Comparision of the stereospecificity and immunoreactivity of NADH-ferricyanide reductases in plant membranes

The substrate stereospecificity of NADH-ferricyanide reductase acivities in the inner mitochondrial membrane and peroxisomal membrane of potato (Solanum tuberosum L.) tubers, spinach (Spinacea oleracea L.) leaf plasma membrane, and red beetroot (Beta vulgaris L.) tonoplast were all specific for the beta-hydrogen of NADH, whereas the reductases in wheat root (Triticum aestivum L.) endoplasmic reticulum and potato tuber outer mitochondrial membrane were both alpha-hydrogen specific. In all isolated membrane fractions one or several polypeptides with an apparent size of 45 to 55 kD cross-readed with antibodies raised against a microsomal NADH-ferricyanide reductase on western blots.