Results 311 to 320 of about 332,407 (363)
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Science, 1959
Incorporation of N 15 into the fixed nitrogen fraction of natural lake waters has been studied for the purpose of estimating rates of primary nitrogen fixation. Experiments in Pymatuning Reservoir, Pennsylvania, in Lake Mendota, Wisconsin, and in two lakes in Alaska indicate that fixation occurs at measurable ...
Vera A. Dugdale +3 more
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Incorporation of N 15 into the fixed nitrogen fraction of natural lake waters has been studied for the purpose of estimating rates of primary nitrogen fixation. Experiments in Pymatuning Reservoir, Pennsylvania, in Lake Mendota, Wisconsin, and in two lakes in Alaska indicate that fixation occurs at measurable ...
Vera A. Dugdale +3 more
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Nitrogen fixation in cyanobacteria
2008Cyanobacteria are oxygenic photosynthetic bacteria that are widespread in marine, freshwater and terrestrial environments, and many of them are capable of fixing atmospheric nitrogen. However, ironically, nitrogenase, the enzyme that is responsible for the reduction of N2, is extremely sensitive to O2. Therefore, oxygenic photosynthesis and N2 fixation
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Journal of Applied Bacteriology, 1974
Summary. The acetylene reduction technique was used for a 3‐year period to monitor potential nitrogen fixation by aerobic heterotrophic bacteria in the sea 2 miles offshore in Cardigan Bay. Samples from depths down to 15 m were membrane‐filtered and the residues incubated aerobically or anaerobically in acetylene‐containing gas mixtures in sealed ...
Muriel E. Rhodes, D. D. Wynn-Williams
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Summary. The acetylene reduction technique was used for a 3‐year period to monitor potential nitrogen fixation by aerobic heterotrophic bacteria in the sea 2 miles offshore in Cardigan Bay. Samples from depths down to 15 m were membrane‐filtered and the residues incubated aerobically or anaerobically in acetylene‐containing gas mixtures in sealed ...
Muriel E. Rhodes, D. D. Wynn-Williams
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Annual Review of Nutrition, 1993
Biological nitrogen fixation (BNF) is the process of the reduction of dinitrogen from the air to ammonia carried out by a large number of species of free-living and symbiotic microbes called diazotrophs. BNF presents an inexpensive and environmentally sound, sustainable approach to crop production and constitutes one of the most important Plant Growth ...
Gary P. Roberts, Robert H. Burris
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Biological nitrogen fixation (BNF) is the process of the reduction of dinitrogen from the air to ammonia carried out by a large number of species of free-living and symbiotic microbes called diazotrophs. BNF presents an inexpensive and environmentally sound, sustainable approach to crop production and constitutes one of the most important Plant Growth ...
Gary P. Roberts, Robert H. Burris
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1995
Publisher Summary The conversion of the inert nitrogen molecule into combined nitrogen that can be utilized as a mineral nutrient is brought about either by reduction to ammonia or oxidation to nitrate. This conversion, also referred to as fixation, is highly energy consuming. This is the main focus of this chapter.
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Publisher Summary The conversion of the inert nitrogen molecule into combined nitrogen that can be utilized as a mineral nutrient is brought about either by reduction to ammonia or oxidation to nitrate. This conversion, also referred to as fixation, is highly energy consuming. This is the main focus of this chapter.
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Journal of Theoretical Biology, 1962
Abstract A theory of N 2 -fixation is developed, based on a consideration of the energy changes involved, in which N 2 is incorporated into an organic molecule. This leads to an explanation of hydrogenase activity and the effect of O 2 in aerobic N 2 -fixers, the absence of inorganic intermediates and the role of organic acids.
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Abstract A theory of N 2 -fixation is developed, based on a consideration of the energy changes involved, in which N 2 is incorporated into an organic molecule. This leads to an explanation of hydrogenase activity and the effect of O 2 in aerobic N 2 -fixers, the absence of inorganic intermediates and the role of organic acids.
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The Pathways of Nitrogen Fixation
1972Publisher Summary Biological nitrogen fixation is the enzymic reduction of atmospheric nitrogen to ammonia. Along with the scientific interest of nitrogen fixation as a fundamental biochemical reaction, it is also of great ecological and agricultural importance because it is the most important source of the metabolizable nitrogen needed by all living
Raymond C. Valentine, John R. Benemann
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Enzymology of nitrogen fixation
Trends in Biochemical Sciences, 1984Abstract Progress made during the last eight years with respect to the nature and function of the Fe/S clusters present in nitrogenase seems to be impressive. However recent developments may change the picture completely and lead to further research into the molecular mechanism of action of nitrogenase.
Haaker, H., Veeger, C.
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