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Zhai Y, Guo W, Li D, Chen B, Xu X, Cao X, Zhao L. Size-dependent influences of nanoplastics on microbial consortium differentially inhibiting 2, 4-dichlorophenol biodegradation. Water Res 2024; 249:121004. [PMID: 38101052 DOI: 10.1016/j.watres.2023.121004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Revised: 11/22/2023] [Accepted: 12/08/2023] [Indexed: 12/17/2023]
Abstract
Nanoplastics (NPs), as a type of newly emerging pollutant, are ubiquitous in various environmental systems, one of which is coexistence with organic pollutants in wastewater, potentially influencing the pollutants' biodegradation. A knowledge gap exists regarding the influence of microbial consortium and NPs interactions on biodegradation efficiency. In this work, a 2,4-dichlorophenol (DCP) biodegradation experiment with presence of polystyrene nanoplastics (PS-NPs) with particle sizes of 100 nm (PS100) or 20 nm (PS20) was conducted to verify that PS-NPs had noticeable inhibitory effect on DCP biodegradation in a size-dependent manner. PS100 at 10 mg/L and 100 mg/L both prolonged the microbial stagnation compared to the control without PS-NPs; PS20 exacerbated greater, with PS20 at 100 mg/L causing a noticeable 6-day lag before the start-up of rapid DCP reduction. The ROS level increased to 1.4-fold and 1.8-fold under PS100 and PS20 exposure, respectively, while the elevated LDH under PS20 exposure indicated the mechanical damage to cell membrane by smaller NPs. PS-NPs exposure also resulted in a decrease in microbial diversity and altered the niches of microbial species, e.g., they decreased the abundance of some functional bacteria such as Brevundimonas and Comamonas, while facilitated some minor members to obtain more proliferation. A microbial network with higher complexity and less competition was induced to mediate PS-NPs stress. Functional metabolism responded differentially to PS100 and PS20 exposure. Specifically, PS100 downregulated amino acid metabolism, while PS20 stimulated certain pathways in response to more severe oxidative stress. Our findings give insights into PS-NPs environmental effects concerning microflora and biological degradation.
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Affiliation(s)
- Ying Zhai
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Wenbo Guo
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Deping Li
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Bo Chen
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Xiaoyun Xu
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Xinde Cao
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China; China-UK Low Carbon College, Shanghai Jiao Tong University, Shanghai 201306, China
| | - Ling Zhao
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China; China-UK Low Carbon College, Shanghai Jiao Tong University, Shanghai 201306, China.
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Venkatachalam J, Mohan H, Seralathan KK. Significance of Herbaspirillum sp. in biodegradation and biodetoxification of herbicides, pesticides, hydrocarbons and heavy metals - A review. Environ Res 2023; 239:117367. [PMID: 37827364 DOI: 10.1016/j.envres.2023.117367] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2023] [Revised: 10/04/2023] [Accepted: 10/09/2023] [Indexed: 10/14/2023]
Abstract
In today's industrialized world, contamination of soil and water with various substances has emerged as a pressing concern. Bioremediation, with its advantages of degradation or detoxification, non-polluting nature, and cost-effectiveness, has become a promising method due to technological advancements. Among the bioremediation agents, bacteria have been highly explored and documented as a productive organism. Recently, few studies have reported on the significance of Herbaspirillum sp., a Gram-negative bacterium, in bioremediating herbicides, pesticides, polycyclic aromatic hydrocarbons, metalloids, and heavy metals, as well as its role in augmenting phytoremediation efforts. Herbaspirillum sp. GW103 leached 66% of Cu from ore materials and significantly enhanced the phytoaccumulation of Pb and Zn in plumule and radical tissues of Zea mays L. plants. Additionally, Herbaspirillum sp. WT00C reduced Se6+ into Se0, resulting in an increased Se0 content in tea plants. Also, Herbaspirillum sp. proved effective in degrading 0.6 mM of 4-chlorophenol, 92.8% of pyrene, 77.4% of fluoranthene, and 16.4% of trifluralin from aqueous solution and soil-water system. Considering these findings, this review underscores the need for further exploration into the pathways of pollutant degradation, the enzymes pivotal in the degradation or detoxification processes, the influence of abiotic factors and pollutants on crucial gene expression, and the potential toxicity of intermediate products generated during the degradation process. This perspective reframes the numerical data to underscore the underutilized potential of Herbaspirillum sp. within the broader context of addressing a significant research gap. This shift in emphasis aligns more closely with the problem-necessity for solution-existing unexplored solution framework.
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Affiliation(s)
- Janaki Venkatachalam
- PG and Research Department of Chemistry, Sri Sarada College for Women, Salem, 636016, Tamil Nadu, India
| | - Harshavardhan Mohan
- Division of Biotechnology, Advanced Institute of Environment and Bioscience, College of Environmental and Bioresource Sciences, Jeonbuk National University, Iksan, 54596, South Korea
| | - Kamala-Kannan Seralathan
- Division of Biotechnology, Advanced Institute of Environment and Bioscience, College of Environmental and Bioresource Sciences, Jeonbuk National University, Iksan, 54596, South Korea.
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Guo Y, Gao J, Zhao Y, Liu Y, Zhao M, Li Z. Mitigating the inhibition of antibacterial agent chloroxylenol on nitrification system-The role of Rhodococcus ruber in a bioaugmentation system. J Hazard Mater 2023; 447:130758. [PMID: 36640510 DOI: 10.1016/j.jhazmat.2023.130758] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Revised: 12/19/2022] [Accepted: 01/07/2023] [Indexed: 06/17/2023]
Abstract
The chloroxylenol (PCMX) degrading strain was successfully isolated from sludge and identified as Rhodococcus ruber (R. ruber). Afterwards, a bioaugmentation system was constructed by seeding R. ruber into nitrifying sludge to fasten degradation efficiency of highly toxic PCMX from wastewater. Results showed that R. ruber presented high PCMX-degrading performance under aerobic conditions, 25 °C, pH 7.0 and inoculum sizes of 4% (v/v). These optimized conditions were used in subsequent bioaugmentation experiment. In bioaugmentation system, R. ruber could detoxify nitrifiers by degrading PCMX, and the content of polysaccharide in extracellular polymeric substances increased. The quantitative polymerase chain reaction results exhibited that the absolute abundance of 16S rRNA gene and ammonia oxidizing bacteria (AOB) slightly elevated in bioaugmentation system. After analyzing the results of high-throughput sequencing, it was found that the loaded R. ruber can colonize successfully and turn into dominant strains in sludge system. Molecular docking simulation showed that PCMX had a weaker suppressed effect on AOB than nitrite oxidizing bacteria, and R. ruber can alleviate the adverse effect. This study could provide a novel strategy for potential application in reinforcement of PCMX removal in wastewater treatment.
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Affiliation(s)
- Yi Guo
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Faculty of Environment and Life, Beijing University of Technology, Beijing 100124, China
| | - Jingfeng Gao
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Faculty of Environment and Life, Beijing University of Technology, Beijing 100124, China.
| | - Yifan Zhao
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Faculty of Environment and Life, Beijing University of Technology, Beijing 100124, China
| | - Ying Liu
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Faculty of Environment and Life, Beijing University of Technology, Beijing 100124, China
| | - Mingyan Zhao
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Faculty of Environment and Life, Beijing University of Technology, Beijing 100124, China
| | - Ziqiao Li
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Faculty of Environment and Life, Beijing University of Technology, Beijing 100124, China
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Zhang X, Huang Z, Wang D, Zhang Y, Eser BE, Gu Z, Dai R, Gao R, Guo Z. A new thermophilic extradiol dioxygenase promises biodegradation of catecholic pollutants. J Hazard Mater 2022; 422:126860. [PMID: 34399224 DOI: 10.1016/j.jhazmat.2021.126860] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2021] [Revised: 07/22/2021] [Accepted: 08/06/2021] [Indexed: 06/13/2023]
Abstract
Extradiol dioxygenases (EDOs) catalyze the meta cleavage of catechol into 2-hydroxymuconaldehyde, a critical step in the degradation of aromatic compounds in the environment. In the present work, a novel thermophilic extradiol dioxygenase from Thermomonospora curvata DSM43183 was cloned, expressed, and characterized by phylogenetic and biochemical analyses. This enzyme exhibited excellent thermo-tolerance, displaying optimal activity at 50 °C, remaining >40% activity at 70 °C. Structural modeling and molecular docking demonstrated that both active center and pocket-construction loops locate at the C-terminal domain. Site-specific mutants D285A, H205V, F301V based on a rational design were obtained to widen the entrance of substrates; resulting in significantly improved catalytic performance for all the 3 mutants. Compared to the wild-type, the mutant D285A showed remarkably improved activities with respect to the 3,4-dihydroxyphenylacetic acid, catechol, and 3-chlorocatechol, by 17.7, 6.9, and 3.7-fold, respectively. The results thus verified the effectiveness of modeling guided design; and confirmed that the C-terminal loop structure indeed plays a decisive role in determining catalytic ring-opening efficiency and substrate specificity of the enzyme. This study provided a novel thermostable dioxygenase with a broad substrate promiscuity for detoxifying environmental pollutants and provided a new thinking for further enzyme engineering of EDOs.
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Affiliation(s)
- Xiaowen Zhang
- Key Laboratory for Molecular Enzymology and Engineering, The Ministry of Education, School of life Science, Jilin University, Changchun 130021, China; Department of Biological and Chemical Engineering, Faculty of Technical Sciences, Aarhus University, Gustav Wieds Vej 10, Aarhus 8000, Denmark
| | - Zihao Huang
- Key Laboratory for Molecular Enzymology and Engineering, The Ministry of Education, School of life Science, Jilin University, Changchun 130021, China
| | - Dan Wang
- Key Laboratory for Molecular Enzymology and Engineering, The Ministry of Education, School of life Science, Jilin University, Changchun 130021, China
| | - Yan Zhang
- Department of Biological and Chemical Engineering, Faculty of Technical Sciences, Aarhus University, Gustav Wieds Vej 10, Aarhus 8000, Denmark
| | - Bekir Engin Eser
- Department of Biological and Chemical Engineering, Faculty of Technical Sciences, Aarhus University, Gustav Wieds Vej 10, Aarhus 8000, Denmark
| | - Zhenyu Gu
- Key Laboratory for Molecular Enzymology and Engineering, The Ministry of Education, School of life Science, Jilin University, Changchun 130021, China
| | - Rongrong Dai
- Department of Biological and Chemical Engineering, Faculty of Technical Sciences, Aarhus University, Gustav Wieds Vej 10, Aarhus 8000, Denmark
| | - Renjun Gao
- Key Laboratory for Molecular Enzymology and Engineering, The Ministry of Education, School of life Science, Jilin University, Changchun 130021, China.
| | - Zheng Guo
- Department of Biological and Chemical Engineering, Faculty of Technical Sciences, Aarhus University, Gustav Wieds Vej 10, Aarhus 8000, Denmark.
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Khalofah A, Kilany M, Migdadi H. Phytostimulatory Influence of Comamonas testosteroni and Silver Nanoparticles on Linum usitatissimum L. under Salinity Stress. Plants (Basel) 2021; 10:790. [PMID: 33923824 DOI: 10.3390/plants10040790] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Revised: 04/13/2021] [Accepted: 04/15/2021] [Indexed: 12/20/2022]
Abstract
They were shifting in land use increases salinity stress, significant abiotic stress affecting plant growth, limiting crop productivity. This work aimed to improve Linum usitatissimum L. (linseed) growth under salinity using Comamonas testosteroni and silver nanoparticles (AgNPs). AgNPs were fabricated exploiting Rosmarinus officinalis and monitored by U.V./Vis spectrophotometry scanning electron microscopy (SEM) and Fourier transforms infrared spectroscopy (FTIR). Photosynthetic pigments, enzymatic and nonenzymatic antioxidants of linseed were investigated under salt stress in treated and untreated plants with C. testosteroni alongside AgNPs. Our findings recorded the formation of AgNPs at 457 nm, which were globular and with a diameter of 75 nm. Notably, chlorophyll-a, b, and total chlorophyll reduction while enhanced carotenoids and anthocyanin contents were attained under salinity stress. Total dissoluble sugars, proline, and dissoluble proteins, H2O2, malondialdehyde, enzymatic and nonenzymatic antioxidants were significantly elevated in NaCl well. Combined AgNPs and C. testosteroni elevated photosynthetic pigments. Also, they led to the mounting of soluble sugars, proline, and soluble proteins. H2O2 and malondialdehyde decreased while enzymatic and nonenzymatic antioxidants increased in response to AgNPs, C. testosteroni, and their combination. Thus, AgNPs and C. testosteroni might bio-fertilizers to improve linseed crop productivity under salinity stress.
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Michalska J, Piński A, Żur J, Mrozik A. Selecting Bacteria Candidates for the Bioaugmentation of Activated Sludge to Improve the Aerobic Treatment of Landfill Leachate. Water 2020; 12:140. [DOI: 10.3390/w12010140] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
In this study, a multifaceted approach for selecting the suitable candidates for bioaugmentation of activated sludge (AS) that supports leachate treatment was used. To determine the exploitation of 10 bacterial strains isolated from the various matrices for inoculating the AS contaminated with the Kalina pond leachate (KPL), their degradative potential was analyzed along with their aptitude to synthesize compounds improving remediation of pollutants in wastewater and ability to incorporate into the AS flocs. Based on their capability to degrade aromatic compounds (primarily catechol, phenol, and cresols) at a concentration of 1 mg/mL and survive in 12.5% of the KPL, Pseudomonas putida OR45a and P. putida KB3 can be considered to be the best candidates for bioaugmentation of the AS among all of the bacteria tested. Genomic analyses of these two strains revealed the presence of the genes encoding enzymes related to the metabolism of aromatic compounds. Additionally, both microorganisms exhibited a high hydrophobic propensity (above 50%) and an ability to produce biosurfactants as well as high resistance to ammonium (above 600 µg/mL) and heavy metals (especially chromium). These properties enable the exploitation of both bacterial strains in the bioremediation of the AS contaminated with the KPL.
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Wang G, Liu Y, Wu M, Zong W, Yi X, Zhan J, Liu L, Zhou H. Coupling the phenolic oxidation capacities of a bacterial consortium and in situ-generated manganese oxides in a moving bed biofilm reactor (MBBR). Water Res 2019; 166:115047. [PMID: 31514099 DOI: 10.1016/j.watres.2019.115047] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2019] [Revised: 08/23/2019] [Accepted: 09/03/2019] [Indexed: 06/10/2023]
Abstract
Phenolic wastewater containing phenol and 4-chlorophenol pose a risk to the environment and to human health. Treating them using chemical-biological coupling method is challenging. In this study, manganese oxidizing bacteria (MnOB) were enriched in moving bed biofilm reactor (MBBR) using synthetic phenol wastewater (800 mg L-1) to facilitate in situ production of biogenic manganese oxides (BioMnOx) after 90 days of operation. Then, 4-chlorophenol (4-CP) was added to the MBBR to simulate mixed phenolic wastewater. Comparing the MBBR (R1) without feeding Mn(II) and the MBBR with BioMnOx (R2) production, R2 exhibited robust phenol and 4-CP removal performance. 16S rRNA gene sequencing was employed to determine the microbial community. Subsequently, a batch experiment demonstrated that partly purified BioMnOx does not exhibits a capacity for phenol removal, but can efficiently remove 4-CP. Interestingly, 5-chloro-2-hydroxymuconic semialdehyde was found in the products of 4-CP degradation, which was the unique product of 4-CP degradation by catechol 2,3-dioxygenase (C23O). In both reactors, only catechol 1,2-dioxygenase (C12O) activity from microbes can be detected, indicating that the existence of BioMnOx provide an alternative pathway in addition to microbe driven 4-CP degradation. Overall, MBBR based MnOB enrichment under high phenol concentration was achieved, and 4-CP/phenol removal can be accelerated by in situ-formed BioMnOx. Considering the C23O-like activity of BioMnOx, our results suggest a new coupling strategy that involves nanomaterials and a microbial consortium.
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Affiliation(s)
- Guochen Wang
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Food and Environment, Dalian University of Technology, China
| | - Yang Liu
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Food and Environment, Dalian University of Technology, China
| | - Minghuo Wu
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Food and Environment, Dalian University of Technology, China
| | - Wenjing Zong
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Food and Environment, Dalian University of Technology, China
| | - Xianliang Yi
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Food and Environment, Dalian University of Technology, China
| | - Jingjing Zhan
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Food and Environment, Dalian University of Technology, China
| | - Lifen Liu
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Food and Environment, Dalian University of Technology, China
| | - Hao Zhou
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Food and Environment, Dalian University of Technology, China.
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Vásquez Piñeros MA, Martínez-Lavanchy PM, Schmidt K, Mardones M, Heipieper HJ. Changes in bacterial diversity and catabolic gene abundance during the removal of dimethylphenol isomers in laboratory-scale constructed wetlands. Appl Microbiol Biotechnol 2019; 103:505-17. [PMID: 30415426 DOI: 10.1007/s00253-018-9479-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [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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Vásquez-Piñeros MA, Martínez-Lavanchy PM, Jehmlich N, Pieper DH, Rincón CA, Harms H, Junca H, Heipieper HJ. Delftia sp. LCW, a strain isolated from a constructed wetland shows novel properties for dimethylphenol isomers degradation. BMC Microbiol 2018; 18:108. [PMID: 30189831 PMCID: PMC6127914 DOI: 10.1186/s12866-018-1255-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Accepted: 08/30/2018] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Dimethylphenols (DMP) are toxic compounds with high environmental mobility in water and one of the main constituents of effluents from petro- and carbochemical industry. Over the last few decades, the use of constructed wetlands (CW) has been extended from domestic to industrial wastewater treatments, including petro-carbochemical effluents. In these systems, the main role during the transformation and mineralization of organic pollutants is played by microorganisms. Therefore, understanding the bacterial degradation processes of isolated strains from CWs is an important approach to further improvements of biodegradation processes in these treatment systems. RESULTS In this study, bacterial isolation from a pilot scale constructed wetland fed with phenols led to the identification of Delftia sp. LCW as a DMP degrading strain. The strain was able to use the o-xylenols 3,4-DMP and 2,3-DMP as sole carbon and energy sources. In addition, 3,4-DMP provided as a co-substrate had an effect on the transformation of other four DMP isomers. Based on the detection of the genes, proteins, and the inferred phylogenetic relationships of the detected genes with other reported functional proteins, we found that the phenol hydroxylase of Delftia sp. LCW is induced by 3,4-DMP and it is responsible for the first oxidation of the aromatic ring of 3,4-, 2,3-, 2,4-, 2,5- and 3,5-DMP. The enzyme may also catalyze both monooxygenation reactions during the degradation of benzene. Proteome data led to the identification of catechol meta cleavage pathway enzymes during the growth on ortho DMP, and validated that cleavage of the aromatic rings of 2,5- and 3,5-DMPs does not result in mineralization. In addition, the tolerance of the strain to high concentrations of DMP, especially to 3,4-DMP was higher than that of other reported microorganisms from activated sludge treating phenols. CONCLUSIONS LCW strain was able to degraded complex aromatics compounds. DMPs and benzene are reported for the first time to be degraded by a member of Delftia genus. In addition, LCW degraded DMPs with a first oxidation of the aromatic rings by a phenol hydroxylase, followed by a further meta cleavage pathway. The higher resistance to DMP toxicity, the ability to degrade and transform DMP isomers and the origin as a rhizosphere bacterium from wastewater systems, make LCW a suitable candidate to be used in bioremediation of complex DMP mixtures in CWs systems.
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Affiliation(s)
- Mónica A Vásquez-Piñeros
- Helmholtz Centre for Environmental Research - UFZ, Department of Environmental Biotechnology, Permoserstr. 15, Leipzig, Germany
| | - Paula M Martínez-Lavanchy
- Helmholtz Centre for Environmental Research - UFZ, Department of Environmental Biotechnology, Permoserstr. 15, Leipzig, Germany.,Technical University of Denmark, Research Data Management - DTU Library, Lyngby, Denmark
| | - Nico Jehmlich
- Helmholtz Centre for Environmental Research - UFZ, Department of Molecular Systems Biology, Leipzig, Germany
| | - Dietmar H Pieper
- Helmholtz Centre for Infection Research -HZI, Microbial Interaction and Processes Research Group, Braunschweig, Germany
| | - Carlos A Rincón
- Helmholtz Centre for Environmental Research - UFZ, Department of Environmental Biotechnology, Permoserstr. 15, Leipzig, Germany
| | - Hauke Harms
- Helmholtz Centre for Environmental Research - UFZ, Department of Environmental Microbiology, Leipzig, Germany
| | - Howard Junca
- Microbiomas Research Foundation, Bogotá, Colombia
| | - Hermann J Heipieper
- Helmholtz Centre for Environmental Research - UFZ, Department of Environmental Biotechnology, Permoserstr. 15, Leipzig, Germany.
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Xi L, Liu D, Wang L, Qiao N, Liu J. Catechol 2,3-dioxygenase from a new phenolic compound degraderThauerasp. K11: purification and biochemical characterization. J Basic Microbiol 2018; 58:255-262. [DOI: 10.1002/jobm.201700566] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2017] [Revised: 12/19/2017] [Accepted: 12/23/2017] [Indexed: 11/12/2022]
Affiliation(s)
- Lijun Xi
- State Key Laboratory of Heavy Oil Processing and Center for Bioengineering and Biotechnology; China University of Petroleum (East China); Qingdao P.R. China
| | - Dejian Liu
- State Key Laboratory of Heavy Oil Processing and Center for Bioengineering and Biotechnology; China University of Petroleum (East China); Qingdao P.R. China
| | - Lingling Wang
- State Key Laboratory of Heavy Oil Processing and Center for Bioengineering and Biotechnology; China University of Petroleum (East China); Qingdao P.R. China
| | - Nenghu Qiao
- State Key Laboratory of Heavy Oil Processing and Center for Bioengineering and Biotechnology; China University of Petroleum (East China); Qingdao P.R. China
| | - Jianguo Liu
- State Key Laboratory of Heavy Oil Processing and Center for Bioengineering and Biotechnology; China University of Petroleum (East China); Qingdao P.R. China
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Cho SY, Kwean OS, Yang JW, Cho W, Kwak S, Park S, Lim Y, Kim HS. Identification of the upstream 4-chlorophenol biodegradation pathway using a recombinant monooxygenase from Arthrobacter chlorophenolicus A6. Bioresour Technol 2017; 245:1800-1807. [PMID: 28522197 DOI: 10.1016/j.biortech.2017.05.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2017] [Revised: 04/28/2017] [Accepted: 05/01/2017] [Indexed: 05/06/2023]
Abstract
This study aimed to clarify the initial 4-chlorophenol (4-CP) biodegradation pathway promoted by a two-component flavin-diffusible monooxygenase (TC-FDM) consisting of CphC-I and CphB contained in Arthrobacter chlorophenolicus A6 and the decomposition function of CphC-I. The TC-FDM genes were cloned from A. chlorophenolicus A6, and the corresponding enzymes were overexpressed. Since CphB was expressed in an insoluble form, Fre, a flavin reductase obtained from Escherichia coli, was used. These enzymes were purified using Ni2+-NTA resin. It was confirmed that TC-FDM catalyzes the oxidation of 4-CP and the sequential conversion of 4-CP to benzoquinone (BQN)→hydroquinone (HQN)→HQL. This indicated that CphC-I exhibits substrate specificity for 4-CP, BQN, and HQN. The activity of CphC-I for 4-CP was 63.22U/mg-protein, and the Michaelis-Menten kinetic parameters were vmax=0.21mM/min, KM=0.19mM, and kcat/KM=0.04mM-1min-1. These results would be useful for the development of a novel biochemical treatment technology for 4-CP and phenolic hydrocarbons.
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Affiliation(s)
- Su Yeon Cho
- Environmental Engineering, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 05029, Republic of Korea
| | - Oh Sung Kwean
- Environmental Engineering, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 05029, Republic of Korea
| | - Jun Won Yang
- Environmental Engineering, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 05029, Republic of Korea
| | - Wooyoun Cho
- Environmental Engineering, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 05029, Republic of Korea
| | - Seonyeong Kwak
- Environmental Engineering, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 05029, Republic of Korea
| | - Sungyoon Park
- Environmental Engineering, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 05029, Republic of Korea
| | - Yejee Lim
- Environmental Engineering, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 05029, Republic of Korea
| | - Han S Kim
- Environmental Engineering, Konkuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul 05029, Republic of Korea.
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12
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Liang J, Peng X, Yin D, Li B, Wang D, Lin Y. Screening of a microbial consortium for highly simultaneous degradation of lignocellulose and chlorophenols. Bioresour Technol 2015; 190:381-387. [PMID: 25974352 DOI: 10.1016/j.biortech.2015.04.105] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2015] [Revised: 04/25/2015] [Accepted: 04/27/2015] [Indexed: 06/04/2023]
Abstract
In this work, spent mushroom substrates were utilized for screening a microbial consortium with highly simultaneous degradation of lignocellulose and chlorophenols. The desired microbial consortium OEM1 was gained through successive cultivation for about 50 generations and its stability of composition was verified by denaturing gradient gel electrophoresis (DGGE) during screening process. It could degrade lignocellulose and chlorophenols at around 50% and 100%, respectively, within 7days. The diversity analysis and the growth characteristics of OEM1 during degradation process were investigated by PCR-DGGE combined with clone and sequence. The results indicated that OEM1 consisted of 31 strains. Proteobacteria and Bacteroidetes were the predominant bacterial groups. The dynamic change of OEM1 illustrated that consortium community structure was effected by pH and substrate alteration and tended to be stable after 6days' cultivation. Furthermore, bacteria (11 strains) and actinomycetes (2 strains) were obtained based on plate isolation and identified via 16S rDNA sequence.
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Affiliation(s)
- Jiajin Liang
- College of Natural Resources and Environment, South China Agricultural University, Guangzhou, Guangdong 510642, PR China; State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640, PR China
| | - Xiang Peng
- College of Natural Resources and Environment, South China Agricultural University, Guangzhou, Guangdong 510642, PR China
| | - Dexing Yin
- College of Natural Resources and Environment, South China Agricultural University, Guangzhou, Guangdong 510642, PR China
| | - Beiyin Li
- College of Natural Resources and Environment, South China Agricultural University, Guangzhou, Guangdong 510642, PR China
| | - Dehan Wang
- College of Natural Resources and Environment, South China Agricultural University, Guangzhou, Guangdong 510642, PR China
| | - Yunqin Lin
- College of Natural Resources and Environment, South China Agricultural University, Guangzhou, Guangdong 510642, PR China.
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13
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Zhao B, Hua X, Wang F, Dong W, Li Z, Yang Y, Cui Z, Wang M. Biodegradation of propyzamide by Comamonas testosteroni W1 and cloning of the propyzamide hydrolase gene camH. Bioresour Technol 2015; 179:144-149. [PMID: 25541381 DOI: 10.1016/j.biortech.2014.12.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Revised: 12/02/2014] [Accepted: 12/04/2014] [Indexed: 06/04/2023]
Abstract
Propyzamide is a widely used benzamide herbicide for controlling weeds in lettuce, soybeans, cotton and other crops. An efficient propyzamide-degrading strain W1 was firstly isolated from activated sludge and identified as Comamonas testosteroni. A metabolite of propyzamide by strain W1 was firstly identified. The novel gene camH encoding a hydrolase that catalyzed the amide bond cleavage of propyzamide was cloned from strain W1. The gene contained an open reading frame of 1452 bp, the deduced amino acid sequence showed low identity with other amidases. The recombinant enzyme CamH was expressed in Escherichia coli BL21 and purified. CamH displayed the highest activity at 30°C and pH 8.0 with propyzamide as the substrate. These results provide important knowledge on the fate of propyzamide in the biodegradation, and elucidate the biodegradation mechanism of propyzamide by the strain W1.
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Affiliation(s)
- Baiping Zhao
- Department of Pesticide Science, College of Plant Protection, Nanjing Agricultural University, State & Local Joint Engineering Research Center of Green Pesticide Invention and Application, Nanjing 210095, China
| | - Xiude Hua
- Department of Pesticide Science, College of Plant Protection, Nanjing Agricultural University, State & Local Joint Engineering Research Center of Green Pesticide Invention and Application, Nanjing 210095, China
| | - Fei Wang
- College of Life Science, Nanjing Agricultural University, Nanjing 210095, China; College of Bioscience and Bioengineering, Jiangxi Agriculture University, Nanchang 330045, China
| | - Weiliang Dong
- College of Life Science, Nanjing Agricultural University, Nanjing 210095, China
| | - Zhoukun Li
- College of Life Science, Nanjing Agricultural University, Nanjing 210095, China
| | - Yu Yang
- Department of Pesticide Science, College of Plant Protection, Nanjing Agricultural University, State & Local Joint Engineering Research Center of Green Pesticide Invention and Application, Nanjing 210095, China
| | - Zhongli Cui
- College of Life Science, Nanjing Agricultural University, Nanjing 210095, China
| | - Minghua Wang
- Department of Pesticide Science, College of Plant Protection, Nanjing Agricultural University, State & Local Joint Engineering Research Center of Green Pesticide Invention and Application, Nanjing 210095, China.
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Abstract
Chlorophenols (CPs) and their derivatives are persistent environmental pollutants which are used in the manufacture of dyes, drugs, pesticides and other industrial products. CPs, which include monochlorophenols, polychlorophenols, chloronitrophenols, chloroaminophenols and chloromethylphenols, are highly toxic to living beings due to their carcinogenic, mutagenic and cytotoxic properties. Several physico-chemical and biological methods have been used for removal of CPs from the environment. Bacterial degradation has been considered a cost-effective and eco-friendly method of removing CPs from the environment. Several bacteria that use CPs as their sole carbon and energy sources have been isolated and characterized. Additionally, the metabolic pathways for degradation of CPs have been studied in bacteria and the genes and enzymes involved in the degradation of various CPs have been identified and characterized. This review describes the biochemical and genetic basis of the degradation of CPs and their derivatives.
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Affiliation(s)
- Pankaj Kumar Arora
- School of Biotechnology, Yeungnam University, Gyeongsan 712-749, Republic of Korea
| | - Hanhong Bae
- School of Biotechnology, Yeungnam University, Gyeongsan 712-749, Republic of Korea
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15
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Hupert-Kocurek K, Wojcieszyńska D, Guzik U. Activity of a carboxyl-terminal truncated form of catechol 2,3-dioxygenase from Planococcus sp. S5. ScientificWorldJournal 2014; 2014:598518. [PMID: 24693238 DOI: 10.1155/2014/598518] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2013] [Accepted: 12/26/2013] [Indexed: 11/17/2022] Open
Abstract
Catechol 2,3-dioxygenases (C23Os, E.C.1.13.12.2) are two domain enzymes that catalyze degradation of monoaromatic hydrocarbons. The catalytically active C-domain of all known C23Os comprises ferrous ion ligands as well as residues forming active site pocket. The aim of this work was to examine and discuss the effect of nonsense mutation at position 289 on the activity of catechol 2,3-dioxygenase from Planococcus strain. Although the mutant C23O showed the same optimal temperature for activity as the wild-type protein (35°C), it exhibited activity slightly more tolerant to alkaline pH. Mutant enzyme exhibited also higher affinity to catechol as a substrate. Its Km (66.17 µM) was approximately 30% lower than that of wild-type enzyme. Interestingly, removal of the C-terminal residues resulted in 1.5- to 1.8-fold (P < 0.05) increase in the activity of C23OB61 against 4-methylcatechol and 4-chlorocatechol, respectively, while towards catechol the activity of the protein dropped to about 80% of that of the wild-type enzyme. The results obtained may facilitate the engineering of the C23O for application in the bioremediation of polluted areas.
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16
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Cui Y, Woo SG, Lee J, Sinha S, Kang MS, Jin L, Kim KK, Park J, Lee M, Lee ST. Nocardioides daeguensis sp. nov., a nitrate-reducing bacterium isolated from activated sludge of an industrial wastewater treatment plant. Int J Syst Evol Microbiol 2013; 63:3727-3732. [PMID: 23645020 DOI: 10.1099/ijs.0.047043-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A Gram-reaction-positive, rod-shaped, non-spore-forming bacterium (strain 2C1-5(T)) was isolated from activated sludge of an industrial wastewater treatment plant in Daegu, South Korea. Its taxonomic position was investigated by using a polyphasic approach. On the basis of 16S rRNA gene sequence similarity, the closest phylogenetic relatives were the type strains of Nocardioides nitrophenolicus (98.6 % similarity), N. kongjuensis (98.5 %), N. caeni (98.4 %), N. simplex (98.3 %), N. aromaticivorans (98.1 %) and N. ginsengisoli (97.5 %); the phylogenetic distance from other species with validly published names within the genus Nocardioides was greater than 3 %. Strain 2C1-5(T) was characterized chemotaxonomically as having ll-2,6-diaminopimelic acid in the cell-wall peptidoglycan, MK-8(H4) as the predominant menaquinone and iso-C16 : 0, C16 : 0 and C17 : 1ω6c as the major fatty acids. The G+C content of the genomic DNA was 74.9 mol%. These chemotaxonomic properties and phenotypic characteristics supported the affiliation of strain 2C1-5(T) to the genus Nocardioides. The results of physiological and biochemical tests allowed genotypic and phenotypic differentiation of strain 2C1-5(T) from existing species with validly published names. Therefore, strain 2C1-5(T) represents a novel species of the genus Nocardioides, for which the name Nocardioides daeguensis sp. nov. is proposed, with the type strain 2C1-5(T) ( = JCM 17460(T) = KCTC 19799(T)).
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Affiliation(s)
- Yingshun Cui
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, 373-1 Guseong-dong, Yuseong-gu, Daejeon 305-701, Republic of Korea
| | - Sung-Geun Woo
- Research and Development Division, H-Plus Eco Ltd, BVC #301, KRIBB, Eoeun-dong, Yuseong-gu, Daejeon 305-333, Republic of Korea.,School of Civil and Environmental Engineering, Yonsei University, Seoul 120-749, Republic of Korea
| | - Jangho Lee
- School of Civil and Environmental Engineering, Yonsei University, Seoul 120-749, Republic of Korea
| | - Sahastranshu Sinha
- Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur 721302, West Bengal, India.,Research and Development Division, H-Plus Eco Ltd, BVC #301, KRIBB, Eoeun-dong, Yuseong-gu, Daejeon 305-333, Republic of Korea
| | - Myung-Suk Kang
- National Institute of Biological Resources, Environmental Research Complex, Gyeongseo-dong, Seo-gu, Incheon 404-708, Republic of Korea
| | - Long Jin
- Environmental Biotechnology Research Center, Korea Research Institute of Bioscience & Biotechnology, 52 Eoeun-dong, Yuseong-gu, Daejeon 305-806, Republic of Korea
| | - Kwang Kyu Kim
- Korean Collection for Type Cultures, Biological Resource Center, Korea Research Institute of Bioscience and Biotechnology, 52 Eoeun-dong, Yuseong-gu, Daejeon 305-806, Republic of Korea
| | - Joonhong Park
- School of Civil and Environmental Engineering, Yonsei University, Seoul 120-749, Republic of Korea
| | - Myungjin Lee
- WIZCHEM Co., Ltd. Inno-Biz Park No. 403 HNU, 461-6 Jeonmin-dong, Yuseong-gu, Daejeon, 305-811, Republic of Korea
| | - Sung-Taik Lee
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, 373-1 Guseong-dong, Yuseong-gu, Daejeon 305-701, Republic of Korea
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Cui Y, Kang MS, Woo SG, Jin L, Kim KK, Park J, Lee M, Lee ST. Brevibacterium daeguense sp. nov., a nitrate-reducing bacterium isolated from a 4-chlorophenol enrichment culture. Int J Syst Evol Microbiol 2013; 63:152-157. [DOI: 10.1099/ijs.0.038141-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A Gram-reaction-positive, non-spore-forming, aerobic actinobacterial strain (2C6-41T) was isolated from the activated sludge from an industrial wastewater treatment plant in Daegu, South Korea. Its taxonomic position was investigated by using a polyphasic approach. On the basis of 16S rRNA gene sequence similarity, closest phylogenetic relatives to strain 2C6-41T were
Brevibacterium pityocampae
DSM 21720T (97.2 %),
Brevibacterium salitolerans
KCTC 19616T (96.7 %),
Brevibacterium album
KCTC 19173T (96.2 %) and
Brevibacterium samyangense
KCCM 42316T (96.2 %). The DNA G+C content of strain 2C6-41T was 66.4 mol%. Chemotaxonomic data, which included MK-8(H2) as the major menaquinone; meso-diaminopimelic acid, glutamic acid and alanine as cell-wall amino acids; ribose, mannose and glucose as major cell-wall sugars; and anteiso-C15 : 0, anteiso-C17 : 0, C16 : 0 and iso-C15 : 0 as major fatty acids, supported the affiliation of strain 2C6-41T to the genus
Brevibacterium
. The aromatic ring cleavage enzyme catechol 1,2-dioxygenase was not detected in strain 2C6-41T, but catechol 2,3-dioxygenase was detected. The results of physiological and biochemical tests, and the low level of DNA–DNA relatedness to the closest phylogenetic relative enabled strain 2C6-41T to be differentiated genotypically and phenotypically from recognized species of the genus
Brevibacterium
. The isolate is therefore considered to represent a novel species in the genus
Brevibacterium
, for which the name Brevibacterium daeguense sp. nov. is proposed. The type strain is 2C6-41T ( = KCTC 19800T = JCM 17458T).
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Affiliation(s)
- Yingshun Cui
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, 373-1, Guseong-dong, Yuseong-gu, Daejeon 305-701, Republic of Korea
| | - Myung-Suk Kang
- National Institute of Biological Resources, Environmental Research Complex, Gyeongseo-dong, Seo-gu, Incheon 404-708, Republic of Korea
| | - Sung-Geun Woo
- Research and Development Division, H-Plus Eco Ltd, BVC #301, KRIBB, Eoeun-dong, Yuseong-gu, Daejeon 305-333, Republic of Korea
- School of Civil and Environmental Engineering, Yonsei University, Seoul 120-749, Republic of Korea
| | - Long Jin
- Environmental Biotechnology Research Center, Korea Research Institute of Bioscience & Biotechnology, 52 Eoeun-dong, Yuseong-gu, Daejeon 305-806, Republic of Korea
| | - Kwang Kyu Kim
- Korean Collection for Type Cultures, Biological Resource Center, Korea Research Institute of Bioscience and Biotechnology, 52 Eoeun-dong, Yuseong-gu, Daejeon 305-806, Republic of Korea
| | - Joonhong Park
- School of Civil and Environmental Engineering, Yonsei University, Seoul 120-749, Republic of Korea
| | - Myungjin Lee
- Research and Development Division, H-Plus Eco Ltd, BVC #301, KRIBB, Eoeun-dong, Yuseong-gu, Daejeon 305-333, Republic of Korea
| | - Sung-Taik Lee
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, 373-1, Guseong-dong, Yuseong-gu, Daejeon 305-701, Republic of Korea
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Woo SG, Cui Y, Kang MS, Jin L, Kim KK, Lee ST, Lee M, Park J. Georgenia daeguensis sp. nov., isolated from 4-chlorophenol enrichment culture. Int J Syst Evol Microbiol 2012; 62:1703-1709. [DOI: 10.1099/ijs.0.033217-0] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
During screening for 4-chlorophenol-degrading micro-organisms in activated sludge from industrial wastewater treatment, a Gram-positive, rod-shaped, aerobic bacterial strain, designated 2C6-43T, was isolated and characterized taxonomically by using a polyphasic approach. Comparative 16S rRNA gene sequence analysis showed that strain 2C6-43T belongs to the family
Bogoriellaceae
, class
Actinobacteria
, and is related most closely to
Georgenia soli
CC-NMPT-T3T (98.8 % sequence similarity),
Georgenia muralis
1A-CT (97.6 %),
Georgenia thermotolerans
TT02-04T (96.8 %),
Georgenia ruanii
YIM 004T (96.6 %) and
Georgenia halophila
YIM 93316T (96.0 %). The G+C content of the genomic DNA of strain 2C6-43T was 66.2 mol%. Sugars from whole-cell hydrolysates found in strain 2C6-43T were rhamnose, ribose and galactose. The menaquinone MK-8(H4) was detected as the predominant quinone. Polar lipid analysis of 2C6-43T revealed diphosphatidylglycerol, phosphatidylinositol mannoside, phosphatidylinositol and phosphatidylglycerol. An aromatic compound ring cleavage enzyme of catechol 1,2-dioxygenase was detected but catechol 2,3-dioxygenase was not detected in 2C6-43T. A fatty acid profile with anteiso-C15 : 0, iso-C15 : 0 and C16 : 0 as the major components supported the affiliation of strain 2C6-43T to the genus
Georgenia
. However, the DNA–DNA relatedness between strain 2C6-43T and the type strains of five species of the genus
Georgenia
ranged from 17 to 40 %, clearly showing that the isolate constitutes a new genospecies. Strain 2C6-43T could be clearly differentiated from its phylogenetic neighbours on the basis of some phenotypic, genotypic and chemotaxonomic features. Therefore, strain 2C6-43T is considered to represent a novel species of the genus
Georgenia
, for which the name Georgenia daeguensis sp. nov. is proposed; the type strain is 2C6-43T ( = KCTC 19801T = JCM 17459T).
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Affiliation(s)
- Sung-Geun Woo
- Research and Development Division, H-Plus Eco Ltd, BVC 301, KRIBB, Eoeun-dong, Yuseong-gu, Daejeon 305-333, Republic of Korea
- WCU Center for Green Metagenomics, Yonsei University, Seoul 120-749, Republic of Korea
- School of Civil and Environmental Engineering, Yonsei University, Seoul 120-749, Republic of Korea
| | - Yingshun Cui
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, 373-1 Guseong-dong, Yuseong-gu, Daejeon 305-701, Republic of Korea
| | - Myung-Suk Kang
- National Institute of Biological Resources, Environmental Research Complex, Gyeongseo-dong, Seo-gu, Incheon 404-708, Republic of Korea
| | - Long Jin
- Environmental Biotechnology Research Center, Korea Research Institute of Bioscience & Biotechnology, 52 Eoeun-dong, Yuseong-gu, Daejeon 305-806, Republic of Korea
| | - Kwang Kyu Kim
- Korean Collection for Type Cultures, Biological Resource Center, Korea Research Institute of Bioscience and Biotechnology, 52 Eoeun-dong, Yuseong-gu, Daejeon 305-806, Republic of Korea
| | - Sung-Taik Lee
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, 373-1 Guseong-dong, Yuseong-gu, Daejeon 305-701, Republic of Korea
| | - Myungjin Lee
- Research and Development Division, H-Plus Eco Ltd, BVC 301, KRIBB, Eoeun-dong, Yuseong-gu, Daejeon 305-333, Republic of Korea
| | - Joonhong Park
- WCU Center for Green Metagenomics, Yonsei University, Seoul 120-749, Republic of Korea
- School of Civil and Environmental Engineering, Yonsei University, Seoul 120-749, Republic of Korea
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Silva CC, Hayden H, Sawbridge T, Mele P, Kruger RH, Rodrigues MVN, Costa GGL, Vidal RO, Sousa MP, Torres APR, Santiago VMJ, Oliveira VM. Phylogenetic and functional diversity of metagenomic libraries of phenol degrading sludge from petroleum refinery wastewater treatment system. AMB Express 2012; 2:18. [PMID: 22452812 PMCID: PMC3366876 DOI: 10.1186/2191-0855-2-18] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2012] [Accepted: 03/27/2012] [Indexed: 01/24/2023] Open
Abstract
In petrochemical refinery wastewater treatment plants (WWTP), different concentrations of pollutant compounds are received daily in the influent stream, including significant amounts of phenolic compounds, creating propitious conditions for the development of particular microorganisms that can rapidly adapt to such environment. In the present work, the microbial sludge from a refinery WWTP was enriched for phenol, cloned into fosmid vectors and pyrosequenced. The fosmid libraries yielded 13,200 clones and a comprehensive bioinformatic analysis of the sequence data set revealed a complex and diverse bacterial community in the phenol degrading sludge. The phylogenetic analyses using MEGAN in combination with RDP classifier showed a massive predominance of Proteobacteria, represented mostly by the genera Diaphorobacter, Pseudomonas, Thauera and Comamonas. The functional classification of phenol degrading sludge sequence data set generated by MG-RAST showed the wide metabolic diversity of the microbial sludge, with a high percentage of genes involved in the aerobic and anaerobic degradation of phenol and derivatives. In addition, genes related to the metabolism of many other organic and xenobiotic compounds, such as toluene, biphenyl, naphthalene and benzoate, were found. Results gathered herein demonstrated that the phenol degrading sludge has complex phylogenetic and functional diversities, showing the potential of such community to degrade several pollutant compounds. This microbiota is likely to represent a rich resource of versatile and unknown enzymes which may be exploited for biotechnological processes such as bioremediation.
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Tobajas M, Monsalvo VM, Mohedano AF, Rodriguez JJ. Enhancement of cometabolic biodegradation of 4-chlorophenol induced with phenol and glucose as carbon sources by Comamonas testosteroni. J Environ Manage 2012; 95 Suppl:S116-S121. [PMID: 20970917 DOI: 10.1016/j.jenvman.2010.09.030] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2009] [Revised: 07/22/2010] [Accepted: 09/03/2010] [Indexed: 05/30/2023]
Abstract
The biological degradation of phenol and 4-chlorophenol (4-CP) by Comamonas testosteroni CECT 326T has been studied. Phenol and 4-CP were treated alone as a sole carbon and energy source, but only phenol was completely degraded by C. testosteroni. Since the presence of cosubstrates can enhance the toxic compounds removal by pure cultures, phenol and glucose were added as growth substrates for cometabolic transformation of 4-CP. High efficiencies were obtained in all the experiments carried out in presence of both cosubstrates. In spite of the fact that the addition of glucose reduced the lag phase of 4-CP removal, lower phenol concentrations were required to obtain the same degradation efficiencies. The cometabolic transformation of 4-CP was closely related with the extent of phenol removal. The values of the 4-CP/biomass concentration ratio (S/X) obtained for discriminating between complete (S/X ≤ 0.11) and partial 4-CP (S/X ≥ 0.31) transformation showed a narrower range than that reported in the literature. The extent of the cometabolic 4-CP transformation in the presence of phenol could be further enhanced by using glucose as an additional carbon and energy source. However, no significant influence of glucose concentration on 4-CP removal was observed over the concentration range studied.
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Affiliation(s)
- Montserrat Tobajas
- Sección de Ingeniería Química, Facultad de Ciencias, Universidad Autónoma de Madrid, C/Francisco Tomás y Valiente 7, 28049 Madrid, Spain.
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Olaniran AO, Igbinosa EO. Chlorophenols and other related derivatives of environmental concern: properties, distribution and microbial degradation processes. Chemosphere 2011; 83:1297-306. [PMID: 21531434 DOI: 10.1016/j.chemosphere.2011.04.009] [Citation(s) in RCA: 241] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2011] [Revised: 04/01/2011] [Accepted: 04/04/2011] [Indexed: 05/24/2023]
Abstract
Chlorophenols are chlorinated aromatic compound structures and are commonly found in pesticide preparations as well as industrial wastes. They are recalcitrant to biodegradation and consequently persistent in the environment. A variety of chlorophenols derivatives compounds are highly toxic, mutagenic and carcinogenic for living organisms. Biological transformation by microorganisms is one of the key remediation options that can be exploited to solve environmental pollution problems caused by these notorious compounds. The key enzymes in the microbial degradation of chlorophenols are the oxygenases and dioxygenases. These enzymes can be engineered for enhanced degradation of highly chlorinated aromatic compounds through directed evolution methods. This review underscores the mechanisms of chlorophenols biodegradation with the view to understanding how bioremediation processes can be optimized for cleaning up chloroaromatic contaminated environments.
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Affiliation(s)
- Ademola O Olaniran
- Discipline of Microbiology, School of Biochemistry, Genetics and Microbiology, Faculty of Science and Agriculture, University of KwaZulu-Natal (Westville Campus), Private Bag X54001, Durban 4000, South Africa.
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Liu Z, Yang C, Jiang H, Mulchandani A, Chen W, Qiao C. Simultaneous degradation of organophosphates and 4-substituted phenols by Stenotrophomonas species LZ-1 with surface-displayed organophosphorus hydrolase. J Agric Food Chem 2009; 57:6171-6177. [PMID: 19548671 DOI: 10.1021/jf804008j] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Organophosphorous hydrolase (OPH) was expressed onto the surface of a Stenotrophomonas species (LZ-1), capable of simultaneously degrading 4-substituted phenols, using the N- and C-terminal domains of ice nucleation protein (INPNC) as an anchoring motif for the first time. The engineered strain LZ-1 could degrade p-nitrophenyl-substituted organophosphates as well as their hydrolytic product, PNP, rapidly. Especially, addition of 4-CP (below 0.8 mM) significantly accelerated the complete degradation of above organophosphates (47.1, 34.0, and 40% reduction of time of paraoxon, parathion, and methyl-parathion, respectively) through the accelerated degradation of PNP due to enhanced cell growth supported by 4-CP as the carbon source. OPH could be surface-displayed at a high level without inhibition of cell growth and OPH activity in the presence of 4-CP. In soil samples, strain LZ-1 could also remove these compounds successfully. Functional display of heterologous proteins on the surface of indigenous bacteria could provide a promising technology for effective bioremediation of sites contaminated with mixed organic pollutants.
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Affiliation(s)
- Zheng Liu
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100080, China
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Zuzana S, Katarína D, Lívia T. Biodegradation and ecotoxicity of soil contaminated by pentachlorophenol applying bioaugmentation and addition of sorbents. World J Microbiol Biotechnol 2009; 25:243-52. [DOI: 10.1007/s11274-008-9885-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Abstract
A bacterium named LZ-1 capable of utilizing high concentrations of p-nitrophenol (PNP) (up to 500 mg L(-1)) as the sole source of carbon, nitrogen and energy was isolated from an activated sludge. Based on the results of phenotypic features and phylogenetic similarity of 16S rRNA gene sequences, strain LZ-1 was identified as a Stenotrophomonas sp. Other p-substituted phenols such as 4-chlorophenol (4-CP) were also degraded by strain LZ-1, and both PNP and 4-CP were degraded via the hydroquinone pathway exclusively. Strain LZ-1 could degrade PNP and 4-CP simultaneously and the degradation of PNP was greatly accelerated due to the increased biomass supported by 4-CP. An indigenous plasmid was found to be responsible for phenols degradation. In soil samples, 100 mg kg(-1) of PNP and 4-CP in mixtures were removed by strain LZ-1 (10(6) cells g(-1)) within 14 and 16 days respectively, and degradation activity was maintained over a wide range of temperatures (4-35 degrees C). Therefore, strain LZ-1 can potentially be used in bioremediation of phenolic compounds either individually or as a mixture in the environment.
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Rothballer M, Schmid M, Klein I, Gattinger A, Grundmann S, Hartmann A. Herbaspirillum hiltneri sp. nov., isolated from surface-sterilized wheat roots. Int J Syst Evol Microbiol 2006; 56:1341-1348. [PMID: 16738112 DOI: 10.1099/ijs.0.64031-0] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The genus Herbaspirillum of the Betaproteobacteria mainly comprises diazotrophic bacteria with a potential for endophytic and systemic colonization of a variety of plants. The plant-associated bacterial isolates N3T, N5 and N9 were derived from surface-sterilized wheat roots. After phylogenetic analysis of 16S rRNA gene sequence data the isolates could be allocated to the genus Herbaspirillum, and 99.9 % similarity to the sequence of Herbaspirillum lusitanum P6-12T was found. A set of 16S rRNA gene-targeted oligonucleotide probes was developed for the identification of the three novel isolates and H. lusitanum (Hhilu446), and for the specific detection of several other Herbaspirillum species described recently. For higher phylogenetic resolution, the 23S rRNA gene sequences of all members of the genus was sequenced and used to construct a phylogenetic tree. Isolates N3T, N5 and N9 formed a group that was distinct from all other Herbaspirillum species. In addition, isolate N3T and H. lusitanum P6-12T exhibited a DNA–DNA hybridization value of only 25 %. The value for DNA–DNA hybridization between N3T and other members of the genus Herbaspirillum was between 14 and 32 %; DNA–DNA hybridization between strain N3T and isolates N5 and N9 produced values above 95 %. This places the three isolates as representatives of a novel species within the genus Herbaspirillum. A Biolog GN2 assay supported this conclusion. The major fatty acids were C16 : 1
ω7c, C16 : 0 and C18 : 1
ω7c, and the DNA G+C content ranged from 60.9 to 61.5 mol%. Therefore these three isolates should be classified within a novel species, for which the name Herbaspirillum hiltneri sp. nov. is proposed. The type strain is N3T (=DSM 17495T=LMG 23131T).
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Affiliation(s)
- Michael Rothballer
- Department of Rhizosphere Biology, GSF - National Research Centre for Environment and Health, Ingolstaedter Landstrasse 1, D-85764 Neuherberg, Germany
| | - Michael Schmid
- Department of Rhizosphere Biology, GSF - National Research Centre for Environment and Health, Ingolstaedter Landstrasse 1, D-85764 Neuherberg, Germany
| | - Ilona Klein
- Department of Rhizosphere Biology, GSF - National Research Centre for Environment and Health, Ingolstaedter Landstrasse 1, D-85764 Neuherberg, Germany
| | - Andreas Gattinger
- Institute of Soil Ecology, GSF - National Research Centre for Environment and Health, Ingolstaedter Landstrasse 1, D-85764 Neuherberg, Germany
| | - Sabine Grundmann
- Institute of Soil Ecology, GSF - National Research Centre for Environment and Health, Ingolstaedter Landstrasse 1, D-85764 Neuherberg, Germany
| | - Anton Hartmann
- Department of Rhizosphere Biology, GSF - National Research Centre for Environment and Health, Ingolstaedter Landstrasse 1, D-85764 Neuherberg, Germany
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Abstract
Bacterial isolates Comamonas terrigena N3H (from soil contaminated with crude oil) and C. testosteroni (isolated from the sludge of a wastewater treatment plant), exhibit much higher total catalase activity than the same species from laboratory collection cultures. Electrophoretic resolution of catalases revealed only one corresponding band in cell-free extracts of both C. testosteroni cultures. Isolates of C. terrigena N3H exhibited catalase-1 and catalase-2 activity, whereas in the collection culture C. terrigena ATCC 8461 only catalase-1 was detected. The environmental isolates exhibited much higher resistance to exogenous H2O2 (20, 40 mmol/L) than collection cultures, mainly in the middle and late exponential growth phases. The stepwise H2O2-adapted culture of C. terrigena N3H, which was more resistant to oxidative stress than the original isolate, exhibited an increase of catalase and peroxidase activity represented by catalase-1. Pretreatment of cells with 0.5 mmol/L H2O2 followed by an application of the oxidative agent in toxic concentrations (up to 40 mmol/L) increased the rate of cell survival in the original isolate, but not in the H2O2-adapted variant. The protection of bacteria caused by such pretreatment corresponded with stimulation of catalase activity in pretreated culture.
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Affiliation(s)
- J Godocíková
- Institute of Molecular Biology, Centre of Excellence, Slovak Academy of Sciences, 845 51 Bratislava, Slovakia.
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Tarasevich M, Chirkov Y, Bogdanovskaya V, Kapustin A. Fractal and percolation properties of active layer structure at oxygen electrode based on nanocomposite material of dispersed carbon carrier/laccase. Electrochim Acta 2005; 51:418-26. [DOI: 10.1016/j.electacta.2005.04.037] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Abstract
A taxonomic study was carried out on Chj404T, a bacterial strain isolated from a soil sample collected in an industrial stream near the Chung-Ju industrial complex in Korea. The strain was a gram-negative, aerobic, short rod to coccus-shaped bacterium. It grew well on nutrient agar medium and utilized a broad spectrum of carbon sources. The G+C content of the DNA was 67.4 mol% and the major composition of ubiquinone was Q-10. The major fatty acid was C18:1. Comparative 16S rDNA studies showed a clear affiliation of this bacterium to alpha-Proteobacteria. Comparison of phylogenetic data indicated that it was most closely related to Prosthecomicrobium pneumaticum (92.7% similarity in 16S rDNA sequence). Since strain Chj404 is clearly distinct from closely related species, we propose the name Kaistia adipata gen. nov., sp. nov. for this strain Chj404T (=IAM 15023T=KCTC 12095T).
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Affiliation(s)
- Wan-Taek Im
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, 373-1, Guseong-dong, Yuseong-gu, Daejeon 305-701, Republic of Korea
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29
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Abstract
A 4-chlorophenol-degrading bacterial strain, formerly designated as a strain of Comamonas testosteroni, was reclassified as a member of the genus Herbaspirillum based on its phenotypic and chemotaxonomic characteristics, as well as phylogenetic analysis using 16S rDNA sequences. Phylogenetic inference based on 16S rDNA sequences showed that strain CPW301T clusters in a phylogenetic branch that contains Herbaspirillum species. 16S rDNA sequence similarity of strain CPW301T to species of the genus Herbaspirillum with validly published names is in the range 98·7–98·9 %. Despite the considerably high 16S rDNA sequence similarity, strain CPW301T could be distinguished clearly from type strains of Herbaspirillum species with validly published names by DNA–DNA relatedness values, which were <15·7 %. The genomic DNA G+C content of strain CPW301T is 61·3 mol%. The predominant ubiquinone is Q-8 and the major cellular fatty acids are C16 : 0 and cyclo-C17 : 0. The strain does not fix nitrogen and is not plant-associated. It is an aerobic rod with one unipolar flagellum. On the basis of these characteristics, a novel Herbaspirillum species, Herbaspirillum chlorophenolicum sp. nov., is proposed. The type strain of the novel species is strain CPW301T (=KCTC 12096T=IAM 15024T).
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Affiliation(s)
- Wan-Taek Im
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, 373-1, Guseong-dong, Yuseong-gu, Daejeon 305-701, Korea
| | - Hee-Sung Bae
- Department of Biological Sciences, 331 Life Sciences Building, LSU, Baton Rouge, LA 70803, USA
| | - Akira Yokota
- Institute of Molecular and Cellular Biosciences, University of Tokyo, 1-1, Yayoi 1-chome, Bunkyo-ku, Tokyo, 113-0032, Japan
| | - Sung Taik Lee
- Department of Biological Sciences, Korea Advanced Institute of Science and Technology, 373-1, Guseong-dong, Yuseong-gu, Daejeon 305-701, Korea
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Tarasevich M, Bogdanovskaya V, Kapustin A. Nanocomposite material laccase/dispersed carbon carrier for oxygen electrode. Electrochem commun 2003; 5:491-6. [DOI: 10.1016/s1388-2481(03)00104-8] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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31
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Kim J, Oh K, Lee S, Kim S, Hong S. Biodegradation of phenol and chlorophenols with defined mixed culture in shake-flasks and a packed bed reactor. Process Biochem 2002; 37:1367-73. [DOI: 10.1016/s0032-9592(02)00007-9] [Citation(s) in RCA: 93] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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32
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Boon N, Goris J, De Vos P, Verstraete W, Top EM. Bioaugmentation of activated sludge by an indigenous 3-chloroaniline-degrading Comamonas testosteroni strain, I2gfp. Appl Environ Microbiol 2000; 66:2906-13. [PMID: 10877785 PMCID: PMC92090 DOI: 10.1128/aem.66.7.2906-2913.2000] [Citation(s) in RCA: 282] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/1999] [Accepted: 04/17/2000] [Indexed: 11/20/2022] Open
Abstract
A strain identified as Comamonas testosteroni I2 was isolated from activated sludge and found to be able to mineralize 3-chloroaniline (3-CA). During the mineralization, a yellow intermediate accumulated temporarily, due to the distal meta-cleavage of chlorocatechol. This strain was tested for its ability to clean wastewater containing 3-CA upon inoculation into activated sludge. To monitor its survival, the strain was chromosomally marked with the gfp gene and designated I2gfp. After inoculation into a lab-scale semicontinuous activated-sludge (SCAS) system, the inoculated strain maintained itself in the sludge for at least 45 days and was present in the sludge flocs. After an initial adaptation period of 6 days, complete degradation of 3-CA was obtained during 2 weeks, while no degradation at all occurred in the noninoculated control reactor. Upon further operation of the SCAS system, only 50% 3-CA removal was observed. Denaturing gradient gel electrophoresis (DGGE) of 16S rRNA genes revealed a dynamic change in the microbial community structure of the activated sludge. The DGGE patterns of the noninoculated and the inoculated reactors evolved after 7 days to different clusters, which suggests an effect of strain inoculation on the microbial community structure. The results indicate that bioaugmentation, even with a strain originating from that ecosystem and able to effectively grow on a selective substrate, is not permanent and will probably require regular resupplementation.
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Affiliation(s)
- N Boon
- Laboratory of Microbial Ecology and Technology, Ghent University, B-9000 Ghent, Belgium
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