The Leucine-Responsive Regulatory Protein, Lrp, Modulates Microcin Exporter

BENJAMÍN SOCÍAS; PAULA A. VINCENT; RAÚL SALOMÓN

JOURNAL OF BACTERIOLOGY

AMER SOC MICROBIOLOGY

Año: 2009 vol. 191 p. 1343 - 1348

0021-9193

Many Escherichia coli K-12 strains display an intrinsic resistance to the peptide antibiotic microcin J25. In this study, we present results showing that the leucine-responsive regulatory protein, Lrp, is involved in this phenotype by acting as a positive regulator of YojI, a chromosomally encoded efflux pump which expels microcin out of cells. Exogenous leucine antagonizes the effect of Lrp, leading to a diminished expression of the pump and an increased susceptibility to microcin J25.