Question

What does the enzyme nitrogenase do?

Answer 1

The biological process of nitrogen fixation is the first step in the nitrogen cycle. Certain bacterial species such as Rhizobium , Azotobacter , and others, as well as natural events, transform nitrogen in the atmosphere into ammonia (another type of nitrogen).
Atmospheric nitrogen, unlike carbon dioxide and oxygen, cannot be acquired through the stomata of leaves. Because plants cannot directly use the nitrogen gas present in the atmosphere. Nitrogen fixation is aided by a variety of microbes and natural phenomena.

Complete answer:
Nitrogenase is a Mo-Fe protein that breaks down nitrogen. They accelerate the conversion of atmospheric nitrogen to ammonia, the first stable nitrogen-fixing product. This process entails turning inert air nitrogen into useful nitrogen molecules including ammonia, nitrate, and amino acids, among others. There are two methods for nitrogen fixation: biological and abiological.
Nitrogenase (Nase) is an enzyme that converts nitrogen (${N_2}$) from the atmosphere into ammonia. The nitrogenase complex is made up of two distinct proteins. The FeMo protein attaches to the substrate and converts ${H^ + }$ and ${N_2}$ to ${H_2}$ and ammonia, whereas the Fe protein takes electrons from ferredoxin, hydrolyzes ATP, and lowers the FeMo protein.
Nitrogen-fixing bacteria use the enzyme nitrogenase complex, which is the major enzyme encoded by the nif genes, to transform atmospheric nitrogen into ammonia.
Because the enzyme nitrogenase is particularly sensitive to molecular oxygen, bacteria's root nodules have evolved to protect the enzyme from exposure to oxygen. Leghaemoglobin, an oxygen scavenger, is found in the nodules to protect these enzymes.

Note:
Some prokaryotes fix nitrogen without creating a symbiotic relationship with other organisms. They are aerobic and anaerobic microorganisms that dwell freely in the soil. - Examples include Azotobacter (aerobic) and Rhodospirillum (anaerobic). On the roots of non-leguminous plants like Alnus, the bacterium Frankia develops nitrogen-fixing nodules.