HUSCAP logo Hokkaido Univ. logo

Hokkaido University Collection of Scholarly and Academic Papers >
Graduate School of Engineering / Faculty of Engineering >
Peer-reviewed Journal Articles, etc >

Identification and isolation of active N2O reducers in rice paddy soil

Files in This Item:
ISMEj5-12_1844-1856.pdf425.47 kBPDFView/Open
Please use this identifier to cite or link to this item:http://hdl.handle.net/2115/49343

Title: Identification and isolation of active N2O reducers in rice paddy soil
Authors: Ishii, Satoshi Browse this author
Ohno, Hiroki Browse this author
Tsuboi, Masahiro Browse this author
Otsuka, Shigeto Browse this author
Senoo, Keishi Browse this author
Keywords: denitrification
Herbaspirillum
nitrous oxide
rice paddy soil
single-cell isolation
stable isotope probing
Issue Date: Dec-2011
Publisher: Nature Publishing Group
Journal Title: ISME Journal
Volume: 5
Issue: 12
Start Page: 1936
End Page: 1945
Publisher DOI: 10.1038/ismej.2011.69
Abstract: Dissolved N2O is occasionally detected in surface and ground water in rice paddy fields, whereas little or no N2O is emitted to the atmosphere above these fields. This indicates the occurrence of N2O reduction in rice paddy fields; however, identity of the N2O reducers is largely unknown. In this study, we employed both culture-dependent and culture-independent approaches to identify N2O reducers in rice paddy soil. In a soil microcosm, N2O and succinate were added as the electron acceptor and donor, respectively, for N2O reduction. For the stable isotope probing (SIP) experiment, 13C-labeled succinate was used to identify succinate-assimilating microbes under N2O-reducing conditions. DNA was extracted 24 h after incubation, and heavy and light DNA fractions were separated by density gradient ultracentrifugation. Denaturing gradient gel electrophoresis and clone library analysis targeting the 16S rRNA and the N2O reductase gene were performed. For culture-dependent analysis, the microbes that elongated under N2O-reducing conditions in the presence of cell division inhibitors were individually captured by a micromanipulator and transferred to a low-nutrient medium. The N2O-reducing ability of these strains was examined by gas chromatography/mass spectrometry. Results of the SIP analysis suggested that Burkholderiales and Rhodospirillales bacteria dominated the population under N2O-reducing conditions, in contrast to the control sample (soil incubated with only 13C-succinate added). Results of the single-cell isolation technique also indicated that the majority of the N2O-reducing strains belonged to the genera Herbaspirillum (Burkholderiales) and Azospirillum (Rhodospirillales). In addition, Herbaspirillum strains reduced N2O faster than Azospirillum strains. These results suggest that Herbaspirillum spp. may have an important role in N2O reduction in rice paddy soils.
Type: article (author version)
URI: http://hdl.handle.net/2115/49343
Appears in Collections:工学院・工学研究院 (Graduate School of Engineering / Faculty of Engineering) > 雑誌発表論文等 (Peer-reviewed Journal Articles, etc)

Submitter: 石井 聡

Export metadata:

OAI-PMH ( junii2 , jpcoar )

MathJax is now OFF:


 

 - Hokkaido University