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Motteran F, Varesche MBA, Lara-Martin PA. Assessment of the aerobic and anaerobic biodegradation of contaminants of emerging concern in sludge using batch reactors. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:84946-84961. [PMID: 35789461 DOI: 10.1007/s11356-022-21819-1] [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: 03/29/2022] [Accepted: 06/29/2022] [Indexed: 06/15/2023]
Abstract
This work explores the degradation of xenobiotic compounds in aerobic and anaerobic batch reactors. Different inoculums were spiked with nine emerging contaminants at nominal concentrations ranging between 1 to 2 mg/L (ibuprofen, diclofenac, naproxen, acesulfame, sucralose, aspartame, cyclamate, linear alkylbenzene sulfonates, and secondary alkyl sulfonates). Ethanol was used as co-substrate in the anaerobic reactors. We found that the kinetic decay was faster in the aerobic reactors inoculated with a Spanish (Spn) inoculum compared to a Brazilian (Brz) inoculum, resulting in rection rates for LAS and SAS of 2.67 ± 3.6 h-1 and 5.09 ± 6 h-1 for the Brz reactors, and 1.3 ± 0.1 h-1 and 1.5 ± 0.2 h-1 for the Spn reactors, respectively. There was no evidence of LAS and SAS degradation under anaerobic conditions within 72 days; nonetheless, under aerobic conditions, these surfactants were removed by both the Brz and Spn inoculums (up to 86.2 ± 9.4% and 74.3 ± 0.7%, respectively) within 10 days. The artificial sweeteners were not removed under aerobic conditions, whereas we could observe a steady decrease in the anaerobic reactors containing the Spn inoculum. Ethanol aided in the degradation of surfactants in anaerobic environments. Proteiniphilum, Paraclostridium, Arcobacter, Proteiniclasticum, Acinetobacter, Roseomonas, Aquamicrobium, Moheibacter, Leucobacter, Synergistes, Cyanobacteria, Serratia, and Desulfobulbus were the main microorganisms identified in this study.
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Affiliation(s)
- Fabricio Motteran
- Geosciences Technology Center, Department of Civil and Environmental Engineering, Environmental Sanitation Laboratory and Laboratory of Molecular Biology and Environmental Technology, Federal University of Pernambuco, Ave. Arquitetura, s/n, Cidade Universitária, Recife, PA, Zipcode 50740-550, Brazil.
| | - Maria Bernadete Amâncio Varesche
- Department of Hydraulics and Sanitation, São Carlos School of Engineering, University of São Paulo, Ave Trabalhador São-Carlense, n°. 400, São Carlos, São Paulo, Zipcode 13566-590, Brazil
| | - Pablo A Lara-Martin
- Department of Physical Chemistry, Faculty of Environmental and Marine Sciences, University of Cadiz (UCA), Campus Río San Pedro, 11510, Puerto Real (Cádiz), Andalusia, Spain
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Bhat SV, Maughan H, Cameron ADS, Yost CK. Phylogenomic analysis of the genus Delftia reveals distinct major lineages with ecological specializations. Microb Genom 2022; 8:mgen000864. [PMID: 36107145 PMCID: PMC9676026 DOI: 10.1099/mgen.0.000864] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Accepted: 06/15/2022] [Indexed: 04/01/2024] Open
Abstract
Delftia is a diverse betaproteobacterial genus with many strains having agricultural and industrial relevance, including plant-growth promotion, bioremediation of hydrocarbon-contaminated soils, and heavy metal immobilization. Delftia spp. are broadly distributed in the environment, and have been isolated from plant hosts as well as healthy and diseased animal hosts, yet the genetic basis of this ecological versatility has not been characterized. Here, we present a phylogenomic comparison of published Delftia genomes and show that the genus is divided into two well-supported clades: one 'Delftia acidovorans' clade with isolates from soils and plant rhizospheres, and a second 'Delftia lacustris and Delftia tsuruhatensis' clade with isolates from humans and sludge. The pan-genome inferred from 61 Delftia genomes contained over 28 000 genes, of which only 884 were found in all genomes. Analysis of industrially relevant functions highlighted the ecological versatility of Delftia and supported their role as generalists.
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Affiliation(s)
- Supriya V. Bhat
- Department of Biology, University of Regina, Regina, SK, Canada
- Institute for Microbial Systems and Society, University of Regina, Regina, SK, Canada
| | | | - Andrew D. S. Cameron
- Department of Biology, University of Regina, Regina, SK, Canada
- Institute for Microbial Systems and Society, University of Regina, Regina, SK, Canada
| | - Christopher K. Yost
- Department of Biology, University of Regina, Regina, SK, Canada
- Institute for Microbial Systems and Society, University of Regina, Regina, SK, Canada
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3
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Mars Brisbin M, Mitarai S, Saito MA, Alexander H. Microbiomes of bloom-forming Phaeocystis algae are stable and consistently recruited, with both symbiotic and opportunistic modes. THE ISME JOURNAL 2022; 16:2255-2264. [PMID: 35764675 PMCID: PMC9381791 DOI: 10.1038/s41396-022-01263-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Revised: 05/11/2022] [Accepted: 05/31/2022] [Indexed: 05/29/2023]
Abstract
Phaeocystis is a cosmopolitan, bloom-forming phytoplankton genus that contributes significantly to global carbon and sulfur cycles. During blooms, Phaeocystis species produce large carbon-rich colonies, creating a unique interface for bacterial interactions. While bacteria are known to interact with phytoplankton-e.g., they promote growth by producing phytohormones and vitamins-such interactions have not been shown for Phaeocystis. Therefore, we investigated the composition and function of P. globosa microbiomes. Specifically, we tested whether microbiome compositions are consistent across individual colonies from four P. globosa strains, whether similar microbiomes are re-recruited after antibiotic treatment, and how microbiomes affect P. globosa growth under limiting conditions. Results illuminated a core colonial P. globosa microbiome-including bacteria from the orders Alteromonadales, Burkholderiales, and Rhizobiales-that was re-recruited after microbiome disruption. Consistent microbiome composition and recruitment is indicative that P. globosa microbiomes are stable-state systems undergoing deterministic community assembly and suggests there are specific, beneficial interactions between Phaeocystis and bacteria. Growth experiments with axenic and nonaxenic cultures demonstrated that microbiomes allowed continued growth when B-vitamins were withheld, but that microbiomes accelerated culture collapse when nitrogen was withheld. In sum, this study reveals symbiotic and opportunistic interactions between Phaeocystis colonies and microbiome bacteria that could influence large-scale phytoplankton bloom dynamics and biogeochemical cycles.
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Affiliation(s)
- Margaret Mars Brisbin
- Marine Biophysics Unit, Okinawa Institute of Science and Technology, Okinawa, Japan.
- Marine Chemistry and Geochemistry Department, Woods Hole Oceanographic Institution, Woods Hole, MA, USA.
- Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA, USA.
| | - Satoshi Mitarai
- Marine Biophysics Unit, Okinawa Institute of Science and Technology, Okinawa, Japan
| | - Mak A Saito
- Marine Chemistry and Geochemistry Department, Woods Hole Oceanographic Institution, Woods Hole, MA, USA
| | - Harriet Alexander
- Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA, USA.
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Dang C, Wu Z, Zhang M, Li X, Sun Y, Wu R, Zheng Y, Xia Y. Microorganisms as bio-filters to mitigate greenhouse gas emissions from high-altitude permafrost revealed by nanopore-based metagenomics. IMETA 2022; 1:e24. [PMID: 38868568 PMCID: PMC10989947 DOI: 10.1002/imt2.24] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/04/2021] [Revised: 01/11/2022] [Accepted: 01/18/2022] [Indexed: 06/14/2024]
Abstract
The distinct climatic and geographical conditions make high-altitude permafrost on the Tibetan Plateau suffer more severe degradation than polar permafrost. However, the microbial responses associated with greenhouse gas production in thawing permafrost remain obscured. Here we applied nanopore-based long-read metagenomics and high-throughput RNA-seq to explore microbial functional activities within the freeze-thaw cycle in the active layers of permafrost at the Qilian Mountain. A bioinformatic framework was established to facilitate phylogenetic and functional annotation of the unassembled nanopore metagenome. By deploying this strategy, 42% more genera could be detected and 58% more genes were annotated to nitrogen and methane cycle. With the aid of such enlarged resolution, we observed vigorous aerobic methane oxidation by Methylomonas, which could serve as a bio-filter to mitigate CH4 emissions from permafrost. Such filtering effect could be further consolidated by both on-site gas phase measurement and incubation experiment that CO2 was the major form of carbon released from permafrost. Despite the increased transcriptional activities of aceticlastic methanogenesis pathways in the thawed permafrost active layer, CH4 generated during the thawing process could be effectively consumed by the microbiome. Additionally, the nitrogen metabolism in permafrost tends to be a closed cycle and active N2O consumption by the topsoil community was detected in the near-surface gas phase. Our findings reveal that although the increased thawed state facilitated the heterotrophic nitrogen and methane metabolism, effective microbial methane oxidation in the active layer could serve as a bio-filter to relieve the overall warming potentials of greenhouse gas emitted from thawed permafrost.
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Affiliation(s)
- Chenyuan Dang
- School of Environmental Science and Engineering, College of EngineeringSouthern University of Science and TechnologyShenzhenChina
- Laboratory of High‐Resolution Mass Spectrometry Technologies, Dalian Institute of Chemical PhysicsChinese Academy of Sciences (CAS)DalianChina
| | - Ziqi Wu
- School of Environmental Science and Engineering, College of EngineeringSouthern University of Science and TechnologyShenzhenChina
| | - Miao Zhang
- School of Environmental Science and Engineering, College of EngineeringSouthern University of Science and TechnologyShenzhenChina
| | - Xiang Li
- School of Environmental Science and Engineering, College of EngineeringSouthern University of Science and TechnologyShenzhenChina
- Shenzhen Key Laboratory of Marine Archaea Geo‐Omics, Department of Ocean Science and EngineeringSouthern University of Science and TechnologyShenzhenChina
| | - Yuqin Sun
- Shenzhen Key Laboratory of Marine Archaea Geo‐Omics, Department of Ocean Science and EngineeringSouthern University of Science and TechnologyShenzhenChina
- State Environmental Protection Key Laboratory of Integrated Surface Water‐Groundwater Pollution Control, School of Environmental Science and EngineeringSouthern University of Science and TechnologyShenzhenChina
| | - Ren'an Wu
- Laboratory of High‐Resolution Mass Spectrometry Technologies, Dalian Institute of Chemical PhysicsChinese Academy of Sciences (CAS)DalianChina
| | - Yan Zheng
- Shenzhen Key Laboratory of Marine Archaea Geo‐Omics, Department of Ocean Science and EngineeringSouthern University of Science and TechnologyShenzhenChina
- State Environmental Protection Key Laboratory of Integrated Surface Water‐Groundwater Pollution Control, School of Environmental Science and EngineeringSouthern University of Science and TechnologyShenzhenChina
| | - Yu Xia
- School of Environmental Science and Engineering, College of EngineeringSouthern University of Science and TechnologyShenzhenChina
- Shenzhen Key Laboratory of Marine Archaea Geo‐Omics, Department of Ocean Science and EngineeringSouthern University of Science and TechnologyShenzhenChina
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Ding R, Wu Y, Yang F, Xiao X, Li Y, Tian X, Zhao F. Degradation of low-concentration perfluorooctanoic acid via a microbial-based synergistic method: assessment of the feasibility and functional microorganisms. JOURNAL OF HAZARDOUS MATERIALS 2021; 416:125857. [PMID: 34492806 DOI: 10.1016/j.jhazmat.2021.125857] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 04/06/2021] [Accepted: 04/07/2021] [Indexed: 06/13/2023]
Abstract
Perfluorooctanoic acid (PFOA) is persistent in the environment. The activities of microorganisms alone are insufficient for the decomposition of PFOA, but microorganisms can contribute positively to the degradation of PFOA in synergistic systems. Herein, a synergistic system combining photocatalytic decay with microbial degradation of the transformation products was applied to degrade 500.0 μg L-1 PFOA. The microorganisms increased the total removed percentage by 30.7% to a final percentage of 79.7 ± 9.4% in comparison with the photocatalytic method alone. Moreover, an additional 44.2% of removed total organic carbon and additional defluorination percentage of 24.5% were obtained after the synergistic tests. The 16S RNA sequencing analysis indicated that Stenotrophomonas, Bacillus, Pseudomonas, and Brevundimonas were highly enriched in the functional microbial community, which was simultaneously shaped by photocatalysis and substances. This study found it would be feasible to use a synergistic method containing photocatalysis and a microbial community for the degradation of low-concentrations of PFOA, and the results provided a reference to modified the removal efficiency of the synergistic system by looking insight into the relationship between the functional microbial community and PFOA.
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Affiliation(s)
- Rui Ding
- College of Environmental Science and Engineering, Fujian Key Laboratory of Pollution Control & Resource Reuse, Fujian Normal University, Fuzhou, Fujian Province 350007, China; Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Yan Wu
- Public Health School, Fujian Medical University, Fuzhou, Fujian Province 350122, China
| | - Fan Yang
- Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xiaofeng Xiao
- Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yidi Li
- Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xiaochun Tian
- Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Feng Zhao
- Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China.
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The gut microbiota composition of Trichoplusia ni is altered by diet and may influence its polyphagous behavior. Sci Rep 2021; 11:5786. [PMID: 33707556 PMCID: PMC7970945 DOI: 10.1038/s41598-021-85057-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Accepted: 02/15/2021] [Indexed: 12/25/2022] Open
Abstract
Insects are known plant pests, and some of them such as Trichoplusia ni feed on a variety of crops. In this study, Trichoplusia ni was fed distinct diets of leaves of Arabidopsis thaliana or Solanum lycopersicum as well as an artificial diet. After four generations, the microbial composition of the insect gut was evaluated to determine if the diet influenced the structure and function of the microbial communities. The population fed with A. thaliana had higher proportions of Shinella, Terribacillus and Propionibacterium, and these genera are known to have tolerance to glucosinolate activity, which is produced by A. thaliana to deter insects. The population fed with S. lycopersicum expressed increased relative abundances of the Agrobacterium and Rhizobium genera. These microbial members can degrade alkaloids, which are produced by S. lycopersicum. All five of these genera were also present in the respective leaves of either A. thaliana or S. lycopersicum, suggesting that these microbes are acquired by the insects from the diet itself. This study describes a potential mechanism used by generalist insects to become habituated to their available diet based on acquisition of phytochemical degrading gut bacteria.
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Evans JS, Erwin PM, Sihaloho HF, López‐Legentil S. Cryptic genetic lineages of a colonial ascidian host distinct microbiomes. ZOOL SCR 2021. [DOI: 10.1111/zsc.12482] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- James S. Evans
- Department of Biology & Marine Biology Center for Marine Science University of North Carolina Wilmington Wilmington NC USA
| | - Patrick M. Erwin
- Department of Biology & Marine Biology Center for Marine Science University of North Carolina Wilmington Wilmington NC USA
| | - Hendra F. Sihaloho
- Department of Biology & Marine Biology Center for Marine Science University of North Carolina Wilmington Wilmington NC USA
| | - Susanna López‐Legentil
- Department of Biology & Marine Biology Center for Marine Science University of North Carolina Wilmington Wilmington NC USA
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Ren J, Wang Z, Deng L, Niu D, Fan B, Huhe T, Li Z, Zhang J, Li C. Biodegradation of erythromycin by Delftia lacustris RJJ-61 and characterization of its erythromycin esterase. J Basic Microbiol 2020; 61:55-62. [PMID: 33332633 DOI: 10.1002/jobm.202000613] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Revised: 12/01/2020] [Accepted: 12/05/2020] [Indexed: 11/06/2022]
Abstract
The residual erythromycin in fermentation waste can pollute the environment and threaten human health. However, there are no effective approaches to remedy this issue. In this study, an erythromycin-degrading bacterium named RJJ-61 was isolated and identified as a strain of Delftia lacustris based on morphological and phylogenetic analyses. The degradation ability of this strain was also evaluated; it could degrade 45.18% of erythromycin at 35°C in 120 h. Furthermore, the key degradation gene ereA was cloned from strain RJJ-61 and expressed in Escherichia coli BL21; the molecular weight of the expressed protein was ~45 kDa. The enzyme activity of EreA was 108.0 mU ml-1 at 35°C and pH 7.0. Finally, the EreA protein was used to degrade erythromycin from mycelial dregs and 50% diluted solution, and the removal rates in them were 41.42% and 69.78%, respectively. In summary, D. lacustris RJJ-61 is a novel erythromycin-degrading strain that has great potential to remove erythromycin pollutants from the environment.
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Affiliation(s)
- Jianjun Ren
- Institute of Urban and Rural Mining, Changzhou University, Changzhou, China.,National-Local Joint Engineering Research Center for Biomass Refining and High-Quality Utilization, Changzhou University, Changzhou, China
| | - Zhenzhu Wang
- Institute of Urban and Rural Mining, Changzhou University, Changzhou, China.,National-Local Joint Engineering Research Center for Biomass Refining and High-Quality Utilization, Changzhou University, Changzhou, China
| | - Liujie Deng
- Yili Chuanning Biotechnology Co., Yili, China
| | - Dongze Niu
- Institute of Urban and Rural Mining, Changzhou University, Changzhou, China.,National-Local Joint Engineering Research Center for Biomass Refining and High-Quality Utilization, Changzhou University, Changzhou, China
| | - Bo Fan
- School of Pharmaceutical Engineering and Life Science, Changzhou University, Wujin District, Changzhou, China
| | - Taoli Huhe
- Institute of Urban and Rural Mining, Changzhou University, Changzhou, China.,National-Local Joint Engineering Research Center for Biomass Refining and High-Quality Utilization, Changzhou University, Changzhou, China
| | - Zhenzhen Li
- School of Pharmaceutical Engineering and Life Science, Changzhou University, Wujin District, Changzhou, China
| | - Jin Zhang
- Hebei Cixin Environmental Technology Co., Langfang, China
| | - Chunyu Li
- Institute of Urban and Rural Mining, Changzhou University, Changzhou, China.,National-Local Joint Engineering Research Center for Biomass Refining and High-Quality Utilization, Changzhou University, Changzhou, China
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The fate of model organic pollutants; 3,5-dimethylphenol and N-phenyl-1-naphthaleneamine in Lake Naivasha wetland, Kenya. SCIENTIFIC AFRICAN 2020. [DOI: 10.1016/j.sciaf.2020.e00401] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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10
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Can Constructed Wetlands be Wildlife Refuges? A Review of Their Potential Biodiversity Conservation Value. SUSTAINABILITY 2020. [DOI: 10.3390/su12041442] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The degradation of wetland ecosystems is currently recognized as one of the main threats to global biodiversity. As a means of compensation, constructed wetlands (CWs), which are built to treat agricultural runoff and municipal wastewater, have become important for maintaining biodiversity. Here, we review studies on the relationships between CWs and their associated biodiversity published over the past three decades. In doing so, we provide an overview of how wildlife utilizes CWs, and the effects of biodiversity on pollutant transformation and removal. Beyond their primary aim (to purify various kinds of wastewater), CWs provide sub-optimal habitat for many species and, in turn, their purification function can be strongly influenced by the biodiversity that they support. However, there are some difficulties when using CWs to conserve biodiversity because some key characteristics of these engineered ecosystems vary from natural wetlands, including some fundamental ecological processes. Without proper management intervention, these features of CWs can promote biological invasion, as well as form an ‘ecological trap’ for native species. Management options, such as basin-wide integrative management and building in more natural wetland components, can partially offset these adverse impacts. Overall, the awareness of managers and the public regarding the potential value of CWs in biodiversity conservation remains superficial. More in-depth research, especially on how to balance different stakeholder values between wastewater managers and conservationists, is now required.
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Changes in bacterial diversity and catabolic gene abundance during the removal of dimethylphenol isomers in laboratory-scale constructed wetlands. Appl Microbiol Biotechnol 2018; 103:505-517. [PMID: 30415426 DOI: 10.1007/s00253-018-9479-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Revised: 10/19/2018] [Accepted: 10/23/2018] [Indexed: 10/27/2022]
Abstract
Constructed wetlands (CWs) are well-established wastewater treatment technologies and applied for bioremediation of contaminated water. Despite the optimal performance of CWs, the understanding of the bacterial processes in the rhizosphere, where mainly microbial degradation processes take place, is still limited. In the present study, laboratory-scale CWs planted with Juncus effusus and running under controlled conditions were studied in order to evaluate removal efficiency of dimethylphenols (DMPs), also in comparison to an unplanted bed. Next to removal rates, the bacterial community structure, diversity, and distribution, their correlation with physiochemical parameters, and abundance of the phenol hydroxylase gene were determined. As a result, better removal performance of DMP isomers (3,4-, 3,5-, and 2,6-DMP added as singles compounds or in mixtures) and ammonium loads, together with a higher diversity index, bacterial number, and phenol hydroxylase gene abundance in Juncus effusus CW in comparison with the non-planted CW, indicates a clear rhizosphere effect in the experimental CWs. An enhancement in the DMP removal and the recovery of the phenol hydroxylase gene were found during the fed with the DMP mixture. In addition, the shift of bacterial community in CWs was found to be DMP isomer dependent. Positive correlations were found between the bacteria harboring the phenol hydroxylase gene and communities present with 3,4-DMP and 3,5-DMP isomers, but not with the community developed with 2,6-DMP. These results indicate that CWs are highly dynamic ecosystems with rapid changes in bacterial communities harboring functional catabolic genes.
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