Scientists from the United States have provided new evidence to suggest that microorganisms called archaea are important in the oxidation of ammonia.
Previous research has suggested that ammonia oxidation, in which ammonia is broken down into nitrite, was undertaken by chemolithotrophic ammonia-oxidising bacteria.
However, a new study due to be published in the journal Water Research has suggested that ammonia-oxidising archaea also play an important role.
"Ammonia oxidising archaea (AOA) are found to thrive in various habitats including hot/thermal springs, marine and fresh waters, soils, and wastewater treatment systems, where they may outnumber their counterpart, ammonia oxidising bacteria (AOB).
"Various molecular tools have been applied to study AOB and AOA and determine their abundance and community structure changes from natural and engineered systems. The presence of AOA in activated sludge opens new opportunities for elucidating its role of ammonia removal in wastewater treatment plants and wetlands."
For more information see the paper: You J, Das A, Dolan EM, Hu Z (2009) - Ammonia-oxidizing archaea involved in nitrogen removal. Water Res. 2009 Jan 31.