Alga Chlorella Fusca Research Articles

Characterization of a flavodoxin from the green alga chlorella

A new flavoprotein has been isolated and purified to homogeneity from the green alga Chlorella fusca . It has characteristics comparable to those of phytoflavin from the blue-green alga Anacystis nidulans or flavodoxin from various bacteria. Chlorella flavodoxin can replace spinach and Chlorella ferredoxin in photosynthetic NADP reduction of broken chloroplasts. Its molecular weight is 22 000. One mole of FMN is present per mole of protein. The extinction coefficient at 464 nm is 10 000 M −1 cm −1. Reduction of the flavoprotein proceeds via a blue flavosemiquinone radical. The amino acid composition reveals a close relationship to bacterial flavodoxins.