Metatranscriptomic and metagenomic description of the bacterial nitrogen metabolism in waste water wet oxidation effluents

Heliyon

卷:3

Gautier Calmin¹  Romain Chablais²  Julien Crovadore²  Bastien Cochard²  François Lefort²  Vice Soljan³ 

[1] Faculty of Engineering and Architecture, HES-SO University of Applied Sciences and Arts Western Switzerland, Rue de la Jeunesse 1, 2800 Delémont, Switzerland;

[2] Plants and pathogens group, Institute Land Nature and Environment, Hepia, HES-SO University of Applied Sciences and Arts Western Switzerland, 150 route de Presinge, 1254 Jussy, Switzerland;

[3] Puratis Sàrl, EPFL Innovation Park, Building C, 1015 Lausanne, Switzerland;

关键词: Applied sciences;    Biological sciences;    Environmental science;    Genetics;    Microbiology;   

DOI  :  

来源: DOAJ

【 摘 要 】

Anaerobic digestion is a common method for reducing the amount of sludge solids in used waters and enabling biogas production. The wet oxidation process (WOX) improves anaerobic digestion by converting carbon into methane through oxidation of organic compounds. WOX produces effluents rich in ammonia, which must be removed to maintain the activity of methanogens. Ammonia removal from WOX could be biologically operated by aerobic granules. To this end, granulation experiments were conducted in 2 bioreactors containing an activated sludge (AS). For the first time, the dynamics of the microbial community structure and the expression levels of 7 enzymes of the nitrogen metabolism in such active microbial communities were followed in regard to time by metagenomics and metatranscriptomics. It was shown that bacterial communities adapt to the wet oxidation effluent by increasing the expression level of the nitrogen metabolism, suggesting that these biological activities could be a less costly alternative for the elimination of ammonia, resulting in a reduction of the use of chemicals and energy consumption in sewage plants. This study reached a strong sequencing depth (from 4.4 to 7.6 Gb) and enlightened a yet unknown diversity of the microorganisms involved in the nitrogen pathway. Moreover, this approach revealed the abundance and expression levels of specialised enzymes involved in nitrification, denitrification, ammonification, dissimilatory nitrate reduction to ammonium (DNRA) and nitrogen fixation processes in AS.

【 授权许可】

Unknown