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Characteristics of microbial denitrification under different aeration intensities: Performance, mechanism, and co-occurrence network.
Yuan, Haiguang; Huang, Shaobin; Yuan, Jianqi; You, Yingying; Zhang, Yongqing.
Afiliação
  • Yuan H; School of Environment and Energy, South China University of Technology, Higher Education Mega Center, Guangzhou 510006, PR China; Guangdong Ecological Environment Control Engineering Technology Research Center, South China University of Technology, Higher Education Mega Center, Guangzhou 510006, PR
  • Huang S; School of Environment and Energy, South China University of Technology, Higher Education Mega Center, Guangzhou 510006, PR China; Guangdong Ecological Environment Control Engineering Technology Research Center, South China University of Technology, Higher Education Mega Center, Guangzhou 510006, PR
  • Yuan J; School of Environment and Energy, South China University of Technology, Higher Education Mega Center, Guangzhou 510006, PR China; Guangdong Ecological Environment Control Engineering Technology Research Center, South China University of Technology, Higher Education Mega Center, Guangzhou 510006, PR
  • You Y; School of Environment and Energy, South China University of Technology, Higher Education Mega Center, Guangzhou 510006, PR China; Guangdong Ecological Environment Control Engineering Technology Research Center, South China University of Technology, Higher Education Mega Center, Guangzhou 510006, PR
  • Zhang Y; School of Environment and Energy, South China University of Technology, Higher Education Mega Center, Guangzhou 510006, PR China.
Sci Total Environ ; 754: 141965, 2021 Feb 01.
Article em En | MEDLINE | ID: mdl-32911146
This study aimed to explore how dissolved oxygen (DO) affected the characteristics and mechanisms of denitrification in mixed bacterial consortia. We analyzed denitrification efficiency, intracellular nicotinamide adenine dinucleotide (NADH), relative expression of functional genes, and potential co-occurrence network of microorganisms. Results showed that the total nitrogen (TN) removal rates at different aeration intensities (0.00, 0.25, 0.63, and 1.25 L/(L·min)) were 0.93, 1.45, 0.86, and 0.53 mg/(L·min), respectively, which were higher than previously reported values for pure culture. The optimal aeration intensity was 0.25 L/(L·min), at which the maximum NADH accumulation rate and highest relative abundance of napA, nirK, and nosZ were achieved. With increased aeration intensity, the amount of electron flux to nitrate decreased and nitrate assimilation increased. On one hand, nitrate reduction was primarily inhibited by oxygen through competition for electron donors of a certain single strain. On the other hand, oxygen was consumed rapidly by bacteria by stimulating carbon metabolism to create an optimal denitrification niche for denitrifying microorganisms. Denitrification was performed via inter-genus cooperation (competitive interactions and symbiotic relationships) between keystone taxa (Azoarcus, Paracoccus, Thauera, Stappia, and Pseudomonas) and other heterotrophic bacteria (OHB) in aeration reactors. However, in the non-aeration case, which was primarily carried out based on intra-genus syntrophy within genus Propionivibrio, the co-occurrence network constructed the optimal niche contributing to the high TN removal efficiency. Overall, this study enhanced our knowledge about the molecular ecological mechanisms of aerobic denitrification in mixed bacterial consortia and has theoretical guiding significance for further practical application.
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Texto completo: 1 Coleções: 01-internacional Base de dados: MEDLINE Assunto principal: Reatores Biológicos / Desnitrificação Idioma: En Revista: Sci Total Environ Ano de publicação: 2021 Tipo de documento: Article País de publicação: Holanda

Texto completo: 1 Coleções: 01-internacional Base de dados: MEDLINE Assunto principal: Reatores Biológicos / Desnitrificação Idioma: En Revista: Sci Total Environ Ano de publicação: 2021 Tipo de documento: Article País de publicação: Holanda