1887

Abstract

The marine bacterium , containing 470 mM-K and 70 mM-Na inside its cells, was able to regulate the cytoplasmic pH (pH) in the narrow range 7.6–7.8 over the external pH (pH) range 6.0–9.0 in the presence of 400 mM-Na and 10 mM-K. In the absence of external K, however, pH was regulated only at alkaline pH values above 7.6. When the cells were incubated in the presence of unusually high K (400 mM) and 4 mM Na, the pH was regulated only at acidic pH values below 7.6. These results could be explained by postulating a K/H antiporter as the regulator of pH over the pH range 6.0–9.0. When Na-loaded/K-depleted cells were incubated in 400 mM-Na in the absence of K, an inside acidic ΔpH was generated at pH values above 7.0. After addition of diethanolamine the inside acidic ΔpH collapsed transiently and then returned to the original value concomitant with the extrusion of Na, suggesting the participation of a Na/H antiporter for the generation of an inside acidic ΔpH. In the presence of 400 mM-K, at least 5 mM-Na was required to support cell growth at pH below 7.5. An increase in Na concentration allowed the cells to grow at a more alkaline pH. Furthermore, cells containing more Na inside could more easily adapt to grow at alkaline pH. These results indicated the importance of Na in acidification of the cell interior via a Na/H antiporter in order to support cell growth at alkaline pH under conditions where the activity of a K/H antiporter is marginal.

Loading

Article metrics loading...

/content/journal/micro/10.1099/00221287-138-6-1271
1992-06-01
2021-07-30
Loading full text...

Full text loading...

/deliver/fulltext/micro/138/6/mic-138-6-1271.html?itemId=/content/journal/micro/10.1099/00221287-138-6-1271&mimeType=html&fmt=ahah

References

  1. Bassilana M., Damiano E., Leblanc G. 1984a; Relationships between the Na+/H+ antiport activity and the components of the electrochemical proton gradient in Escherichia coli membrane vesicles. Biochemistry 23:1015–1022
    [Google Scholar]
  2. Bassilana M., Damiano E., Leblanc G. 1984b; Kinetic properties of Na+/H+ antiport in Escherichia coli membrane vesicles : effects of imposed electrical potential, proton gradient, and internal pH. Biochemistry 23:5288–5294
    [Google Scholar]
  3. Booth I. R. 1985; Regulation of cytoplasmic pH in bacteria. Microbiological Reviews 49:359–378
    [Google Scholar]
  4. Booth I. R., Epstein W., Giffard P. M., Rowland G. C. 1985; Roles of the trkB and trkC gene products of Escherichia coli in potassium transport. Biochimie 67:83–90
    [Google Scholar]
  5. Brey R. N., Rosen B. P., Sorensen E. N. 1980; Cation/proton antiport in Escherichia coli. . Journal of Biological Chemistry 255:39
    [Google Scholar]
  6. Castle A. M., Macnab R. M., Shulman R. G. 1986a; Measurement of intracellular sodium concentration and sodium transport in Escherichia coli by 23Na nuclear magnetic resonance. Journal of Biological Chemistry 261:3288–3294
    [Google Scholar]
  7. Castle A. M., Macnab R. M., Shulman R. G. 1986; Coupling between the sodium and proton gradients in respiring Escherichia coli cells measured by 23Na and 31P nuclear magnetic resonance. Journal of Biological Chemistry 261:7797–7806
    [Google Scholar]
  8. Douglas R. M., Roberts J. Δ., Munro A. W., Richie G. Y., Lamb A. J., Booth I. R. 1991; The distribution of homologues of the Escherichia coli KefC K+-efflux system in other bacterial species. Journal of General Microbiology 137:1999–2005
    [Google Scholar]
  9. Garcia M. L., Guffanti A. A., Krulwich T. A. 1983; Characterization of the Na+/H+ antiporter of alkalophilic bacilli in vivo: Ai/r-dependent 22Na+ efflux from whole cells. Journal of Bacteriology 156:1151–1157
    [Google Scholar]
  10. Goldberg E. B., Arbel T., Chen J., Karpel R., Mackie G. Δ., Schuldiner S., Padan E. 1987; Characterization of a Na+/H+ antiporter gene of Escherichia coli. . Proceedings of the National Academy of Sciences of the United States of America 84:2615–2619
    [Google Scholar]
  11. Ishikawa T., Hama H., Tsuda M., Tsuchiya T. 1987; Isolation and properties of a mutant of Escherichia coli possessing defective Na+/H+ antiporter. Journal of Biological Chemistry 262:7443–7446
    [Google Scholar]
  12. Ivey D. M., Guffanti Δ. Δ., Bossewitch J. S., Padan E., Krulwich T. A. 1991; Molecular cloning and sequencing of a gene from alkaliphilic Bacillus firmus OF4 that functionally complements an Escherichia coli strain carrying a deletion in the nhaA Na+/H+ antiporter gene. Journal of Biological Chemistry 266:23483–23489
    [Google Scholar]
  13. Kakinuma Y., Igarashi K. 1988; Active potassium extrusion regulated by intracellular pH in Streptococcus faecalis . Journal of Biological Chemistry 263:14166–14170
    [Google Scholar]
  14. Karpel R., Olami Y., Taglicht D., Schuldiner S., Padan E. 1988; Sequencing of the gene ant which affects the Na+/H+ antiporter activity in Escherichia coli . Journal of Biological Chemistry 263:10408–10414
    [Google Scholar]
  15. Kroll R. G., Booth I. R. 1983; The relationship between intracellular pH, the pH gradient and potassium transport in Escherichia coli. . Biochemical Journal 216:709–716
    [Google Scholar]
  16. Kumar S., Nicholas D. J. D. 1984; Na+ and K+ transport in Nitrosomonas europaea and Nitrosobactor agilis . Biochimica et Biophysica Acta 765:268–274
    [Google Scholar]
  17. McMorrow I., Shuman H. Δ., Sze D., Wilson D. M., Wilson T. H. 1989; Sodium/proton antiport is required for growth of Escherichia coli at alkaline pH. Biochimica et Biophysica Acta 981:21–26
    [Google Scholar]
  18. Mandel Κ. G., Guffanti A. A., Krulwich T. A. 1980; Monovalent cation/proton antiporters in membrane vesicles from Bacillus alcalophilus . Journal of Biological Chemistry 255:7391–7396
    [Google Scholar]
  19. Munro Δ., Ritchie G. Y., Lamb A. J., Douglas R. M., Booth I. R. 1991; The cloning and DNA sequence of the gene for the glutathione-regulated potassium efflux system KefC of Escherichia coli. . Molecular Microbiology 5:607–616
    [Google Scholar]
  20. Nakamura T., Hsu C.-M., Rosen B. P. 1986; Cation/proton antiport systems in Escherichia coli: solubilization and reconstitution of ΔpH-driven sodium/proton and calcium/proton antiporters. Journal of Biological Chemistry 261:678–683
    [Google Scholar]
  21. Nakamura T., Tokuda H., Unemoto T. 1982; Effects of pH and monovalent cations on the potassium ion exit from the marine bacterium, Vibrio alginolyticus, and the manipulation of cellular cation contents. Biochimica et Biophysica Acta 692:386–396
    [Google Scholar]
  22. Nakamura T., Tokuda H., Unemoto T. 1984; K+/H+ antiporter functions as a regulator of cytoplasmic pH in a marine bacterium, Vibrio alginolyticus . Biochimica et Biophysica Acta 776:330–336
    [Google Scholar]
  23. Niiya S., Yamasaki K., Wilson T. H., Tsuchiya T. 1982; Altered cation coupling to melibiose transport in mutants of Escherichia coli. . Journal of Biological Chemistry 257:8902–8906
    [Google Scholar]
  24. Padan E., Makler N., Taglicht D., Karpel R., Schuldiner S. 1989; Deletion of ant in Escherichia coli reveals its function in adaptation to high salinity and an alternative Na+/H+ antiporter system(s). Journal of Biological Chemistry 256:20297–20302
    [Google Scholar]
  25. Slonczewski J. L., Rosen B. P., Alger J. R., Macnab R. M. 1981; pH homeostasis in Escherichia coli: measurement by nuclear magnetic resonance of methylphosphate and phosphate. Proceeding of the National Academy of Sciences of the United States of America 78:6271–6275
    [Google Scholar]
  26. Taglicht D., Padan E., Schuldiner S. 1991; Overproduction and purification of a functional Na+/H+ antiporter coded by nhaA (ant) from Escherichia coli. . Journal of Biological Chemistry 266:11289–11294
    [Google Scholar]
  27. Tokuda H., Unemoto T. 1984; Na+ is translocated at NADH :quinone oxidoreductase segment in the respiratory chain of Vibrio alginolyticus . Journal of Biological Chemistry 259:7785–7790
    [Google Scholar]
  28. Tokuda H., Nakamura T., Unemoto T. 1981; Potassium ion is a requirement for the generation of pH-dependent membrane potential and ΔpH by the marine bacterium Vibrio alginolyticus . Biochemistry 20:4198–4203
    [Google Scholar]
  29. Tromballa H.-W. 1987; Base uptake, K+ transport and intracellular pH regulation by the green alga Chlorella fusca . Biochimica et Biophysica Acta 904:216–226
    [Google Scholar]
http://instance.metastore.ingenta.com/content/journal/micro/10.1099/00221287-138-6-1271
Loading
/content/journal/micro/10.1099/00221287-138-6-1271
Loading

Data & Media loading...

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error