منابع مشابه
Streptomyces thermoautotrophicus does not fix nitrogen.
Streptomyces thermoautotrophicus UBT1 has been described as a moderately thermophilic chemolithoautotroph with a novel nitrogenase enzyme that is oxygen-insensitive. We have cultured the UBT1 strain, and have isolated two new strains (H1 and P1-2) of very similar phenotypic and genetic characters. These strains show minimal growth on ammonium-free media, and fail to incorporate isotopically lab...
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A new study asserts that a late evolutionary leap in cyanobacterial nitrogen fixation terminated a long history of nitrogen-limited primary production in the ocean--and contributed to a dramatic increase in biospheric oxygen coincident with the rise of animals.
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Why do rhizobia expend resources on fixing N(2) for the benefit of their host plant, when they could use those resources for their own reproduction? We present a series of theoretical models which counter the hypotheses that N(2) fixation is favoured because it (i) increases the exudation of useful resources to related rhizobia in the nearby soil, or (ii) increases plant growth and therefore th...
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Stable strains of mutants of Azotobacter that do not fix nitrogen are difficult to obtain by traditional procedures (Karlsson and Barker, 1948; Lindstrom, 1948). Stumbo and Gainey (1938) demonstrated that culturing Azotobacter on a high nitrate medium resulted in strains that failed to fix nitrogen even after continued transfer in the absence of fixed nitrogen. However, since these strains were...
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ژورنال
عنوان ژورنال: Nature Geoscience
سال: 2012
ISSN: 1752-0894,1752-0908
DOI: 10.1038/ngeo1605