The quorum sensing negative regulators EsaR and ExpR(Ecc), homologues within the LuxR family, retain the ability to function as activators of transcription.
Most LuxR homologues function as activators of transcription during the process of quorum sensing, but a few, including EsaR and ExpR(Ecc), negatively impact gene expression. The LuxR-activated luxI promoter and LuxR binding site, the lux box, were used in artificial contexts to assess the potential for transcriptional activation and DNA binding by EsaR and ExpR(Ecc). Although the acyl-homoserine lactone responsiveness of both proteins is the opposite of that shown by most LuxR family members, EsaR and ExpR(Ecc) have preserved the ability to interact with RNA polymerase and activate transcription despite their low affinity for the lux box DNA.
von Bodman
Susanne B
SB
Department of Plant Science, University of Connecticut, Storrs, Connecticut 06269, USA.
Ball
Jessica K
JK
Faini
Marie A
MA
Herrera
Carmen M
CM
Minogue
Timothy D
TD
Urbanowski
Mark L
ML
Stevens
Ann M
AM
D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D004269:DNA, Bacterial / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics* / Q000502:physiology; D015964:Gene Expression Regulation, Bacterial; D009876:Operon; D012097:Repressor Proteins / Q000235:genetics* / Q000378:metabolism; D015534:Trans-Activators / Q000235:genetics* / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism; D014158:Transcription, Genetic
D001426:Bacterial Proteins; D004269:DNA, Bacterial; D004268:DNA-Binding Proteins; C095459:EsaR protein, Pantoea stewartii; C115748:ExpR protein, Erwinia; D012097:Repressor Proteins; D015534:Trans-Activators; D014157:Transcription Factors; C064778:LuxR autoinducer binding proteins