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| | dnaK | Chaperone Hsp70, with co-chaperone DnaJ; Plays an essential role in the initiation of phage lambda DNA replication, where it acts in an ATP-dependent fashion with the DnaJ protein to release lambda O and P proteins from the preprimosomal complex. DnaK is also involved in chromosomal DNA replication, possibly through an analogous interaction with the DnaA protein. Also participates actively in the response to hyperosmotic shock. (638 aa) |
| | dnaJ | Chaperone Hsp40, DnaK co-chaperone; Interacts with DnaK and GrpE to disassemble a protein complex at the origins of replication of phage lambda and several plasmids. Participates actively in the response to hyperosmotic and heat shock by preventing the aggregation of stress-denatured proteins and by disaggregating proteins, also in an autonomous, DnaK-independent fashion. Unfolded proteins bind initially to DnaJ; upon interaction with the DnaJ-bound protein, DnaK hydrolyzes its bound ATP, resulting in the formation of a stable complex. GrpE releases ADP from DnaK; ATP binding to DnaK t [...] (376 aa) |
| | araC | Ara regulon transcriptional activator; Transcription factor that regulates the expression of several genes involved in the transport and metabolism of L-arabinose. Functions both as a positive and a negative regulator. In the presence of arabinose, activates the expression of the araBAD, araE, araFGH and araJ promoters. In the absence of arabinose, negatively regulates the araBAD operon. Represses its own transcription. Acts by binding directly to DNA. (292 aa) |
| | sgrR | Transcriptional DNA-binding transcriptional activator of sgrS sRNA; Activates the small RNA gene sgrS under glucose-phosphate stress conditions as well as yfdZ. Represses its own transcription under both stress and non-stress conditions; this repression likely provides one measure of control over sgrR at the level of synthesis. Might act as a sensor of the intracellular accumulation of phosphoglucose by binding these molecules in its C-terminal solute- binding domain. (551 aa) |
| | mraZ | RsmH methytransferase inhibitor; Negatively regulates its own expression and that of the subsequent genes in the proximal part of the division and cell wall (dcw) gene cluster. Acts by binding directly to DNA. May also regulate the expression of genes outside the dcw cluster; Belongs to the MraZ family. (152 aa) |
| | pdhR | Pyruvate dehydrogenase complex repressor; Transcriptional repressor for the pyruvate dehydrogenase complex genes aceEF and lpd. (254 aa) |
| | yafQ | mRNA interferase toxin of toxin-antitoxin pair YafQ/DinJ; Toxic component of a type II toxin-antitoxin (TA) system. A sequence-specific mRNA endoribonuclease that inhibits translation elongation and induces bacterial stasis. Cleavage occurs between the second and third residue of the Lys codon followed by a G or A (5'AAA(G/A)3'), is reading-frame dependent and occurs within the 5' end of most mRNAs. Ribosome-binding confers the sequence specificity and reading frame- dependence. When overexpressed in liquid media YafQ partially inhibits protein synthesis, with a reduction in growth rat [...] (92 aa) |
| | dinJ | Antitoxin of YafQ-DinJ toxin-antitoxin system; Antitoxin component of a type II toxin-antitoxin (TA) system. A labile antitoxin that counteracts the effect of cognate toxin YafQ. YafQ and DinJ together bind their own promoter, and repress its expression. There are 2 operators with imperfect inverted repeats (IR) in the dinJ promoter, YafQ-(DinJ)2-YafQ only binds to the first (most upstream) of them to repress transcription; binding to a single IR is sufficient for activity in vivo and in vitro. DinJ alone is as potent a transcriptional repressor as the heterotetramer and also only need [...] (86 aa) |
| | yagI | CP4-6 prophage; Involved in regulation of xylonate catabolism. Represses the expression of both yagA and yagEF operons. Binds mainly at a single site within the spacer of the bidirectional transcription units yagA and yagEF. (252 aa) |
| | betI | Choline-inducible betIBA-betT divergent operon transcriptional repressor; Repressor involved in the biosynthesis of the osmoprotectant glycine betaine. It represses transcription of the choline transporter BetT and the genes of BetAB involved in the synthesis of glycine betaine. (195 aa) |
| | prpR | Propionate catabolism operon regulatory protein; Involved in the transcriptional regulation of the propionate catabolism operon. (528 aa) |
| | lacI | Lactose-inducible lac operon transcriptional repressor; Repressor of the lactose operon. Binds allolactose as an inducer. (360 aa) |
| | mhpR | Mhp operon transcriptional activator; Activator of the mhpABCDFE operon coding for components of the 3-hydroxyphenylpropionate degradation pathway. (277 aa) |
| | frmR | Regulator protein that represses frmRAB operon; Repressor of the frmRAB operon. (91 aa) |
| | nrdR | Nrd regulon repressor; Represses transcription of the class Ib RNR genes nrdHIEF but has much smaller effect on transcription of the class Ia RNR genes nrdAB and class III RNR genes nrdDG. By binding to nrdR boxes in the promoter regions to alter promoter activity, nrdR differentially regulates nrdAB, nrdHIEF and nrdD transcription in aerobic growth. (149 aa) |
| | acrR | Transcriptional repressor; Potential regulator protein for the acrAB genes. (215 aa) |
| | allR | Glyoxylate-inducible transcriptional repressor of all and gcl operons; Negative regulator of allantoin and glyoxylate utilization operons. Binds to the gcl promoter and to the allS-allA intergenic region. Binding to DNA is abolished by glyoxylate. (271 aa) |
| | quuD | DLP12 prophage; Positively regulate expression of some phage genes. Bacterial host RNA polymerase modified by antitermination proteins transcribes through termination sites that otherwise prevent expression of the regulated genes (By similarity); Belongs to the phage antitermination Q type 1 family. (127 aa) |
| | cspE | Cold shock protein; Protein involved in transcription activator activity, transcription and response to temperature stimulus. (69 aa) |
| | fur | Ferric iron uptake regulon transcriptional repressor; Acts as a global negative controlling element, employing Fe(2+) as a cofactor to bind the operator of the repressed genes. Regulates the expression of several outer-membrane proteins including the iron transport operon; Belongs to the Fur family. (148 aa) |
| | mngR | Transcriptional repressor for the mannosyl-D-glycerate catabolic operon; Represses mngA and mngB. Regulates its own expression. (240 aa) |
| | modE | Transcriptional repressor for the molybdenum transport operon modABC; Functions as an intracellular molybdate sensor. The ModE-Mo complex acts as a repressor of the modABC operon, which is involved in the transport of molybdate. Binds modA promoter DNA in the absence of molybdate, however molybdate binding confers increased DNA affinity. Binds the promoter of moaA activating its transcription; binding is not enhanced by molybdate. The protein dimer binds the consensus palindrome sequence 5'-TATAT-N7-TAYAT-3' and a variant 5'-TGTGT-N7-TGYGT-3'. Acts as a regulator of the expression of 6 [...] (262 aa) |
| | ybiH | DUF1956 domain-containing tetR family putative transcriptional regulator; Regulates transcription of the cecR-ybhGFSR operon and the rhlE gene, which altogether are involved in the control of sensitivity to cefoperazone and chloramphenicol. Represses the cecR-ybhGFSR operon and activates the rhlE operon. Acts by binding to a palindromic sequence within the intergenic spacer located between these two divergently transcribed operons. (223 aa) |
| | mntR | Mn(2+)-responsive manganese regulon transcriptional regulator; In the presence of manganese, represses expression of mntH and mntS. Up-regulates expression of mntP. (155 aa) |
| | deoR | Deoxyribose-5-phosphate-inducible deoxyribose operon transcriptional repressor; This protein is one of the repressors that regulate the expression of deoCABD genes, which encode nucleotide and deoxy ribonucleotide catabolizing enzymes. It also negatively regulates the expression of nupG (a transport protein) and tsx (a pore-forming protein). The inducer is deoxyribose-5-phosphate. (252 aa) |
| | lrp | Leucine-responsive global transcriptional regulator; Mediates a global response to leucine. Exogenous leucine affects the expression of a number of different operons; lrp mediates this effect for at least some of these operons. For example it is regulator of the branched-chain amino acid transport genes. (164 aa) |
| | cspH | Stress protein, member of the CspA-family; Cold shock-like protein; Protein involved in response to temperature stimulus. (70 aa) |
| | cspG | Homolog of Salmonella cold shock protein; Protein involved in response to temperature stimulus. (70 aa) |
| | rutR | Rut operon transcriptional repressor for; Master transcription regulator which represses the degradation of pyrimidines (rutABCDEFG) and purines (gcl operon) for maintenance of metabolic balance between pyrimidines and purines. It also regulates the synthesis of pyrimidine nucleotides and arginine from glutamine (carAB) and the supply of glutamate (gadABWX). (212 aa) |
| | putA | Delta-1-pyrroline-5-carboxylate dehydrogenase; Oxidizes proline to glutamate for use as a carbon and nitrogen source and also function as a transcriptional repressor of the put operon; In the C-terminal section; belongs to the aldehyde dehydrogenase family. (1320 aa) |
| | csgD | csgBAC operon transcriptional regulator; The master regulator for adhesive curli fimbriae expression; necessary for transcription of the csgBAC/ymdA operon. Plays a positive role in biofilm formation. May have the capability to respond to starvation and/or high cell density by activating csgBA transcription. Low-level constitutive expression confers an adherent curli fimbriae- expressing phenotype, up-regulates 10 genes and down-regulates 14 others. (216 aa) |
| | flgM | Anti-sigma factor for FliA (sigma 28); Responsible for the coupling of flagellin expression to flagellar assembly by preventing expression of the flagellin genes when a component of the middle class of proteins is defective. It negatively regulates flagellar genes by inhibiting the activity of FliA by directly binding to FliA; Belongs to the FlgM family. (97 aa) |
| | ycfQ | Repressor for bhsA(ycfR); Represses expression of BhsA/ComC by binding to its promoter region in the absence of copper. (210 aa) |
| | bluR | Repressor of blue light-responsive genes; Controls the expression of several small proteins that may play a role in biofilm maturation. Binds to and represses the operator of the ycgZ-ymgA-ariR-ymgC operon and also regulates ynaK. Binding is antagonized by BluF upon blue light (470 nm) irradiation. Blue light may increase the affinity of BluF for BluR, allowing it to be released from its operator. (243 aa) |
| | ycgZ | RcsB connector protein for regulation of biofilm and acid-resistance; Probably a connector protein for RcsB/C regulation of biofilm formation, providing additional signal input into the two-component signaling pathway. Partially antagonizes the activities of YmgA and AriR, proteins that, via the Rcs phosphorelay, promote the synthesis of colanic acid, an exopolysaccharide and matrix component. (78 aa) |
| | fadR | Fatty acid metabolism regulon transcriptional regulator; Multifunctional regulator of fatty acid metabolism. Represses transcription of at least eight genes required for fatty acid transport and beta-oxidation including fadA, fadB, fadD, fadL and fadE. Activates transcription of at least three genes required for unsaturated fatty acid biosynthesis: fabA, fabB and iclR, the gene encoding the transcriptional regulator of the aceBAK operon encoding the glyoxylate shunt enzymes. (239 aa) |
| | narL | Response regulator in two-component regulatory system with NarX; This protein activates the expression of the nitrate reductase (narGHJI) and formate dehydrogenase-N (fdnGHI) operons and represses the transcription of the fumarate reductase (frdABCD) operon in response to a nitrate/nitrite induction signal transmitted by either the NarX or NarQ proteins. (216 aa) |
| | rssB | PcnB-degradosome interaction factor; Regulates the turnover of the sigma S factor (RpoS) by promoting its proteolysis in exponentially growing cells. Acts by binding and delivering RpoS to the ClpXP protease. RssB is not co- degraded with RpoS, but is released from the complex and can initiate a new cycle of RpoS recognition and degradation. In stationary phase, could also act as an anti-sigma factor and reduce the ability of RpoS to activate gene expression. Is also involved in the regulation of the mRNA polyadenylation pathway during stationary phase, probably by maintaining the asso [...] (337 aa) |
| | hns | Global DNA-binding transcriptional dual regulator H-NS; A DNA-binding protein implicated in transcriptional repression (silencing). Also involved in bacterial chromosome organization and compaction. H-NS binds tightly to AT-rich dsDNA and inhibits transcription. Binds upstream and downstream of initiating RNA polymerase, trapping it in a loop and preventing transcription. Binds to hundreds of sites, approximately half its binding sites are in non-coding DNA, which only accounts for about 10% of the genome. Many of these loci were horizontally transferred (HTG); this offers the selectiv [...] (137 aa) |
| | pspF | Psp operon transcriptional activator; Transcriptional activator for the phage shock protein (psp) operon (pspABCDE) and pspG gene. (325 aa) |
| | ycjW | Putative LACI-type transcriptional regulator; Protein involved in transcription repressor activity and transcription. (332 aa) |
| | tyrR | Aromatic amino acid biosynthesis and transport regulon transcriptional regulator; Involved in transcriptional regulation of aromatic amino acid biosynthesis and transport. Modulates the expression of at least 8 unlinked operons. Seven of these operons are regulated in response to changes in the concentration of the three aromatic amino acids (phenylalanine, tyrosine and tryptophan). These amino acids are suggested to act as co-effectors which bind to the TyrR protein to form an active regulatory protein. In most cases TyrR causes negative regulation, but positive effects on the tyrP ge [...] (513 aa) |
| | pgrR | Murein peptide degradation regulator; Regulates the expression of genes involved in peptidoglycan (PG) degradation. Could play a role in switch control between recycling and degradation of PG peptides. Negatively regulates the expression of the ycjY-ymjD-ymjC-mpaA operon by binding to the PgrR-box. In addition, other genes are predicted to be under the control of PgrR, including genes related to membrane formation and function. (299 aa) |
| | racR | Rac prophage; Repressor protein for rac prophage. (158 aa) |
| | paaX | Transcriptional repressor of phenylacetic acid degradation paa operon, phenylacetyl-CoA inducer; Negative regulator of the paaZ and paaABCDEFGHIJK catabolic operons. Binds the consensus sequence 5'-WWTRTGATTCGYGWT-3'. Binding of PaaX is specifically inhibited by phenylacetyl-coenzyme A (PA-CoA). (316 aa) |
| | ydcI | Putative transcriptional regulator LYSR-type; Protein involved in transcription activator activity, transcription repressor activity and transcription; Belongs to the LysR transcriptional regulatory family. (307 aa) |
| | ydcN | Putative DNA-binding transcriptional regulator; Regulates the expression of 12-16 transcription units involved in various steps of sulfur utilization. Represses expression of pfkB, fliZ, cysE, ydcO and its own expression. Activates expression of ypfN. Acts by binding to SutR boxes. (178 aa) |
| | mcbR | Colanic acid and biofilm gene transcriptional regulator, MqsR-controlled; Important for biofilm formation. Represses expression of McbA by binding to its promoter region, which prevents colanic acid overproduction and mucoidy. (221 aa) |
| | hipA | Serine/threonine-protein kinase toxin HipA; Toxic component of a type II toxin-antitoxin (TA) system, first identified by mutations that increase production of persister cells, a fraction of cells that are phenotypic variants not killed by antibiotics, which lead to multidrug tolerance. Persistence may be ultimately due to global remodeling of the persister cell's ribosomes. Phosphorylates Glu-tRNA-ligase (AC P04805, gltX, on 'Ser-239') in vivo. Phosphorylation of GltX prevents it from being charged, leading to an increase in uncharged tRNA(Glu). This induces amino acid starvation and [...] (440 aa) |
| | hipB | Antitoxin of HipAB toxin-antitoxin system; Antitoxin component of a type II toxin-antitoxin (TA) system. Neutralizes the toxic effect of cognate toxin HipA. Also neutralizes the toxic effect of non-cognate toxin YjjJ. Binds to operator sites with the consensus sequence 5-'TATCCN(8)GGATA-3' to repress the hipBA operon promoter ; binding of HipB(2) to DNA induces a 70 degree bend. This forces HipA dimerization, which blocks HipA's active site and thus its toxic action. May play a role in biofilm formation. (88 aa) |
| | marR | Transcriptional repressor of multiple antibiotic resistance; Repressor of the marRAB operon which is involved in the activation of both antibiotic resistance and oxidative stress genes. Binds to the marO operator/promoter site. (144 aa) |
| | marA | Multiple antibiotic resistance transcriptional regulator; May be a transcriptional activator of genes involved in the multiple antibiotic resistance (Mar) phenotype. It can also activate genes such as sodA, zwf and micF. (127 aa) |
| | cspI | Qin prophage; Cold shock-like protein. (70 aa) |
| | cspB | Qin prophage; cold shock protein. (71 aa) |
| | cspF | Qin prophage; cold shock protein. (70 aa) |
| | relE | Qin prophage; Toxic component of a type II toxin-antitoxin (TA) system. A sequence-specific, ribosome-dependent mRNA endoribonuclease that inhibits translation during amino acid starvation (the stringent response). In vitro acts by cleaving mRNA with high codon specificity in the ribosomal A site between positions 2 and 3. The stop codon UAG is cleaved at a fast rate while UAA and UGA are cleaved with intermediate and slow rates. In vitro mRNA cleavage can also occur in the ribosomal E site after peptide release from peptidyl- tRNA in the P site as well as on free 30S subunits. In vivo [...] (95 aa) |
| | relB | Antitoxin of the RelE-RelB toxin-antitoxin syste; Antitoxin component of a type II toxin-antitoxin (TA) system. Counteracts the effect of cognate toxin RelE via direct protein-protein interaction, preventing RelE from entering the ribosome A site and thus inhibiting its endoribonuclease activity. An autorepressor of relBE operon transcription. 2 RelB dimers bind to 2 operator sequences; DNA- binding and repression is stronger when complexed with toxin/corepressor RelE by conditional cooperativity. Increased transcription rate of relBE and activation of relE is consistent with a lower l [...] (79 aa) |
| | uidR | Transcriptional repressor; Repressor for the uidRABC (gusRABC) operon. (196 aa) |
| | malI | Transcriptional repressor of Mal regulon; Repressor for the malX and malY genes. Also regulates its own expression. Binds maltose as an inducer. (342 aa) |
| | cnu | Nucleoid-associated oriC-binding protein; Modifies the set of genes regulated by H-NS; Hha and Cnu (YdgT) increase the number of genes bound by H-NS/StpA and may also modulate the oligomerization of the H-NS/StpA-complex on DNA. The complex formed with H-NS binds to the specific 26-bp cnb site in the origin of replication oriC. Can complement, at least partially, the absence of the Hha protein in hha mutants. (71 aa) |
| | slyA | Global transcriptional regulator; Transcription regulator that can specifically activate or repress expression of target genes. Activates expression of genes such as molecular chaperones (groL, groS, dnaK, grpE, and cbpA), proteins involved in acid resistance (hdeA, hdeB, and gadA), the starvation lipoprotein slp, virulence protein hlyE/clyA. Represses expression of genes involved in the histidine biosynthetic pathway such as hisA, hisB, hisD, hisF and hisG. Required for the activation of virulence genes; Belongs to the SlyA family. (144 aa) |
| | nemR | Transcriptional repressor for the nemRA-gloA operon, quinone-, glyoxal-, and HOCl-activated; Involved in response to both electrophiles and reactive chlorine species (RCS). Represses the transcription of the nemRA-gloA operon by binding to the NemR box. May sense electrophiles, primarily quinones and glyoxals, as redox signals and regulate the redox state by modulating the expression of nemA and gloA. Also uses the oxidation status of HOCl-sensitive cysteine residues to respond to bleach and related RCS. Involved in response to methylglyoxal. (199 aa) |
| | purR | Transcriptional repressor, hypoxanthine-binding; Is the main repressor of the genes involved in the de novo synthesis of purine nucleotides, regulating purB, purC, purEK, purF, purHD, purL, purMN and guaBA expression. In addition, it participates in the regulation or coregulation of genes involved in de novo pyrimidine nucleotide biosynthesis, salvage and uptake (pyrC, pyrD, carAB and codBA), and of several genes encoding enzymes necessary for nucleotide and polyamine biosynthesis (prsA, glyA, gcvTHP, speA, glnB). Binds to a 16-bp palindromic sequence located within the promoter region [...] (341 aa) |
| | chbR | Repressor of chb operon for N,N'-diacetylchitobiose utilization; Dual-function repressor/activator of the chbBCARFG operon. In the absence of the inducing sugar chitobiose, together with NagC, represses the chbBCARFG operon for the uptake and metabolism of chitobiose. In association with Crp, and probably in the presence of chitobiose 6-phosphate, induces the transcription of the chbBCARFG operon. (280 aa) |
| | yeaM | Putative DNA-binding transcriptional regulator; Negatively regulates expression of the nimT operon and its own expression. Acts by binding to the nimR-nimT intergenic region. (273 aa) |
| | dmlR | Transcriptional activator of dmlA; Transcriptional regulator required for the aerobic growth on D-malate as the sole carbon source. Induces the expression of dmlA in response to D-malate or L- or meso-tartrate. Negatively regulates its own expression. (307 aa) |
| | cspC | Stress protein, member of the CspA-family; Cold shock protein; Protein involved in transcription activator activity, transcription and response to temperature stimulus. (69 aa) |
| | kdgR | KDG regulon transcriptional repressor; Transcriptional regulator of the kdgK gene for the kdg kinase and the kdgT gene for the kdg permease. (263 aa) |
| | fliZ | RpoS antagonist; During the post-exponential growth phase transiently interferes with RpoS (sigma S) activity without affecting expression of RpoS itself. It is probably not an anti-sigma factor as its overexpression is detrimental in rapidly growing cells where there is almost no sigma S factor. There is a strong overlap between Crl- activated genes and FliZ-down-regulated genes. FliZ acts as a timing device for expression of the genes for the adhesive curli fimbriae by indirectly decreasing expression of the curli regulator CsgD. (183 aa) |
| | rcsA | Transcriptional regulator of colanic acid capsular biosynthesis; Component of the Rcs signaling system, which controls transcription of numerous genes. Binds, with RcsB, to the RcsAB box to regulate expression of genes involved in colanic acid capsule synthesis. (207 aa) |
| | yedW | Response regulator family protein; Member of a two-component regulatory system HprR/HprS involved in response to hydrogen peroxide. Regulates the expression of at least 5 operons, cyoABCDE, hprRS, hiuH, cusRS and cusCFBA. Bifunctional regulator that acts as an activator and a repressor. (223 aa) |
| | nac | Nitrogen assimilation regulon transcriptional regulator; Transcriptional activator for the hut, put and ure operons and repressor for the gdh and gltB operons in response to nitrogen limitation. Negative regulator of its own expression (By similarity). (305 aa) |
| | yefM | Antitoxin of the YoeB-YefM toxin-antitoxin system; Antitoxin component of a type II toxin-antitoxin (TA) system. Antitoxin that counteracts the effect of the YoeB toxin. YefM binds to the promoter region of the yefM-yeoB operon to repress transcription, YeoB acts as a corepressor. (83 aa) |
| | yegW | Putative transcriptional regulator; Protein involved in transcription repressor activity and transcription. (248 aa) |
| | rcnR | Transcriptional repressor of rcnA; Repressor of rcnA expression. Acts by binding specifically to the rcnA promoter in the absence of nickel and cobalt. In the presence of one of these metals, it has a weaker affinity for rcnA promoter. Belongs to the FrmR/RcnR family. (90 aa) |
| | ada | Fused DNA-binding transcriptional dual regulator/O6-methylguanine-DNA methyltransferase; Involved in the adaptive response to alkylation damage in DNA caused by alkylating agents. Repairs O6-methylguanine (O6-MeG) and O4- methylthymine (O4-MeT) in DNA. Repairs the methylated nucleobase in DNA by stoichiometrically transferring the methyl group to a cysteine residue in the enzyme (Cys-321). Also specifically repairs the Sp diastereomer of DNA methylphosphotriester lesions by the same mechanism, although the methyl transfer occurs onto a different cysteine residue (Cys-38). Cannot demeth [...] (354 aa) |
| | rcsB | Response regulator in two-component regulatory system with RcsC and YojN; Component of the Rcs signaling system, which controls transcription of numerous genes. RcsB is the response regulator that binds to regulatory DNA regions. Can function both in an RcsA-dependent or RcsA-independent manner. The system regulates expression of numerous genes, including genes involved in colanic acid capsule synthesis, biofilm formation, cell division and outer membrane proteins synthesis. Also involved, with GadE, in control of glutamate-dependent acid resistance, and, with BglJ, in derepression of [...] (216 aa) |
| | rhmR | Putative DNA-binding transcriptional regulator for the rhm operon; Putative regulator; Protein involved in transcription and regulation of transcription, DNA-dependent. (260 aa) |
| | lrhA | Transcriptional repressor of flagellar, motility and chemotaxis genes; Not known, does not seem to act on the proton translocating NADH dehydrogenase genes (nuoA-N) which are part of the lrhA operon. (312 aa) |
| | murR | Repressor for murPQ, MurNAc 6-P inducible; Represses the expression of the murPQ operon involved in the uptake and degradation of N-acetylmuramic acid (MurNAc). Binds to two adjacent inverted repeats within the operator region. MurNAc 6- phosphate, the substrate of MurQ, is the specific inducer that weakens binding of MurR to the operator. Also represses its own transcription. (285 aa) |
| | hcaR | Hca operon transcriptional regulator; Transcriptional activator of the hca operon for 3- phenylpropionic acid catabolism. (296 aa) |
| | rseB | Anti-sigma E factor, binds RseA; Negatively modulates the activity of sigma-E (RpoE) by stabilizing RseA under non-stress conditions. Although not essential for association of sigma-E with Rsea it increases their affinity 2- to 3-fold. When bound to RseA it prevents proteolysis by DegS, which is probably relieved by lipopolysaccharide binding (LPS). Belongs to the RseB family. (318 aa) |
| | rseA | Anti-sigma factor; An anti-sigma factor for extracytoplasmic function (ECF) sigma factor sigma-E (RpoE). ECF sigma factors are held in an inactive form by an anti-sigma factor until released by regulated intramembrane proteolysis (RIP). RIP occurs when an extracytoplasmic signal triggers a concerted proteolytic cascade to transmit information and elicit cellular responses. The membrane-spanning regulatory substrate protein is first cut periplasmically (site-1 protease, S1P, DegS), then within the membrane itself (site-2 protease, S2P, RseP), while cytoplasmic proteases finish degrading [...] (216 aa) |
| | rpoE | RNA polymerase sigma E factor; Sigma factors are initiation factors that promote the attachment of RNA polymerase (RNAP) to specific initiation sites and are then released. Extracytoplasmic function (ECF) sigma-E controls the envelope stress response, responding to periplasmic protein stress, increased levels of periplasmic lipopolysaccharide (LPS) as well as heat shock and oxidative stress; it controls protein processing in the extracytoplasmic compartment. The 90 member regulon consists of the genes necessary for the synthesis and maintenance of both proteins and LPS of the outer me [...] (191 aa) |
| | csiR | Transcriptional repressor of csiD; Negatively regulates the expression of the glaH-lhgD-gabDTP operon in a temporal manner during entry into stationary phase or during the first few hours of carbon starvation. Thereby is involved in the regulation of a L-lysine degradation pathway that proceeds via cadaverine, glutarate and L-2- hydroxyglutarate. Binds to two primary and two secondary sites in the promoter region of the glaH operon with the consensus sequences TTGTN5TTTT and ATGTN5TTTT of the primary sites, each separated by six nucleotides. (220 aa) |
| | stpA | DNA binding protein, nucleoid-associated; A DNA-binding protein that acts in a fashion similar to H-NS protein upon overexpression, represses a number of genes including the cryptic blg operon, hns, papB and the proU locus. A subset of H-NS/StpA-regulated genes also require Hha for repression; Hha and Cnu (YdgT) increases the number of genes DNA bound by H-NS/StpA and may also modulate the oligomerization of the H-NS/StpA-complex. Repression can be inhibited by dominant-negative mutants of StpA or H-NS. (134 aa) |
| | mprA | Transcriptional repressor of microcin B17 synthesis and multidrug efflux; Negative regulator of the multidrug operon emrAB. (176 aa) |
| | alaS | alanyl-tRNA synthetase; Catalyzes the attachment of L-alanine to tRNA(Ala) in a two- step reaction: L-alanine is first activated by ATP to form Ala-AMP and then transferred to the acceptor end of tRNA(Ala). AlaRS also incorrectly activates the sterically smaller amino acid glycine as well as the sterically larger amino acid L-serine; generates 2-fold more mischarged Gly than Ser. These mischarged amino acids occur because the of inherent physicochemical limitations on discrimination between closely related amino acids (Ala, Gly and Ser) in the charging step. Attaches Ala to transfer-me [...] (876 aa) |
| | srlR | Sorbitol-inducible srl operon transcriptional repressor; Regulator for gut (srl), glucitol operon; Protein involved in carbohydrate catabolic process, transcription and regulation of transcription, DNA-dependent. (257 aa) |
| | ascG | Asc operon transcriptional repressor; Repressor of the asc operon. The cryptic operon is activated by the insertion of IS186 into the ascG gene. (336 aa) |
| | rpoS | RNA polymerase, sigma S (sigma 38) factor; Sigma factors are initiation factors that promote the attachment of RNA polymerase to specific initiation sites and are then released. This sigma factor is the master transcriptional regulator of the stationary phase and the general stress response. Controls, positively or negatively, the expression of several hundred genes, which are mainly involved in metabolism, transport, regulation and stress management. (330 aa) |
| | argP | HTH-type transcriptional regulator ArgP; Controls the transcription of genes involved in arginine and lysine metabolism. Activates transcription of several genes, including argO, lysP, lysC, asd, dapB, dapD, lysA, gdhA and argK. Acts by binding directly to their promoter or control region. ArgP dimer by itself is able to bind the argO promoter-operator region to form a binary complex, but the formation of a ternary complex with RNA polymerase is greatly stimulated only in presence of a coeffector. Both arginine and lysine are coeffectors at the argO promoter, but only arginine is compe [...] (297 aa) |
| | mqsR | GCU-specific mRNA interferase toxin of the MqsR-MqsA toxin-antitoxin system; Toxic component of a type II toxin-antitoxin (TA) system. Plays a significant role in the control of biofilm formation and induction of persister cells in the presence of antibiotics. An mRNA interferase which has been reported to be translation-independent. It has also been reported to be translation-dependent. Cleavage has been reported to occur on either side of G in the sequence GCU. Also reported to cleave after C in GC(A/U) sequences. There are only 14 genes in E.coli W3110 (and probably also MG1655) tha [...] (98 aa) |
| | ygiV | Transcriptional repressor for mcbR biofilm gene; Represses expression of mcbR. (160 aa) |
| | rpoD | RNA polymerase, sigma 70 (sigma D) factor; Sigma factors are initiation factors that promote the attachment of RNA polymerase to specific initiation sites and are then released. This sigma factor is the primary sigma factor during exponential growth. Preferentially transcribes genes associated with fast growth, such as ribosomal operons, other protein-synthesis related genes, rRNA- and tRNA-encoding genes and prfB. Belongs to the sigma-70 factor family. RpoD/SigA subfamily. (613 aa) |
| | yqjI | PadR family putative transcriptional regulator; Represses the expression of YqjH which is involved in iron homeostasis under excess nickel conditions. Also represses its own expression. (207 aa) |
| | ebgR | Transcriptional repressor; Repressor for beta galactosidase alpha and beta subunits (ebgA and ebgC). Binds lactose as an inducer. (327 aa) |
| | exuR | Hexuronate regulon transcriptional repressor; Repressor for the exu regulon that encode genes involved in hexuronate utilization. It regulates the ExuT, UxaCA and UxuRAB operons. Binds D-tagaturonate and D-fructuronate as inducers. (258 aa) |
| | prlF | Antitoxin of the SohA(PrlF)-YhaV toxin-antitoxin system; Antitoxin component of a type II toxin-antitoxin (TA) system. Labile antitoxin that binds to the YhaV toxin and neutralizes its ribonuclease activity. Also acts as a transcription factor. The YhaV/PrlF complex binds the prlF-yhaV operon, probably negatively regulating its expression. (111 aa) |
| | nanR | Sialic acid-inducible nan operon repressor; Transcriptional repressor that controls expression of the genes required for the catabolism of sialic acids. Represses expression of the nanATEK- yhcH, nanCMS and yjhBC operons. Acts by binding directly to the Nan box, a region of approximately 30 bp covering the promoter region. (263 aa) |
| | argR | L-arginine-responsive arginine metabolism regulon transcriptional regulator; Negatively controls the expression of the four operons of arginine biosynthesis in addition to the carAB operon. Predominantly interacts with A/T residues in ARG boxes. It also binds to a specific site in cer locus. Thus it is essential for cer-mediated site-specific recombination in ColE1. It is necessary for monomerization of the plasmid ColE1; Belongs to the ArgR family. (156 aa) |
| | fis | Global DNA-binding transcriptional dual regulator; Activates ribosomal RNA transcription, as well other genes. Plays a direct role in upstream activation of rRNA promoters. Binds to a recombinational enhancer sequence that is required to stimulate hin- mediated DNA inversion. Prevents initiation of DNA replication from oriC. Binds to hundreds of transcriptionally active and inactive AT- rich sites, approximately half its binding sites are in non-coding DNA, which only accounts for about 10% of the genome. Belongs to the transcriptional regulatory Fis family. (98 aa) |
| | acrS | acrAB operon transcriptional repressor; Potential regulator protein for the acrEF/envCD genes. (220 aa) |
| | rplD | 50S ribosomal subunit protein L4; One of the primary rRNA binding proteins, this protein initially binds near the 5'-end of the 23S rRNA. It is important during the early stages of 50S assembly. It makes multiple contacts with different domains of the 23S rRNA in the assembled 50S subunit and ribosome. Forms part of the polypeptide exit tunnel. Belongs to the universal ribosomal protein uL4 family. (201 aa) |
| | crp | cAMP-activated global transcription factor, mediator of catabolite repression; A global transcription regulator. Complexes with cyclic AMP (cAMP) which allosterically activates DNA binding (to consensus sequence 5'-AAATGTGATCTAGATCACATTT-3') to directly regulate the transcription of about 300 genes in about 200 operons and indirectly regulate the expression of about half the genome. There are 3 classes of CRP promoters; class I promoters have a single CRP-binding site upstream of the RNA polymerase (RNAP)-binding site, whereas in class II promoters the single CRP- and RNAP-binding site [...] (210 aa) |
| | frlR | Putative DNA-binding transcriptional regulator; May regulate the transcription of the frlABCDR operon, involved in the utilization of fructoselysine and psicoselysine. (243 aa) |
| | gntR | D-gluconate inducible gluconate regulon transcriptional repressor; Negative regulator for the gluconate utilization system GNT- I, the gntUKR operon. (331 aa) |
| | nikR | Transcriptional repressor, Ni-binding; Transcriptional repressor of the nikABCDE operon. Is active in the presence of excessive concentrations of intracellular nickel; Belongs to the transcriptional regulatory CopG/NikR family. (133 aa) |
| | cspA | RNA chaperone and antiterminator, cold-inducible; Binds to and stimulates the transcription of the CCAAT- containing, cold-shock-inducible promoters of the H-NS and GyrA proteins. Binds also to the inverted repeat 5'-ATTGG-3'. (70 aa) |
| | yiaJ | Transcriptional repressor for the yiaKLMNO-lyxK-sgbHUE operon; Negatively controls the transcription of the yiaKLMNOPQRS operon, which may be involved in the utilization of 2,3-diketo-L- gulonate. (282 aa) |
| | mtlR | Mannitol operon repressor; Involved in the repression of the expression of the mannitol mtlADR operon. Does not bind the operator/promoter regulatory region of this operon. Therefore, seems to belong to a new class of transcription factors in bacteria that may regulate gene expression indirectly, perhaps as a part of a larger transcriptional complex. (195 aa) |
| | lldR | Dual role activator/repressor for lldPRD operon; May be a regulatory protein for the LCT genes. (258 aa) |
| | yidP | Uncharacterized HTH-type transcriptional regulator YidP; Pseudogene, arbutin specific enzyme IIC component of PTS;enzyme; Transport of small molecules: Carbohydrates, organic acids, alcohols; PTS system, arbutin-like IIB component; PTS system, arbutin-like IIC component. (238 aa) |
| | asnC | Transcriptional activator of asnA; Activator of asnA transcription; autogenous regulator of its own transcription; and repressor of the expression of gidA at a post- transcriptional level. (152 aa) |
| | yihL | Putative transcriptional regulator; Protein involved in transcription repressor activity and transcription. (236 aa) |
| | yihW | Putative transcriptional regulator for sulphoquinovose utilization; Involved in the regulation of the sulfoquinovose operon. Represses the expression of the yihUTS operon and of the yihV and csqR genes. Binds DNA inside the spacer between the bidirectional transcription units comprising the yihUTS operon and the yihV gene, and upstream the csqR gene itself. (261 aa) |
| | cpxR | Response regulator in two-component regulatory system with CpxA; Response regulator member of the two-component regulatory system CpxA/CpxR which responds to envelope stress response by activating expression of downstream genes including cpxP, degP, dsbA and ppiA. Required for efficient binding of stationary phase cells to hydrophobic surfaces, part of the process of biofilm formation. Induced upon cell surface binding, subsequently induces genes it controls (cpxP, dsbA and spy, degP is only partially induced). Binds and activates transcription from the degP promoter ; binding is enhan [...] (232 aa) |
| | cytR | Anti-activator for CytR-CRP nucleoside utilization regulon; This protein negatively controls the transcription initiation of genes such as deoCABD, udp, and cdd encoding catabolizing enzymes and nupC, nupG, and tsx encoding transporting and pore-forming proteins. Binds cytidine and adenosine as effectors. (341 aa) |
| | metJ | Transcriptional repressor, S-adenosylmethionine-binding; This regulatory protein, when combined with SAM (S- adenosylmethionine) represses the expression of the methionine regulon and of enzymes involved in SAM synthesis. It is also autoregulated. (105 aa) |
| | fabR | Transcriptional repressor of fabA and fabB; Binds the promoter region of at least fabA and fabB, but probably not yqfA. Represses the transcription of fabA and fabB, involved in unsaturated fatty acid (UFA) biosynthesis. By controlling UFA production, FabR directly influences the physical properties of the membrane bilayer. (215 aa) |
| | rsd | Stationary phase protein, binds sigma 70 RNA polymerase subunit; Binds RpoD and negatively regulates RpoD-mediated transcription activation by preventing the interaction between the primary sigma factor RpoD with the catalytic core of the RNA polymerase and with promoter DNA. May be involved in replacement of the RNA polymerase sigma subunit from RpoD to RpoS during the transition from exponential growth to the stationary phase. Belongs to the Rsd/AlgQ family. (158 aa) |
| | iclR | Transcriptional repressor; Regulation of the glyoxylate bypass operon (aceBAK), which encodes isocitrate lyase, malate synthase as well as isocitrate dehydrogenase kinase/phosphorylase. Glyoxylate disrupts the interaction with the promoter by favoring the inactive dimeric form. Pyruvate enhances promoter binding by stabilizing the tetrameric form. (274 aa) |
| | lexA | Transcriptional repressor of SOS regulon; Represses a number of genes involved in the response to DNA damage (SOS response), including recA and lexA. Binds to the 16 bp palindromic sequence 5'-CTGTATATATATACAG-3'. In the presence of single- stranded DNA, RecA interacts with LexA causing an autocatalytic cleavage which disrupts the DNA-binding part of LexA, leading to derepression of the SOS regulon and eventually DNA repair. Implicated in hydroxy radical-mediated cell death induced by hydroxyurea treatment .The SOS response controls an apoptotic-like death (ALD) induced (in the absence [...] (202 aa) |
| | zur | Transcriptional repressor, Zn(II)-binding; Acts as a negative controlling element, employing Zn(2+) as a cofactor to bind the operator of the repressed genes (znuACB); Belongs to the Fur family. (171 aa) |
| | alsR | D-allose-inducible als operon transcriptional repressor; Regulatory protein involved in rpiB gene repression. Also involved in als operon repression. (296 aa) |
| | nsrR | Nitric oxide-sensitive repressor for NO regulon; Nitric oxide-sensitive repressor of genes involved in protecting the cell against nitrosative stress, such as ytfE, hmpA and ygbA. May require iron for activity. Does not regulates its own transcription. (141 aa) |
| | aidB | DNA alkylation damage repair protein; Part of the adaptive DNA-repair response to alkylating agents. Could prevent alkylation damage by protecting DNA and destroying alkylating agents that have yet to reach their DNA target. Binds to double-stranded DNA with a preference for a DNA region that includes its own promoter. Shows weak isovaleryl-CoA dehydrogenase activity in vitro. (541 aa) |
| | ulaR | Transcriptional repressor for the L-ascorbate utilization divergent operon; Represses ulaG and the ulaABCDEF operon. Two ulaR binding sites have been identified in each promoter. Full activity requires simultaneous interaction of UlaR with both divergent promoters and seems to be dependent on repressor-mediated DNA loop formation, which is helped by the action of integration host factor. (251 aa) |
| | treR | Trehalose 6-phosphate-inducible trehalose regulon transcriptional repressor; Repressor of the treBC operon. It is able to bind trehalose- 6-phosphate and trehalose. (315 aa) |
| | bdcR | Transcriptional repressor for divergent bdcA; Negatively regulates expression of bdcA. (197 aa) |
| | fecR | Anti-sigma transmembrane signal transducer for ferric citrate transport; Regulation of iron dicitrate transport. In the absence of citrate FecR inactivates fecI. FecR is probably a sensor that recognizes iron dicitrate in the periplasm. (317 aa) |
| | yjhI | Putative regulator; Protein involved in transcription repressor activity and transcription. (262 aa) |
| | trpR | Transcriptional repressor, tryptophan-binding; This protein is an aporepressor. When complexed with L- tryptophan it binds the operator region of the trp operon (5'- ACTAGT-'3') and prevents the initiation of transcription. The complex also regulates trp repressor biosynthesis by binding to its regulatory region. (108 aa) |
| | arcA | Response regulator in two-component regulatory system with ArcB or CpxA; Member of the two-component regulatory system ArcB/ArcA. Represses a wide variety of aerobic enzymes under anaerobic conditions. Controls the resistance of E.coli to dyes; required for expression of the alkaline phosphatase and sex factor F genes; It also may be involved in the osmoregulation of envelope proteins. When activated by ArcB, it negatively regulates the expression of genes of aerobic function. Activates the transcription of the plfB operon by binding to its promoter. (238 aa) |
| | dgoR | D-galactonate catabolism operon transcriptional repressor; Repressor for the dgoRKAT operon. Binds D-galactonate as an inducer. (229 aa) |
| | hdfR | flhDC operon transcriptional repressor; Negatively regulates the transcription of the flagellar master operon flhDC by binding to the upstream region of the operon. Belongs to the LysR transcriptional regulatory family. (279 aa) |
| | torI | Response regulator inhibitor for tor operon; Transcription inhibitory protein for the torCAD operon. Also acts as an excisionase and plays an essential role in the defective prophage CPS53 excision. (66 aa) |
| | yoeB | Toxin of the YoeB-YefM toxin-antitoxin system; Toxic component of a type II toxin-antitoxin (TA) system. Its mode of function is controversial; it has been proposed to be an mRNA interferase but also an inhibitor of translation initiation. When overproduced in wild-type cells, inhibits bacterial growth and translation by cleavage of mRNA molecules while it has a weak effect on colony forming ability. Overproduction of Lon protease specifically activates YoeB-dependent mRNA cleavage, leading to lethality. YefM binds to the promoter region of the yefM-yeoB operon to repress transcription [...] (84 aa) |
