Nitrogenase activity of pea bacteroids as affected by carbohydrates and ammonium chloride
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Regulation and efficiency of the nitrogen-fixing system of the rhizobium-pea symbiosis were investigated. Acetylene reduction of detached root nodules was measured with various substrates added. Succinate, fumarate and malate were most effective in stimulating nitrogenase activity; glucose, pyruvate and citrate were also active. Acetylene reducing activity of detached nodules was inhibited by the addition of NH4Cl, irrespective of the substrate present. Nitrogenase activity of isolated bacteroids was not influenced by NH4Cl.
Respiration of detached nodules was not significantly stimulated by the addition of substrates. Ammonium chloride did not influence respiration. With detached nodules and isolated bacteroids a consumption of about 16 g of carbohydrate per g of nitrogen fixed could be calculated. Detached nodules produced more hydrogen relative to the acetylene reduced than did isolated bacteroids and intact plants.
Results obtained indicate that the regulation of nitrogenase activity and the efficiency of substrate consumption depend on environmental conditions.
Key WordsAcetylene reduction Ammonium chloride Bacteroids Nitrogenase Pea Pisum sativum Respiration Rhizobium leguminosarum
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- 1.Antoniw, L. D. and Sprent, J. I. 1978 Primary metabolites ofPhaseolus vulgaris nodules. Phytochemistry17, 675–678.Google Scholar
- 6.Bethlenfalvay, G. J. and Phillips, D. A. 1977 Effect of light intensity on efficiency of carbon dioxide and nitrogen reduction inPisum sativum L. Plant Physiol.60, 868–871.Google Scholar
- 7.Bethlenfalvay, G. J., Abu-Shakra, S. S. and Phillips, D. A. 1978 Interdependence of nitrogen nutrition and photosynthesis inPisum sativum L. I. Effect of combined nitrogen on symbiotic fixation and photosynthesis. Plant Physiol.62, 127–130.Google Scholar
- 8.Brotonegoro, S. 1974 Nitrogen fixation and nitrogenase activity ofAzotobacter chroococcum. Ph.D. Thesis, Agricultural University, Wageningen, The Netherlands.Google Scholar
- 10.Dalton, H. and Postgate, J. R. 1969 Effect of oxygen on growth ofAzotobacter chroococcum in batch and continuous cultures. J. Gen. Microbiol.54, 463–473.Google Scholar
- 12.Houwaard, F. 1979 Effect of ammonium chloride and methionine sulfoximine on the acetylene reduction of detached root nodules of peas (Pisum sativum). Appl. Environ. Microbiol.37, 73–79.Google Scholar
- 16.Lambers, H. 1979 Energy metabolism in higer plants in different environments. Ph.D. Thesis, University of Groningen, Groningen, The Netherlands.Google Scholar
- 17.Lawrie, A. C. and Wheeler, C. T. 1975 Nitrogen fixation in the root nodules ofVicia faba L. in relation to the assimilation of carbon. II. The dark fixation of carbon dioxide. New Phytol.74, 437–445.Google Scholar
- 18.Mahon, J. D. 1977 Respiration and the energy requirement for nitrogen fixation in nodulated pea roots. Plant Physiol.60, 817–821.Google Scholar
- 19.Minchin, F. R. and Pate, J. S. 1973 The carbon balance of a legume and the functional economy of its root nodules. J. Exp. Bot.24, 259–271.Google Scholar
- 21.Phillips, D. A. 1974 Promotion of acetylene reduction byRhizobium-soybean associationsin vitro. Plant Physiol.54, 654–655.Google Scholar
- 22.Ruiz-Arguëso, T., Hanus, J. and Evans, H. J. 1978 Hydrogen production and uptake by pea nodules as affected by strains ofRhizobium leguminosarum. Arch. Microbiol.116, 113–118.Google Scholar
- 23.Ryle, G. J. A., Powell, C. E. and Gordon, A. J. 1979 The respiratory costs of nitrogen fixation in soyabean, cowpea, and white clover. I. Nitrogen fixation and the respiration of the nodulated root. J. Exp. Bot.30, 135–144.Google Scholar
- 24.Schubert, K. R. and Evans, H. J. 1976 Hydrogen evolution: a major factor affecting the efficiency of nitrogen fixation in nodulated symbionts. Proc. Natl. Acad. Sci. U.S.A.73, 1207–1211.Google Scholar
- 26.Shanmugam, K. T., O'Gara, F., Andersen, K. and Valentine, R. C. 1978 Biological nitrogen fixation. Annu. Rev. Plant. Physiol.29, 263–276.Google Scholar
- 27.Sprent, J. I. and Gallacher, A. 1976 Anaerobiosis in soybean root nodules under water stress. Soil Biol. Biochem.8, 317–320.Google Scholar
- 28.Stovall, I. and Cole, M. 1978 Organic acid metabolism by isolatedRhizobium japonicum bacteroids. Plant Physiol.61, 787–790.Google Scholar
- 30.Streeter, J. G. and Bosler, M. E. 1976 Carbohydrates in soybean nodules: identification of compounds and possible relationships to nitrogen fixation. Plant Sci. Lett.7, 321–329.Google Scholar
- 31.Tuzimura, K. and Meguro, H. 1960 Respiration substrate ofRhizobium in the nodules. J. Biochem.47, 391–397.Google Scholar
- 32.Houwaard, F. 1979 Effect of combined nitrogen on symbiotic nitrogen fixation in pea plants. Ph. D. Thesis, Agric. Univ. Wageningen, The Netherlands.Google Scholar