Index >> Nitrogen Fixation by Free Living Blue-Green Alage >> Ammonia Assimilation

Ammonia Assimilation

As mentioned earlier, N₂ fixation results in NH₄ formation in heterocysts which reacts with glutamate translated from vegetative cells to form vegetative cells to form glutamine with the aid of glutamine synthetase. Most of this glutamine gets back into vegetative cells where it is metabolized into glutamate and other amino acids by glutamate synthase or glutamine oxoglutarate amidotransferase (GOGAT) located in vegetative cells.

The glutamate formed may eventually form a substrate for more glutamine synthesis or else be transported back into heterocysts. In this way, the first stable nitrogen fixation is NH₄⁺ and the first organic product of assimilation of NH₄⁺ is glutamine followed by glutamate. Alanine may be formed through alanine aspartate in other species by transamination reaction probably from glutamate.