Members of this protein family are PlsB, glycerol-3-phosphate O-acyltransferase, present in E. coli and numerous related species. In many bacteria, PlsB is not found, and appears to be replaced by a two enzyme system for 1-acyl-glycerol-3-phosphate biosynthesis, the PlsX/Y system. [Fatty acid and phospholipid metabolism, Biosynthesis]