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Qiu JG, Liu SJ. Dirammox (direct ammonia oxidation) to nitrogen (N 2): discovery, current status, and perspectives. Curr Opin Microbiol 2025; 83:102565. [PMID: 39662302 DOI: 10.1016/j.mib.2024.102565] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Revised: 11/18/2024] [Accepted: 11/20/2024] [Indexed: 12/13/2024]
Abstract
Microbial ammonia oxidation plays an important role in nitrogen (N2) cycling in natural and man-made systems. Heterotrophic microorganisms that oxidize ammonia were observed more than a century ago; however, the underlying molecular mechanism of ammonia oxidation is still mysterious. Dirammox (direct ammonia oxidation to N2) is a newly described heterotrophic ammonia oxidation process in which ammonia or its organic amine is oxidized into hydroxylamine and then directly converted to N2 gas without the involvement of nitrite and nitrate. As demonstrated with Alcaligenes species, the conversion of ammonia to hydroxylamine is mediated by the dnf genes, and hydroxylamine conversion to N2 is considered both a biotic and abiotic process. Dirammox is different from the N2-producing processes of nitrification-denitrification and anaerobic ammonia oxidation (anammox), in which nitrite or nitrate is involved. Here, we review the discovery of dirammox, progress toward understanding its genetics, biochemistry, physiology, and ecology, and future perspectives and directions.
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Affiliation(s)
- Ji-Guo Qiu
- Key Laboratory of Agricultural and Environmental Microbiology, Ministry of Agriculture and Rural Affairs, College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Shuang-Jiang Liu
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao 266273, China; State Key Laboratory of Microbial Resources, and Environmental Microbiology Research Center at Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China.
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2
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Seto M, Sasaki R, Ooka H, Nakamura R. Thermodynamics Underpinning the Microbial Community-Level Nitrogen Energy Metabolism. Environ Microbiol 2025; 27:e70055. [PMID: 39956108 PMCID: PMC11830459 DOI: 10.1111/1462-2920.70055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2024] [Revised: 12/29/2024] [Accepted: 01/14/2025] [Indexed: 02/18/2025]
Abstract
Nitrogen compounds often serve as crucial electron donors and acceptors in microbial energy metabolism, playing a key role in biogeochemical cycles. The energetic favorability of nitrogen oxidation-reduction (redox) reactions, driven by the thermodynamic properties of these compounds, may have shaped the evolution of microbial energy metabolism, though the extent of their influence remains unclear. This study quantitatively evaluated the similarity between energetically superior nitrogen reactions, identified from 988 theoretically plausible reactions, and the nitrogen community-level network, reconstructed as a combination of enzymatic reactions representing intracellular to interspecies-level reaction interactions. Our analysis revealed significant link overlap rates between these networks. Notably, composite enzymatic reactions aligned more closely with energetically superior reactions than individual enzymatic reactions. These findings suggest that selective pressure from the energetic favorability of redox reactions can operate primarily at the species or community level, underscoring the critical role of thermodynamics in shaping microbial metabolic networks and ecosystem functioning.
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Affiliation(s)
- Mayumi Seto
- Department of Chemistry, Biology, and Environmental SciencesNara Women's UniversityNaraJapan
| | - Risa Sasaki
- Department of Chemistry, Biology, and Environmental SciencesNara Women's UniversityNaraJapan
| | - Hideshi Ooka
- Biofunctional Catalyst Research TeamRIKEN Center for Sustainable Resource ScienceWakoSaitamaJapan
| | - Ryuhei Nakamura
- Biofunctional Catalyst Research TeamRIKEN Center for Sustainable Resource ScienceWakoSaitamaJapan
- Earth‐Life Science Institute (ELSI)Institute of Science TokyoTokyoJapan
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3
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Baumann KBL, Mazzoli A, Salazar G, Ruscheweyh HJ, Müller B, Niederdorfer R, Sunagawa S, Lever MA, Lehmann MF, Bürgmann H. Metagenomic and -transcriptomic analyses of microbial nitrogen transformation potential, and gene expression in Swiss lake sediments. ISME COMMUNICATIONS 2024; 4:ycae110. [PMID: 39411197 PMCID: PMC11476906 DOI: 10.1093/ismeco/ycae110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Revised: 08/23/2024] [Indexed: 10/19/2024]
Abstract
The global nitrogen (N) cycle has been strongly altered by anthropogenic activities, including increased input of bioavailable N into aquatic ecosystems. Freshwater sediments are hotspots with regards to the turnover and elimination of fixed N, yet the environmental controls on the microbial pathways involved in benthic N removal are not fully understood. Here, we analyze the abundance and expression of microbial genes involved in N transformations using metagenomics and -transcriptomics across sediments of 12 Swiss lakes that differ in sedimentation rates and trophic regimes. Our results indicate that microbial N loss in these sediments is primarily driven by nitrification coupled to denitrification. N-transformation gene compositions indicated three groups of lakes: agriculture-influenced lakes characterized by rapid depletion of oxidants in the sediment porewater, pristine-alpine lakes with relatively deep sedimentary penetration of oxygen and nitrate, and large, deep lakes with intermediate porewater hydrochemical properties. Sedimentary organic matter (OM) characteristics showed the strongest correlations with the community structure of microbial N-cycling communities. Most transformation pathways were expressed, but expression deviated from gene abundance and did not correlate with benthic geochemistry. Cryptic N-cycling may maintain transcriptional activity even when substrate levels are below detection. Sediments of large, deep lakes generally showed lower in-situ N gene expression than agriculture-influenced lakes, and half of the pristine-alpine lakes. This implies that prolonged OM mineralization in the water column can lead to the suppression of benthic N gene expression.
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Affiliation(s)
- Kathrin B L Baumann
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, 6047 Kastanienbaum, Switzerland
| | - Alessandra Mazzoli
- Department of Environmental Sciences, University of Basel, 4056 Basel, Switzerland
| | - Guillem Salazar
- Department of Biology, Institute of Microbiology and Swiss Institute of Bioinformatics, ETH Zurich, 8093 Zurich, Switzerland
| | - Hans-Joachim Ruscheweyh
- Department of Biology, Institute of Microbiology and Swiss Institute of Bioinformatics, ETH Zurich, 8093 Zurich, Switzerland
| | - Beat Müller
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, 6047 Kastanienbaum, Switzerland
| | - Robert Niederdorfer
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, 6047 Kastanienbaum, Switzerland
| | - Shinichi Sunagawa
- Department of Biology, Institute of Microbiology and Swiss Institute of Bioinformatics, ETH Zurich, 8093 Zurich, Switzerland
| | - Mark A Lever
- Institute of Biogeochemistry and Pollutant Dynamics, ETH Zurich, 8092 Zurich, Switzerland
- Now at Marine Science Institute, University of Texas at Austin, Port Aransas, 78373 TX, United States
| | - Moritz F Lehmann
- Department of Environmental Sciences, University of Basel, 4056 Basel, Switzerland
| | - Helmut Bürgmann
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, 6047 Kastanienbaum, Switzerland
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4
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Jiang C, Zhang S, Wang J, Xia X. Nitrous Oxide (N 2O) Emissions Decrease Significantly under Stronger Light Irradiance in Riverine Water Columns with Suspended Particles. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:19749-19759. [PMID: 37945339 DOI: 10.1021/acs.est.3c05526] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2023]
Abstract
Nitrous oxide (N2O) emissions from riverine water columns with suspended particles are important for the global N2O budget. Although sunlight is known to influence the activity of nitrogen-cycling microorganisms, its specific influence on N2O emissions in river systems remains unknown. This study analyzed the influences of light irradiance on N2O emissions in simulated oxic water columns with 15N-labeling and biological molecular techniques. Our results showed that N2O emissions were inhibited by light in the ammonium system (only 15NH4+ was added) and significantly decreased with increasing light irradiance in the nitrate system (only 15NO3- was added), despite contrasting variations in N2 emissions between these two systems. Lower N2O emission rates in the nitrate system under higher light conditions resulted from higher promotion levels of N2O reduction than N2O production. Increased N2O reduction was correlated to higher organic carbon bioavailability caused by photodegradation and greater potential for complete denitrification. Lower N2O production and higher N2O reduction were responsible for the lower N2O emissions observed in the ammonium system under light conditions. Our findings highlight the importance of sunlight in regulating N2O dynamics in riverine water columns, which should be considered in developing large-scale models for N2O processing and emissions in rivers.
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Affiliation(s)
- Chenrun Jiang
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, China
- Department of Urban Engineering, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo 113-8656, Japan
| | - Sibo Zhang
- Guangdong Provincial Key Laboratory of Water Quality Improvement and Ecological Restoration for Watersheds, School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou 510006, China
| | - Junfeng Wang
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, China
| | - Xinghui Xia
- State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, China
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Pan Y, Liu DF. Tapping the Potential of Wastewater Treatment with Direct Ammonia Oxidation (Dirammox). ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:7106-7108. [PMID: 37114903 DOI: 10.1021/acs.est.3c02342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Affiliation(s)
- Yuan Pan
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Environmental Science and Engineering, University of Science and Technology of China, Hefei 230026, China
| | - Dong-Feng Liu
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Environmental Science and Engineering, University of Science and Technology of China, Hefei 230026, China
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Wu MR, Miao LL, Liu Y, Qian XX, Hou TT, Ai GM, Yu L, Ma L, Gao XY, Qin YL, Zhu HZ, Du L, Li SY, Tian CL, Li DF, Liu ZP, Liu SJ. Identification and characterization of a novel hydroxylamine oxidase, DnfA, that catalyzes the oxidation of hydroxylamine to N 2. J Biol Chem 2022; 298:102372. [PMID: 35970391 PMCID: PMC9478400 DOI: 10.1016/j.jbc.2022.102372] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2022] [Revised: 08/09/2022] [Accepted: 08/10/2022] [Indexed: 11/30/2022] Open
Abstract
Nitrogen (N2) gas in the atmosphere is partially replenished by microbial denitrification of ammonia. Recent study has shown that Alcaligenes ammonioxydans oxidizes ammonia to dinitrogen via a process featuring the intermediate hydroxylamine, termed “Dirammox” (direct ammonia oxidation). However, the unique biochemistry of this process remains unknown. Here, we report an enzyme involved in Dirammox that catalyzes the conversion of hydroxylamine to N2. We tested previously annotated proteins involved in redox reactions, DnfA, DnfB, and DnfC, to determine their ability to catalyze the oxidation of ammonia or hydroxylamine. Our results showed that none of these proteins bound to ammonia or catalyzed its oxidation; however, we did find DnfA bound to hydroxylamine. Further experiments demonstrated that, in the presence of NADH and FAD, DnfA catalyzed the conversion of 15N-labeled hydroxylamine to 15N2. This conversion did not happen under oxygen (O2)-free conditions. Thus, we concluded that DnfA encodes a hydroxylamine oxidase. We demonstrate that DnfA is not homologous to any known hydroxylamine oxidoreductases and contains a diiron center, which was shown to be involved in catalysis via electron paramagnetic resonance experiments. Furthermore, enzyme kinetics of DnfA were assayed, revealing a Km of 92.9 ± 3.0 μM for hydroxylamine and a kcat of 0.028 ± 0.001 s−1. Finally, we show that DnfA was localized in the cytoplasm and periplasm as well as in tubular membrane invaginations in HO-1 cells. To the best of our knowledge, we conclude that DnfA is the first enzyme discovered that catalyzes oxidation of hydroxylamine to N2.
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Affiliation(s)
- Meng-Ru Wu
- State Key Laboratory of Microbial Resources and Environmental Microbiology Research Center, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China; University of Chinese Academy of Sciences, No.19(A) Yuquan Road, Shijingshan District, Beijing, China 100049
| | - Li-Li Miao
- State Key Laboratory of Microbial Resources and Environmental Microbiology Research Center, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Ying Liu
- State Key Laboratory of Microbial Resources and Environmental Microbiology Research Center, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Xin-Xin Qian
- State Key Laboratory of Microbial Resources and Environmental Microbiology Research Center, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Ting-Ting Hou
- State Key Laboratory of Microbial Resources and Environmental Microbiology Research Center, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China; University of Chinese Academy of Sciences, No.19(A) Yuquan Road, Shijingshan District, Beijing, China 100049
| | - Guo-Min Ai
- State Key Laboratory of Microbial Resources and Environmental Microbiology Research Center, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Lu Yu
- High Magnetic Field Laboratory, Chinese Academy of Sciences, 230031, Hefei, China
| | - Lan Ma
- State Key Laboratory of Microbial Resources and Environmental Microbiology Research Center, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China; University of Chinese Academy of Sciences, No.19(A) Yuquan Road, Shijingshan District, Beijing, China 100049
| | - Xi-Yan Gao
- State Key Laboratory of Microbial Resources and Environmental Microbiology Research Center, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China; University of Chinese Academy of Sciences, No.19(A) Yuquan Road, Shijingshan District, Beijing, China 100049
| | - Ya-Ling Qin
- State Key Laboratory of Microbial Resources and Environmental Microbiology Research Center, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China; University of Chinese Academy of Sciences, No.19(A) Yuquan Road, Shijingshan District, Beijing, China 100049
| | - Hai-Zhen Zhu
- State Key Laboratory of Microbial Resources and Environmental Microbiology Research Center, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Lei Du
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266273, China
| | - Sheng-Ying Li
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266273, China
| | - Chang-Lin Tian
- High Magnetic Field Laboratory, Chinese Academy of Sciences, 230031, Hefei, China; The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, and Center for BioAnalytical Chemistry, Hefei National Laboratory of Physical Science at Microscale, University of Science and Technology of China, 230026, Hefei, Anhui, China
| | - De-Feng Li
- State Key Laboratory of Microbial Resources and Environmental Microbiology Research Center, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China; University of Chinese Academy of Sciences, No.19(A) Yuquan Road, Shijingshan District, Beijing, China 100049.
| | - Zhi-Pei Liu
- State Key Laboratory of Microbial Resources and Environmental Microbiology Research Center, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China; University of Chinese Academy of Sciences, No.19(A) Yuquan Road, Shijingshan District, Beijing, China 100049.
| | - Shuang-Jiang Liu
- State Key Laboratory of Microbial Resources and Environmental Microbiology Research Center, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China; University of Chinese Academy of Sciences, No.19(A) Yuquan Road, Shijingshan District, Beijing, China 100049; State Key Laboratory of Microbial Technology, Shandong University, Qingdao, 266273, China.
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7
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Su X, Yang L, Yang K, Tang Y, Wen T, Wang Y, Rillig MC, Rohe L, Pan J, Li H, Zhu YG. Estuarine plastisphere as an overlooked source of N2O production. Nat Commun 2022; 13:3884. [PMID: 35794126 PMCID: PMC9259610 DOI: 10.1038/s41467-022-31584-x] [Citation(s) in RCA: 94] [Impact Index Per Article: 31.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Accepted: 06/22/2022] [Indexed: 12/13/2022] Open
Abstract
“Plastisphere”, microbial communities colonizing plastic debris, has sparked global concern for marine ecosystems. Microbiome inhabiting this novel human-made niche has been increasingly characterized; however, whether the plastisphere holds crucial roles in biogeochemical cycling remains largely unknown. Here we evaluate the potential of plastisphere in biotic and abiotic denitrification and nitrous oxide (N2O) production in estuaries. Biofilm formation provides anoxic conditions favoring denitrifiers. Comparing with surrounding bulk water, plastisphere exhibits a higher denitrifying activity and N2O production, suggesting an overlooked N2O source. Regardless of plastisphere and bulk water, bacterial and fungal denitrifications are the main regulators for N2O production instead of chemodenitrification. However, the contributions of bacteria and fungi in the plastisphere are different from those in bulk water, indicating a distinct N2O production pattern in the plastisphere. These findings pinpoint plastisphere as a N2O source, and provide insights into roles of the new biotope in biogeochemical cycling in the Anthropocene. The roles of marine plastisphere in global nitrogen cycling are largely unknown. Here, the authors indicate that the plastisphere could act as a potential source of N2O production, which is mainly regulated by the biotic denitrification
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Jiang C, Zhang S, Wang J, Xia X. The inhibitory effects of sunlight on nitrogen removal in riverine overlying water with suspended particles. CHEMOSPHERE 2022; 295:133941. [PMID: 35150703 DOI: 10.1016/j.chemosphere.2022.133941] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2021] [Revised: 01/30/2022] [Accepted: 02/08/2022] [Indexed: 06/14/2023]
Abstract
Overlying water with suspended particles is a hot spot for nitrogen removal in river systems. Although light exposure affects nitrogen transformations and nitrogen removal in some environments, such effects have rarely been explored and quantified in riverine overlying water. Herein, we examined the difference between dark and light conditions in the community composition and abundance of nitrogen transformation microbes in simulated overlying water by high-throughput sequencing and qPCR. Moreover, 15N-labeling techniques were used to investigate variation in nitrogen removal rates (N2 and N2O) as well as nitrification rates between dark and light conditions. We found apparent differences in the bacterial community between light and dark microcosms. The abundance of Cyanobacteria was greatly elevated in light microcosms, with the diazotroph nifH gene abundance being 7.4-fold higher in the light microcosm (P < 0.01). However, due to the vulnerability of some specifies to UV damage, the diazotroph species richness was reduced. The abundances of ammonia-oxidizing archaeal amoA, ammonia-oxidizing bacterial amoA, and denitrifying nirS genes were 80.1%, 46.3%, and 50.7% lower in the light microcosm, respectively, owing to the differential inhibition of sunlight exposure on these microbes. Both 15N-N2 and 15N-N2O were significantly produced regardless of conditions with or without light. Due to the combined effects of reduced nitrification and denitrification, as well as potentially enhanced nitrogen fixation, the accumulated amounts of 15N-N2 and 15N-N2O were 6.2% and 44.8% lower, respectively, in the light microcosm. This study quantifies the inhibitory effect of sunlight exposure on nitrogen removal in riverine overlying water and reveals the underlying mechanisms, providing insights into our understanding of nitrogen transformations in river systems.
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Affiliation(s)
- Chenrun Jiang
- School of Environment, Beijing Normal University / State Key Joint Laboratory of Environmental Simulation and Pollution Control / Key Laboratory of Water and Sediment Sciences of Ministry of Education, Beijing, 100875, China
| | - Sibo Zhang
- Guangdong Provincial Key Laboratory of Water Quality Improvement and Ecological Restoration for Watersheds, School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou, 510006, China.
| | - Junfeng Wang
- School of Environment, Beijing Normal University / State Key Joint Laboratory of Environmental Simulation and Pollution Control / Key Laboratory of Water and Sediment Sciences of Ministry of Education, Beijing, 100875, China
| | - Xinghui Xia
- School of Environment, Beijing Normal University / State Key Joint Laboratory of Environmental Simulation and Pollution Control / Key Laboratory of Water and Sediment Sciences of Ministry of Education, Beijing, 100875, China.
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9
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Zhang W, Shi M, Wang L, Li Y, Wang H, Niu L, Zhang H, Wang L. New insights into nitrogen removal potential in urban river by revealing the importance of microbial community succession on suspended particulate matter. ENVIRONMENTAL RESEARCH 2022; 204:112371. [PMID: 34774512 DOI: 10.1016/j.envres.2021.112371] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Revised: 11/07/2021] [Accepted: 11/08/2021] [Indexed: 06/13/2023]
Abstract
The importance of suspended particulate matter (SPM) in nitrogen removal from aquatic environments has been acknowledged in recent years by recognizing the role of attached microbes. However, the succession of attached microbes on suspended particles and their role in nitrogen removal under specific surface microenvironment are still unknown. In this study, the causation among characteristics of SPM, composition and diversity of particle-attached microbial communities, and abundances of nitrogen-related genes in urban rivers was firstly quantitatively established by combing spectroscopy, 16 S rRNA amplicon sequencing, absolute gene quantification and supervised integrated machine learning. SPM in urban rivers, coated with organic layers, was mainly composed of silt and clay (87.59-96.87%) with D50 (medium particle size) of 8.636-30.130 μm. In terms of material composition of SPM, primary mineral was quartz and the four most abundant elements were O, Si, C, Al. The principal functional groups on SPM were hydroxyl and amide. Furthermore, samples with low, medium and high levels of ammoxidation potential were classified into three groups, among which significant differences of microbial communities were found. Samples were also separated into three groups with low, medium and high levels of denitrification potential and significant differences occurred among groups. The particle size, content of functional groups and concentration of SPM were identified as the most significant factors related with microbial communities, playing an important role in succession of particle-attached microbes. In addition, the path model revealed the significantly positive effect of organic matter and particle size on the microbial communities and potential nitrogen removal. The content of hydroxyl and temperature were identified as the most effective predicting factors for ammoxidation potential and denitrification potential respectively by Random Forests Regression models, which had good predictive performances for potential of ammoxidation (R2 = 0.71) and denitrification (R2 = 0.61). These results provide a basis for quickly assessing the ability of nitrogen removal in urban rivers.
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Affiliation(s)
- Wenlong Zhang
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, PR China
| | - Meng Shi
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, PR China
| | - Linqiong Wang
- College of Oceanography, Hohai University, Nanjing, 210098, PR China
| | - Yi Li
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, PR China.
| | - Haolan Wang
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, PR China
| | - Lihua Niu
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, PR China
| | - Huanjun Zhang
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, PR China
| | - Longfei Wang
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, PR China
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10
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Wang W, Wang X, Shu X, Wang B, Li H, Zhang Q. Denitrification of Permeable Sand Sediment in a Headwater River Is Mainly Influenced by Water Chemistry, Rather Than Sediment Particle Size and Heterogeneity. Microorganisms 2021; 9:2202. [PMID: 34835328 PMCID: PMC8624688 DOI: 10.3390/microorganisms9112202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 10/08/2021] [Accepted: 10/19/2021] [Indexed: 12/03/2022] Open
Abstract
Sediment particle size and heterogeneity play an important role in sediment denitrification through direct and indirect effects on, for example, the material exchange rate, environmental gradients, microbial biomass, and grazing pressure. However, these effects have mostly been observed in impermeable sediments. On the other hand, the material exchange of permeable sediments is dominated by advection instead of diffusion, with the exchange or transport rates exceeding those of diffusion by two orders of magnitude relative to impermeable sediments. The impact of permeable sediment particle size and heterogeneity on denitrification remains poorly understood, especially at the millimeter scale. Here, we conducted an in situ control experiment in which we sorted sand sediment into four homogeneous-particle-sizes treatments and four heterogeneous treatments. Each treatment was deployed, in replicate, within the riffle in three different river reaches with contrasting physicochemical characteristics. After incubating for three months, sediment denitrifier communities (nirS, nirK, nosZ), denitrification gene abundances (nirS, nirK, nosZ), and denitrification rates in all treatments were measured. We found that most of the denitrifying microbes in permeable sediments were unclassified denitrifying microbes, and particle size and heterogeneity were not significantly correlated with the functional gene abundances or denitrification rates. Water chemistry was the key controlling factor for the denitrification of permeable sediments. Water NO3--N directly regulated the denitrification rate of permeable sediments, instead of indirectly regulating the denitrification rate of sediments by affecting the chemical characteristics of the sediments. Our study fills a knowledge gap of denitrification in permeable sediment in a headwater river and highlights that particle size and heterogeneity are less important for permeable sediment denitrification.
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Affiliation(s)
- Weibo Wang
- CAS Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan 430074, China; (X.S.); (H.L.)
- Center of Plant Ecology, Core Botanical Gardens, Chinese Academy of Sciences, Wuhan 430074, China
| | - Xu Wang
- College of Science, Tibet University, Lhasa 850000, China;
| | - Xiao Shu
- CAS Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan 430074, China; (X.S.); (H.L.)
| | - Baoru Wang
- Hengyang Key Laboratory of Soil Pollution Control and Remediation, Resource Environment and Safety Engineering College, University of South China, Hengyang 421001, China;
| | - Hongran Li
- CAS Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan 430074, China; (X.S.); (H.L.)
| | - Quanfa Zhang
- CAS Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan 430074, China; (X.S.); (H.L.)
- Center of Plant Ecology, Core Botanical Gardens, Chinese Academy of Sciences, Wuhan 430074, China
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11
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Tadda MA, Li C, Gouda M, Abomohra AEF, Shitu A, Ahsan A, Zhu S, Liu D. Enhancement of nitrite/ammonia removal from saline recirculating aquaculture wastewater system using moving bed bioreactor. JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING 2021; 9:105947. [DOI: 10.1016/j.jece.2021.105947] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2024]
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