Reduction of nitric oxide by denitrifying bacteria.

Two heterotrophic denitrifying bacteria, Paracoccus denitrificans and Pseudomonas denitrificans, have been shown to utilize nitric oxide (NO) as a terminal electron acceptor and succinate, yeast extract, and heat/alkali pretreated municipal sewage sludge as carbon and energy sources. Complete removal of NO (0.50%) from a feed gas sparged into the cultures was observed. It is suggested that reduction of NO may be a common feature of denitrifying bacteria and that a microbial process to dispose of NO(x) may be economically viable.