Abstract
Two proteins showing chloroplast ferredoxin activity were separated by DEAE-cellulose column chromatography of an extract of the blue-green alga Anacystis nidulans. One of the proteins was identified as a chloroplast-type ferredoxin. The other protein, named phytoflavin, could not be identified with either a chloroplast - or a bacterial-type ferredoxin. It catalyzed the photoreduction of nicotinamide adenine dinucleotide phosphate by washed chloroplasts in the absence of added ferredoxin. The flavin component of phytoflavin adenine mononucleotide.