Systematic genome-wide scanning for genes involved in ATP generation in Escherichia coli.

Adenosine 5'-triphosphate (ATP) generation is an essential biological reaction for all living cells. Recently, we developed a Permeable Cell Assay for high-throughput measurement of cellular ATP synthetic activity, mainly resulting from glycolysis [Hara, K.Y., Mori, H., 2006. An efficient method for quantitative determination of cellular ATP synthetic activity. J. Biomol. Screen. 11, 310-317]. By using this method, we determined the cellular ATP synthetic activity in the stationary phase of a complete set of single-gene deletion strains of Escherichia coli. Their activities ranged from a minimum of 2% to a maximum of 445%, relative to parental strains. Deletions of metabolism-related genes frequently caused an increase in the rate of ATP synthetic activity, while activity was reduced by deletions of a variety of functional genes, including many poorly characterized genes. We also demonstrated that the deletion of the ptsG gene doubled ATP-driven glutathione synthesis and increased cellular ATP synthetic activity. Our study also indicated that it should be easy to obtain active strains for ATP synthesis from deletion strains. Overall, the data set of this study may be useful to improve E. coli strains for ATP-dependent industrial processes and, therefore, may be important for the design of so-called cell factories.