Regulation of acetohydroxy acid synthase activities in Escherichia coli K-12 by small metabolites

The effects of several metabolites (indole acetic acid, imidazole acetic acid and indole) on acetohydroxy acid synthase activities have been examined in both cya+ and cya- strains. Specifically, indole acetic acid caused an increase in the rate of acetohydroxy acid synthase synthesis under both in vivo and in vitro conditions. Taken together, these data suggest that small metabolites, other than cAMP, can alter acetohydroxy acid synthase gene expression.