Gaseous organic substrates, such as methane and carbon monoxide, can also be used as substrates in denitrification. Among gaseous substrates, methane is one of the most studied; but some contradictions remain in the literature regarding methane metabolism. There is evidence that methane can be used as a terminal electron acceptor by some denitrifiers (Davies 1973).
Other investigators have suggested that methane oxidation requires aerobic or microaerophilic conditions, and that subsequent denitrification may be the result of a symbiotic relationship between two groups of organisms with different trophic requirements (Yull-Rhee et al. 1978).
It is likely that both phenomena occur, indicating two possible mechanisms for methane utilization during denitrification. Fewer studies have been published involving carbon monoxide, but there is evidence that it can be used as a substrate for denitrification (Park and Hegeman 1984).
Stoichiometric relationships for methane and carbon monoxide utilization have been proposed.
Was this article helpful?