1
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Zhang Q, Liu H, Liang S, Chen W, Tan S, Yang C, Qin S, Long K. Comparison of moving bed biofilm reactor and bio-contact oxidation reactor start-up with heterotrophic nitrification-aerobic denitrification bacteria and activated sludge inoculation under high ammonia nitrogen conditions. BIORESOURCE TECHNOLOGY 2024; 395:130408. [PMID: 38295957 DOI: 10.1016/j.biortech.2024.130408] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Revised: 01/27/2024] [Accepted: 01/28/2024] [Indexed: 02/03/2024]
Abstract
To overcome poor ammonia tolerance and removal performance of bio-contact oxidation (BCO) reactor inoculated with activated sludge for high-ammonia nitrogen (NH4+-N) chemical wastewater treatment, this study compared inoculating heterotrophic nitrification-aerobic denitrification (HN-AD) bacteria in moving bed biofilm reactor (MBBR) with activated sludge inoculation in BCO reactor under simulated high NH4+-N conditions. Results revealed that MBBR achieved faster biofilm formation (20 days vs. 100 days for BCO) with notable advantages: 27.6 % higher total nitrogen (TN) and 29.9 % higher NH4+-N removal efficiency than BCO. Microbial analysis indicated optimal enrichment of the key nitrogen removal (NR) bacterium Alcaligenes, leading to increased expression of NR enzymes hydroxylamine reductase, ensuring the superior NR efficiency of the MBBR. Additionally, functional enzymes and genes analysis speculated that the NR pathway in MBBR was: NH4+-N → NH2OH → NO3--N → NO2--N → NO → N2O → N2. This research offers a practical and theoretical foundation for extending HN-AD bacteria-inoculated MBBR processes.
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Affiliation(s)
- Qian Zhang
- College of Chemistry and Chemical Engineering, Chongqing University of Technology, Chongqing 400054, China.
| | - Huan Liu
- College of Chemistry and Chemical Engineering, Chongqing University of Technology, Chongqing 400054, China
| | - Siyu Liang
- College of Chemistry and Chemical Engineering, Chongqing University of Technology, Chongqing 400054, China
| | - Wang Chen
- College of Chemistry and Chemical Engineering, Chongqing University of Technology, Chongqing 400054, China
| | - Senwen Tan
- College of Chemistry and Chemical Engineering, Chongqing University of Technology, Chongqing 400054, China
| | - Chenxi Yang
- College of Chemistry and Chemical Engineering, Chongqing University of Technology, Chongqing 400054, China
| | - Shumin Qin
- College of Chemistry and Chemical Engineering, Chongqing University of Technology, Chongqing 400054, China
| | - Kun Long
- College of Chemistry and Chemical Engineering, Chongqing University of Technology, Chongqing 400054, China
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2
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Zhang L, Zhao H, Qin S, Hu C, Shen Y, Qu B, Bai Y, Liu B. Genome-Resolved Metagenomics and Denitrifying Strain Isolation Reveal New Insights into Microbial Denitrification in the Deep Vadose Zone. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:2323-2334. [PMID: 38267389 DOI: 10.1021/acs.est.3c06466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2024]
Abstract
The heavy use of nitrogen fertilizer in intensive agricultural areas often leads to nitrate accumulation in subsurface soil and nitrate contamination in groundwater, which poses a serious risk to public health. Denitrifying microorganisms in the subsoil convert nitrate to gaseous forms of nitrogen, thereby mitigating the leaching of nitrate into groundwater. Here, we investigated denitrifying microorganisms in the deep vadose zone of a typical intensive agricultural area in China through microcosm enrichment, genome-resolved metagenomic analysis, and denitrifying bacteria isolation. A total of 1000 metagenome-assembled genomes (MAGs) were reconstructed, resulting in 98 high-quality, dereplicated MAGs that contained denitrification genes. Among them, 32 MAGs could not be taxonomically classified at the genus or species level, indicating that a broader spectrum of taxonomic groups is involved in subsoil denitrification than previously recognized. A denitrifier isolate library was constructed by using a strategy combining high-throughput and conventional cultivation techniques. Assessment of the denitrification characteristics of both the MAGs and isolates demonstrated the dominance of truncated denitrification. Functional screening revealed the highest denitrification activity in two complete denitrifiers belonging to the genus Pseudomonas. These findings greatly expand the current knowledge of the composition and function of denitrifying microorganisms in subsoils. The constructed isolate library provided the first pool of subsoil-denitrifying microorganisms that could facilitate the development of microbe-based technologies for nitrate attenuation in groundwater.
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Affiliation(s)
- Linqi Zhang
- Key Laboratory of Agricultural Water Resources, Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Shijiazhuang 050021, China
| | - Huicheng Zhao
- Key Laboratory of Agricultural Water Resources, Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Shijiazhuang 050021, China
| | - Shuping Qin
- Key Laboratory of Agricultural Water Resources, Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Shijiazhuang 050021, China
| | - Chunsheng Hu
- Key Laboratory of Agricultural Water Resources, Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Shijiazhuang 050021, China
| | - Yanjun Shen
- Key Laboratory of Agricultural Water Resources, Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Shijiazhuang 050021, China
| | - Baoyuan Qu
- State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
- CAS-JIC Centre of Excellence for Plant and Microbial Sciences, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Yang Bai
- State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
- CAS-JIC Centre of Excellence for Plant and Microbial Sciences, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Binbin Liu
- Key Laboratory of Agricultural Water Resources, Center for Agricultural Resources Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Shijiazhuang 050021, China
- Xiong'an Institute of Innovation, Chinese Academy of Sciences, Xiong'an 071700, China
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3
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Pan D, Chen P, Yang G, Niu R, Bai Y, Cheng K, Huang G, Liu T, Li X, Li F. Fe(II) Oxidation Shaped Functional Genes and Bacteria Involved in Denitrification and Dissimilatory Nitrate Reduction to Ammonium from Different Paddy Soils. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:21156-21167. [PMID: 38064275 DOI: 10.1021/acs.est.3c06337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2023]
Abstract
Microbial nitrate reduction can drive Fe(II) oxidation in anoxic environments, affecting the nitrous oxide emission and ammonium availability. The nitrate-reducing Fe(II) oxidation usually causes severe cell encrustation via chemodenitrification and potentially inhibits bacterial activity due to the blocking effect of secondary minerals. However, it remains unclear how Fe(II) oxidation and subsequent cell encrustation affect the functional genes and bacteria for denitrification and dissimilatory nitrate reduction to ammonium (DNRA). Here, bacteria were enriched from different paddy soils with and without Fe(II) under nitrate-reducing conditions. Fe(II) addition decelerated nitrate reduction and increased NO2- accumulation, due to the rapid Fe(II) oxidation and cell encrustation in the periplasm and on the cell surface. The N2O accumulation was lower in the treatment with Fe(II) and nitrate than that in the treatment with nitrate only, although the proportions of N2O and NH4+ to the reduced NO3- were low (3.25% ∼ 6.51%) at the end of incubation regardless of Fe(II) addition. The dominant bacteria varied from soils under nitrate-reducing conditions, while Fe(II) addition shaped a similar microbial community, including Dechloromonas, Azospira, and Pseudomonas. Fe(II) addition increased the relative abundance of napAB, nirS, norBC, nosZ, and nirBD genes but decreased that of narG and nrfA, suggesting that Fe(II) oxidation favored denitrification in the periplasm and NO2--to-NH4+ reduction in the cytoplasm. Dechloromonas dominated the NO2--to-N2O reduction, while Thauera mediated the periplasmic nitrate reduction and cytoplasmic NO2--to-NH4+ during Fe(II) oxidation. However, Thauera showed much lower abundance than the dominant genera, resulting in slow nitrate reduction and limited NH4+ production. These findings provide new insights into the response of denitrification and DNRA bacteria to Fe(II) oxidation and cell encrustation in anoxic environments.
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Affiliation(s)
- Dandan Pan
- SCNU Environmental Research Institute, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety & MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou 510006, China
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Provincial Key Laboratory of Integrated Agro-Environmental Pollution Control and Management, Institute of Eco-Environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
- School of Environment, South China Normal University, Guangzhou 510006, China
| | - Pengcheng Chen
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China
| | - Guang Yang
- SCNU Environmental Research Institute, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety & MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou 510006, China
- School of Environment, South China Normal University, Guangzhou 510006, China
| | - Rumiao Niu
- SCNU Environmental Research Institute, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety & MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou 510006, China
- School of Environment, South China Normal University, Guangzhou 510006, China
| | - Yan Bai
- SCNU Environmental Research Institute, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety & MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou 510006, China
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Provincial Key Laboratory of Integrated Agro-Environmental Pollution Control and Management, Institute of Eco-Environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
- School of Environment, South China Normal University, Guangzhou 510006, China
| | - Kuan Cheng
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Provincial Key Laboratory of Integrated Agro-Environmental Pollution Control and Management, Institute of Eco-Environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
| | - Guoyong Huang
- SCNU Environmental Research Institute, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety & MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou 510006, China
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Provincial Key Laboratory of Integrated Agro-Environmental Pollution Control and Management, Institute of Eco-Environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
- School of Environment, South China Normal University, Guangzhou 510006, China
| | - Tongxu Liu
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Provincial Key Laboratory of Integrated Agro-Environmental Pollution Control and Management, Institute of Eco-Environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
| | - Xiaomin Li
- SCNU Environmental Research Institute, Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety & MOE Key Laboratory of Theoretical Chemistry of Environment, South China Normal University, Guangzhou 510006, China
- School of Environment, South China Normal University, Guangzhou 510006, China
| | - Fangbai Li
- National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China, Guangdong Provincial Key Laboratory of Integrated Agro-Environmental Pollution Control and Management, Institute of Eco-Environmental and Soil Sciences, Guangdong Academy of Sciences, Guangzhou 510650, China
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Luo Y, Luo L, Huang X, Jiang D, Wu X, Li Z. Characterization and metabolic pathway of Pseudomonas fluorescens 2P24 for highly efficient ammonium and nitrate removal. BIORESOURCE TECHNOLOGY 2023; 382:129189. [PMID: 37196744 DOI: 10.1016/j.biortech.2023.129189] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Revised: 05/11/2023] [Accepted: 05/14/2023] [Indexed: 05/19/2023]
Abstract
The ammonium and nitrate removal performance and metabolic pathways of a biocontrol strain, Pseudomonas fluorescens 2P24, were investigated. Strain 2P24 could completely remove 100 mg/L ammonium and nitrate, with removal rates of 8.27 mg/L/h and 4.29 mg/L/h, respectively. During these processes, most of the ammonium and nitrate were converted to biological nitrogen via assimilation, and only small amounts of nitrous oxide escaped. The inhibitor allylthiourea had no impact on ammonium transformation, and diethyl dithiocarbamate and sodium tungstate did not inhibit nitrate removal. Intracellular nitrate and ammonium were detectable during the nitrate and ammonium transformation process, respectively. Moreover, the nitrogen metabolism functional genes (glnK, nasA, narG, nirBD, nxrAB, nirS, nirK, and norB) were identified in the strain. All results highlighted that P. fluorescens 2P24 is capable of assimilatory and dissimilatory nitrate reduction, ammonium assimilation and oxidation, and denitrification.
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Affiliation(s)
- Yuwen Luo
- Key Laboratory of (Guangxi) Agricultural Environment and Products Safety, College of Agronomy, Guangxi University, Nanning, 530004, China
| | - Luo Luo
- Key Laboratory of (Guangxi) Agricultural Environment and Products Safety, College of Agronomy, Guangxi University, Nanning, 530004, China
| | - Xuejiao Huang
- Key Laboratory of (Guangxi) Agricultural Environment and Products Safety, College of Agronomy, Guangxi University, Nanning, 530004, China.
| | - Daihua Jiang
- Key Laboratory of (Guangxi) Agricultural Environment and Products Safety, College of Agronomy, Guangxi University, Nanning, 530004, China
| | - Xiaogang Wu
- Key Laboratory of (Guangxi) Agricultural Environment and Products Safety, College of Agronomy, Guangxi University, Nanning, 530004, China
| | - Zhenlun Li
- Chongqing Key Laboratory of Soil Multiscale Interfacial Process, Southwest University, Chongqing 400716, China
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5
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Sun Y, Su J, Ali A, Zhang S, Zheng Z, Min Y. Effect of fungal pellets on denitrifying bacteria at low carbon to nitrogen ratio: Nitrate removal, extracellular polymeric substances, and potential functions. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 847:157591. [PMID: 35901879 DOI: 10.1016/j.scitotenv.2022.157591] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Revised: 07/19/2022] [Accepted: 07/19/2022] [Indexed: 06/15/2023]
Abstract
This research aims to elucidate the effect of fungal pellets (FP) on denitrifying bacteria regarding nitrate (NO3--N) removal, extracellular polymeric substances (EPS), and potential functions at a low carbon to nitrogen (C/N) ratio. A symbiotic system of FP and denitrifying bacteria GF2 was established. The symbiotic system showed 100% NO3--N removal efficiency (4.07 mg L-1 h-1) at 6 h and enhanced electron transfer capability at C/N = 1.5. The interactions between FP and denitrifying bacteria promoted the production of polysaccharides (PS) in EPS. Both the increased PS and the PS provided by FP as well as protein and humic acid-like substances in EPS could be consumed by denitrifying bacteria. FP acted as a protector and provided habitat and nutrients for denitrifying bacteria as well as improved the ability of carbohydrate metabolism, amino metabolism, and nitrogen metabolism of denitrifying bacteria. This study provides a new perspective on the relationship between FP and denitrifying bacteria.
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Affiliation(s)
- Yi Sun
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Junfeng Su
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China.
| | - Amjad Ali
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Shuai Zhang
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Zhijie Zheng
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Yitian Min
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
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6
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Chen X, Yuan C, Zhu Y, Liu H, Chen W, Zhang Q. Bioaugmentation with Acinetobacter sp. TAC-1 to enhance nitrogen removal in swine wastewater by moving bed biofilm reactor inoculated with bacteria. BIORESOURCE TECHNOLOGY 2022; 359:127506. [PMID: 35750120 DOI: 10.1016/j.biortech.2022.127506] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Revised: 06/15/2022] [Accepted: 06/20/2022] [Indexed: 06/15/2023]
Abstract
To enhance the performance of moving bed biofilm reactor (MBBR) inoculated with heterotrophic nitrification-aerobic denitrification (HN-AD) bacteria, bioaugmentation with Acinetobacter sp. TAC-1 was firstly employed and then the treatment performance for real swine wastewater was presented in this study. Results indicated that NH4+-N and TN removal rates of bioaugmented reactor were significantly improved from 16.53 mg/L/h and 16.15 mg/L/h to 24.58 mg/L/h and 24.45 mg/L/h, respectively. The efficient removal performance (NH4+-N 95.01%, TN 86.40%) for real swine wastewater was achieved within 24 h. Microbial analysis indicated that the composition of functional bacteria varied with the introduction of Acinetobacter sp. TAC-1, especially the abundance of Acinetobacter, Paracoccus and Rhodococcus related to the nitrogen removal. Furthermore, bioaugmentation with Acinetobacter sp. TAC-1 increased abundance of enzymes and functional genes (nirS, nirK and norZ) corresponding to denitrification that may be responsible for the enhanced nitrogen removal performance.
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Affiliation(s)
- Xue Chen
- School of Chemistry and Chemical Engineering, Chongqing University of Technology, Chongqing 40054, China
| | - Chunbo Yuan
- School of Chemistry and Chemical Engineering, Chongqing University of Technology, Chongqing 40054, China
| | - Yunan Zhu
- School of Chemistry and Chemical Engineering, Chongqing University of Technology, Chongqing 40054, China
| | - Huan Liu
- School of Chemistry and Chemical Engineering, Chongqing University of Technology, Chongqing 40054, China
| | - Wang Chen
- School of Chemistry and Chemical Engineering, Chongqing University of Technology, Chongqing 40054, China
| | - Qian Zhang
- School of Chemistry and Chemical Engineering, Chongqing University of Technology, Chongqing 40054, China.
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Shi Y, Hu Y, Liang D, Wang G, Xie J, Zhu X. Enhanced denitrification of sewage via bio-microcapsules embedding heterotrophic nitrification-aerobic denitrification bacteria Acinetobacter pittii SY9 and corn cob. BIORESOURCE TECHNOLOGY 2022; 358:127260. [PMID: 35550921 DOI: 10.1016/j.biortech.2022.127260] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2022] [Revised: 04/27/2022] [Accepted: 05/01/2022] [Indexed: 06/15/2023]
Abstract
In this work, bio-microcapsules were prepared by embedding heterotrophic nitrification and aerobic denitrification (HN-AD) bacteria (Acinetobacter Pittii SY9) and corn cob. Bio-microcapsules (20 g/L of corn cob and 30% v/v suspension of strain SY9) were porous (pore size 2579.74-3725.44 nm; porosity 53.6%-79.9%). Under the appropriate conditions (C/N > 2, temperature of 20-35 ℃, rotation speed of 100-120 rpm, pH of 7-9), TN removal efficiency of bio-microcapsules reached 94.4%, and 74.0% of nitrogen was converted into N2. The results of kinetics fitting indicated that aerobic denitrification was the limiting step during HN-AD process. Bio-microcapsules could slow the carbon release of corn cob for 120 days, which ensuring high HN-AD performance even at low C/N of 2.8. Bio-microcapsule SBR could stably run for 88 days with TN removal efficiency > 90% for synthetic sewage. Bio-microcapsules embedding strain SY9 and corn cob have prospective applications for enhancing denitrification of sewage.
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Affiliation(s)
- Yunqi Shi
- School of Environment and Energy, South China University of Technology, Guangzhou Higher Education Mega Centre, Guangzhou 510006, China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, South China University of Technology, Guangzhou Higher Education Mega Centre, Guangzhou 510006, China
| | - Yongyou Hu
- School of Environment and Energy, South China University of Technology, Guangzhou Higher Education Mega Centre, Guangzhou 510006, China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, South China University of Technology, Guangzhou Higher Education Mega Centre, Guangzhou 510006, China.
| | - Donghui Liang
- School of Environment and Energy, South China University of Technology, Guangzhou Higher Education Mega Centre, Guangzhou 510006, China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, South China University of Technology, Guangzhou Higher Education Mega Centre, Guangzhou 510006, China
| | - Guobin Wang
- Guangzhou Pengkai Environment Technology Co., Ltd, Guangzhou 511493, China
| | - Jieyun Xie
- Guangzhou Pengkai Environment Technology Co., Ltd, Guangzhou 511493, China
| | - Xiaoqiang Zhu
- Guangzhou Pengkai Environment Technology Co., Ltd, Guangzhou 511493, China
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8
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Chen P, Zhang F, Zhang L, Liu H, Zhang Q, Xing Z, Zhao T. Characterization of a novel salt-tolerant strain Sphingopyxis sp. CY-10 capable of heterotrophic nitrification and aerobic denitrification. BIORESOURCE TECHNOLOGY 2022; 358:127353. [PMID: 35605774 DOI: 10.1016/j.biortech.2022.127353] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Revised: 05/16/2022] [Accepted: 05/18/2022] [Indexed: 06/15/2023]
Abstract
A novel heterotrophic nitrification and aerobic denitrification (HN-AD) strain CY-10 was isolated and identified as Sphingopyxis sp. When ammonium, nitrate or nitrite was used as the sole nitrogen source (300 mg/L), the maximum nitrogen removal efficiency of strain CY-10 were 100%, 91.1% and 68.5%, respectively. The optimal salinity for ammonia nitrogen removal by strain CY-10 was in the range of 0-5%. At the salinity of 5%, a maximum nitrogen removal rate of 6.25 mg/(L·h) was realized. Metabonomics data showed that the metabolic levels of sucrose and D-tagatose increased significantly at 5% salinity condition, enabling the strain to regulate osmotic pressure and survive in high-salt environments. Functional genes were successfully amplified by quantitative PCR, and HN-AD pathway of strain CY-10 followed NH4+-N → NH2OH → NO2--N → NO → N2O → N2. These findings show that strain CY-10 has great potential in nitrogen removal treatment of saline wastewater.
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Affiliation(s)
- Peipei Chen
- School of Chemistry and Chemical Engineering, Chongqing University of Technology, Chongqing 400054, China
| | - Fupan Zhang
- School of Chemistry and Chemical Engineering, Chongqing University of Technology, Chongqing 400054, China
| | - Lijie Zhang
- School of Pharmacy and Bioengineering, Chongqing University of Technology, Chongqing 400054, China
| | - Hao Liu
- School of Chemistry and Chemical Engineering, Chongqing University of Technology, Chongqing 400054, China
| | - Qian Zhang
- School of Chemistry and Chemical Engineering, Chongqing University of Technology, Chongqing 400054, China.
| | - Zhilin Xing
- School of Chemistry and Chemical Engineering, Chongqing University of Technology, Chongqing 400054, China
| | - Tiantao Zhao
- School of Chemistry and Chemical Engineering, Chongqing University of Technology, Chongqing 400054, China
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9
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Kang Z, Li X, Li Y, Ye L, Zhang B, Zhang X, Penttinen P, Gu Y. Black Truffles Affect Quercus aliena Physiology and Root-Associated nirK- and nirS-Type Denitrifying Bacterial Communities in the Initial Stage of Inoculation. Front Microbiol 2022; 13:792568. [PMID: 35572648 PMCID: PMC9096950 DOI: 10.3389/fmicb.2022.792568] [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: 10/10/2021] [Accepted: 03/22/2022] [Indexed: 11/29/2022] Open
Abstract
Truffles (Tuber spp.) are edible ectomycorrhizal fungi with high economic value. Bacteria in ectomycorrhizosphere soils are considered to be associated with the nutrient uptake of truffles and hosts. Whether Tuber spp. inoculation can affect the growth of Quercus aliena, the ectomycorrhizosphere soil, and the rhizosphere nirK and nirS-denitrifier communities at the ectomycorrhizae formation stage is still unclear. Therefore, we inoculated Q. aliena with the black truffles Tuber melanosporum and Tuber indicum, determined the physiological activity and morphological indices of Q. aliena seedlings, analyzed the physicochemical properties of ectomycorrhizosphere soils, and applied DNA sequencing to assess the nirK and nirS- denitrifier community structure in ectomycorrhizosphere soils. Peroxidase activity was higher in the seedlings inoculated with T. melanosporum than in the T. indicum inoculation and uninoculated control treatments. The available phosphorus contents were lower and nitrate contents were higher in those with truffle inoculation, and T. melanosporum treatment differed more from the control than the T. indicum treatment. The richness of the nirK-community was highest in the T. indicum treatment and lowest in the uninoculated treatment. The differences in nirK-community composition across treatments were not statistically significant, but the nirS communities were different. The nirS-type bacteria correlated with three environmental factors (pH, available phosphorus, and nitrate contents), whereas the nirK-type bacteria were only associated with the nitrate contents. Generally, this work revealed that inoculation with Tuber spp. would change a few nutrient contents and richness of nirK-type bacteria and had little effects on growth of Q. aliena seedlings in the initial stage of inoculation. The results of this study may provide in-depth insights into the relationships between Tuber spp. and hosts, which should be taken into account when developing truffle production methods.
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Affiliation(s)
- Zongjing Kang
- Department of Microbiology, College of Resources, Sichuan Agricultural University, Chengdu, China.,Soil and Fertilizer Institute, Sichuan Academy of Agricultural Sciences, Chengdu, China
| | - Xiaolin Li
- Soil and Fertilizer Institute, Sichuan Academy of Agricultural Sciences, Chengdu, China
| | - Yan Li
- Department of Microbiology, College of Resources, Sichuan Agricultural University, Chengdu, China
| | - Lei Ye
- Soil and Fertilizer Institute, Sichuan Academy of Agricultural Sciences, Chengdu, China
| | - Bo Zhang
- Soil and Fertilizer Institute, Sichuan Academy of Agricultural Sciences, Chengdu, China
| | - Xiaoping Zhang
- Department of Microbiology, College of Resources, Sichuan Agricultural University, Chengdu, China.,Soil and Fertilizer Institute, Sichuan Academy of Agricultural Sciences, Chengdu, China
| | - Petri Penttinen
- Department of Microbiology, College of Resources, Sichuan Agricultural University, Chengdu, China.,Ecosystems and Environment Research Programme, University of Helsinki, Helsinki, Finland
| | - Yunfu Gu
- Department of Microbiology, College of Resources, Sichuan Agricultural University, Chengdu, China
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10
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Chen X, Zhang Q, Zhu Y, Zhao T. Response of rotating biological contactor started up by heterotrophic nitrification-aerobic denitrification bacteria to various C/N ratios. CHEMOSPHERE 2022; 291:133048. [PMID: 34822871 DOI: 10.1016/j.chemosphere.2021.133048] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Revised: 10/26/2021] [Accepted: 11/21/2021] [Indexed: 06/13/2023]
Abstract
To improve the low pollutant removal efficiency of traditional biological methods for treating livestock and poultry breeding wastewater under a relatively low temperature, a rotating biological contactor (RBC) inoculated with heterotrophic nitrification-aerobic denitrification (HN-AD) bacteria was designed. A quick start-up process and a well removal performance had been achieved in the novel RBC. To elucidate the anti-load shock ability of the novel RBC, the effects of C/N ratio on nitrogen removal and microbial assemblage were focused under a low temperature (12 ± 2 °C). Results showed that the highest NH4+-N and TN removal efficiency were 99.57 ± 0.31% and 68.41 ± 0.52%. Microbial diversity analysis based on high throughput sequencing technique showed that Arcobacter and Flavobacterium with an increasing relative abundance were the key to ensure high nitrogen removal efficiently at a low C/N ratio and temperature. Moreover, nitrogen transferring pathways of the novel RBC was revealed and dissimilatory nitrate reduction and denitrification were the main pathways. The excellent pollutant removal performance demonstrates that the novel RBC is a promising process to effectively treat wastewater with low C/N ratio and low temperature.
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Affiliation(s)
- Xue Chen
- School of Chemistry and Chemical Engineering, Chongqing University of Technology, Chongqing, 40054, China
| | - Qian Zhang
- School of Chemistry and Chemical Engineering, Chongqing University of Technology, Chongqing, 40054, China.
| | - Yunan Zhu
- School of Chemistry and Chemical Engineering, Chongqing University of Technology, Chongqing, 40054, China
| | - Tiantao Zhao
- School of Chemistry and Chemical Engineering, Chongqing University of Technology, Chongqing, 40054, China
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11
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Semedo M, Wittorf L, Hallin S, Song B. Differential expression of clade I and II N2O reductase genes in denitrifying Thauera linaloolentis 47LolT under different nitrogen conditions. FEMS Microbiol Lett 2021; 367:6029120. [PMID: 33296469 DOI: 10.1093/femsle/fnaa205] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Accepted: 12/07/2020] [Indexed: 01/14/2023] Open
Abstract
Nitrous oxide (N2O) is a potent greenhouse gas and its reduction to dinitrogen gas by the N2O reductase (encoded by the nosZ gene) is the only known biological N2O sink. Within the nosZ phylogeny there are two major clades (I and II), which seem to have different ecological niches. However, physiological differences of nosZI and nosZII expression that may impact emissions of N2O are not well understood. Here, we evaluated the differential expression of nosZI and nosZII, both present in Thauera linaloolentis strain 47LolT, in response to N2O concentration and the presence of the competing electron acceptor nitrate (NO3-). Different N2O levels had a negligible effect on the expression of both nosZ clades. Interestingly, nosZII expression was strongly upregulated in the absence of NO3-, while nosZI expression remained constant across the conditions tested. Thus, NO3- possibly inhibited nosZII expression, which suggests that N2O mitigation mediated by nosZII can be restricted due to the presence of NO3- in the environment. This is the first study demonstrating differential expression of nosZI and nosZII genes under the same physiological conditions and their implications for N2O emission under varying environmental conditions in terms of NO3- availability.
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Affiliation(s)
- Miguel Semedo
- Department of Biological Sciences, Virginia Institute of Marine Science, College of William & Mary, P.O. Box 1346, Gloucester Point, Virginia 23062, USA
| | - Lea Wittorf
- Department of Forest Mycology and Plant Pathology, Swedish University of Agricultural Sciences, Box 7025, 750 07 Uppsala, Sweden, Sweden
| | - Sara Hallin
- Department of Forest Mycology and Plant Pathology, Swedish University of Agricultural Sciences, Box 7025, 750 07 Uppsala, Sweden, Sweden
| | - Bongkeun Song
- Department of Biological Sciences, Virginia Institute of Marine Science, College of William & Mary, P.O. Box 1346, Gloucester Point, Virginia 23062, USA
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12
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Durand S, Guillier M. Transcriptional and Post-transcriptional Control of the Nitrate Respiration in Bacteria. Front Mol Biosci 2021; 8:667758. [PMID: 34026838 PMCID: PMC8139620 DOI: 10.3389/fmolb.2021.667758] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2021] [Accepted: 03/29/2021] [Indexed: 12/02/2022] Open
Abstract
In oxygen (O2) limiting environments, numerous aerobic bacteria have the ability to shift from aerobic to anaerobic respiration to release energy. This process requires alternative electron acceptor to replace O2 such as nitrate (NO3 -), which has the next best reduction potential after O2. Depending on the organism, nitrate respiration involves different enzymes to convert NO3 - to ammonium (NH4 +) or dinitrogen (N2). The expression of these enzymes is tightly controlled by transcription factors (TFs). More recently, bacterial small regulatory RNAs (sRNAs), which are important regulators of the rapid adaptation of microorganisms to extremely diverse environments, have also been shown to control the expression of genes encoding enzymes or TFs related to nitrate respiration. In turn, these TFs control the synthesis of multiple sRNAs. These results suggest that sRNAs play a central role in the control of these metabolic pathways. Here we review the complex interplay between the transcriptional and the post-transcriptional regulators to efficiently control the respiration on nitrate.
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Affiliation(s)
- Sylvain Durand
- CNRS, UMR 8261, Université de Paris, Institut de Biologie Physico-Chimique, Paris, France
| | - Maude Guillier
- CNRS, UMR 8261, Université de Paris, Institut de Biologie Physico-Chimique, Paris, France
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13
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Wang L, Shao Z. Aerobic Denitrification and Heterotrophic Sulfur Oxidation in the Genus Halomonas Revealed by Six Novel Species Characterizations and Genome-Based Analysis. Front Microbiol 2021; 12:652766. [PMID: 33815342 PMCID: PMC8014003 DOI: 10.3389/fmicb.2021.652766] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Accepted: 02/09/2021] [Indexed: 11/16/2022] Open
Abstract
Bacteria of Halomonas are widely distributed in various environments and play a substantial role in the nutrient cycle. In this report, 14 strains capable of aerobic denitrification and heterotrophic sulfur oxidation were isolated from different habitats. Based on the phenotypic, genotypic, and chemotaxonomic analyses, these strains were considered to represent six novel species of the genus Halomonas, for which the names Halomonas zhangzhouensis sp. nov. type strain CXT3-11T ( = MCCC 1A11036T = KCTC 72087T), Halomonas aerodenitrificans sp. nov. CYD-9T ( = MCCC 1A11058T = KCTC 72088T), Halomonas sulfidoxydans sp. nov. CYN-1-2T ( = MCCC 1A11059T = KCTC 72089T), Halomonas ethanolica sp. nov. CYT3-1-1T ( = MCCC 1A11081T = KCTC 72090T), Halomonas sulfidivorans sp. nov. NLG_F1ET ( = MCCC 1A13718T = KCTC 72091T), and Halomonas tianxiuensis sp. nov. BC-M4-5T ( = MCCC 1A14433T = KCTC 72092T) are proposed. Intriguingly, they formed a unique group with 11 other species designated as the "H. desiderata group." To better understand their featured metabolisms, genes involved in denitrification and sulfur oxidation were analyzed, along with 193 other available genomes of the whole genus. Consistently, complete denitrification pathways were confirmed in the "H. desiderata group," in which napA, narG, nirS, norB, and nosZ genes coexist. Their nitrite reductase NirS formed a unique evolutionary lineage, distinguished from other denitrifiers in Halomonas. In addition, diverse occurrence patterns of denitrification genes were also observed in different phylogenetic clades of Halomonas. With respect to sulfur oxidation, fccAB genes involved in sulfide oxidation commonly exist in the "H. desiderata group," while sqr genes are diverse and can be found in more species; sqr genes co-occurred with fccAB in eight strains of this study, contributing to more active sulfide oxidation. Besides, the tsdA gene, which encodes an enzyme that oxidizes thiosulfate to tetrathionate, is ubiquitous in the genus Halomonas. The widespread presence of sqr/fccAB, pdo, and tsdA in Halomonas suggests that many Halomonas spp. can act as heterotrophic sulfur oxidizers. These results provide comprehensive insights into the potential of denitrification and sulfur oxidation in the whole genus of Halomonas. With regard to the global distribution of Halomonas, this report implies their unneglectable role in the biogeochemical cycle.
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Affiliation(s)
- Liping Wang
- School of Environment, Harbin Institute of Technology, Harbin, China
- Key Laboratory of Marine Genetic Resources, Third Institute of Oceanography, Ministry of Natural Resources, State Key Laboratory Breeding Base of Marine Genetic Resources, Fujian Key Laboratory of Marine Genetic Resources, Xiamen, China
| | - Zongze Shao
- School of Environment, Harbin Institute of Technology, Harbin, China
- Key Laboratory of Marine Genetic Resources, Third Institute of Oceanography, Ministry of Natural Resources, State Key Laboratory Breeding Base of Marine Genetic Resources, Fujian Key Laboratory of Marine Genetic Resources, Xiamen, China
- Laboratory for Marine Biology and Biotechnology, Pilot National Laboratory for Marine Science and Technology, Qingdao, China
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14
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Isolation and Characterization of an Aerobic Denitrifier Bacillus sp. SC16 from an Intensive Aquaculture Pond. WATER 2020. [DOI: 10.3390/w12123559] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Overloading of ammonia and nitrite nitrogen in aquaculture can result in toxicity to aquatic animals. In order to eliminate the hazardous substances, a highly efficient denitrifying bacterium, Bacillus sp. SC16, was identified in a fishery pond and isolated subsequently. The strain SC16 could remove nitrate up to 97%, ammonia up to 36.6%, and nitrite up to 99.99% when incubated with nitrate at an initial concentration of 306.9 mg·L−1 for 72 h, ammonia at 165.49 mg·L−1 for 48 h, and nitrite at 200 mg·L−1 for 24 h under aerobic conditions. The nitrite reductase gene was identified as the nirK gene. The transcriptional levels of the nirK gene in strain SC16 incubated with ammonia, nitrate, and nitrite showed similar expression patterns. When the strain SC16 was used to treat the aquaculture water, the concentration of ammonia decreased significantly, from 8.35 mg·L−1 to 4.56 mg·L−1, and there was almost no accumulation of nitrite by the end of experiment. Therefore, the results indicated that Bacillus sp. SC16 could be a promising candidate for aquaculture water treatment.
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15
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Martin-Pozas T, Sanchez-Moral S, Cuezva S, Jurado V, Saiz-Jimenez C, Perez-Lopez R, Carrey R, Otero N, Giesemann A, Well R, Calaforra JM, Fernandez-Cortes A. Biologically mediated release of endogenous N 2O and NO 2 gases in a hydrothermal, hypoxic subterranean environment. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 747:141218. [PMID: 32777502 DOI: 10.1016/j.scitotenv.2020.141218] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 07/17/2020] [Accepted: 07/22/2020] [Indexed: 06/11/2023]
Abstract
The migration of geogenic gases in continental areas with geothermal activity and active faults is an important process releasing greenhouse gases (GHG) to the lower troposphere. In this respect, caves in hypogenic environments are natural laboratories to study the compositional evolution of deep-endogenous fluids through the Critical Zone. Vapour Cave (Alhama, Murcia, Spain) is a hypogenic cave formed by the upwelling of hydrothermal CO2-rich fluids. Anomalous concentrations of N2O and NO2 were registered in the cave's subterranean atmosphere, averaging ten and five times the typical atmospheric backgrounds, respectively. We characterised the thermal conditions, gaseous compositions, sediments, and microbial communities at different depths in the cave. We did so to understand the relation between N-cycling microbial groups and the production and transformation of nitrogenous gases, as well as their coupled evolution with CO2 and CH4 during their migration through the Critical Zone to the lower troposphere. Our results showed an evident vertical stratification of selected microbial groups (Archaea and Bacteria) depending on the environmental parameters, including O2, temperature, and GHG concentration. Both the N2O isotope ratios and the predicted ecological functions of bacterial and archaeal communities suggest that N2O and NO2 emissions mainly depend on the nitrification by ammonia-oxidising microorganisms. Denitrification and abiotic reactions of the reactive intermediates NH2OH, NO, and NO2- are also plausible according to the results of the phylogenetic analyses of the microbial communities. Nitrite-dependent anaerobic methane oxidation by denitrifying methanotrophs of the NC10 phylum was also identified as a post-genetic process during migration of this gas to the surface. To the best of our knowledge, our report provides, for the first time, evidence of a niche densely populated by Micrarchaeia, which represents more than 50% of the total archaeal abundance. This raises many questions on the metabolic behaviour of this and other archaeal phyla.
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Affiliation(s)
- Tamara Martin-Pozas
- Department of Geology, National Museum of Natural Sciences (MNCN-CSIC), 28006 Madrid, Spain.
| | - Sergio Sanchez-Moral
- Department of Geology, National Museum of Natural Sciences (MNCN-CSIC), 28006 Madrid, Spain.
| | - Soledad Cuezva
- Plants and Ecosystems, Department of Biology, University of Antwerp, 2610 Wilrijk, Belgium.
| | - Valme Jurado
- Department of Agrochemistry, Environmental Microbiology and Soil Conservation, Institute of Natural Resources and Agricultural Biology (IRNAS-CSIC), 41012 Seville, Spain.
| | - Cesareo Saiz-Jimenez
- Department of Agrochemistry, Environmental Microbiology and Soil Conservation, Institute of Natural Resources and Agricultural Biology (IRNAS-CSIC), 41012 Seville, Spain.
| | - Raul Perez-Lopez
- Geological Hazard Division, Geological Survey of Spain (IGME), 28003 Madrid, Spain.
| | - Raul Carrey
- Grup MAiMA, SGR Mineralogia Aplicada, Geoquímica i Geomicrobiologia, Departament de Mineralogia, Petrologia i Geologia Aplicada, Facultat de Ciències de la Terra, Universitat de Barcelona (UB), 08028 Barcelona, Spain; Institut de Recerca de l'Aigua (IdRA), UB, 08001 Barcelona, Spain.
| | - Neus Otero
- Grup MAiMA, SGR Mineralogia Aplicada, Geoquímica i Geomicrobiologia, Departament de Mineralogia, Petrologia i Geologia Aplicada, Facultat de Ciències de la Terra, Universitat de Barcelona (UB), 08028 Barcelona, Spain; Institut de Recerca de l'Aigua (IdRA), UB, 08001 Barcelona, Spain.
| | - Anette Giesemann
- Thünen Institute of Climate-Smart Agriculture, Federal Research Institute for Rural Areas, Forestry and Fisheries, 38116 Braunschweig, Germany.
| | - Reinhard Well
- Thünen Institute of Climate-Smart Agriculture, Federal Research Institute for Rural Areas, Forestry and Fisheries, 38116 Braunschweig, Germany.
| | - Jose M Calaforra
- Department of Biology and Geology, University of Almeria, 04120 Almeria, Spain.
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16
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Goberna M, Donat S, Pérez-Valera E, Hallin S, Verdú M. nir gene-based co-occurrence patterns reveal assembly mechanisms of soil denitrifiers in response to fire. Environ Microbiol 2020; 23:239-251. [PMID: 33118311 DOI: 10.1111/1462-2920.15298] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Revised: 10/23/2020] [Accepted: 10/26/2020] [Indexed: 01/25/2023]
Abstract
Denitrification causes nitrogen losses from terrestrial ecosystems. The magnitude of nitrogen loss depends on the prevalence of denitrifiers, which show ecological differences if they harbour nirS or nirK genes encoding nitrite reductases with the same biological function. Thus, it is relevant to understand the mechanisms of co-existence of denitrifiers, including their response to environmental filters and competition due to niche similarities. We propose a framework to analyse the co-existence of denitrifiers across multiple assemblages by using nir gene-based co-occurrence networks. We applied it in Mediterranean soils before and during 1 year after an experimental fire. Burning did not modify nir community structure, but significantly impacted co-occurrence patterns. Bacteria with the same nir co-occurred in space, and those with different nir excluded each other, reflecting niche requirements: nirS abundance responded to nitrate and salinity, whereas nirK to iron content. Prior to fire, mutual exclusion between bacteria with the same nir suggested competition due to niche similarities. Burning provoked an immediate rise in mineral nitrogen and erased the signals of competition, which emerged again within days as nir abundances peaked. nir co-occurrence patterns can help infer the assembly mechanisms of denitrifying communities, which control nitrogen losses in the face of ecological disturbance.
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Affiliation(s)
- Marta Goberna
- Department of Environment and Agronomy, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Madrid, Spain
| | - Santiago Donat
- Department of Ecology, Centro de Investigaciones sobre Desertificación (CIDE - CSIC), Valencia, Spain
| | - Eduardo Pérez-Valera
- Department of Ecology, Centro de Investigaciones sobre Desertificación (CIDE - CSIC), Valencia, Spain.,Biology Centre of the Czech Academy of Sciences, Institute of Soil Biology, České Budějovice, Czech Republic
| | - Sara Hallin
- Department of Forest Mycology and Plant Pathology, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Miguel Verdú
- Department of Ecology, Centro de Investigaciones sobre Desertificación (CIDE - CSIC), Valencia, Spain
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17
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Huang R, Zeng J, Zhao D, Yong B, Yu Z. Co-association of Two nir Denitrifiers Under the Influence of Emergent Macrophytes. MICROBIAL ECOLOGY 2020; 80:809-821. [PMID: 32577778 DOI: 10.1007/s00248-020-01545-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Accepted: 06/15/2020] [Indexed: 06/11/2023]
Abstract
Diverse microorganisms perform similar metabolic process in biogeochemical cycles, whereas they are found of highly genomic differentiation. Biotic interactions should be considered in any community survey of these functional groups, as they contribute to community assembly and ultimately alter ecosystem properties. Current knowledge has mainly been achieved based on functional community characterized by a single gene using co-occurrence network analysis. Biotic interactions between functionally equivalent microorganisms, however, have received much less attention. Herein, we propose the nirK- and nirS-type denitrifier communities represented by these two nitrite reductase (nir)-encoding genes, as model communities to investigate the potential interactions of two nir denitrifiers. We evaluated co-occurrence patterns and co-association network structures of nir denitrifier community from an emergent macrophyte-dominated riparian zone of highly active denitrification in Lake Taihu, China. We found a more segregated pattern in combined nir communities than in individual communities. Network analyses revealed a modularized structure of associating nir denitrifiers. An increased proportion of negative associations among combined communities relative to those of individual communities indicated potential interspecific competition between nirK and nirS denitrifiers. pH and NH4+-N were the most important factors driving co-occurrence and mutual exclusion between nirK and nirS denitrifiers. We also showed the topological importance of nirK denitrifiers acting as module hubs for constructing entire association networks. We revealed previously unexplored co-association relationships between nirK and nirS denitrifiers, which were previously neglected in network analyses of individual communities. Using nir denitrifier community as a model, these findings would be helpful for us to understand the biotic interactions and mechanisms underlying how functional groups co-exist in performing biogeochemical cycles.
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Affiliation(s)
- Rui Huang
- State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, School of Earth Sciences and Engineering, Hohai University, Nanjing, 210098, China
| | - Jin Zeng
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, 210008, China.
| | - Dayong Zhao
- State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, School of Earth Sciences and Engineering, Hohai University, Nanjing, 210098, China
| | - Bin Yong
- State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, School of Earth Sciences and Engineering, Hohai University, Nanjing, 210098, China
| | - Zhongbo Yu
- State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, School of Earth Sciences and Engineering, Hohai University, Nanjing, 210098, China
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18
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Zhang Q, Chen X, Zhang Z, Luo W, Wu H, Zhang L, Zhang X, Zhao T. Performance and microbial ecology of a novel moving bed biofilm reactor process inoculated with heterotrophic nitrification-aerobic denitrification bacteria for high ammonia nitrogen wastewater treatment. BIORESOURCE TECHNOLOGY 2020; 315:123813. [PMID: 32702578 DOI: 10.1016/j.biortech.2020.123813] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2020] [Revised: 07/02/2020] [Accepted: 07/04/2020] [Indexed: 06/11/2023]
Abstract
To overcome long start-up time, poor ammonia tolerance and removal performance of traditional moving bed biofilm reactor (MBBR) inoculated with activated sludge for high-ammonia wastewater treatment, a novel MBBR based on heterotrophic nitrification-aerobic denitrification (HN-AD) was proposed. Start-up of MBBR was firstly performed via inoculated with HN-AD bacteria. Start-up time was shortened from 39 d to 15 d, NH4+ tolerance was enhanced from 200 mg/L to 1000 mg/L, and TN removal was increased from 30.4% to 80.7%. The carrier types and NH4+ concentration had significant effects on nitrogen removal and microbial ecology. When the NH4+ concentration was increased to 900 mg/L in MBBR using polyvinyl alcohol gel as carrier, the TN removal, the abundance of HN-AD bacteria Acinetobacter, Pseudomonas and Paracoccus, which played a key role in TN removal and ammonia tolerance, and the abundance of genes related to nitrogen removal were much higher than those of MBBR using kaldness.
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Affiliation(s)
- Qian Zhang
- School of Chemistry and Chemical Engineering, Chongqing University of Technology, Chongqing 40054, China
| | - Xue Chen
- School of Chemistry and Chemical Engineering, Chongqing University of Technology, Chongqing 40054, China
| | - Zhengyi Zhang
- School of Chemistry and Chemical Engineering, Chongqing University of Technology, Chongqing 40054, China
| | - Wandong Luo
- School of Chemistry and Chemical Engineering, Chongqing University of Technology, Chongqing 40054, China
| | - Heng Wu
- School of Chemistry and Chemical Engineering, Chongqing University of Technology, Chongqing 40054, China
| | - Lijie Zhang
- School of Pharmacy and Bioengineering, Chongqing University of Technology, Chongqing 400054, China
| | - Xiaoping Zhang
- School of Chemistry and Chemical Engineering, Chongqing University of Technology, Chongqing 40054, China
| | - Tiantao Zhao
- School of Chemistry and Chemical Engineering, Chongqing University of Technology, Chongqing 40054, China.
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19
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Liu RR, Tian Y, Zhou EM, Xiong MJ, Xiao M, Li WJ. Distinct Expression of the Two NO-Forming Nitrite Reductases in Thermus antranikianii DSM 12462 T Improved Environmental Adaptability. MICROBIAL ECOLOGY 2020; 80:614-626. [PMID: 32474659 DOI: 10.1007/s00248-020-01528-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Accepted: 05/14/2020] [Indexed: 05/21/2023]
Abstract
Hot spring ecosystems are analogous to some thermal environments on the early Earth and represent ideal models to understand life forms and element cycling on the early Earth. Denitrification, an important component of biogeochemical nitrogen cycle, is highly active in hot springs. Nitrite (NO2-) reduction to nitric oxide (NO) is the significant and rate-limiting pathway in denitrification and is catalyzed by two types of nitrite reductases, encoded by nirS and nirK genes. NirS and NirK were originally considered incompatible in most denitrifying organisms, although a few strains have been reported to possess both genes. Herein, we report the functional division of nirS and nirK in Thermus, a thermophilic genus widespread in thermal ecosystems. Transcriptional levels of nirS and nirK coexisting in Thermus antranikianii DSM 12462T were measured to assess the effects of nitrite, oxygen, and stimulation time. Thirty-nine Thermus strains were used to analyze the phylogeny and distribution of nirS and nirK; six representative strains were used to assess the denitrification phenotype. The results showed that both genes were actively transcribed and expressed independently in T. antranikianii DSM 12462T. Strains with both nirS and nirK had a wider range of nitrite adaptation and revealed nir-related physiological adaptations in Thermus: nirK facilitated adaptation to rapid changes and extended the adaptation range of nitrite under oxygen-limited conditions, while nirS expression was higher under oxic and relatively stable conditions.
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Affiliation(s)
- Rui-Rui Liu
- State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resources and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), School of Life Sciences, Sun Yat-Sen University, Guangzhou, 510275, People's Republic of China
| | - Ye Tian
- State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resources and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), School of Life Sciences, Sun Yat-Sen University, Guangzhou, 510275, People's Republic of China
| | - En-Min Zhou
- School of Resource Environment and Earth Science, Yunnan Institute of Geography, Yunnan University, Kunming, 650091, People's Republic of China
| | - Meng-Jie Xiong
- State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resources and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), School of Life Sciences, Sun Yat-Sen University, Guangzhou, 510275, People's Republic of China
| | - Min Xiao
- State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resources and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), School of Life Sciences, Sun Yat-Sen University, Guangzhou, 510275, People's Republic of China
| | - Wen-Jun Li
- State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resources and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), School of Life Sciences, Sun Yat-Sen University, Guangzhou, 510275, People's Republic of China.
- State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, 830011, People's Republic of China.
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20
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Wang L, Gan Y, Bainard LD, Hamel C, St-Arnaud M, Hijri M. Expression of N-cycling genes of root microbiomes provides insights for sustaining oilseed crop production. Environ Microbiol 2020; 22:4545-4556. [PMID: 32656968 DOI: 10.1111/1462-2920.15161] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Revised: 07/07/2020] [Accepted: 07/09/2020] [Indexed: 11/28/2022]
Abstract
Agricultural production is dependent on inputs of nitrogen (N) whose cycle relies on soil and crop microbiomes. Crop diversification has increased productivity; however, its impact on the expression of microbial genes involved in N-cycling pathways remains unknown. Here, we assessed N-cycling gene expression patterns in the root and rhizosphere microbiomes of five oilseed crops as influenced by three 2-year crop rotations. The first phase consisted of fallow, lentil or wheat, and the second phase consisted of one of five oilseed crops. Expression of bacterial amoA, nirK and nirS genes showed that the microbiome of Ethiopian mustard had the lowest and that of camelina the highest potential for N loss. A preceding rotation phase of lentil significantly increased the expression of nifH gene by 23% compared with wheat and improved nxrA gene expression by 51% with chemical fallow in the following oilseed crops respectively. Lentil substantially increased biological N2 fixation and reduced denitrification in the following oilseed crops. Our results also revealed that most N-cycling gene transcripts are more abundant in the microbiomes associated with roots than with the rhizosphere. The outcome of our investigation brings a new level of understanding on how crop diversification and rotation sequences are related to N-cycling in annual cropping systems.
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Affiliation(s)
- Li Wang
- Institut de Recherche en Biologie Végétale, Université de Montréal and Jardin Botanique de Montréal, Montréal, QC, H1X 2B2, Canada
| | - Yantai Gan
- Swift Current Research and Development Centre, Agriculture and Agri-Food Canada, Swift Current, SK, S9H 3X2, Canada
| | - Luke D Bainard
- Swift Current Research and Development Centre, Agriculture and Agri-Food Canada, Swift Current, SK, S9H 3X2, Canada
| | - Chantal Hamel
- Quebec Research and Development Centre, Agriculture and Agri-Food Canada, Quebec City, QC, G1V 2J3, Canada
| | - Marc St-Arnaud
- Institut de Recherche en Biologie Végétale, Université de Montréal and Jardin Botanique de Montréal, Montréal, QC, H1X 2B2, Canada
| | - Mohamed Hijri
- Institut de Recherche en Biologie Végétale, Université de Montréal and Jardin Botanique de Montréal, Montréal, QC, H1X 2B2, Canada.,AgroBiosciences, Mohammed VI Polytechnic University (UM6P), Lot 660 - Hay Moulay Rachid, Ben Guerir, 43150, Morocco
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21
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Zhang M, Li A, Yao Q, Wu Q, Zhu H. Nitrogen removal characteristics of a versatile heterotrophic nitrifying-aerobic denitrifying bacterium, Pseudomonas bauzanensis DN13-1, isolated from deep-sea sediment. BIORESOURCE TECHNOLOGY 2020; 305:122626. [PMID: 32143020 DOI: 10.1016/j.biortech.2019.122626] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Revised: 12/11/2019] [Accepted: 12/12/2019] [Indexed: 06/10/2023]
Abstract
A heterotrophic nitrifying-aerobic denitrifying bacterium isolated from deep-sea sediment was identified as Pseudomonas bauzanensis DN13-1. Nitrogen (N) removal capability and relative expression of nitrification and denitrification genes of this strain were investigated. The NO2--N, NO3--N and NH4+-N removal efficiencies were 98.82%, 65.87% and 98.89%, respectively, and strain DN13-1 could efficiently remove mixed N. Meanwhile, other inorganic N was not accumulated during these N removal processes. Genomic analysis indicated that genes nirS, norB, nosZ, nasA and putative amo were identified. The relative expression of functional genes by real-time PCR (qPCR) further confirmed nitrite, nitrate and ammonium removal pathways of strain DN13-1 under aerobic condition. Especially, the ammonium removal pathway of this strain was achieved through heterotrophic ammonium nitrification coupled with fast nitrite denitrification directly. Taken together, strain DN13-1 possesses particularity to efficiently remove N, which guarantees its promising application in aquaculture wastewater treatment.
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Affiliation(s)
- Mingxia Zhang
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Microbial Culture Collection Center (GDMCC), Guangdong Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, PR China
| | - Anzhang Li
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Microbial Culture Collection Center (GDMCC), Guangdong Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, PR China
| | - Qing Yao
- College of Horticulture, South China Agricultural University, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Guangzhou 510642, PR China
| | - Qingping Wu
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Microbial Culture Collection Center (GDMCC), Guangdong Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, PR China
| | - Honghui Zhu
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Microbial Culture Collection Center (GDMCC), Guangdong Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, PR China.
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22
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He T, Xie D, Ni J, Li Z, Li Z. Nitrous oxide produced directly from ammonium, nitrate and nitrite during nitrification and denitrification. JOURNAL OF HAZARDOUS MATERIALS 2020; 388:122114. [PMID: 31962213 DOI: 10.1016/j.jhazmat.2020.122114] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Revised: 12/16/2019] [Accepted: 01/14/2020] [Indexed: 06/10/2023]
Abstract
A hypothermia aerobic denitrifying bacterium, Pseudomonas taiwanensis strain J488, can effectively remove multiple nitrogen sources from wastewater at 15 °C. The ammonium, nitrate and nitrite removal efficiencies were 100 %, 92.61 % and 92.49 %, respectively. Strain J488 could survive with hydroxylamine as sole nitrogen source and its removal efficiency was 97.71 %. The removal efficiency of ammonium was 100 % even in the presence of the classical inhibitors of nitrification allylthiourea and diethyldithiocarbamate. These findings fundamentally changed the picture that the ammonia monooxygenase could be inhibited by the copper chelators of allylthiourea or diethyldithiocarbamate. Similarly, the nitrite removal capacity of strain J488 was not sensitive to inhibition by Pb2+, and its removal efficiency was also 100 %. Additionally, by identifying the intermediates accumulation of nitrification and denitrification, using nitrification and denitrification inhibitors, measuring enzyme activities and determining N2O concentrations, it was demonstrated that N2O could be produced directly from ammonium, nitrate and nitrite.
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Affiliation(s)
- Tengxia He
- Key Laboratory of Plant Resource Conservation and Germplasm Innovation in Mountainous Region (Ministry of Education), Collaborative Innovation Center for Mountain Ecology & Agro-Bioengineering (CICMEAB), College of Life Sciences/Institute of Agro-bioengineering, Guizhou University, Guiyang 550025, Guizhou Province, China
| | - Deti Xie
- Chongqing Key Laboratory of Soil Multiscale Interfacial Process, College of Resources and Environment, Southwest University, 400716, China
| | - Jiupai Ni
- Chongqing Key Laboratory of Soil Multiscale Interfacial Process, College of Resources and Environment, Southwest University, 400716, China
| | - Zhu Li
- Key Laboratory of Plant Resource Conservation and Germplasm Innovation in Mountainous Region (Ministry of Education), Collaborative Innovation Center for Mountain Ecology & Agro-Bioengineering (CICMEAB), College of Life Sciences/Institute of Agro-bioengineering, Guizhou University, Guiyang 550025, Guizhou Province, China
| | - Zhenlun Li
- Chongqing Key Laboratory of Soil Multiscale Interfacial Process, College of Resources and Environment, Southwest University, 400716, China.
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Jia Y, Zhou M, Chen Y, Luo J, Hu Y. Carbon selection for nitrogen degradation pathway by Stenotrophomonas maltophilia: Based on the balances of nitrogen, carbon and electron. BIORESOURCE TECHNOLOGY 2019; 294:122114. [PMID: 31520854 DOI: 10.1016/j.biortech.2019.122114] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Revised: 08/31/2019] [Accepted: 09/03/2019] [Indexed: 06/10/2023]
Abstract
A novel strain DQ01 capable of simultaneous removal of nitrate and ammonium under the aerobic condition was isolated from the landfill leachate and identified as Stenotrophomonas maltophilia. The result showed that S. maltophilia had carbon selection for the nitrogen removal pathway, and preferred to utilize carboxylate rather than carbohydrate, as carboxylate could directly participate in TCA cycle without Embden Meyerhof Parmas (EMP). Nitrogen and carbon balances confirmed that the ammonium assimilation was the main or even sole removal pathway for S. maltophilia, and carboxylate was more conducive to heterotrophic nitrification-aerobic denitrification (HN-AD) process due to the serious self-alkalization and higher reduction potential of carboxylate, which followed: NH4+ → NO2- → NO3- → NO2- → NO due to the lack of nor and nos. Meanwhile, the higher C/N and nitrate could generate a more powerful ion transport driving force to accelerate the electron transfer in the denitrifying respiratory chain.
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Affiliation(s)
- Yating Jia
- Ministry of Education Key Laboratory of Pollution Control and Ecological Remediation for Industrial Agglomeration Area, School of Environment and Energy, South China University of Technology, Guangzhou 510006, China
| | - Miaomiao Zhou
- Ministry of Education Key Laboratory of Pollution Control and Ecological Remediation for Industrial Agglomeration Area, School of Environment and Energy, South China University of Technology, Guangzhou 510006, China
| | - Yuancai Chen
- Ministry of Education Key Laboratory of Pollution Control and Ecological Remediation for Industrial Agglomeration Area, School of Environment and Energy, South China University of Technology, Guangzhou 510006, China.
| | - Jun Luo
- South China Institute of Environmental Science, Ministry of Ecology and Environment of People's Republic of China, Guangzhou 510000, China
| | - Yongyou Hu
- Ministry of Education Key Laboratory of Pollution Control and Ecological Remediation for Industrial Agglomeration Area, School of Environment and Energy, South China University of Technology, Guangzhou 510006, China
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24
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Su JF, Xue L, Huang TL, Wang Z, Wang JX. Kinetic analysis of denitrification coupled with Cd(II) removal by Cupriavidus sp. CC1 and its removal mechanism. Res Microbiol 2019; 170:214-221. [DOI: 10.1016/j.resmic.2019.05.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 04/16/2019] [Accepted: 05/03/2019] [Indexed: 10/26/2022]
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25
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Jang J, Sakai Y, Senoo K, Ishii S. Potentially Mobile Denitrification Genes Identified in Azospirillum sp. Strain TSH58. Appl Environ Microbiol 2019; 85:e02474-18. [PMID: 30413471 PMCID: PMC6328785 DOI: 10.1128/aem.02474-18] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Accepted: 11/05/2018] [Indexed: 11/20/2022] Open
Abstract
Denitrification ability is sporadically distributed among diverse bacteria, archaea, and fungi. In addition, disagreement has been found between denitrification gene phylogenies and the 16S rRNA gene phylogeny. These facts have suggested potential occurrences of horizontal gene transfer (HGT) for the denitrification genes. However, evidence of HGT has not been clearly presented thus far. In this study, we identified the sequences and the localization of the nitrite reductase genes in the genomes of 41 denitrifying Azospirillum sp. strains and searched for mobile genetic elements that contain denitrification genes. All Azospirillum sp. strains examined in this study possessed multiple replicons (4 to 11 replicons), with their sizes ranging from 7 to 1,031 kbp. Among those, the nitrite reductase gene nirK was located on large replicons (549 to 941 kbp). Genome sequencing showed that Azospirillum strains that had similar nirK sequences also shared similar nir-nor gene arrangements, especially between the TSH58, Sp7T, and Sp245 strains. In addition to the high similarity between nir-nor gene clusters among the three Azospirillum strains, a composite transposon structure was identified in the genome of strain TSH58, which contains the nir-nor gene cluster and the novel IS6 family insertion sequences (ISAz581 and ISAz582). The nirK gene within the composite transposon system was actively transcribed under denitrification-inducing conditions. Although not experimentally verified in this study, the composite transposon system containing the nir-nor gene cluster could be transferred to other cells if it is moved to a prophage region and the phage becomes activated and released outside the cells. Taken together, strain TSH58 most likely acquired its denitrification ability by HGT from closely related Azospirillum sp. denitrifiers.IMPORTANCE The evolutionary history of denitrification is complex. While the occurrence of horizontal gene transfer has been suggested for denitrification genes, most studies report circumstantial evidences, such as disagreement between denitrification gene phylogenies and the 16S rRNA gene phylogeny. Based on the comparative genome analyses of Azospirillum sp. denitrifiers, we identified denitrification genes, including nirK and norCBQD, located on a mobile genetic element in the genome of Azospirillum sp. strain TSH58. The nirK was actively transcribed under denitrification-inducing conditions. Since this gene was the sole nitrite reductase gene in strain TSH58, this strain most likely benefitted by acquiring denitrification genes via horizontal gene transfer. This finding will significantly advance our scientific knowledge regarding the ecology and evolution of denitrification.
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Affiliation(s)
- Jeonghwan Jang
- BioTechnology Institute, University of Minnesota, St. Paul, Minnesota, USA
| | - Yoriko Sakai
- Institute for Agro-Environmental Sciences, National Agriculture and Food Research Organization (NARO), Tsukuba, Japan
| | - Keishi Senoo
- Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, Japan
- Collaborative Research Institute for Innovative Microbiology, The University of Tokyo, Tokyo, Japan
| | - Satoshi Ishii
- BioTechnology Institute, University of Minnesota, St. Paul, Minnesota, USA
- Department of Soil, Water, and Climate, University of Minnesota, St. Paul, Minnesota, USA
- Microbial and Plant Genomics Institute, University of Minnesota, St. Paul, Minnesota, USA
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Lei X, Jia Y, Chen Y, Hu Y. Simultaneous nitrification and denitrification without nitrite accumulation by a novel isolated Ochrobactrum anthropic LJ81. BIORESOURCE TECHNOLOGY 2019; 272:442-450. [PMID: 30388582 DOI: 10.1016/j.biortech.2018.10.060] [Citation(s) in RCA: 74] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Revised: 10/22/2018] [Accepted: 10/23/2018] [Indexed: 06/08/2023]
Abstract
Nitrogen contaminants are widespread presence in municipal wastewater, heterotrophic nitrification and aerobic denitrification (HN-AD) bacteria have advantages of dealing with multiple nitrogen. Strain LJ81 was isolated from domestic sludge, identified as Ochrobactrum anthropic, which was oxygen-dependent and could survive in a wide range of pH values. Results showed that strain LJ81 could achieve simultaneous nitrification and denitrification (SND) under aerobic condition, whilst more than 80% of initial nitrogen was converted into gaseous nitrogen. The removal rates of ammonia increased from 3.75 to 3.85 and 5.70 mg-N L-1 h-1 by adding nitrite and nitrate, respectively, while the nitrate denitrification was the rate-limiting step of SND process. Moreover, adding chlorate could inhibit not only the cell growth slightly but also denitrification of nitrate. All results indicated that O. anthropic strain LJ81 exhibited excellent performance on nitrogen removal without nitrite accumulation under aerobic condition.
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Affiliation(s)
- Xin Lei
- Ministry of Education Key Laboratory of Pollution Control and Ecological Remediation for Industrial Agglomeration Area, School of Environment and Energy, South China University of Technology, Guangzhou 510006, China
| | - Yating Jia
- Ministry of Education Key Laboratory of Pollution Control and Ecological Remediation for Industrial Agglomeration Area, School of Environment and Energy, South China University of Technology, Guangzhou 510006, China
| | - Yuancai Chen
- Ministry of Education Key Laboratory of Pollution Control and Ecological Remediation for Industrial Agglomeration Area, School of Environment and Energy, South China University of Technology, Guangzhou 510006, China.
| | - Yongyou Hu
- Ministry of Education Key Laboratory of Pollution Control and Ecological Remediation for Industrial Agglomeration Area, School of Environment and Energy, South China University of Technology, Guangzhou 510006, China
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