Chemical synthesis of ferredoxin with 4 selenocysteine residues using a segment condensation method.

Ferredoxin (Fd) is an electron carrier protein containing a [2Fe-2S] cluster. In this paper, we synthesized Se-Fd, in which four Cys residues coordinated to the cluster are substituted to selenocysteine. After the one-pot segment coupling by the thioester method, followed by deprotection and cluster loading, the desired Se-Fd was successfully obtained.