May be involved in the metabolism of 1-methylnicotinamide (MNA). Linked to regulation of longevity through generation of reactive oxygen species, where it probably functions in a pathway downstream of the sirtuin sir-2.1 and the nicotinamide N-methyltransferase anmt-1. an aldehyde + H2O + O2 = a carboxylate + H(+) + H2O2 Binds 2 [2Fe-2S] clusters per subunit. Binds 1 FAD per subunit. Binds 1 Mo-molybdopterin (Mo-MPT) cofactor per subunit. RNAi-mediated knockdown reduces both the longevity-extending effects and generation of reactive oxygen species when exposed to 1 microM N1-methylnicotinamide. Belongs to the xanthine dehydrogenase family.