Partial Purification of the NADH-Nitrate Reductase Complex from Chlorella pyrenoidosa

Abstract

The nitrate reductase complex from Chlorella pyrenoidosa has been purified by a procedure which includes as main steps, ammonium sulfate fractionation, polyethylene glycol treatment, and DEAE-cellulose chromatography. The Michaelis constants for NADH, FAD, and NO(3) (-) in the NADH-nitrate reductase assay are 10 mum, 2.6 mum, and 0.23 mm, respectively. Heat treatment exerts varying effects on the enzymatic activities associated with the nitrate reductase complex.