Using RNA-Stable isotope probing to investigate methane oxidation metabolites and active microbial communities in methane oxidation coupled to denitrification.
Chemosphere
; 357: 142067, 2024 Jun.
Article
em En
| MEDLINE
| ID: mdl-38643845
ABSTRACT
The active denitrifying communities performing methane oxidation coupled to denitrification (MOD) were investigated using samples from an aerobic reactor (â¼20% O2 and 2% CH4) and a microaerobic reactor (2% O2, 2% CH4) undertaking denitrification. The methane oxidation metabolites excreted in the reactors were acetate, methanol, formate and acetaldehyde. Using anaerobic batch experiments supplemented with exogenously supplied 13C-labelled metabolites, the active denitrifying bacteria were identified using 16S rRNA amplicon sequencing and RNA-stable isotope probing (RNA-SIP). With the aerobic reactor (AR) samples, the maximum NO3- removal rates were 0.43 mmol g-1 d-1, 0.40 mmol g-1 d-1, 0.33 mmol g-1 d-1 and 0.10 mmol g-1 d-1 for exogenously supplied acetate, formate, acetaldehyde and methanol batch treatments respectively, while with the microaerobic reactor (MR) samples, the maximum NO3- removal rates were 0.41 mmol g-1 d-1, 0.33 mmol g-1 d-1, 0.38 mmol g-1 d-1 and 0.14 mmol g-1 d-1 for exogenously supplied acetate, formate, acetaldehyde and methanol batch treatments respectively. The RNA-SIP experiments with 13C-labelled acetate, formate, and methanol identified Methyloversatilis, and Hyphomicrobium as the active methane-driven denitrifying bacteria in the AR samples, while Pseudoxanthomonas, Hydrogenophaga and Hyphomicrobium were the active MOD bacteria in the MR samples. Collectively, all the data indicate that formate is a key cross-feeding metabolite excreted by methanotrophs and consumed by denitrifiers performing MOD.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Oxirredução
/
Reatores Biológicos
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Desnitrificação
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Metano
Idioma:
En
Ano de publicação:
2024
Tipo de documento:
Article