Lipid composition of Agrobacterium wild type, Δagt, and Δagt Δpgt grown under phosphate replete (+P) or depleted (−P) conditions. The bars represent mean values in mol % ± S.D. of three measurements. PE, phosphatidylethanolamine; MMPE, monomethyl-PE; PG, phosphatidylglycerol; CL, cardiolipin; OL-OH, hydroxylated form of OL (4) Lipids were quantified after isolation from the TLC plate, transmethylation, and measurements of fatty acid methyl esters by GC-MS.