Ammonia Assimilation - Inorganic Nitrogen and Sulphur Metabolism

Nitrogen (N₂) gas and NO₃ are the most common available forms of inorganic nitrogen. Both are enzymatically reduced to ammonia because it is only ammonia that is-incorporated into organic form. Since amino acids either free or part of proteins are the predominant form of organic nitrogen, the major product of ammonia assimilation is usually considered to be amino nitrogen.