Question

Name the most crucial enzyme found in root nodules for N2 fixation? Does it require a special pink coloured pigment for its functioning? Elaborate.

Answer 1

Crucial enzyme for nitrogen fixation:

● The enzyme nitrogenase, present in Rhizobium, helps in the conversion of atmospheric nitrogen into two molecules of ammonia.

● It is a Mo-Fe protein and is inactivated in the presence of oxygen.


Pigment required for enzyme function:

Leg-haemoglobin is an oxygen scavenging pink-colored pigment present in the root nodules of the leguminous plants. It protects nitrogenase from oxygen exposure by maintaining an anaerobic environment. This keeps the function of nitrogenase unaltered.