Activation of the Escherichia coli lacZ promoter by the Klebsiella aerogenes nitrogen assimilation control protein (NAC), a LysR family transcription factor.

A chimeric promoter with the nitrogen assimilation control protein binding site from hutUp of Klebsiella aerogenes fused to the lacZ core promoter from Escherichia coli was built and cloned in a lacZ reporter plasmid. This construct showed a 14-fold increase of beta-galactosidase activity upon nitrogen limitation. Primer extension experiments showed that the nitrogen assimilation control protein activates lacZp1 in a position-dependent manner.