Ferredoxins are iron-sulfur proteins that transfer electrons in a wide variety of metabolic reactions. This ferredoxin could play a role in regulating gene expression by interacting directly with DNA. Binds 1 [4Fe-4S] cluster. Binds 1 [3Fe-4S] cluster. E(0) is -450 mV for the 3Fe-4S, and -645 mV for the 4Fe-4S clusters.