Phytochrome-dependent Reduction of Nicotinamide Nucleotides in the Mitochondrial Fraction Isolated from Etiolated Pea Epicotyls

摘要: When mitochondria isolated from etiolated pea (Pisum sativum cv. Alaska) epicotyls were exposed briefly to red light, their ability reduce exogenous NADP was enhanced. The light effect reversed by far light. Photoreversible absorbance changes between 730 nm and 800 spectrophotometrically detected in the purified its membrane fraction. dehydrogenase activity heat-labile dependent on presence of magnesium ion appropriate substrates such as glucose 6-phosphate, isocitrate, pyruvate, 6-phosphogluconate, succinate. photoreversible seen only for a few minutes after irradiation, cancelled hypotonic treatment or addition Triton X-100. A similar but lesser observed microsome fraction, whereas no response with supernatant fraction resulting centrifugation at 105g 30 minutes.