The molecular weight of NADPH-cytochrome C reductase isolated by immunoprecipitation from detergent-solubilized rat liver microsomes

The molecular weight of detergent-solubilized NADPH-cytochrome c reductase from rat liver microsomes has been estimated to be 79,000. The method used for this determination involves immunoprecipitation of deoxycholate-solubilized enzyme from ¹²⁵I-labeled microsomal proteins. The antibody was prepared against a purified preparation of Bromelain-solubilized enzyme (molecular weight 71,000). The immunoprecipitate was then subjected to SDS-polyacrylamide gel electrophoresis and the enzyme located by ¹²⁵I-gamma counting.