Ammonium transformed into nitrous oxide via nitric oxide by Pseudomonas putida Y-9 under aerobic conditions without hydroxylamine as intermediate. (April 2019)

• Record Type: Journal Article
• Authors: Huang, Xuejiao; Xu, Yi; He, Tengxia; Jia, Hongjie; Feng, Mi; Xiang, Shudi; Wang, Shutong; Ni, Jiupai; Xie, Deti; Li, Zhenlun
• Is Part Of: Bioresource technology. Volume 277(2019)
• Page Start: 87
• Page End: 93
• Publication Date: 2019-04
• Subjects: Pseudomonas putida -- Aerobic -- Hydroxylamine transform pathway -- Ammonium oxidation pathway; Biomass -- Periodicals; Biomass energy -- Periodicals; Bioremediation -- Periodicals; Agricultural wastes -- Periodicals; Factory and trade waste -- Periodicals; Organic wastes -- Periodicals; Bioénergie -- Périodiques; Déchets agricoles -- Périodiques; Déchets industriels -- Périodiques; Déchets organiques -- Périodiques; Déchets (Combustible) -- Périodiques; 662.88
• DOI: 10.1016/j.biortech.2019.01.040
• Languages: English
• ISSNs: 0960-8524

Abstract

Graphical abstract: Highlights: NH4 + oxidized to N2 O by P. putida Y-9 without the accumulation of NH2 OH and NO2 − under aerobic conditions. NH2 OH inhibits the transformation efficiency of NH4 + to N2 O. NH4 + could accelerate the transformation of NH2 OH to NO2 − . Ammonia monooxygenase doesn't exist in P. putida Y-9. The ammonium oxidation pathway of P. putida Y-9 may be NH4 + → NO → N2 O. Abstract: Previous studies have reported that hydroxylamine (NH2 OH) is an inevitable intermediate of the ammonium (NH4 + ) oxidation pathway under aerobic conditions. In this study, Pseudomonas putida Y-9 was found to oxidize ammonium into N2 O via NO without the accumulation of NH2 OH and NO2 − under aerobic conditions. NH2 OH was nearly completely transformed into NO2 − whether NH4 + was present in the medium, and NH4 + could accelerate the transformation of NH2 OH to NO2 − by promoting Y-9 growth. NH4 + was oxidized rapidly by Y-9 with or without the presence of NH2 OH in the medium, and the decrease of total nitrogen reached 30.65 mg/L and 39.38 mg/L, respectively, which indicates that NH2 OH inhibits the transformation efficiency of NH4 + to N2 O. Gene amplification and enzyme assays demonstrated that ammonia monooxygenase doesn't exist in Y-9. All results show that NH4 + can be transformed into N2 O via NO by Y-9 under aerobic conditions without NH2 OH as intermediate.