|Synonyms: QseB-Phosphorylated, QseB|
QseB, quorum-sensing E. coli regulator B , is the response regulator component of the QseB-QseC two-component system, which is one component of the quorum-sensing regulatory cascade involved in the positive regulation of flagella and motility genes by activating transcription of flhDC, an operon that encodes the master regulator of these genes |CITS: |.
This protein also may have an undetermined role in metal metabolism, because qseBC deletion mutants show hypersensitivity to several toxic cations |CITS: |.
QseB and QseC of enterohemorrhagic E. coli (EHEC) and of E. coli K-12 are almost identical; there are only three amino acid differences in QseB and only eight amino acid differences in QseC between these strains |CITS: |. It was demonstrated in EHEC that QseC directly senses and binds the bacterial hormone-like AI-3 signal and the host epineprhine/norepineprhine hormones, and it causes the autophosphorylation of QseC, which then transfers the phosphate group to QseB to activate it |CITS: |.
The expression of the operon containing both genes qseB, encoding the response regulator, and qseC, encoding the sensor kinase, is regulated by a quorum-sensing system |CITS: |, and the regulatory region of the operon is 99.6% identical to the regulatory region of the same operon in EHEC |CITS: |.
|Sensing class:||External-Two-component systems|
|Connectivity class:||Local Regulator|
|Length:||660 bp / 219 aa|
|TU(s) encoding the TF:||
|Regulated gene(s)||flhC, flhD, qseB, qseC|
|Multifun term(s) of regulated gene(s)||
MultiFun Term (List of genes associated to the multifun term)
Transcription related (3)
flhC, flhD, qseB
flhC, flhD, qseB
motility, chemotaxis, energytaxis (aerotaxis, redoxtaxis etc) (2)
two component regulatory systems (external signal) (2)
posttranslational modification (1)
covalent modification, demodification, maturation (1)
|Regulated operon(s)||flhDC, qseBC|
|First gene in the operon(s)||flhD, qseB|
|Simple and complex regulons|
|Simple and complex regulatory phrases||
Regulatory phrase (List of promoters regulated by the phrase)
|Functional conformation||Function||Promoter||Sigma factor||Central Rel-Pos||Distance to first Gene||Genes||Sequence||LeftPos||RightPos||Evidence (Confirmed, Strong, Weak)||References|
|3169281||3169293||[BPP], [GEA]||, |
|3169748||3169760||[BPP], [GEA]||, |
|Evolutionary conservation of regulatory elements|
 Sperandio V., Torres AG., Kaper JB., 2002, Quorum sensing Escherichia coli regulators B and C (QseBC): a novel two-component regulatory system involved in the regulation of flagella and motility by quorum sensing in E. coli., Mol Microbiol. 43(3):809-21