Microbial nitrogen Fixation

Nitrogen is vital for all life forms, essential for producing proteins, nucleic acids, and chlorophyll. Although nitrogen gas (N2) makes up 78% of the atmosphere, most organisms cannot use it directly, except for some nitrogen-fixing bacteria. These bacteria break the nitrogen bond to produce ammonia (NH3), which is incorporated into amino acids, proteins, nucleic acids, and chlorophyll.

A subgroup of these bacteria, rhizobia, forms a symbiosis with legume plants, such as peas and beans. Rhizobia infect the plant's roots, forming nodules where nitrogen is fixed into ammonia, which the plant uses. In exchange, the plant supplies the bacteria with carbon and energy. This symbiosis benefits both parties: the plant receives nitrogen, and the bacteria get the nutrients they need. Additional benefits include:

- Legume grains (peas, lentils, soybeans) are high in protein, benefiting human and animal diets.
- Nitrogen from legume roots enriches the soil.
- Nitrogen leaching is minimized, reducing environmental impact.
- Legume root growth fosters diverse microorganisms, enhancing soil fertility.

Beyond legumes, other nitrogen-fixing bacteria also contribute to plant growth through similar symbiotic relationships, playing a key role in the nitrogen cycle. This process reduces the need for chemical fertilizers, helping to prevent environmental problems like global warming and eutrophication. It also promotes the production of high-protein grains essential for food security in impoverished regions.