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Archives of Microbiology

, Volume 155, Issue 1, pp 82–88 | Cite as

Energetics of syntrophic ethanol oxidation in defined chemostat cocultures

1. Energy requirement for H2 production and H2 oxidation
  • H. -J. Seitz
  • B. Schink
  • N. Pfennig
  • R. Conrad
Original Papers

Abstract

The ethanol-oxidizing, proton-reducing Pelobacter acetylenicus was grown in chemostat cocultures with either Acetobacterium woodii, Methanobacterium bryantii, or Desulfovibrio desulfuricans. Stable steady state conditions with tightly coupled growth were reached at various dilution rates between 0.02 and 0.14 h-1. Both ethanol and H2 steady state concentrations increased with growth rate and were lower in cocultures with the sulfate reducer < methanogen < homoacetogen. Due to the higher affinity for H2, D. desulfuricans outcompeted M. bryantii, and this one A. woodii when inoculated in cocultures with P. acetylenicus. Cocultures with A. woodii had lower H2 steady state concentrations when bicarbonate reduction was replaced by the energetically more favourable caffeate reduction. Similarly, cocultures with D. desulfuricans had lower H2 concentrations with nitrate than with sulfate as electron acceptor. The Gibbs free energy (ΔG) available to the H2-producing P. acetylenicus was independent of growth rate and the H2-utilizing partner, whereas the ΔG available to the latter increased with growth rate and the energy yielding potential of the H2 oxidation reaction. The “critical” Gibbs free energy (ΔGc), i.e. the minimum energy required for H2 production and H2 oxidation, was-5.5 to-8.0 kJ mol-1 H2 for P. acetylenicus,-5.1 to-6.3 kJ mol-1 H2 for A. woodii,-7.5 to-9.1 kJ mol-1 H2 for M. bryantii, and-10.3 to-12.3 kJ mol-1 H2 for D. desulfuricans. Obviously, the potentially available energy was used more efficiently by homoacetogens > methanogens > sulfate reducers.

Key words

Homoacetogenesis Methanogenesis Sulfate reduction Caffeate reduction Nitrate reduction Interspecies H2 transfer Affinity H2 threshold “Critical” Gibbs free energy 

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References

  1. Ahring BK, Westermann P (1987) Kinetics of butyrate, acetate, and hydrogen metabolism in a thermophilic, anaerobic, butyrate-degrading triculture. Appl Environ Microbiol 53:434–439Google Scholar
  2. Archer DB, Powell GE (1975) Dependence of the specific growth rate of methanogenic mutualistic cocultures on the methanogen. Arch Microbiol 141:133–137Google Scholar
  3. Bache R, Pfennig N (1981) Selective isolation of Acetobacterium woodii on methoxylated aromatic acids and determination of growth yields. Arch Microbiol 130:255–261Google Scholar
  4. Bryant MP (1979) Microbial methane production — theoretical aspects. J Anim Sci 48:193–201Google Scholar
  5. Buschhorn H, Dürre P, Gottschalk G (1989) Production and utilization of ethanol by the homoacetogen Acetobacterium woodii. Appl Environ Microbiol 55: 1835–1840Google Scholar
  6. Conrad R (1989) Control of methane production in terrestrial ecosystems. In: Andrease MO, Schimel DS (eds) Exchange of trace gases between terrestrial ecosystems and the atmosphere. Dahlem Konferenzen. John Wiley, Chichester, pp 39–58Google Scholar
  7. Conrad R, Schink B, Phelps TJ (1986) Thermodynamics of H2-consuming and H2-producing metabolic reactions in diverse methanogenic environments under in situ conditions. FEMS Microbiol Ecol 38:353–360Google Scholar
  8. Cord-Ruwisch R, Seitz HJ, Conrad R (1988) The capacity of hydrogenotrophic anaerobic bacteria to compete for traces of hydrogen depends on the redox potential of the terminal electron acceptor. Arch Microbiol 149:350–357Google Scholar
  9. Cypionka H (1986) Sulfide-controlled continuous culture of sulfate-reducing bacteria. J Microbiol Methods 5:1–9Google Scholar
  10. Dolfing J (1988) Acetogenesis. In: Zehnder AJB (ed) Biology of anaerobic microorganisms. John Wiley, New York, pp 427–468Google Scholar
  11. Dwyer DF, Weeg-Aerssens E, Shelton DR, Tiedje JM (1988) Bioenergetic conditions of butyrate metabolism by a syntrophic, anaerobic bacterium in coculture with hydrogen-oxidizing methanogenic and sulfidogenic bacteria. Appl Environ Microbiol 54:1354–1359Google Scholar
  12. Fardeau ML, Belaich JP (1986) Energetics of the growth of Methanococcus thermolithotrophicus. Arch Microbiol 144:381–385Google Scholar
  13. Grbic-Galic D (1985) Fermentative and oxidative transformation of ferulate by facultatively anaerobic bacteria isolated from sewage sludge. Appl Environ Microbiol 50:1052–1057Google Scholar
  14. Hansen B, Bokranz M, Schönheit P, Kröger A (1988) ATP formation coupled to caffeate reduction by H2 in Acetobacterium woodii NZva16. Arch Microbiol 150:447–451Google Scholar
  15. Kreikenbohm R, Bohl E (1986) A mathematical model of syntrophic cocultures in the chemostat. FEMS Microbiol Ecol 38:131–140Google Scholar
  16. Powell GE (1984) Equalisation of specific growth rates for syntrophic associations in batch culture. J Chem Technol Biotechnol 34B:97–100Google Scholar
  17. Powell GE (1985) Stable coexistence of syntrophic associations in continuous culture. J Chem Technol Biotechnol 35B:46–50Google Scholar
  18. Schink B, Pfennig N (1982) Fermentation of trihydroxybenzenes by Pelobacter acidigallici gen. nov., sp. nov., a new strictly anaerobic, non-sporeforming bacterium. Arch Microbiol 133:195–201Google Scholar
  19. Schönheit P, Moll J, Thauer RK (1980) Growth parameters (Ks, μmax, Ys) of Methanobacterium thermoautotrophicum. Arch Microbiol 127:59–65Google Scholar
  20. Seitz HJ, Schink B, Conrad R (1988) Thermodynamics of hydrogen metabolism in methanogenic cocultures degrading ethanol or lactate. FEMS Microbiol Lett 55:119–124Google Scholar
  21. Seitz HJ, Schink B, Pfennig N, Conrad R (1990) Energetics of syntrophic ethanol oxidation in defined chemostat cocultures. 2. Energy sharing in biomass production. Arch Microbiol 155Google Scholar
  22. Stumm W, Morgan JJ (1981) Aquatic chemistry. An introduction emphasizing chemical equilibria in natural waters. John Wiley, New YorkGoogle Scholar
  23. Szewzyk R, Pfennig N (1990) Competition for ethanol between sulfate-reducing and fermenting bacteria. Arch Microbiol 153:470–477Google Scholar
  24. Tatton MJ, Archer DB, Powell GE, Parker ML (1989) Methanogenesis from ethanol by defined mixed continuous cultures. Appl Environ Microbiol 55:440–445Google Scholar
  25. Thauer RK, Jungermann K, Decker K (1977) Energy conservation in chemotrophic anaerobic bacteria. Bacteriol Rev 41:100–180Google Scholar
  26. Thiele JH, Zeikus JG (1988) Control of interspecies electron flow during anaerobic digestion: significance of formate transfer versus hydrogen transfer during syntrophic methanogenesis in flocs. Appl Environ Microbiol 54:20–29Google Scholar
  27. Traore AS, Fardeau ML, Hatchikian CE, LeGall J, Belaich JP (1983) Energetics of growth of a defined mixed culture of Desulfovibrio vulgaris and Methanosarcina barkeri: Interspecies hydrogen transfer in batch and continuous cultures. Appl Environ Microbiol 46:1152–1156Google Scholar
  28. Widdel F, Pfennig N (1981) Studies on dissimilatory sulfate-reducing bacteria that decompose fatty acids. I. Isolation of new sulfate-reducing bacteria enriched with acetate from saline environments. Description of Desulfobacter postgatei gen. nov., sp. nov. Arch Microbiol 129:395–400Google Scholar
  29. Wolin MJ (1974) Metabolic interactions among intestinal microorganisms. Am J Clin Nutr 27:1320–1328Google Scholar
  30. Zehnder AJB (1978) Ecology of methane formation. In: Mitchell R (ed) Water pollution microbiology, vol 2. John Wiley, London pp 349–376Google Scholar

Copyright information

© Springer-Verlag 1990

Authors and Affiliations

  • H. -J. Seitz
    • 1
  • B. Schink
    • 2
  • N. Pfennig
    • 1
  • R. Conrad
    • 1
  1. 1.Fakultät für BiologieUniversität KonstanzKonstanzFederal Republic of Germany
  2. 2.Lehrstuhl Mikrobiologie IUniversität TübingenTübingenFederal Republic of Germany

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