Give the biochemical events occurring in the root nodule of a pulse plant. What is the end product? What is its fate?
Nodule consists of all the biochemicals like enzyme nitrogenase and Leg Haemoglobin.The process of nitrogen fixation involves the conversion of free nitrogen in the air into Ammonia or other nitrogenous compounds in the presence of enzyme Nitrogenase.
The end product of the biochemical events is Ammonia (NH3).
Fate of Ammonia:The Ammonia produced through nitrogen fixation is incorporated in the amino acids as amino group.At physiological pH NH3 group is protonated to NH4+ group .
The two events by which NH4+ group is incorporated into amino acids are:
1. Reductive Amination:In this reaction alpha Ketoglutaric acid forms glutamate.In this reaction Ammonia reacts with a-ketoglutaric acid to form glutamate.
2. Transamination: In this reaction amino group (NH2) transfers from one amino acid to another amino acid transaminase enzyme catalyses this reaction.