. "Catalysis of an oxidation-reduction (redox) reaction in which an aldehyde or ketone (oxo) group acts as a hydrogen or electron donor and reduces an iron-sulfur protein." . . "oxidoreductase activity, acting on the aldehyde or oxo group of donors, iron-sulfur protein as acceptor" . "oxidoreductase activity, acting on the aldehyde or oxo group of donors, iron-sulphur protein as acceptor" . . . . . . . . . . .