Abstract
Hydrogenase activity of root nodules in the symbiotic association between Pisum sativum L. and Rhizobium leguminosarum was determined by incubating unexcised nodules with tritiated H2 and measuring tissue HTO. Hydrogenase activity saturated at 0.50 millimolar H2 and was not inhibited by the presence of 0.10 atmosphere C2H2, which prevented H2 evolution from nitrogenase. Total H2 production from nitogenase was estimated as net H2 evolution in air plus H2 exchange in 0.10 atmosphere C2H2. Although such an estimate of nitrogenase function may not be quantitatively exact, due to uncertain relationships between H2 exchange and H2 uptake activity of hydrogenase, differences observed in H2 exchange under various conditions represent an indication of changes in hydrogenase activity. Hydrogenase activity was lower in associations grown under higher photosynthetic photon flux densities and decreased relative to total H2 production by nitrogenase. Total H2 production and hydrogenase activity were maximum 28 days after planting. Thereafter, hydrogenase activity and H2 production declined, but the potential proportion of nitrogenase-produced H2 recovered by the uptake hydrogenase system increased. Of five R. leguminosarum strains tested two possessed hydrogenase activity. Strains which had the potential to reassimilate H2 had significantly higher rates of N2 reduction than those which did not exhibit hydrogenase activity.
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- Anand S. R., Krasna A. I. Catalysis of the H2-HTO exchange by hydrogenase. A new assay for hydrogenase. Biochemistry. 1965 Dec;4(12):2747–2753. doi: 10.1021/bi00888a027. [DOI] [PubMed] [Google Scholar]
- Bethlenfalvay G. J., Abu-Shakra S. S., Phillips D. A. Interdependence of Nitrogen Nutrition and Photosynthesis in Pisum sativum L: I. Effect of Combined Nitrogen on Symbiotic Nitrogen Fixation and Photosynthesis. Plant Physiol. 1978 Jul;62(1):127–130. doi: 10.1104/pp.62.1.127. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Bethlenfalvay G. J., Abu-Shakra S. S., Phillips D. A. Interdependence of Nitrogen Nutrition and Photosynthesis in Pisum sativum L: II. Host Plant Response to Nitrogen Fixation by Rhizobium Strains. Plant Physiol. 1978 Jul;62(1):131–133. doi: 10.1104/pp.62.1.131. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Bethlenfalvay G. J., Phillips D. A. Effect of Light Intensity on Efficiency of Carbon Dioxide and Nitrogen Reduction in Pisum sativum L. Plant Physiol. 1977 Dec;60(6):868–871. doi: 10.1104/pp.60.6.868. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Bethlenfalvay G. J., Phillips D. A. Ontogenetic Interactions between Photosynthesis and Symbiotic Nitrogen Fixation in Legumes. Plant Physiol. 1977 Sep;60(3):419–421. doi: 10.1104/pp.60.3.419. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Dixon R. O. Hydrogenase in legume root nodule bacteroids: occurrence and properties. Arch Mikrobiol. 1972;85(3):193–201. doi: 10.1007/BF00408844. [DOI] [PubMed] [Google Scholar]
- Dixon R. O. Hydrogenase in pea root nodule bacterioids. Arch Mikrobiol. 1968;62(3):272–283. doi: 10.1007/BF00413898. [DOI] [PubMed] [Google Scholar]
- GINGRAS G., GOLDSBY R. A., CALVIN M. Carbon dioxide metabolism in hydrogen-adapted Scenedesmus. Arch Biochem Biophys. 1963 Feb;100:178–184. [PubMed] [Google Scholar]
- Hardy R. W., Holsten R. D., Jackson E. K., Burns R. C. The acetylene-ethylene assay for n(2) fixation: laboratory and field evaluation. Plant Physiol. 1968 Aug;43(8):1185–1207. doi: 10.1104/pp.43.8.1185. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Lim S. T. Determination of Hydrogenase in Free-living Cultures of Rhizobium japonicum and Energy Efficiency of Soybean Nodules. Plant Physiol. 1978 Oct;62(4):609–611. doi: 10.1104/pp.62.4.609. [DOI] [PMC free article] [PubMed] [Google Scholar]
- McCrae R. E., Hanus J., Evans H. J. Properties of the hydrogenase system in Rhizobium japonicum bacteroids. Biochem Biophys Res Commun. 1978 Jan 30;80(2):384–390. doi: 10.1016/0006-291x(78)90688-5. [DOI] [PubMed] [Google Scholar]
- Schubert K. R., Evans H. J. Hydrogen evolution: A major factor affecting the efficiency of nitrogen fixation in nodulated symbionts. Proc Natl Acad Sci U S A. 1976 Apr;73(4):1207–1211. doi: 10.1073/pnas.73.4.1207. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Schubert K. R., Jennings N. T., Evans H. J. Hydrogen Reactions of Nodulated Leguminous Plants: II. Effects on Dry Matter Accumulation and Nitrogen Fixation. Plant Physiol. 1978 Mar;61(3):398–401. doi: 10.1104/pp.61.3.398. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Smith L. A., Hill S., Yates M. G. Inhibition by acetylene of conventional hydrogenase in nitrogen-fixing bacteria. Nature. 1976 Jul 15;262(5565):209–210. doi: 10.1038/262209a0. [DOI] [PubMed] [Google Scholar]