Catalyzes the oxidation of aldehydes to their corresponding carboxylic acids. May have a pyroglycolytic (saccharolytic) role. an aldehyde + H2O + 2 oxidized [2Fe-2S]-[ferredoxin] = a carboxylate + 3 H(+) + 2 reduced [2Fe-2S]-[ferredoxin] Binds 1 [4Fe-4S] cluster per subunit. Binds 1 W-bis(molybdopterin guanine dinucleotide) (W-bis-MGD) cofactor per subunit. Inhibited by arsenite, iodoacetate and cyanide. Significant activity only with aliphatic and aromatic aldehydes and only at low concentration (0.5 mM). Optimum pH is above 10. Optimum temperature is above 90 degrees Celsius. Homodimer. A significant amount of formaldehyde ferredoxin oxidoreductase activity has been observed. Belongs to the AOR/FOR family.