerides and phosphatidylglucose of Staphylococcus aureus

Abstract

A glucose containing lipid, phosphatidylglucose (probably 3-sn-phosphatidyl-1'-glucose) and a lipid tentatively identified as phosphatidylethanolamine have been characterized in the lipids of Staphylococcus aureus. These lipids together comprise less than 2% of the total phospholipids of exponentially growing S. aureus and accumulate to 14% of the total phospholipid in stationary-phase cells. These lipids lost no (32)P when cells grown with H(3) (32)PO(4) were transferred to nonradioactive medium during the exponential growth phase. This was in marked contrast to the other phospholipids which lost (32)P rapidly. The loss of (32)P from phosphatidic acid and cardiolipin in exponentially growing cells was biphasic, suggesting heterogeneity of phospholipid phosphate metabolism. The mono- and diglucosyl diglycerides showed a rapid loss of (14)C-glucose during growth in nonradioactive medium but no loss of (14)C from the fatty acids of these lipids. The (14)C in the glucose and fatty acids of the glucosyl diglycerides was derived from glucose.