Capability of N2O reduction of a facultative N2O reducer

Abstract:

[Objective] A nitrous oxide reducing bacterium (DJ7) was isolated from paddy soil and its ability to reduce N₂O was detected under different incubation conditions. Aiming to understand the mechanisms of N₂O reduction and supply theoretical basis for regulation of N₂O emission. [Methods] The strain was isolated by microbial enrichment culture and identified by homogeneous analysis of its sequences of nosZ and 16S rRNA gene with the database of NCBI. The abilities of N₂O-reducing of DJ7 at different temperatures and O₂ concentrations were determined by measuring the amount of N₂O reduction through GC. [Results] The strain was characterized as Pseudomonas and contained nosZ gene, its N₂O reduction rate was more than 0.0219 μmol/min under anaerobic at 30℃. Although the increase of air O₂ concentration and shifts of incubation temperature at either direction resulted decreases of the capability of N₂O reduction, it maintained a certain ability in N₂O reduction. [Conclusion] The strain is an active facultative N₂O reducer belonging to Pseudomonas and possesses strong ability to reduce N₂O, especially under anaerobic condition. This strain may provide a new idea to alleviate the N₂O issue and play an active role in the ecological environment.

Key words:nitrous oxide reducer;Pseudomonas sp.;N₂O-reducing ability;nosZ gene