Purification and ligand binding of EmrR, a regulator of a multidrug transporter.
نویسندگان
چکیده
EmrR, the repressor of the emrRAB operon of Escherichia coli, was purified to 95% homogeneity. EmrR was found to bind putative ligands of the EmrAB pump-2,4-dinitrophenol, carbonyl cyanide m-chlorophenylhydrazone, and carbonyl cyanide p-(trifluoro-methoxy)phenylhydrazone-with affinities in the micromolar range. Equilibrium dialysis experiments suggested one bound ligand per monomer of the dimeric EmrR.
منابع مشابه
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.
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ورودعنوان ژورنال:
- Journal of bacteriology
دوره 181 16 شماره
صفحات -
تاریخ انتشار 1999