Until recently, the reductive amination of 2-oxoglutarate catalyzed by the enzyme glutamate dehydrogenase has been considered as the main reaction of ammonia assimilation in plants. Now there is convincing evidence that most of the inorganic nitrogen available to a plant is incorporated into the amide amino group of glutamine via the enzyme glutamine synthetase (L-glutamate ammonia ligase— ADP, GS). Subsequently [...]
Earth's atmosphere is nearly 80% nitrogen (N) but then the element is not sufficiently available to the organisms. It is known that some of the organisms have the capacity to assimilate molecular nitrogen and convert it into assumable form (Fig. 11-1). In general, four main types of organisms are recognized which can assimilate molecular nitrogen. These are symbiotic microorganisms inhabiting [...]
The below mentioned article provides a short note on reductase synthesis. Ammonia produced after nitrogen fixation is either immediately converted to organic nitrogen or to nitrate by nitrifying bacteria like Nitrosomonas in soil. The nitrates are then taken up by the plants and reduced to ammonia by a series of enzymes involving eight electrons transfer per molecule of NH3 formed. [...]