Abstract
Four independent ace mutants of P. aeruginosa PAO lacking the activity of the pyruvate dehydrogenase complex were isolated. They resembled ace mutants of Escherichia coli and Salmonella typhimurium in requiring acetate as an essential supplement for aerobic growth on glucose, succinate or lactate and in their ability to utilize acetate as sole C and energy source. Assays for the individual components of the pyruvate dehydrogenase complex indicated that they lacked the pyruvate dehydrogenase component (E1) or the pyruvate dehydrogenase and dihydrolipoamide acetyltransferase components (E1 and E2) but not the lipoamide dehydrogenase component (E3). Genetic studies with plasmid R68. 45-mediated conjugation and phage F116L-mediated transduction indicated that the ace mutations are located at approximately 15 min in the P. aeruginosa PAO linkage map.