Expression of Assimilatory Nitrate and Nitrite Reductase of Rhizobium meliloti

To investigate the expression of assimilatory nitrate-and nitrite reductase activity of Rhizobium meliloti SU 47.

Rhizobium cell were grown in medium, after 20 hrs cells were washed with potassium phosphate buffer and assayed the enzyme activity through nitrite estimation.

Expression of assimilatory nitrate-and nitrite reductase was observed in GTS/glutamate medium. The enzymes were inducible in nature since it expressed only in presence of nitrate or nitrite. Ammonium inhibited the enzyme activity. Cyanate acted as a gratituous inducer of both the enzymes. Molybdenum acts as modulator whereas tungstate as an inhibitor of the enzyme.

Both the enzymes, assimilatory nitrate-and nitrite reductases expressed in GTS/glutamate medium in presence of nitrate.