FrsA functions as a cofactor-independent decarboxylase to control metabolic flux

Abstract

The interaction between fermentation-respiration switch(FrsA) protein and glucose-specific enzyme IIAGlc increasesglucose fermentation under oxygen-limited conditions. Weshow that FrsA converts pyruvate to acetaldehyde and carbondioxide in a cofactor-independent manner and that its pyruvatedecarboxylation activity is enhanced by the dephosphorylatedform of IIAGlc (d-IIAGlc). Crystal structures of FrsA and itscomplex with d-IIAGlc revealed residues required for catalysisas well as the structural basis for the activation by d-IIAGlc.The bacterial phosphoenolpyruvate:sugar phosphotransferase