Beyond Denitrification: Alternative Routes to Dinitrogen
from: Nitrogen Cycling in Bacteria: Molecular Analysis (Edited by: James W. B. Moir). Caister Academic Press, U.K. (2011)
Although nitrate is a powerful electron acceptor, it was generally believed that it could not be used to activate recalcitrant substrates such as ammonium and methane. Only in the past decades, bacteria were identified that could activate these compounds. These bacteria have become known as anaerobic ammonium oxidizing ('anammox') bacteria and 'denitrifying methanotrophs'. Each makes use of a different and so far unique pathway of nitrate reduction with dinitrogen gas as the end product. Anammox bacteria activate ammonia with nitric oxide, leading to the production of hydrazine (N2H4). Denitrifying methanotrophs dismutate two molecules of nitric oxide into molecular oxygen (O2) and nitrogen (N2). In this chapter bacteria, pathways, cell biology and environmental relevance are discussed read more ...