title: Simultaneous enrichment of denitrifying anaerobic methane-oxidizing microorganisms and anammox bacteria in a hollow-fiber membrane biofilm reactor.
abstract: In this study, the coculture system of denitrifying anaerobic methane oxidation (DAMO) microbes and anaerobic ammonium oxidation (anammox) bacteria was successfully enriched in a hollow-fiber membrane biofilm reactor (HfMBR) using freshwater sediment as the inoculum. The maximal removal rates of nitrate and ammonium were 78 mg N/L/day (131 mg N/m2/day) and 26 mg N/L/day (43 mg N/m2/day), respectively. Due to the high rate of methane mass transfer in HfMBR, the activity of DAMO archaea continued to increase during the enrichment period, indicating that HfMBR could be a powerful tool to enrich DAMO microorganisms. Effects of partial methane pressure, temperature, and pH on the cocultures were obvious. However, the microbial activity in HfMBR could be recovered quickly after the shock change of environmental factors. Furthermore, the result also found that DAMO bacteria likely had a stronger competitive advantage than anammox bacteria under the operating conditions in this study. High-throughput sequencing 16S rRNA genes illustrated that the dominant microbes were NC10, Euryarchaeota, Proteobacteria, Planctomycetes, and Chlorobi with relative abundance of 38.8, 26.2, 13.78, 6.2, and 3.6 %, respectively.
authors.affiliation: CAS Key Laboratory for Urban Pollutant Conversion, Department of Chemistry, University of Science and Technology of China, Hefei, Anhui, 230026, People's Republic of China.
authors.forename: Zhao-Wei
authors.initials: ZW
authors.lastname: Ding
authors.affiliation: CAS Key Laboratory for Urban Pollutant Conversion, Department of Chemistry, University of Science and Technology of China, Hefei, Anhui, 230026, People's Republic of China.
authors.forename: Yong-Ze
authors.initials: YZ
authors.lastname: Lu
authors.affiliation: CAS Key Laboratory for Urban Pollutant Conversion, Department of Chemistry, University of Science and Technology of China, Hefei, Anhui, 230026, People's Republic of China.
authors.forename: Liang
authors.initials: L
authors.lastname: Fu
authors.affiliation: Advanced Environmental Biotechnology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, Singapore, 637141, Singapore. dingjing@ntu.edu.sg.
authors.forename: Jing
authors.initials: J
authors.lastname: Ding
authors.affiliation: CAS Key Laboratory for Urban Pollutant Conversion, Department of Chemistry, University of Science and Technology of China, Hefei, Anhui, 230026, People's Republic of China. rzeng@ustc.edu.cn.|Collaborative Innovation Center of Suzhou Nano Science and Technology, Suzhou, Jiangsu, 215123, People's Republic of China. rzeng@ustc.edu.cn.
authors.forename: Raymond J
authors.initials: RJ
authors.lastname: Zeng
mesh_terms: D000693:Anaerobiosis; D001105:Archaea / Q000145:classification / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D001419:Bacteria / Q000145:classification / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D018441:Biofilms; D058448:Biota; D016000:Cluster Analysis; D019641:DNA, Archaeal / Q000737:chemistry / Q000235:genetics; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D058440:Denitrification; D059014:High-Throughput Nucleotide Sequencing; D008566:Membranes; D008697:Methane / Q000378:metabolism*; D009566:Nitrates / Q000378:metabolism; D010084:Oxidation-Reduction; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D018508:Water Purification
chemical_list: D019641:DNA, Archaeal; D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D009566:Nitrates; D012336:RNA, Ribosomal, 16S; D008697:Methane
keywords: Anaerobic ammonium oxidation (anammox); Coculture system; Denitrifying anaerobic methane oxidation (DAMO); Enrichment; Environmental factors; Hollow-fiber membrane biofilm reactor