1Division of Biochemistry, Indian Agricultural Research Institute, New Delhi 110 012, India
2Nuclear Research Laboratory, Indian Agricultural Research Institute, New Delhi 110 012, India
*Corresponding author
1Present Address: Division of Crop Physiology & Biochemistry, Central Potato Research Institute, Shimla 171 001, H.P., India.
A single isoform, NAOH: nitrate reductase (NR), was purified 500 folds from sunflower leaves by affinity chromatography on Blue Sepharose CL-68. Purified NR had a pH optima of 7.25 and a molecular weight of 210 kD. In SDS-PAGE, two bands of 47 and 56 kD were obtained. NADH: ferric citrate reductase activity was copurified with NR with a specific activity of 2. The Vmax of NADHi ferrc citrate reductase was 8.69 units mg−1 protein and the apparent Km for ferric citrate was 0.435 mM.
nitrate reductase, sunflower, blue Sepharose CL-6B, molecular weight, sub-unit, pH optima, ferric citrate reductase