Biological Nitrogen Fixation: From Rhizobia to Synthetic Approaches

Nitrogen has been known to be an essential macronutrient which significantly participates in the metabolic processes of plants, but it often represents the limiting factor responsible for arresting agricultural productivity, mainly due to the poor bioavailability of the nutrient within most soil textures. Biological nitrogen fixation (BNF), represents the process catalyzed by the widespread and heterogeneous class of prokaryotic bacterial microbes, which represents an environment friendly alternative to the energy-intensive processes of chemical synthesis presently utilized for the purpose of nitrogen fixation. Through the action of the enzyme complex known as nitrogenase, these microbes have the ability to convert the gaseous atmospheric dinitrogen (N2) to the ammonia, (NH3), which represents the assimilable and plant-usable form of the nutrient required for plant growth and productive development. In this writing, the evolution, the molecular mechanisms underlying the resultant of biological nitrogen fixation, and the ecological significance thereof, including the codominant relationships between the rhizobia and the legumes and the associative processes of the non-legume plants, have been examined, with special focus placed on the associative processes of the latter plants. Furthermore, this study focused on the new synthetic biology technologies which have come to be developed, all towards the purpose of the insertion of the property of the nitrogen-fixing ability into the most farmed food grain crops. Through the integration of the latest developments of genomics, microbiological engineering, and microbial ecologies, these new technologies have the ability of reducing the worldwide use of chemical fertilizers, improving the soil quality, and ensuring the promotion of the sustainable agricultural production, particularly where the effects of the presently experienced problems of the loss of the greenhouse have been sensed.