HyfR , hydrogenase four regulator, controls the expression of genes responsible for the proton-translocating formate hydrogenase system and for formate transport under anaerobiosis, low pH, and post-exponential growth conditions |CITS:[ 9387241]|.
As a member of the group of σ54-dependent transcriptional regulators, HyfR contains three domains: the sensory domain, located in the N terminus; the central domain, involved in open complex formation, ATP hydrolysis, and interaction with σ54, and the C-terminal domain, which contains a helix-turn-helix motif for DNA binding |CITS:[ 9387241]|. An iron-sulfur cluster and a metal cofactor (possibly a similar metal or formate) have been proposed as the signals sensed by HyfR |CITS:|.
HyfR shows 46% identity to FhlA, a member of the same group. These proteins are dissimilar in their N-terminal regions, which in FhlA recognizes formate. However, they show only one different residue in their helix-turn-helix motif, suggesting that they recognize similar DNA-binding sites |CITS:|.
The HyfR protein is autoregulated. The gene that codes for it is the 11th in the hyf operon, which contains 12 genes that are not expressed at significant levels. This operon is induced under anaerobiosis, at low pH, and under fermentative conditions by formate, and it is subject to catabolite repression |CITS:[ 12426353]|.
|Connectivity class:||Local Regulator|
|Length:||2013 bp / 670 aa|
|TU(s) encoding the TF:||
|Regulated gene(s)||focB, hyfA, hyfB, hyfC, hyfD, hyfE, hyfF, hyfG, hyfH, hyfI, hyfJ, hyfR|
|Multifun term(s) of regulated gene(s)||
MultiFun Term (List of genes associated to the multifun term)
anaerobic respiration (10)
hyfA, hyfB, hyfC, hyfD, hyfE, hyfF, hyfG, hyfH, hyfI, hyfR
focB, hyfB, hyfC, hyfD, hyfE, hyfF
Porters (Uni-, Sym- and Antiporters) (1)
protein related (1)
Transcription related (1)
hyfRRead more >
|First gene in the operon(s)||hyfA|
|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|
|HyfR||activator||hyfAp||Sigma54||-129.5||-159.5||hyfA, hyfB, hyfC, hyfD, hyfE, hyfF, hyfG, hyfH, hyfI, hyfJ, hyfR, focB||
|2601033||2601050||[AIBSCS], [GEA]||, |
|Evolutionary conservation of regulatory elements|
 Skibinski DA., Golby P., Chang YS., Sargent F., Hoffman R., Harper R., Guest JR., Attwood MM., Berks BC., Andrews SC., 2002, Regulation of the hydrogenase-4 operon of Escherichia coli by the sigma(54)-dependent transcriptional activators FhlA and HyfR., J Bacteriol. 184(23):6642-53