Methane-oxidizing archaea, aerobic methanotrophs and nitrifiers coexist with methane as the sole carbon source

Autor(es)

Costa, R. B. ^[1] ; Okada, D. Y. ^[2] ; Delforno, T. P. ^[3] ; Foresti, E. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Sao Carlos Sch Engn EESC, Dept Hydraul & Sanitat, Biol Proc Lab, Engn Ambiental Bloco 4-F, Av Joao Dagnone 1100, BR-13563120 Sao Carlos, SP - Brazil

^[2] Univ Estadual Campinas, Sch Technol, Rua Paschoal Marmo, 1888 Jd Nova Italia, BR-13484332 Limeira, SP - Brazil

^[3] Campinas Univ, Microbial Resources Div, Res Ctr Chem Biol & Agr CPQBA, UNICAMP, BR-13081970 Campinas, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: INTERNATIONAL BIODETERIORATION & BIODEGRADATION; v. 138, p. 57-62, MAR 2019.
• Citações Web of Science: 1

Resumo

Methane oxidation plays a key role in carbon and nutrient cycling and has the potential to be applied in engineered bioprocesses, including wastewater and gas treatments. To provide insights into the dynamics of the methanotrophic community under microoxic and anoxic conditions, two sequencing batch reactors under microoxic (MO2-SBR) and anoxic (Anox-SBR) conditions were operated. The methane oxidation rate was higher under microoxic conditions (5.3 +/- 0.9 mmol.batch cycle(-1)) than anoxic conditions (3.1 +/- 0.8 mmol.batch cycle(-1)). Higher methane oxidation led to higher nitrate reduction rates (9.4 +/- 2.5 mgN.batch cycle(-1) and 4.0 +/- 2.0 mg N.batch cycle(-1) for MO2-SBR and Anox-SBR, respectively). 16S rDNA sequencing revealed reads corresponding to aerobic oxidizers (0.5% and 2.0% for Anox-SBR and MO2-SBR, respectively), to the Nitrosospira genus (26.6% and 28.3% for Anox-SBR and MO2-SBR, respectively), and to anaerobic methane-oxidizing archaea (ANME) (4.0% and 3.5% for Anox-SBR and for MO2-SBR, respectively). Nitrifying organisms are capable of oxidizing methane due to the homology between the enzymes ammonia monooxygenase and methane monooxygenase. These findings seem to indicate that methane oxidation is carried out by versatile metabolic pathways and couples with other biological processes, such as denitrification. (AU)

• Processo FAPESP: 09/15984-0 - Produção de bioenergia no tratamento de águas residuárias e adequação ambiental dos efluentes e resíduos gerados
• Beneficiário: Marcelo Zaiat
• Modalidade de apoio: Auxílio à Pesquisa - Temático