Nitrite oxidation to nitrate (NO3−), though traditionally believed to be facilitated by Nitrobacter spp. (nitro referring the formation of a nitro functional group), is now known to be facilitated in the environment almost exclusively by Nitrospira spp.
A oxidación do nitrito a nitrato (NO3−), aínda que tradicionalmente se cría que era realizado polas Nitrobacter spp. (forman o grupo funcional nitro), agora crese que no ambiente está facilitado case exclusivamente polas Nitrospira spp.