Light-driven nitrous oxide production via autotrophic denitrification by self-photosensitized Thiobacillus denitrificans.
Environ Int
; 127: 353-360, 2019 06.
Article
em En
| MEDLINE
| ID: mdl-30954721
ABSTRACT
N2O (Nitrous oxide, a booster oxidant in rockets) has attracted increasing interest as a means of enhancing energy production, and it can be produced by nitrate (NO3-) reduction in NO3--loading wastewater. However, conventional denitrification processes are often limited by the lack of bioavailable electron donors. In this study, we innovatively propose a self-photosensitized nonphototrophic Thiobacillus denitrificans (T. denitrificans-CdS) that is capable of NO3- reduction and N2O production driven by light. The system converted >72.1⯱â¯1.1% of the NO3--N input to N2ON, and the ratio of N2O-N in gaseous products was >96.4⯱â¯0.4%. The relative transcript abundance of the genes encoding the denitrifying proteins in T. denitrificans-CdS after irradiation was significantly upregulated. The photoexcited electrons acted as the dominant electron sources for NO3- reduction by T. denitrificans-CdS. This study provides the first proof of concept for sustainable and low-cost autotrophic denitrification to generate N2O driven by light. The findings also have strong implications for sustainable environmental management because the sunlight-triggered denitrification reaction driven by nonphototrophic microorganisms may widely occur in nature, particularly in a semiconductive mineral-enriched aqueous environment.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Thiobacillus
/
Luz
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Óxido Nitroso
Idioma:
En
Revista:
Environ Int
Ano de publicação:
2019
Tipo de documento:
Article
País de afiliação:
China