Abstract
Recent results on the regulation of nitrogen fixation and C4-dicarboxylate transport genes in Rhizobium meliloti are reviewed, nif gene expression is activated by the nifA gene product in conjunction with the ntrA sigma factor. Activation of the nifA gene does not require ntrC product but occurs in response to low oxygen tension. NifA protein activity is also sensitve to oxygen, dct regulatory gene products share homology to nitrogen regulatory gene products and to NifA, and NtrA is required for dct expression. The significance of the pattern of domain conservation found between the dct, ntr, and nif regulatory proteins is discussed.
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© 1988 ECSC, EEC, EAEC, Brussels and Luxembourg
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Ronson, C.W. (1988). Regulation of Nitrogen Fixation in the Rhizobium Meliloti Alfalfa Symbiosis. In: O’Gara, F., Manian, S., Drevon, J.J. (eds) Physiological Limitations and the Genetic Improvement of Symbiotic Nitrogen Fixation. Advances in Agricultural Biotechnology, vol 23. Springer, Dordrecht. https://doi.org/10.1007/978-94-009-1401-8_17
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DOI: https://doi.org/10.1007/978-94-009-1401-8_17
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