Acetate overflow metabolism regulates a major metabolic shift after glucose depletion in <i>Escherichia</i> <i>coli</i>

Acetate overflow refers to the metabolism by which a large part of carbon incorporated as glucose into Escherichia coli cells is catabolized and excreted acetate medium. We previously found that mutants for pathway enzymes phosphoacetyltransferase (Pta) kinase (AckA) showed significant diauxic growth after depletion in E. coli. Here, we analyzed underlying mechanism pta mutant. Proteomic other analyses revealed an increase pyruvate dehydrogenase complex subunits decrease glyoxylate shunt enzymes, resulted from accumulation. Since restoration these enzyme levels overexpressing PdhR (pyruvate-sensing transcription factor) or deleting iclR (gene encoding pyruvate- glyoxylate-sensing alleviated lag mutant depletion, changes were considered reason phenotype. Given evidence decreased coenzyme A (HS-CoA) mutant, inhibition was partly explained limited availability HS-CoA cell. The findings provide insights role metabolic regulation, may be useful biotechnological applications.