Skip to main content

Table 1 Proposed biological roles of TFTRs of Salmonella and Escherichia. TFTRs present in all Gram-negative species tested are denoted as core**, while those not present in all species but present in all Escherichia and Salmonella are denoted as core*. The carriage of the remaining TFTRs found in Salmonella and Escherichia are listed (%, italicised for Salmonella). This data is combined with biological role as documented in literature. Known targets and ligands are included and targets known to be activated, not repressed, by the TFTR are in bold. A biological role was assigned from the literature if experimental evidence was provided (e.g. binding assays to show TFTR binding to promoter)

From: TetR-family transcription factors in Gram-negative bacteria: conservation, variation and implications for efflux-mediated antimicrobial resistance

TFTR Core/Accessory (%) Pathway Gene(s) or process regulated (organism) Ligands References
AcrR Core** Multidrug efflux (RND) Multidrug efflux (ABC) Multidrug efflux (MFS) Motility acrAB (Enterobacteriales) flhDC Rhodamine 6 g Proflavin Ethidium bromide Ciprofloxacin [19]
[20]
[21]
EnvR Core** Multidrug efflux (RND) Multidrug efflux (RND) acrAB (Enterobacteriales) acrEF (Enterobacteriales) No data available [9]
NemR Core** Bleach survival nemAB Choline [22]
SlmA Core* Cell division Chitin catabolism FtsZ ring formation(Enterobacteriales) chb operon (V. cholera) Target DNA sequences FtsZ protein [23]
[24]
[25]
YbiH Core* Multidrug efflux (ABC) Membrane permeability ybhGFSR (E. coli) rhlE(E. coli) Chloramphenicol Cephalosporin [26]
BetI Accessory (67%) Glycine betaine synthesis betT (Enterobacteriales) betIBA (Enterobacteriales) Choline [27]
EefR Accessory (47%) Multidrug efflux (RND) eefABC (Enterobacter spp., K. pneumoniae) No data available [28]
[29]
FabR Core Accessory (93%) Fatty acid biosynthesis fabAB (Enterobacteriales) Unsaturated thioester [30]
RamR Core Efflux regulation ramA (Enterobacteriales) Bile Berberine Ethidium bromide Dequalinium Crystal violet Rhodamine 6 g [31]
[32]
[33]
RutR Core Accessory (93%) Pyrimidine utilisation Purine degradation Glutamine supply PH homeostasis rutABCDEFG (E. coli) carAB (E. coli) gadAXW (E. coli) gadIBC (E. coli) gly-hyi-glxR-ybbVW-allB-ybbY-glxK (E. coli) Uracil Thymine [34]
[11]
[35]
TetR Accessory (40%) Accessory (20%) Multidrug efflux (ABC) tetAB (Enterobacteriales) Tetracycline [36]
UidR Accessory (67%) Catalysis of beta-glucuronidase uidA (E. coli) No data available [37]
U1 Core No data available No data available No data available  
YbjK/ RcdA Accessory (93%) Accessory (80%) Biofilm formation Stress response csgD (E. coli) appY, sxy, ycgF, fimB (E. coli) No data available [38]
YcfQ/ comR Accessory (80%) Core Copper transport comC (E. coli) Copper [39]
YftA Accessory (80%) No data available No data available No data available  
YjdC Accessory (67%) Core Copper tolerance cadABC (E. coli) No data available [40]
YjgJ/ bdcR Accessory (60%) Accessory (93%) Biofilm dispersal bdcA (E. coli) No data available [41]