Biomics

Biological fixation of nitrogen, associated with the enzymatic transfer of atmospheric gaseous nitrogen to mineral nitrogen in the form of ammonia, is an important process for maintaining soil fertility and life on Earth. The complex of nif-genes (from nitrogen fixation) that code for the synthesis and regulation of the enzyme nitrogenase is present only in prokaryotic organisms. Nitrogen-fixing microorganisms have a wide range of habitats, from free-living forms in the soil and to symbiotic in the nodules on the roots of leguminous plants. Therefore, these microorganisms have formed complex regulatory networks that are controlled by numerous environmental signals. In this paper, some mechanisms of regulation of the bacterial nitrogen fixation process were considered.

nitrogen fixation, free-living nitrogen fixers, nitrogenase, nitrogen fixation, nif-genes, sym-genes

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