Gene Symbol: kefB
Description: potassium:proton antiporter
Alias: ECK3338, JW3313, trkB
Species: Escherichia coli str. K-12 substr. MG1655

Top Publications

  1. Ferguson G, Tötemeyer S, Maclean M, Booth I. Methylglyoxal production in bacteria: suicide or survival?. Arch Microbiol. 1998;170:209-18 pubmed the primary route of methylglyoxal detoxification, and the glutathione conjugates formed can activate the KefB and KefC potassium channels...
  2. Epstein W, Kim B. Potassium transport loci in Escherichia coli K-12. J Bacteriol. 1971;108:639-44 pubmed
    ..The trk loci are widely scattered over the E. coli chromosome; none of them is very near any other trk locus or near the kdp genes. ..
  3. Ferguson G, McLaggan D, Booth I. Potassium channel activation by glutathione-S-conjugates in Escherichia coli: protection against methylglyoxal is mediated by cytoplasmic acidification. Mol Microbiol. 1995;17:1025-33 pubmed
    Escherichia coli possesses two glutathione-gated potassium channels, KefB and KefC, that are activated by glutathione-S-conjugates formed with methylglyoxal...
  4. Ness L, Booth I. Different foci for the regulation of the activity of the KefB and KefC glutathione-gated K+ efflux systems. J Biol Chem. 1999;274:9524-30 pubmed
    b>KefB and KefC are glutathione-gated K+ efflux systems in Escherichia coli, and the proteins exhibit strong similarity at the level of both primary sequence and domain organization...
  5. Fujisawa M, Ito M, Krulwich T. Three two-component transporters with channel-like properties have monovalent cation/proton antiport activity. Proc Natl Acad Sci U S A. 2007;104:13289-94 pubmed
    ..They are peripheral membrane proteins that are encoded in operons with the respective transporter proteins, KefB and KefC, and are required for optimal efflux activity...
  6. Ferguson G, Battista J, Lee A, Booth I. Protection of the DNA during the exposure of Escherichia coli cells to a toxic metabolite: the role of the KefB and KefC potassium channels. Mol Microbiol. 2000;35:113-22 pubmed
    ..The activity of the KefB and KefC potassium channels protects E. coli cells against methylglyoxal and limits the amount of DNA damage...
  7. Miller S, Ness L, Wood C, Fox B, Booth I. Identification of an ancillary protein, YabF, required for activity of the KefC glutathione-gated potassium efflux system in Escherichia coli. J Bacteriol. 2000;182:6536-40 pubmed
    ..Deletion of yabF reduces KefC activity 10-fold, and supply of YabF in trans restores activity. IS2 and IS10R insertions in yabF can be isolated as suppressors of KefC activity consequent upon the V427A and D264A KefC mutations. ..
  8. Rhoads D, Waters F, Epstein W. Cation transport in Escherichia coli. VIII. Potassium transport mutants. J Gen Physiol. 1976;67:325-41 pubmed
    ..All transport systems are able to extrude Na during K uptake. The measurements of cell Na suggest that growing cells of E. coli have very low concentrations of Na, considerably lower than indicated by earlier studies. ..
  9. Ferguson G, Creighton R, Nikolaev Y, Booth I. Importance of RpoS and Dps in survival of exposure of both exponential- and stationary-phase Escherichia coli cells to the electrophile N-ethylmaleimide. J Bacteriol. 1998;180:1030-6 pubmed
    ..Stationary-phase E. coli cells were more resistant to NEM than exponential-phase cells. The KefB and KefC systems were found to play an important role in protecting both exponential- and stationary-phase cells ..

More Information


  1. Trchounian A. Ion exchange in facultative anaerobes: does a proton-potassium pump exist in anaerobic Escherichia Coli?. Anaerobe. 1997;3:355-71 pubmed
  2. Booth I, Epstein W, Giffard P, Rowland G. Roles of the trkB and trkC gene products of Escherichia coli in K+ transport. Biochimie. 1985;67:83-9 pubmed
    Mutations at the trkB and trkC loci of Escherichia coli produce an abnormal efflux of K+. The mutations are partially dominant in diploids and revert frequently by what appears to be intragenic suppression to the null state...
  3. Bakker E, Booth I, Dinnbier U, Epstein W, Gajewska A. Evidence for multiple K+ export systems in Escherichia coli. J Bacteriol. 1987;169:3743-9 pubmed
    The role of the K+ transport systems encoded by the kefB (formerly trkB) and kefC (formerly trkC) genes of Escherichia coli in K+ efflux has been investigated...
  4. Booth I, Ferguson G, Miller S, Li C, Gunasekera B, Kinghorn S. Bacterial production of methylglyoxal: a survival strategy or death by misadventure?. Biochem Soc Trans. 2003;31:1406-8 pubmed
    ..The KefB and KefC glutathione-gated K(+) efflux systems are integrated with the activity of the glyoxalase system to ..
  5. Ferguson G, Munro A, Douglas R, McLaggan D, Booth I. Activation of potassium channels during metabolite detoxification in Escherichia coli. Mol Microbiol. 1993;9:1297-303 pubmed
    ..g. Escherichia coli, such glutathione adducts activate one, or both, of a pair of potassium efflux systems KefB and KefC. These systems share many of the properties of cation-translocating channels in eukaryotes...
  6. Elmore M, Lamb A, Ritchie G, Douglas R, Munro A, Gajewska A, et al. Activation of potassium efflux from Escherichia coli by glutathione metabolites. Mol Microbiol. 1990;4:405-12 pubmed
    ..critical factor is the formation of specific glutathione metabolites that activate transport systems encoded by the kefB and kefC gene products...
  7. Ferguson G, Nikolaev Y, McLaggan D, MacLean M, Booth I. Survival during exposure to the electrophilic reagent N-ethylmaleimide in Escherichia coli: role of KefB and KefC potassium channels. J Bacteriol. 1997;179:1007-12 pubmed
    The role of the KefB and KefC potassium efflux systems in protecting Escherichia coli cells against the toxic effects of the electrophile N-ethylmaleimide has been investigated...