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EnvR DNA-binding transcriptional repressor

Synonyms: EnvR
EnvR, also known as AcrS, represses the transcription of genes encoding a drug efflux pump that has a role in resistance to antibiotics [1]
This protein is homologous to some other proteins, such as MtrR of Neisseria gonorrhoeae, TcmR of Streptomyces glaucescens, JadR2 from Streptomyces venezuelae, and AcrR from Escherichia coli [3, 4] All of these proteins, including EnvR, have a helix-turn-helix motif close to the N terminus [3, 4]
EnvR recognizes and binds a 24-bp palindromic DNA sequence [1] The same sequence is also recognized by the transcriptional repressor AcrR [1]
envR is adjacent and divergent in the genome to acrEF, an operon that encodes another drug efflux pump; however, it is not regulated or is only lightly affected by EnvR [1] Both of these transcription units appears to be repressed by HNS [1] Read more >

Transcription factor      
TF conformation(s):
Name Conformation Type TF-Effector Interaction Type Apo/Holo Conformation Evidence (Confirmed, Strong, Weak) References
EnvR     nd nd
Evolutionary Family: TetR/AcrR
Connectivity class: Local Regulator
Gene name: envR
  Genome position: 3412803-3413465
  Length: 663 bp / 220 aa
Operon name: envR
TU(s) encoding the TF:
Transcription unit        Promoter

Regulated gene(s) acrA, acrB
Multifun term(s) of regulated gene(s) MultiFun Term (List of genes associated to the multifun term)
Porters (Uni-, Sym- and Antiporters) (2)
drug resistance/sensitivity (2)
membrane (2)
Regulated operon(s) acrAB
First gene in the operon(s) acrA
Simple and complex regulons AcrR,EnvR,MarA,MprA,PhoP,Rob,SoxS
Simple and complex regulatory phrases Regulatory phrase (List of promoters regulated by the phrase)

Transcription factor binding sites (TFBSs) arrangements       

  Functional conformation Function Promoter Sigma factor Central Rel-Pos Distance to first Gene Genes Sequence LeftPos RightPos Evidence (Confirmed, Strong, Weak) References
  EnvR repressor acrAp Sigma70 -22.5 -101.5 acrA, acrB
485709 485732 [AIBSCS], [BPP], [GEA] [1], [2]

Evolutionary conservation of regulatory elements    
     Note: Evolutionary conservation of regulatory interactions and promoters is limited to gammaproteobacteria.
Promoter-target gene evolutionary conservation


 [AIBSCS] Automated inference based on similarity to consensus sequences

 [BPP] Binding of purified proteins

 [GEA] Gene expression analysis


 [1] Hirakawa H., Takumi-Kobayashi A., Theisen U., Hirata T., Nishino K., Yamaguchi A., 2008, AcrS/EnvR represses expression of the acrAB multidrug efflux genes in Escherichia coli., J Bacteriol. 190(18):6276-9

 [2] Rodionov DA., Gelfand MS., Mironov AA., Rakhmaninova AB., 2001, Comparative approach to analysis of regulation in complete genomes: multidrug resistance systems in gamma-proteobacteria., J Mol Microbiol Biotechnol. 3(2):319-24

 [3] Yang K., Han L., Vining LC., 1995, Regulation of jadomycin B production in Streptomyces venezuelae ISP5230: involvement of a repressor gene, jadR2., J Bacteriol. 177(21):6111-7

 [4] Pan W., Spratt BG., 1994, Regulation of the permeability of the gonococcal cell envelope by the mtr system., Mol Microbiol. 11(4):769-75