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Biotransformation of Two Pharmaceuticals by the Ammonia-Oxidizing Archaeon Nitrososphaera gargensis.

Authors :
Men, Yujie
Ping Han
Helbling, Damian E.
Jehmlich, Nico
Herbold, Craig
Gulde, Rebekka
Onnis-Hayden, Annalisa
Gu, April Z.
Johnson, David R.
Wagner, Michael
Fenner, Kathrin
Source :
Environmental Science & Technology. 5/3/2016, Vol. 50 Issue 9, p4682-4692. 11p.
Publication Year :
2016

Abstract

The biotransformation of some micropollutants has previously been observed to be positively associated with ammonia oxidation activities and the transcript abundance of the archaeal ammonia monooxygenase gene (amoA) in nitrifying activated sludge. Given the increasing interest in and potential importance of ammonia-oxidizing archaea (AOA), we investigated the capabilities of an AOA pure culture, Nitrososphaera gargensis, to biotransform ten micropollutants belonging to three structurally similar groups (i.e., phenylureas, tertiary amides, and tertiary amines). N. gargensis was able to biotransform two of the tertiary amines, mianserin (MIA) and ranitidine (RAN), exhibiting similar compound specificity as two ammonia-oxidizing bacteria (AOB) strains that were tested for comparison. The same MIA and RAN biotransformation reactions were carried out by both the AOA and AOB strains. The major transformation product (TP) of MIA, a-oxo MIA was likely formed via a two-step oxidation reaction. The first hydroxylation step is typically catalyzed by monooxygenases. Three RAN TP candidates were identified from nontarget analysis. Their tentative structures and possible biotransformation pathways were proposed. The biotransformation of MIA and RAN only occurred when ammonia oxidation was active, suggesting cometabolic transformations. Consistently, a comparative proteomic analysis revealed no significant differential expression of any protein-encoding gene in N. gargensis grown on ammonium with MIA or RAN compared with standard cultivation on ammonium only. Taken together, this study provides first important insights regarding the roles played by AOA in micropollutant biotransformation. [ABSTRACT FROM AUTHOR]

Details

Language :
English
ISSN :
0013936X
Volume :
50
Issue :
9
Database :
Academic Search Index
Journal :
Environmental Science & Technology
Publication Type :
Academic Journal
Accession number :
115779075
Full Text :
https://doi.org/10.1021/acs.est.5b06016