This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Ferguson, G. P.
Right arrow Articles by Booth, I. R.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Ferguson, G. P.
Right arrow Articles by Booth, I. R.

 Previous Article  |  Next Article 

J. Bacteriol., Feb 1997, 1007-1012, Vol 179, No. 4
Copyright © 1997, American Society for Microbiology

Survival during exposure to the electrophilic reagent N-ethylmaleimide in Escherichia coli: role of KefB and KefC potassium channels

GP Ferguson, Y Nikolaev, D McLaggan, M Maclean and IR Booth
Department of Molecular and Cell Biology, Institute of Medical Sciences, University of Aberdeen, United Kingdom.

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. Activation of KefB and KefC aids the survival of cells exposed to high concentrations (> 100 microM) of NEM. High potassium concentrations reduce the protection afforded by activation of KefB and KefC, but the possession of these systems is still important under these conditions. The Kdp system, which confers sensitivity to the electrophile methylglyoxal, did not affect the survival of cells exposed to NEM. Survival is correlated with the reduction of the cytoplasmic pH upon activation of the channels. In particular, the kinetics of the intracellular pH (pHi) change are crucial to the retention of viability of cells exposed to NEM; slow acidification does not protect cells as effectively as rapid lowering of pHi. Cells treated with low levels of NEM (10 microM) recover faster if they activate KefB and KefC, and this correlates with changes in pHi. The pHi does not significantly alter the rate of NEM metabolism. The possible mechanisms by which protection against the electrophile is mediated are discussed.


This article has been cited by other articles:

  • Mojica, E.-R. E., Kim, S., Aga, D. S. (2008). Formation of N-Ethylmaleimide (NEM)-Glutathione Conjugate and N-Ethylmaleamic Acid Revealed by Mass Spectral Characterization of Intracellular and Extracellular Microbial Metabolites of NEM. Appl. Environ. Microbiol. 74: 323-326 [Abstract] [Full Text]  
  • Fujisawa, M., Ito, M., Krulwich, T. A. (2007). Three two-component transporters with channel-like properties have monovalent cation/proton antiport activity. Proc. Natl. Acad. Sci. USA 104: 13289-13294 [Abstract] [Full Text]  
  • Pittman, M. S., Robinson, H. C., Poole, R. K. (2005). A Bacterial Glutathione Transporter (Escherichia coli CydDC) Exports Reductant to the Periplasm. J. Biol. Chem. 280: 32254-32261 [Abstract] [Full Text]  
  • Bott, C. B., Love, N. G. (2004). Implicating the Glutathione-Gated Potassium Efflux System as a Cause of Electrophile-Induced Activated Sludge Deflocculation. Appl. Environ. Microbiol. 70: 5569-5578 [Abstract] [Full Text]  
  • Sze, H., Padmanaban, S., Cellier, F., Honys, D., Cheng, N.-H., Bock, K. W., Conejero, G., Li, X., Twell, D., Ward, J. M., Hirschi, K. D. (2004). Expression Patterns of a Novel AtCHX Gene Family Highlight Potential Roles in Osmotic Adjustment and K+ Homeostasis in Pollen Development. Plant Physiol. 136: 2532-2547 [Abstract] [Full Text]  
  • Sassetti, C. M., Rubin, E. J. (2003). Genetic requirements for mycobacterial survival during infection. Proc. Natl. Acad. Sci. USA 100: 12989-12994 [Abstract] [Full Text]  
  • Uozumi, N. (2001). Escherichia coli as an expression system for K+ transport systems from plants. Am. J. Physiol. Cell Physiol. 281: C733-C739 [Abstract] [Full Text]  
  • Evans, G. J., Ferguson, G. P., Booth, I. R., Vuilleumier, S. (2000). Growth inhibition of Escherichia coli by dichloromethane in cells expressing dichloromethane dehalogenase/glutathione S-transferase. Microbiology 146: 2967-2975 [Abstract] [Full Text]  
  • Saier, M. H. Jr. (2000). A Functional-Phylogenetic Classification System for Transmembrane Solute Transporters. Microbiol. Mol. Biol. Rev. 64: 354-411 [Abstract] [Full Text]  
  • McLaggan, D., Rufino, H., Jaspars, M., Booth, I. R. (2000). Glutathione-Dependent Conversion of N-Ethylmaleimide to the Maleamic Acid by Escherichia coli: an Intracellular Detoxification Process. Appl. Environ. Microbiol. 66: 1393-1399 [Abstract] [Full Text]  
  • Ness, L. S., Booth, I. R. (1999). Different Foci for the Regulation of the Activity of the KefB and KefC Glutathione-gated K+ Efflux Systems. J. Biol. Chem. 274: 9524-9530 [Abstract] [Full Text]  
  • Ferguson, G. P., Booth, I. R. (1998). Importance of Glutathione for Growth and Survival of Escherichia coli Cells: Detoxification of Methylglyoxal and Maintenance of Intracellular K+. J. Bacteriol. 180: 4314-4318 [Abstract] [Full Text]  
  • Ferguson, G. P., Creighton, R. I., Nikolaev, Y., Booth, I. R. (1998). 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. 180: 1030-1036 [Abstract] [Full Text]