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MprA DNA-binding transcriptional repressor

Synonyms: MprA, MprA-2,4-dinitrophenol, MprA-Carbonyl cyanide m-chlorophenylhydrazone (CCCP), MprA-Carbonyl cyanide p-(trifluoro-methoxy)phenylhydrazone
The E. coli multidrug resistance regulator |CITS: [1409590][7730261]|, EmrR, negatively regulates the transcription of genes that code for multidrug resistance pumps that extrude structurally unrelated antimicrobial agents from the cell |CITS: [7730261][11321589]| and possibly it also represses a gene that codes for a porin |CITS: [11321589]|. When EmrR is overexpressed (the emrR gene in multicopy), it is able to repress the marRAB operon, which encodes two transcriptional regulators |CITS: [8521301]|.
EmrR, which is also known as MprA, microcin production regulation, locus A |CITS: [2152912]|, has also been shown to be a repressor of plasmid-encoded genes involved in microcin biosynthesis |CITS: [2152912][1840583][9484896]|. Microcins are low-molecular-weight polypeptide antibiotics |CITS: [4071]|.
The EmrR dimer binds 2,4-dinitrophenol, carbonyl cyanide m-chlorophenylhydrazone (CCCP), and carbonyl cyanide p-(trifluoro-methoxy)phenylhydrazone, predicted ligands of the EmrAB pump, with high affinity |CITS: [10438794]|. Binding of these agents interferes with the ability of EmrR to bind DNA |CITS: [10991887]|. This dimeric protein |CITS: [10438794]| recognizes and binds an imperfect inverted repeat DNA sequence |CITS: [10991887]|.
EmrR belongs to the MarR family of transcriptional regulators |CITS: [8521301]|, which respond to a variety of phenolic compounds and are found in gram-positive and gram-negative species as well as in mycobacteria |CITS: [8521301]|.
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Transcription factor      
TF conformation(s):
Name Conformation Type TF-Effector Interaction Type Apo/Holo Conformation Evidence (Confirmed, Strong, Weak) References
MprA Functional   Apo [BPP], [GEA] [1], [2], [3]
MprA-2,4-dinitrophenol Non-Functional Allosteric Holo [BPP], [GEA] [1], [2], [3]
MprA-Carbonyl cyanide m-chlorophenylhydrazone (CCCP) Non-Functional Allosteric Holo [BPP], [GEA] [1], [2], [3]
MprA-Carbonyl cyanide p-(trifluoro-methoxy)phenylhydrazone Non-Functional Allosteric Holo [BPP], [GEA] [1], [2], [3]
Evolutionary Family: MarR
Connectivity class: Local Regulator
Gene name: mprA
  Genome position: 2810770-2811300
  Length: 531 bp / 176 aa
Operon name: mprA-emrAB
TU(s) encoding the TF:
Transcription unit        Promoter

Regulated gene(s) acrA, acrB, emrA, emrB, mprA, nmpC
Multifun term(s) of regulated gene(s) MultiFun Term (List of genes associated to the multifun term)
drug resistance/sensitivity (5)
Porters (Uni-, Sym- and Antiporters) (4)
membrane (4)
Transcription related (1)
repressor (1)
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Regulated operon(s) acrAB, mprA-emrAB, nmpC
First gene in the operon(s) acrA, mprA, nmpC
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
  MprA repressor acrAp Sigma70 -16.0 -95.0 acrA, acrB
485704 485724 [AIBSCS] [4]
  MprA repressor mprAp Sigma70 -10.0 -33.0 mprA, emrA, emrB
2810727 2810747 [BPP] [3]
  MprA repressor nmpCp nd -161.0 -206.0 nmpC
577021 577041 [AIBSCS] [4]

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


 [BPP] Binding of purified proteins

 [GEA] Gene expression analysis

 [AIBSCS] Automated inference based on similarity to consensus sequences


 [1] 10438794., null, null, null

 [2] Lomovskaya O., Lewis K., Matin A., 1995, EmrR is a negative regulator of the Escherichia coli multidrug resistance pump EmrAB., J Bacteriol. 177(9):2328-34

 [3] Xiong A., Gottman A., Park C., Baetens M., Pandza S., Matin A., 2000, The EmrR protein represses the Escherichia coli emrRAB multidrug resistance operon by directly binding to its promoter region., Antimicrob Agents Chemother. 44(10):2905-7

 [4] 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