The EmrR Protein Represses the Escherichia coli emrRAB Multidrug Resistance Operon by Directly Binding to Its Promoter Region

EmrR negatively regulates the transcription of the multidrug resistance pump-encoding operon, emrRAB, by binding to its regulatory region. The binding site spans the promoter and the downstream sequence up to the transcriptional start site of the operon. Structurally unrelated drugs that induce the pump interfere with this binding.