title: Techniques for investigating hydroxylamine disproportionation by hydroxylamine oxidoreductases.
abstract: Hydroxylamine, an important intermediate in ammonia oxidation by ammonia oxidizing bacteria (AOB), is inherently unstable with respect to disproportionation. The process is slow in neutral solutions, but could potentially be catalyzed by enzymes such as the hydroxylamine oxidoreductases, which normally catalyze the oxidation of ammonia to nitrite in the AOB. Disproportionation could be physiologically important to some AOB under microaerobic conditions, and could also confound in vitro analyses if it occurs and is not taken into consideration. This chapter presents methods for detecting ammonia, nitric oxide, nitrite, nitrous oxide, and isotopically labeled dinitrogen, which are the most thermodynamically favored products of hydroxylamine disproportionation.
authors.affiliation: Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin, USA.
authors.forename: A Andrew
authors.initials: AA
authors.lastname: Pacheco
authors.forename: Jennifer
authors.initials: J
authors.lastname: McGarry
authors.forename: Joshua
authors.initials: J
authors.lastname: Kostera
authors.forename: Angel
authors.initials: A
authors.lastname: Corona
mesh_terms: D000641:Ammonia / Q000032:analysis*; D055162:Biocatalysis; D015374:Biosensing Techniques / Q000379:methods*; D019811:Hydroxylamine; D009569:Nitric Oxide / Q000032:analysis*; D009573:Nitrites / Q000032:analysis*; D009609:Nitrous Oxide / Q000032:analysis*; D010084:Oxidation-Reduction; D010088:Oxidoreductases / Q000378:metabolism
chemical_list: D009573:Nitrites; D019811:Hydroxylamine; D009569:Nitric Oxide; D000641:Ammonia; D010088:Oxidoreductases; C021401:hydroxylamine dehydrogenase; D009609:Nitrous Oxide