Abstract
Soybean (Glycine max L. cv Williams) seeds were sown in pots containing a 1:1 perlite-vermiculite mixture and grown under greenhouse conditions. Nodules were initiated with a nitrate reductase expressing strain of Rhizobium japonicum, USDA 110, or with nitrate reductase nonexpressing mutants (NR− 108, NR− 303) derived from USDA 110. Nodules initiated with either type of strain were normal in appearance and demonstrated nitrogenase activity (acetylene reduction). The in vivo nitrate reductase activity of N2-grown nodules initiated with nitrate reductase-negative mutant strains was less than 10% of the activity shown by nodules initiated with the wild-type strain. Regardless of the bacterial strain used for inoculation, the nodule cytosol and the cell-free extracts of the leaves contained both nitrate reductase and nitrite reductase activities. The wild-type bacteroids contained nitrate reductase but not nitrite reductase activity while the bacteroids of strains NR− 108 and NR− 303 contained neither nitrate reductase nor nitrite reductase activities.
Addition of 20 millimolar KNO3 to bacteroids of the wild-type strain caused a decrease in nitrogenase activity by more than 50%, but the nitrate reductase-negative strains were insensitive to nitrate. The nitrogenase activity of detached nodules initiated with the nitrate reductase-negative mutant strains was less affected by the KNO3 treatment as compared to the wild-type strain; however, the results were less conclusive than those obtained with the isolated bacteroids.
The addition of either KNO3 or KNO2 to detached nodules (wild type) suspended in a semisolid agar nutrient medium caused an inhibition of nitrogenase activity of 50% and 65% as compared to the minus N controls, and provided direct evidence for a localized effect of nitrate and nitrite at the nodule level. Addition of 0.1 millimolar sucrose stimulated nitrogenase activity in the presence or absence of nitrate or nitrite. The sucrose treatment also helped to decrease the level of nitrite accumulated within the nodules.
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Selected References
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- Bradford M. M. A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding. Anal Biochem. 1976 May 7;72:248–254. doi: 10.1016/0003-2697(76)90527-3. [DOI] [PubMed] [Google Scholar]
- Chen P. C., Phillips D. A. Induction of Root Nodule Senescence by Combined Nitrogen in Pisum sativum L. Plant Physiol. 1977 Mar;59(3):440–442. doi: 10.1104/pp.59.3.440. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Finn G. A., Brun W. A. Effect of Atmospheric CO(2) Enrichment on Growth, Nonstructural Carbohydrate Content, and Root Nodule Activity in Soybean. Plant Physiol. 1982 Feb;69(2):327–331. doi: 10.1104/pp.69.2.327. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Franco A. A., Pereira J. C., Neyra C. A. Seasonal Patterns of Nitrate Reductase and Nitrogenase Activities in Phaseolus vulgaris L. Plant Physiol. 1979 Mar;63(3):421–424. doi: 10.1104/pp.63.3.421. [DOI] [PMC free article] [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]
- Harper J. E. Canopy and Seasonal Profiles of Nitrate Reductase in Soybeans (Glycine max L. Merr.). Plant Physiol. 1972 Feb;49(2):146–154. doi: 10.1104/pp.49.2.146. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Kennedy I. R., Rigaud J., Trinchant J. C. Nitrate reductase from bacteroides of Rhizobium japonicum: enzyme characteristics and possible interaction with nitrogen fixation. Biochim Biophys Acta. 1975 Jul 27;397(1):24–35. doi: 10.1016/0005-2744(75)90175-8. [DOI] [PubMed] [Google Scholar]
- Kuykendall L. D., Elkan G. H. Rhizobium japonicum derivatives differing in nitrogen-fixing efficiency and carbohydrate utilization. Appl Environ Microbiol. 1976 Oct;32(4):511–519. doi: 10.1128/aem.32.4.511-519.1976. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Manhart J. R., Wong P. P. Nitrate Effect on Nitrogen Fixation (Acetylene Reduction): ACTIVITIES OF LEGUME ROOT NODULES INDUCED BY RHIZOBIA WITH VARIED NITRATE REDUCTASE ACTIVITIES. Plant Physiol. 1980 Mar;65(3):502–505. doi: 10.1104/pp.65.3.502. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Manhart J. R., Wong P. P. Nitrate reductase activities of rhizobia and the correlation between nitrate reduction and nitrogen fixation. Can J Microbiol. 1979 Oct;25(10):1169–1174. doi: 10.1139/m79-181. [DOI] [PubMed] [Google Scholar]
- Neyra C. A., Hageman R. H. Pathway for Nitrate Assimilation in Corn (Zea mays L.) Leaves: Cellular Distribution of Enzymes and Energy Sources for Nitrate Reduction. Plant Physiol. 1978 Oct;62(4):618–621. doi: 10.1104/pp.62.4.618. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Neyra C. A., Van Berkum P. Nitrate reduction nitrogenase activity in Spirillum lipoferum1. Can J Microbiol. 1977 Mar;23(3):306–310. doi: 10.1139/m77-045. [DOI] [PubMed] [Google Scholar]
- Pagan J. D., Scowcroft W. R., Dudman W. F., Gibson A. H. Nitrogen fixation in nitrate reductase-deficient mutants of cultured rhizobia. J Bacteriol. 1977 Feb;129(2):718–723. doi: 10.1128/jb.129.2.718-723.1977. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Quebedeaux B., Havelka U. D., Livak K. L., Hardy R. W. Effect of Altered pO(2) in the Aerial Part of Soybean on Symbiotic N(2) Fixation. Plant Physiol. 1975 Dec;56(6):761–764. doi: 10.1104/pp.56.6.761. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Rigaud J., Puppo A. Effect of nitrite upon leghemoglobin and interaction with nitrogen fixation. Biochim Biophys Acta. 1977 May 26;497(3):702–706. doi: 10.1016/0304-4165(77)90291-4. [DOI] [PubMed] [Google Scholar]
- Streeter J. G. Synthesis and accumulation of nitrite in soybean nodules supplied with nitrate. Plant Physiol. 1982 Jun;69(6):1429–1434. doi: 10.1104/pp.69.6.1429. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Wong P. P. Nitrate and Carbohydrate Effects on Nodulation and Nitrogen Fixation (Acetylene Reduction) Activity of Lentil (Lens esculenta Moench). Plant Physiol. 1980 Jul;66(1):78–81. doi: 10.1104/pp.66.1.78. [DOI] [PMC free article] [PubMed] [Google Scholar]
- de Vasconcelos L., Miller L., Neyra C. A. Free-living and symbiotic characteristics of chlorate resistant mutants of Rhizobium. Can J Microbiol. 1980 Mar;26(3):338–342. doi: 10.1139/m80-055. [DOI] [PubMed] [Google Scholar]