Bacillus subtilis LmrA is a repressor of the lmrAB and yxaGH operons: identification of its binding site and functional analysis of lmrB and yxaGH

J Bacteriol. 2004 Sep;186(17):5640-8. doi: 10.1128/JB.186.17.5640-5648.2004.


The Bacillus subtilis lmrAB operon is involved in multidrug resistance. LmrA is a repressor of its own operon, while LmrB acts as a multidrug efflux transporter. LmrA was produced in Escherichia coli cells and was shown to bind to the lmr promoter region, in which an LmrA-binding site was identified. Genome-wide screening involving DNA microarray analysis allowed us to conclude that LmrA also repressed yxaGH, which was not likely to contribute to the multidrug resistance. LmrA bound to a putative yxaGH promoter region, in which two tandem LmrA-binding sites were identified. The LmrA regulon was thus determined to comprise lmrAB and yxaGH. All three LmrA-binding sites contained an 18-bp consensus sequence, TAGACCRKTCWMTATAWT, which could play an important role in LmrA binding.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Bacillus subtilis / genetics*
  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism
  • Bacterial Proteins / physiology
  • Base Sequence
  • Binding Sites
  • Cloning, Molecular
  • Consensus Sequence
  • Escherichia coli / genetics
  • Escherichia coli / metabolism
  • Gene Expression Profiling
  • Gene Expression Regulation, Bacterial*
  • Molecular Sequence Data
  • Multidrug Resistance-Associated Proteins / genetics
  • Multidrug Resistance-Associated Proteins / physiology*
  • Oligonucleotide Array Sequence Analysis
  • Operon
  • Promoter Regions, Genetic
  • Protein Binding
  • Recombinant Proteins / genetics
  • Recombinant Proteins / isolation & purification
  • Recombinant Proteins / metabolism
  • Regulon
  • Repressor Proteins / genetics
  • Repressor Proteins / metabolism*
  • Repressor Proteins / physiology*


  • Bacterial Proteins
  • Multidrug Resistance-Associated Proteins
  • Recombinant Proteins
  • Repressor Proteins