Purification and positional specificity of sn-glycerol-3-phosphate acyltransferase from Escherichia coli membranes.

SN-Glycerol-3-phosphate acyltransferase was solubilized from membranes of Escherichia coli B and K-12 and purified on an affinity column of Sepharose 4B coupled with 6-phosphogluconic acid. Phosphatidylglycerol was required for activation and stabilization of the purified enzyme. The acyl residues were exclusively transferred to the position 1 of sn-glycerol 3-phosphate by the enzyme, regardless of whether the acyl-CoA was saturated or unsaturated.