Identification of proteins whose amounts are altered by mutation in the pgsA gene of Escherichia coli

We identified proteins whose amounts were altered in an Escherichia coli pgsA3 mutant lacking the potential to synthesize phosphatidylglycerolphosphate, a precursor of phosphatidylglycerol. Proteins whose amounts were increased in the mutant were protease Do, periplasmic oligopeptide-binding protein, tryptophanase, and an unidentified protein, while the decreased one was flagellin. Transformation of the mutant with a plasmid containing the wild type pgsA gene complemented the phenotype, indicating that the pgsA3 mutation is responsible for the phenotype.