1887

Abstract

Because the DCCD (dicyclohexylcarbodiimide)-sensitive, F-ATPase-mediated, futile ATP hydrolysis of non-growing JB1 cells was not affected by sodium or potassium, ATP hydrolysis appeared to be dependent only upon the rate of proton flux across the cell membrane. However, available estimates of bacterial proton conductance were too low to account for the rate of ATP turnover observed in . . When de-energized cells were subjected to large pH gradients (275 units, or −170 mV), internal pH declined at a rate of 015 pH units s. Based on an estimated cellular buffering capacity of 200 nmol H (mg protein) per pH unit, H flux across the cell membrane (at −170 mV) was 108 mmol (g protein) h. When potassium-loaded cells were treated with valinomycin in low-potassium buffers, initial K efflux generated membrane potentials in close agreement with values predicted by the Nernst equation. These artificial membrane potentials drove H uptake, and H influx was counterbalanced by a further loss of cellular K. Flame photometry indicated that the rate of K loss was 215 (±26) mmol K (g protein) h at −170 mV, but the potassium-sensitive fluorescent compound CD222 indicated that this rate was only 110 (±44) mmol K (g protein) h. As pH gradients or membrane potentials were reduced, the rate of H flux declined in a non-ohmic fashion, and all rates were <25 mmol (g protein) h at a driving force of −80 mV. Previous estimates of bacterial proton flux were based on low and unphysiological protonmotive forces, and the assumption that H influx rate would be ohmic. Rates of H influx into . cells [as high as 9×10 mol H (cm membrane) s] were similar to rates reported for respiring mitochondria, but were at least 20-fold greater than any rate previously reported in lactic acid bacteria.

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2000-03-01
2024-04-23
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References

  1. Bakker E. P., Harold F. M. 1980; Energy coupling to potassium transport in Streptococcus faecalis. J Biol Chem 255:433–440
    [Google Scholar]
  2. Bender G. R., Sutton S. V. W., Marquis R. E. 1986; Acid tolerance, proton permeabilites, and membrane ATPases of oral streptococci. Infect Immun 53:331–338
    [Google Scholar]
  3. Bond D. R., Russell J. B. 1996; A role for fructose 1,6-diphosphate in the ATPase-mediated energy-spilling reaction of Streptococcus bovis. Appl Environ Microbiol 62:2095–2099
    [Google Scholar]
  4. Bond D. R., Russell J. B. 1998; Relationship between intracellular phosphate, proton motive force, and rate of nongrowth energy dissapation (energy spilling) in Streptococcus bovis JB1. Appl Environ Microbiol 64:976–981
    [Google Scholar]
  5. Brand M. D., Chien L.-F., Ainscow E. K., Rolfe D. F. S., Porter R. K. 1994; The causes and functions of mitochondrial proton leak. Biochim Biophys Acta 1187:132–139 [CrossRef]
    [Google Scholar]
  6. Brookes P. S., Rolfe D. F. S., Brand M. D. 1997; The proton permeability of liposomes made from mitochondrial inner membrane phosopholipids: comparison with isolated mitochondria. J Membr Biol 155:167–174 [CrossRef]
    [Google Scholar]
  7. Casadio R., Di Bernardo S., Fariselli P., Melandri A. 1995; Characterization of 9-aminoacridine interaction with chromatophore membranes and modelling of the probe response to artificially induced transmembrane pH gradients. Biochim Biophys Acta 1237:23–30 [CrossRef]
    [Google Scholar]
  8. Cramer W. A., Knaff D. B. 1991 Energy Transduction in Biological Membranes. A Textbook of Bioenergetics p. 103 New York: Springer;
    [Google Scholar]
  9. Deamer D. W., Nichols J. W. 1989; Proton flux in model and biological membranes. J Membr Biol 107:91–103 [CrossRef]
    [Google Scholar]
  10. Fordyce A. M., Crow L., Thomas T. D. 1984; Regulation of product formation during glucose or lactose limitation in nongrowing cells of Streptococcus lactis. Appl Environ Microbiol 483:332–337
    [Google Scholar]
  11. Harold F. M., Baarda J. R. 1969; Inhibition of membrane-bound adenosine triphosphatase and of cation transport in Streptococcus faecalis by N,N′-dicyclohexylcarbodiimide. J Biol Chem 244:2261–2268
    [Google Scholar]
  12. Harold F. M., Papineau P. 1972; Cation transport and electrogenesis by Streptococcus faecalis. I. The membrane potential. J Membr Biol 8:27–44 [CrossRef]
    [Google Scholar]
  13. Hirata H., Ohno K., Sone N., Kagawa Y., Hamamoto T. 1986; Direct measurement of the electrogenicity of the H+-ATPase from thermophilic bacterium PS3 reconstituted in planar phospholipid bilayers. J Biol Chem 261:9839–9843
    [Google Scholar]
  14. Krishnamoorthy G., Hinkle P. C. 1984; Non-ohmic proton conductance of mitochondria and liposomes. Biochemistry 23:1640–1645 [CrossRef]
    [Google Scholar]
  15. Lolkema J. S., Helligwerf K. J., Konings W. N. 1982; The effect of ‘probe binding’ on the quantitative determination of the proton-motive force in bacteria. Biochim Biophys Acta 1681:85–94
    [Google Scholar]
  16. Maloney P. C. 1977; Obligatory coupling between proton entry and the synthesis of adenosine 5′-triphosphate in Streptococcus lactis. J Bacteriol 132:564–575
    [Google Scholar]
  17. Maloney P. C. 1979; Membrane H+ conductance of Streptococcus lactis. J Bacteriol 140:197–205
    [Google Scholar]
  18. Maloney P. C. 1987 In Escherichia coli and Salmonella typhimurium: Cellular and Molecular Biology vol. 1 pp. 223–225Edited by Neidart F. C.others Washington, DC: American Society for Microbiology;
    [Google Scholar]
  19. Maloney P. C., Hansen F. C. 1982; Stoichiometry of proton movements coupled to ATP synthesis driven by a pH gradient in Streptococcus lactis. J Membr Biol 66:63–75 [CrossRef]
    [Google Scholar]
  20. Molenaar D., Abee T., Konings W. N. 1991; Continuous measurement of the cytoplasmic pH in Lactococcus lactis with a fluorescent pH indicator. Biochim Biophys Acta 115:75–83
    [Google Scholar]
  21. Molenaar D., Bolhuis H., Abee T., Poolman B., Konings W. N. 1992; The efflux of a fluorescent probe is catalyzed by an ATP-driven extrusion system in Lactococcus lactis. J Bacteriol 174:3118–3124
    [Google Scholar]
  22. Mulder M. M., Teixeira de Mattos M. J., Postma P. W., van Dam K. 1986; Energetic consequences of multiple K+ uptake systems in Escherichia coli. Biochim Biophys Acta 851:223–228 [CrossRef]
    [Google Scholar]
  23. Neijssel O. M., Teixeira de Mattos M. J. 1994; The energetics of bacterial growth: a reassessment. Mol Microbiol 13:179–182 [CrossRef]
    [Google Scholar]
  24. Otto R. 1984; Uncoupling of growth and acid production in Streptococcus cremoris. Arch Microbiol 140:225–230 [CrossRef]
    [Google Scholar]
  25. Rius N., Lorén J.-G. 1998; Buffering capacity and membrane H+ conductance of neutrophilic and alkalophilic gram-positive bacteria. Appl Environ Microbiol 64:1344–1349
    [Google Scholar]
  26. Rius N., Solé M., Francia A., Lorén J.-G. 1994; Buffering capacity and membrane H+ conductance of lactic acid bacteria. FEMS Microbiol Lett 120:291–296 [CrossRef]
    [Google Scholar]
  27. Rosenberger R. F., Elsden S. R. 1960; The yields of Streptococcus faecalis grown in continuous culture. J Gen Microbiol 22:726–739 [CrossRef]
    [Google Scholar]
  28. Russell J. B., Cook G. M. 1995; Energetics of bacterial growth: balance of anabolic and catabolic reactions. Microbiol Rev 59:48–62
    [Google Scholar]
  29. Russell J. B., Robinson P. H. 1984; Compositions and characteristics of strains of Streptococcus bovis. J Dairy Sci 67:1525–1531 [CrossRef]
    [Google Scholar]
  30. Russell J. B., Strobel H. J. 1990; ATPase-dependent energy spilling by the ruminal bacterium Streptococcus bovis. Arch Microbiol 153:378–383 [CrossRef]
    [Google Scholar]
  31. Russell J. B., Strobel H. J., Driessen A. J. M., Konings W. N. 1988; Sodium-dependent transport of neutral amino acids by cells and membrane vesicles of Streptococus bovis, a ruminal bacterium. J Bacteriol 170:3531–3536
    [Google Scholar]
  32. Strobel H. J., Russell J. B. 1989; Non-proton-motive-force-dependent sodium efflux from the ruminal bacterium Streptococcus bovis: bound versus free pools. Appl Environ Microbiol 55:2664–2668
    [Google Scholar]
  33. Tempest D. W., Neijssel O. M. 1984; The status of YATP and maintenance energy as biologically interpretable phenomena. Annu Rev Microbiol 38:459–486 [CrossRef]
    [Google Scholar]
  34. Taylor M. A., Jackson J. B. 1987; Adaptive changes in membrane conductance in response to changes in specific growth rate in continuous cultures of phototrophic bacteria under conditions of energy sufficiency. Biochim Biophys Acta 891:242–255 [CrossRef]
    [Google Scholar]
  35. Van Walraven H. S., Heinrich S., Schwartz O., Rumberg B. 1996; The H+/ATP coupling ratio from thiol-modulated chloroplasts and two cyanobacterial strains is four. FEBS Lett 379:309–313 [CrossRef]
    [Google Scholar]
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