Identification of Lrp-regulated genes by inverse PCR and sequencing: regulation of two mal operons of Escherichia coli by leucine-responsive regulatory protein

We have used the technique of inverse PCR to identify Escherichia coli chromosomal genes carrying Lrp-regulated inserts. This technique revealed that malT, malEFG, and malB-lamB-malK are all activated two- to fivefold by Lrp and confirmed that Lrp regulates expression of the leuDBCA and livHJKG operons. lacZ transcription is also increased in the presence of Lrp. However, the growth rate of the Lrp mutant on maltose and lactose is not decreased by Lrp deficiency.