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Zhang W, Jiang Y, Wen Q, Zhao Y, Wu B, Huang W. Inhibit or promote? Trade-off effect of dissolved organic matter on the laccase-mediator system. JOURNAL OF HAZARDOUS MATERIALS 2024; 473:134595. [PMID: 38761769 DOI: 10.1016/j.jhazmat.2024.134595] [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: 01/03/2024] [Revised: 05/04/2024] [Accepted: 05/10/2024] [Indexed: 05/20/2024]
Abstract
A biocatalytic system comprising fungal laccase and mediators can generate phenol radicals and efficiently eliminate various triarylmethane dyes. This study systematically explores the kinetic impact of dissolved organic matter (DOM), represented by humic substance (HS consisting of 90% fulvic acid, from lignite), on the decolorization of seven typical triarylmethane dyes by Trametes versicolor laccase and twenty natural mediators. Among these, 4-hydroxybenzyl alcohol (4-HA) and methyl violet (MV) undergo in-depth investigation regarding degradation products, pathways, and reaction mechanisms. In instances where HS hampers laccase-alone decolorization, such as malachite green, Coomassie brilliant blue, bromophenol blue, and acid magenta, this inhibition may persist despite mediator introduction. Conversely, in cases where HS facilitates decolorization, such as crystalline violet and ethyl violet, most laccase-mediator systems (LMSs) can still benefit. For MV decolorization by laccase and 4-HA, HS's kinetic effect is controlled by concentration and reaction time. A 5 mg/L HS increased the decolorization rate from 50% to 67% within the first hour, whereas 10 mg/L HS only achieved 45%. After 16 h of reaction, HS's impact on decolorization rate diminishes. Furthermore, the addition of HS enhances precipitation production, probably due to its involvement in polymerization with MV and mediator. Computational simulations and spectral monitoring reveal that low HS concentrations accelerate laccase-mediated demethylation by disrupting the chromophores bound to MV, thus promoting the decolorization of MV. Conversely, inhibition by high HS concentrations stems from the competitive binding of the enzyme pocket to the mediator, and the reduction of phenol free radicals in the system. Molecular docking and kinetic simulations revealed that laccase forms complexes with both the mediator and MV. Interestingly, the decolorization of MV occurred through a non-radical mechanism in the presence of HS. This work provided a reference for screening of high catalytic performance mediators to remove triarylmethane dyes in the actual water environment.
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Affiliation(s)
- Wentao Zhang
- Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, People's Republic of China
| | - Yunlin Jiang
- South China Institute of Environmental Sciences, Ministry of Ecology and Environment of PRC, Guangzhou 510655, People's Republic of China
| | - Qingqi Wen
- College of Resources and Environment, Zhongkai University of Agriculture and Engineering, Guangzhou 510225, People's Republic of China
| | - Yue Zhao
- School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou 215002, People's Republic of China
| | - Bingdang Wu
- School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou 215002, People's Republic of China; Key Laboratory of Suzhou Sponge City Technology, Suzhou 215009, People's Republic of China.
| | - Wenguang Huang
- South China Institute of Environmental Sciences, Ministry of Ecology and Environment of PRC, Guangzhou 510655, People's Republic of China.
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2
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Scheibel DM, Gitsov IPI, Gitsov I. Enzymes in "Green" Synthetic Chemistry: Laccase and Lipase. Molecules 2024; 29:989. [PMID: 38474502 DOI: 10.3390/molecules29050989] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2023] [Revised: 02/14/2024] [Accepted: 02/22/2024] [Indexed: 03/14/2024] Open
Abstract
Enzymes play an important role in numerous natural processes and are increasingly being utilized as environmentally friendly substitutes and alternatives to many common catalysts. Their essential advantages are high catalytic efficiency, substrate specificity, minimal formation of byproducts, and low energy demand. All of these benefits make enzymes highly desirable targets of academic research and industrial development. This review has the modest aim of briefly overviewing the classification, mechanism of action, basic kinetics and reaction condition effects that are common across all six enzyme classes. Special attention is devoted to immobilization strategies as the main tools to improve the resistance to environmental stress factors (temperature, pH and solvents) and prolong the catalytic lifecycle of these biocatalysts. The advantages and drawbacks of methods such as macromolecular crosslinking, solid scaffold carriers, entrapment, and surface modification (covalent and physical) are discussed and illustrated using numerous examples. Among the hundreds and possibly thousands of known and recently discovered enzymes, hydrolases and oxidoreductases are distinguished by their relative availability, stability, and wide use in synthetic applications, which include pharmaceutics, food and beverage treatments, environmental clean-up, and polymerizations. Two representatives of those groups-laccase (an oxidoreductase) and lipase (a hydrolase)-are discussed at length, including their structure, catalytic mechanism, and diverse usage. Objective representation of the current status and emerging trends are provided in the main conclusions.
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Affiliation(s)
- Dieter M Scheibel
- Department of Chemistry, State University of New York-ESF, Syracuse, NY 13210, USA
| | - Ioan Pavel Ivanov Gitsov
- Science and Technology, Medtronic Incorporated, 710 Medtronic Parkway, Minneapolis, MN 55432, USA
| | - Ivan Gitsov
- Department of Chemistry, State University of New York-ESF, Syracuse, NY 13210, USA
- The Michael M. Szwarc Polymer Research Institute, Syracuse, NY 13210, USA
- Biomedical and Chemical Engineering Department, Syracuse University, Syracuse, NY 13210, USA
- BioInspired Institute, Syracuse, NY 13210, USA
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3
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Afreen S, Mishra S. Production of high-value oxidative enzymes by Cyathus bulleri on agricultural and agri-food wastes for application in the textile sector. World J Microbiol Biotechnol 2023; 39:329. [PMID: 37792159 DOI: 10.1007/s11274-023-03769-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Accepted: 09/15/2023] [Indexed: 10/05/2023]
Abstract
Ligninolytic and other oxidative enzymes have emerged as promising biocatalysts in several industries. Since their production at a low cost is necessary for any large-scale application, we demonstrate the use of rice bran (RB), an agricultural waste and agri-food wastes such as potato peelings (PP), banana peelings (BP), and green pea peelings (GPP) for their production. High activity of laccase (12 U/ml), manganese peroxidase (16.11 ± 1.43 U/ml), and aryl alcohol oxidase (1.25 U/ml) was obtained on the PP on the 12th day of growth and ~ 6 U/ml of lytic polysaccharide monooxygenase was obtained on the 14th day of growth demonstrating PP to be a good substrate for their production. RB served as the next best substrate for the production of these enzymes. While the GPP was effective for the production of laccase (9.2 U/ml), this and the BP were not good substrates for the production of other enzymes. Efficient (48-82%) decolorization of several azo-, triarylmethane- dyes, and real textile effluent, without the addition of any mediator, demonstrated the high oxidative ability of the crude culture filtrate produced on the PP (CF-PP), which was a significant improvement compared to the treatment given by the previously reported culture filtrate obtained on wheat bran (CF-WB). An extensive breakdown of Reactive Orange (RO) 16 was demonstrated using CF-PP resulting in the formation of a new product at m/z of 294.05 (6-acetamido-3,4-dioxo-3,4-dihydronapthalene-2-sulfonate), previously reported to be produced on ozonation/advanced oxidation of RO16. The predominant laccase and manganese peroxidase isoforms produced on the PP were also identified.
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Affiliation(s)
- Sumbul Afreen
- Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology Delhi, New Delhi, Delhi, 110016, India
| | - Saroj Mishra
- Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology Delhi, New Delhi, Delhi, 110016, India.
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4
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Dahiya M, Islam DT, Srivastava P, Sreekrishnan TR, Mishra S. Detoxification and decolorization of complex textile effluent in an enzyme membrane reactor: batch and continuous studies. Front Microbiol 2023; 14:1193875. [PMID: 37485538 PMCID: PMC10361525 DOI: 10.3389/fmicb.2023.1193875] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2023] [Accepted: 06/19/2023] [Indexed: 07/25/2023] Open
Abstract
There is an urgent need to look for bio-based technologies to address the pollution related to textile dyes in waterbodies. The aim of this study was to evaluate an engineered laccase variant, LCC1-62 of Cyathus bulleri, expressed in recombinant Pichia pastoris, for the decolorization and detoxification of real textile effluent. The partially purified laccase effectively (~60-100%) decolorized combined effluent from different dyeing units at a laccase concentration of 500 U/L at a 50-mL level. Decolorization and detoxification of the combined effluents, from a local textile mill, were evaluated at 0.3 L volumetric level in a ray-flow membrane reactor in batch and continuous modes of operation. In batch studies, maximum decolorization of 97% and detoxification of 96% occurred at a hydraulic retention time (HRT) of 6 h without any additional laccase requirement. In continuous studies, the reactor was operated at an HRT of 6 h with a lower enzyme dosage (~120 U/L of the effluent). Decolorization was accompanied by a loss in laccase activity which was restored to ~120 U/L by the addition of laccase in two regimes. The addition of laccase, when the residual laccase activity decreased to 40% (~50 U/L), resulted in high decolorization (~5 ppm residual dye concentration) and low variance (σ2) of 2.77, while laccase addition, when the residual dye concentration decreased to ~8% (~10 U/L), resulted in an average dye concentration of 13 ppm with a high variance of 62.08. The first regime was implemented, and the continuous reactor was operated for over 80 h at an HRT of 3 and 6 h, with the latter resulting in ~95% decolorization and 96% reduction in the mutagenicity of the effluent. Less than 10% membrane fouling was observed over long operations of the reactor. The findings strongly suggest the feasibility of using LCC1-62 in an enzyme membrane reactor for large-scale treatment of textile effluents.
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Schmidt M, Prager A, Schönherr N, Gläser R, Schulze A. Reagent-Free Immobilization of Industrial Lipases to Develop Lipolytic Membranes with Self-Cleaning Surfaces. MEMBRANES 2022; 12:599. [PMID: 35736306 PMCID: PMC9229154 DOI: 10.3390/membranes12060599] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Revised: 05/30/2022] [Accepted: 06/02/2022] [Indexed: 02/04/2023]
Abstract
Biocatalytic membrane reactors combine the highly efficient biotransformation capability of enzymes with the selective filtration performance of membrane filters. Common strategies to immobilize enzymes on polymeric membranes are based on chemical coupling reactions. Still, they are associated with drawbacks such as long reaction times, high costs, and the use of potentially toxic or hazardous reagents. In this study, a reagent-free immobilization method based on electron beam irradiation was investigated, which allows much faster, cleaner, and cheaper fabrication of enzyme membrane reactors. Two industrial lipase enzymes were coupled onto a polyvinylidene fluoride (PVDF) flat sheet membrane to create self-cleaning surfaces. The response surface methodology (RSM) in the design-of-experiments approach was applied to investigate the effects of three numerical factors on enzyme activity, yielding a maximum activity of 823 ± 118 U m-2 (enzyme concentration: 8.4 g L-1, impregnation time: 5 min, irradiation dose: 80 kGy). The lipolytic membranes were used in fouling tests with olive oil (1 g L-1 in 2 mM sodium dodecyl sulfate), resulting in 100% regeneration of filtration performance after 3 h of self-cleaning in an aqueous buffer (pH 8, 37 °C). Reusability with three consecutive cycles demonstrates regeneration of 95%. Comprehensive membrane characterization was performed by determining enzyme kinetic parameters, permeance monitoring, X-ray photoelectron spectroscopy, FTIR spectroscopy, scanning electron microscopy, and zeta potential, as well as water contact angle measurements.
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Affiliation(s)
- Martin Schmidt
- Leibniz Institute of Surface Engineering (IOM), Permoserstr. 15, 04318 Leipzig, Germany; (M.S.); (A.P.); (N.S.)
| | - Andrea Prager
- Leibniz Institute of Surface Engineering (IOM), Permoserstr. 15, 04318 Leipzig, Germany; (M.S.); (A.P.); (N.S.)
| | - Nadja Schönherr
- Leibniz Institute of Surface Engineering (IOM), Permoserstr. 15, 04318 Leipzig, Germany; (M.S.); (A.P.); (N.S.)
| | - Roger Gläser
- Institute of Chemical Technology, Leipzig University, Linnéstraße 3, 04103 Leipzig, Germany;
| | - Agnes Schulze
- Leibniz Institute of Surface Engineering (IOM), Permoserstr. 15, 04318 Leipzig, Germany; (M.S.); (A.P.); (N.S.)
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6
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Zdarta J, Jesionowski T, Pinelo M, Meyer AS, Iqbal HMN, Bilal M, Nguyen LN, Nghiem LD. Free and immobilized biocatalysts for removing micropollutants from water and wastewater: Recent progress and challenges. BIORESOURCE TECHNOLOGY 2022; 344:126201. [PMID: 34710611 DOI: 10.1016/j.biortech.2021.126201] [Citation(s) in RCA: 36] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2021] [Revised: 10/17/2021] [Accepted: 10/20/2021] [Indexed: 02/05/2023]
Abstract
Enzymatic conversion of micropollutants into less-toxic derivatives is an important bioremediation strategy. This paper aims to critically review the progress in water and wastewater treatment by both free and immobilized enzymes presenting this approach as highly efficient and performed under environmentally benign and friendly conditions. The review also summarises the effects of inorganic and organic wastewater matrix constituents on enzymatic activity and degradation efficiency of micropollutants. Finally, application of enzymatic reactors facilitate continuous treatment of wastewater and obtaining of pure final effluents. Of a particular note, enzymatic treatment of micropollutants from wastewater has been mostly reported by laboratory scale studies. Thus, this review also highlights key research gaps of the existing techniques and provides future perspectives to facilitate the transfer of the lab-scale solutions to a larger scale and to improve operationability of biodegradation processes.
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Affiliation(s)
- Jakub Zdarta
- Institute of Chemical Technology and Engineering, Faculty of Chemical Technology, Poznan University of Technology, Berdychowo, PL-60965 Poznan, Poland.
| | - Teofil Jesionowski
- Institute of Chemical Technology and Engineering, Faculty of Chemical Technology, Poznan University of Technology, Berdychowo, PL-60965 Poznan, Poland
| | - Manuel Pinelo
- Process and Systems Engineering Centre, Department of Chemical and Biochemical Engineering, Technical University of Denmark, Søltofts Plads, DK-2800 Kongens Lyngby, Denmark
| | - Anne S Meyer
- Section for Protein Chemistry and Enzyme Technology, Department of Biotechnology and Biomedicine, Technical University of Denmark, Søltofts Plads, DK-2800 Kongens Lyngby, Denmark
| | - Hafiz M N Iqbal
- Tecnologico de Monterrey, School of Engineering and Sciences, Monterrey 64849, Mexico
| | - Muhammad Bilal
- School of Life Science and Food Engineering, Huaiyin Institute of Technology, Huaian 223003, China
| | - Luong N Nguyen
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, NSW 2007, Australia
| | - Long D Nghiem
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, NSW 2007, Australia
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7
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Gu Y, Yuan L, Jia L, Xue P, Yao H. Recent developments of a co-immobilized laccase-mediator system: a review. RSC Adv 2021; 11:29498-29506. [PMID: 35479547 PMCID: PMC9040808 DOI: 10.1039/d1ra05104k] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Accepted: 08/25/2021] [Indexed: 12/13/2022] Open
Abstract
The laccase-mediator is a promising biocatalyst with many possible applications, including bioremediation, chemical synthesis, biobleaching of paper pulp, biosensing, textile finishing and wine stabilization. The immobilization of laccase and the mediator offers several improvements for laccase-mediator system applications because the storage and operational stabilities are frequently enhanced. Moreover, the reusability of the immobilized laccase and mediator represents a great advantage compared with the free laccase and mediator. In this work, we review the methods of co-immobilization of the laccase-mediator system for the first time systematically and comprehensively. In addition, we discuss the different methodologies of laccase and mediator immobilization that have been reported.
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Affiliation(s)
- Yaohua Gu
- Key Laboratory of Environmental Factors and Chronic Disease Control, School of Public Health and Management, Ningxia Medical University Yinchuan 750004 China
| | - Lin Yuan
- Key Laboratory of Environmental Factors and Chronic Disease Control, School of Public Health and Management, Ningxia Medical University Yinchuan 750004 China
| | - Leina Jia
- Key Laboratory of Environmental Factors and Chronic Disease Control, School of Public Health and Management, Ningxia Medical University Yinchuan 750004 China
| | - Ping Xue
- College of Chemistry & Chemical Engineering, Ningxia University Yinchuan 750021 China
| | - Huiqin Yao
- School of Basic Medical Sciences, Ningxia Medical University Yinchuan 750004 China
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8
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Chiadò A, Bosco F, Bardelli M, Simonelli L, Pedotti M, Marmo L, Varani L. Rational engineering of the lccβ T. versicolor laccase for the mediator-less oxidation of large polycyclic aromatic hydrocarbons. Comput Struct Biotechnol J 2021; 19:2213-2222. [PMID: 33995914 PMCID: PMC8099718 DOI: 10.1016/j.csbj.2021.03.017] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Revised: 03/08/2021] [Accepted: 03/12/2021] [Indexed: 01/10/2023] Open
Abstract
Computational-assisted protein engineering of the binding pocket of laccases. Mutants have activity increased up to ~ 300% in a broader pH range compared to the WT. Enhanced activity towards bulky PAHs in comparison to the WT enzyme. Ability to oxidize harmful PAH model compounds (dyes) that the WT enzyme cannot modify. Higher oxidation levels without mediators compared to the WT laccase with mediators.
Laccases are among the most sought-after biocatalyst for many green applications, from biosensors to pollution remedial, because they simply need oxygen from the air to oxidize and degrade a broad range of substrates. However, natural laccases cannot process large and toxic polycyclic aromatic hydrocarbons (PAHs) except in the presence of small molecules, called mediators, which facilitate the reaction but are inconvenient for practical on-field applications. Here we exploited structure-based protein engineering to generate rationally modified fungal laccases with increased ability to process bulky PAHs even in a mediator-less reaction. Computational simulations were used to estimate the impact of mutations in the enzymatic binding pocket on the ability to bind and oxidize a selected set of organic compounds. The most promising mutants were produced and their activity was evaluated by biochemical assays with phenolic and non-phenolic substrates. Mutant laccases engineered with a larger binding pocket showed enhanced activity (up to ~ 300% at pH 3.0) in a wider range of pH values (3.0–8.0) in comparison to the wild type enzyme. In contrast to the natural laccase, these mutants efficiently degraded bulky and harmful triphenylmethane dyes such as Ethyl Green (up to 91.64% after 24 h), even in the absence of mediators, with positive implications for the use of such modified laccases in many green chemistry processes (e.g. wastewater treatment).
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Affiliation(s)
- Alessandro Chiadò
- Department of Applied Science and Technology, Politecnico di Torino Corso, Duca degli Abruzzi 24, 10129 Torino, Italy
- Corresponding author.
| | - Francesca Bosco
- Department of Applied Science and Technology, Politecnico di Torino Corso, Duca degli Abruzzi 24, 10129 Torino, Italy
| | - Marco Bardelli
- Institute for Research in Biomedicine, Università della Svizzera Italiana, Via Vincenzo Vela 6, 6500, Bellinzona, Switzerland
| | - Luca Simonelli
- Institute for Research in Biomedicine, Università della Svizzera Italiana, Via Vincenzo Vela 6, 6500, Bellinzona, Switzerland
| | - Mattia Pedotti
- Institute for Research in Biomedicine, Università della Svizzera Italiana, Via Vincenzo Vela 6, 6500, Bellinzona, Switzerland
| | - Luca Marmo
- Department of Applied Science and Technology, Politecnico di Torino Corso, Duca degli Abruzzi 24, 10129 Torino, Italy
| | - Luca Varani
- Institute for Research in Biomedicine, Università della Svizzera Italiana, Via Vincenzo Vela 6, 6500, Bellinzona, Switzerland
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Zhang Y, Ren J, Wang Q, Wang S, Li S, Li H. Oxidation characteristics and degradation potential of a dye-decolorizing peroxidase from Bacillus amyloliquefaciens for crystal violet dye. Biochem Eng J 2021. [DOI: 10.1016/j.bej.2021.107930] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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10
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Zhou Q, Guo M, Ni K, Kerton FM. Construction of supramolecular laccase enzymes and understanding of catalytic dye degradation using multispectral and molecular docking approaches. REACT CHEM ENG 2021. [DOI: 10.1039/d1re00111f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A non-covalent supramolecular enzyme system which was successfully constructed by non-covalent interaction of enzyme with substrates analogs can effectively recognize and degrade 13 kinds of dyes.
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Affiliation(s)
- Qingteng Zhou
- College of Engineering, Zhejiang A&F University, Hangzhou, Zhejiang 311300, China
| | - Ming Guo
- College of Engineering, Zhejiang A&F University, Hangzhou, Zhejiang 311300, China
- College of Science, Zhejiang A&F University, Hangzhou, Zhejiang 311300, China
| | - Kaijie Ni
- College of Science, Zhejiang A&F University, Hangzhou, Zhejiang 311300, China
| | - Francesca M. Kerton
- Department of Chemistry, Memorial University of Newfoundland, St. John's, NL, Canada A1B 3X7
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11
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Yang J, Zhang Y, Wang S, Li S, Wang Y, Wang S, Li H. Biodegradation of crystal violet mediated by CotA from Bacillus amyloliquefaciens. J Biosci Bioeng 2020; 130:347-351. [DOI: 10.1016/j.jbiosc.2020.05.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Revised: 05/06/2020] [Accepted: 05/07/2020] [Indexed: 01/26/2023]
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12
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A Novel Approach in Crude Enzyme Laccase Production and Application in Emerging Contaminant Bioremediation. Processes (Basel) 2020. [DOI: 10.3390/pr8060648] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Laccase enzyme from white-rot fungi is a potential biocatalyst for the oxidation of emerging contaminants (ECs), such as pesticides, pharmaceuticals and steroid hormones. This study aims to develop a three-step platform to treat ECs: (i) enzyme production, (ii) enzyme concentration and (iii) enzyme application. In the first step, solid culture and liquid culture were compared. The solid culture produced significantly more laccase than the liquid culture (447 vs. 74 µM/min after eight days), demonstrating that white rot fungi thrived on a solid medium. In the second step, the enzyme was concentrated 6.6 times using an ultrafiltration (UF) process, resulting in laccase activity of 2980 µM/min. No enzymatic loss due to filtration and membrane adsorption was observed, suggesting the feasibility of the UF membrane for enzyme concentration. In the third step, concentrated crude enzyme was applied in an enzymatic membrane reactor (EMR) to remove a diverse set of ECs (31 compounds in six groups). The EMR effectively removed of steroid hormones, phytoestrogen, ultraviolet (UV) filters and industrial chemical (above 90%). However, it had low removal of pesticides and pharmaceuticals.
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13
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Xu KZ, Ma H, Wang YJ, Cai YJ, Liao XR, Guan ZB. Extracellular expression of mutant CotA-laccase SF in Escherichia coli and its degradation of malachite green. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2020; 193:110335. [PMID: 32088549 DOI: 10.1016/j.ecoenv.2020.110335] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2019] [Revised: 02/10/2020] [Accepted: 02/13/2020] [Indexed: 06/10/2023]
Abstract
In this study, mutant CotA-laccase SF was successfully expressed in Escherichia coli by co-expression with phospholipase C. The optimized extracellular expression of CotA-laccase SF was 1257.22 U/L. Extracellularly expressed CotA-laccase SF exhibits enzymatic properties similar to intracellular CotA-laccase SF. CotA-laccase SF could decolorize malachite green (MG) under neutral and alkaline conditions. The Km and kcat values of CotA-laccase SF to MG were 39.6 mM and 18.36 s-1. LC-MS analysis of degradation products showed that MG was finally transformed into 4-aminobenzophenone and 4-aminophenol by CotA-laccase. The toxicity experiment of garlic root tip cell showed that the toxicity of MG metabolites decreased. In summary, CotA-laccase SF had a good application prospect for degrading malachite green.
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Affiliation(s)
- Kai-Zhong Xu
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, PR China
| | - Hui Ma
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, PR China
| | - Ya-Jing Wang
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, PR China
| | - Yu-Jie Cai
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, PR China
| | - Xiang-Ru Liao
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, PR China
| | - Zheng-Bing Guan
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, 214122, PR China.
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14
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Yuan H, Chen L, Cao Z, Hong FF. Enhanced decolourization efficiency of textile dye Reactive Blue 19 in a horizontal rotating reactor using strips of BNC-immobilized laccase: Optimization of conditions and comparison of decolourization efficiency. Biochem Eng J 2020. [DOI: 10.1016/j.bej.2020.107501] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/07/2022]
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15
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Environmentally Friendly and Recyclable Natural-Mediator-Modified Magnetic Nanoparticles for Laccase-Catalyzed Decolorization. J CHEM-NY 2019. [DOI: 10.1155/2019/4140565] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The high cost, potential toxicity, and possible enzyme inhibition ability of artificial mediators have limited the large-scale application of laccase (Lac)/mediator systems. Here, sinapic acid (SA), a natural mediator, was covalently attached to amino-functionalized magnetic nanoparticles (MNPs) via amide bond formation. The as-prepared SA@MNPs were characterized by Fourier-transform infrared spectroscopy, scanning electron microscopy, cyclic voltammetry, and thermogravimetric analysis. The SA@MNPs were then applied to evaluate the activity of the immobilized mediator for Lac-catalyzed dye decolorization using indigo carmine (IC) as a model dye. When SA and SA@MNPs were used as Lac mediators, IC decolorization yields of ∼93% and 96%, respectively, were obtained after 60 min. Moreover, SA@MNPs exhibited an IC decolorization yield of ∼90% after being reused for 8 cycles. The Lac/SA@MNP system was shown to degrade IC by breaking down the chromophoric group. The easy recyclability, good reusability, nontoxicity, and relatively low cost of SA@MNPs make this immobilized natural mediator a promising tool for dye treatment.
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16
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Zhuo R, Zhang J, Yu H, Ma F, Zhang X. The roles of Pleurotus ostreatus HAUCC 162 laccase isoenzymes in decolorization of synthetic dyes and the transformation pathways. CHEMOSPHERE 2019; 234:733-745. [PMID: 31234090 DOI: 10.1016/j.chemosphere.2019.06.113] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Revised: 04/11/2019] [Accepted: 06/14/2019] [Indexed: 05/07/2023]
Abstract
Fungal laccases have shown great potential in industrial and environmental applications. They are generally produced as laccase isoenzymes. Thus, to further study the properties of different laccase isoenzymes and their performance in bio-remediation is essential for a deep understanding of laccase function and application. In this study, three Pleurotus ostreatus HAUCC 162 laccase isoenzymes were heterologously expressed, and the effects of different inhibitors, metal ions, and organic solvents on the activity of recombinant laccases were evaluated. In the dye decolorization test, LACC6 showed the highest ability to remove Malachite green (MG), Remazol Brilliant Blue R (RBBR), Bromophenol blue (BB), and Methyl orange (MO) among the three recombinant laccases. Removal rates within 24 h were 91.5%, 84.9%, 79.1%, and 73.1% for MG (100 mg/L), RBBR (100 mg/L), BB (100 mg/L), and MO (100 mg/L), respectively. The MG and RBBR transformation pathways were proposed by using High Performance Liquid Chromatography-Mass Spectrometry (LC-MS) analysis. Based on the results of this work, the production of recombinant LACC6 or improving the portion of LACC6 in the crude extracellular laccase may advance synthetic dye removal.
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Affiliation(s)
- Rui Zhuo
- Key Laboratory of Molecular Biophysics of MOE, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, 430074, PR China; Institute of Plant and Microbiology, College of Biology, Hunan University, Changsha, 410082, PR China
| | - Jingwen Zhang
- Key Laboratory of Molecular Biophysics of MOE, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, 430074, PR China
| | - Hongbo Yu
- Key Laboratory of Molecular Biophysics of MOE, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, 430074, PR China
| | - Fuying Ma
- Key Laboratory of Molecular Biophysics of MOE, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, 430074, PR China.
| | - Xiaoyu Zhang
- Key Laboratory of Molecular Biophysics of MOE, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, 430074, PR China.
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17
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Cen Y, Liu Y, Xue Y, Zheng Y. Immobilization of Enzymes in/on Membranes and their Applications. Adv Synth Catal 2019. [DOI: 10.1002/adsc.201900439] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Yu‐Ke Cen
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and BioengineeringZhejiang University of Technology Hangzhou 310014 People's Republic of China
- Engineering Research Center of Bioconversion and Biopurification of Ministry of EducationZhejiang University of Technology Hangzhou 310014 People's Republic of China
| | - Yu‐Xiao Liu
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and BioengineeringZhejiang University of Technology Hangzhou 310014 People's Republic of China
- Engineering Research Center of Bioconversion and Biopurification of Ministry of EducationZhejiang University of Technology Hangzhou 310014 People's Republic of China
| | - Ya‐Ping Xue
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and BioengineeringZhejiang University of Technology Hangzhou 310014 People's Republic of China
- Engineering Research Center of Bioconversion and Biopurification of Ministry of EducationZhejiang University of Technology Hangzhou 310014 People's Republic of China
| | - Yu‐Guo Zheng
- Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and BioengineeringZhejiang University of Technology Hangzhou 310014 People's Republic of China
- Engineering Research Center of Bioconversion and Biopurification of Ministry of EducationZhejiang University of Technology Hangzhou 310014 People's Republic of China
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18
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Huang W, Yang H, Zhang S. Acetylacetone extends the working life of laccase in enzymatic transformation of malachite green by interfering with a key intermediate. JOURNAL OF HAZARDOUS MATERIALS 2019; 366:520-528. [PMID: 30572291 DOI: 10.1016/j.jhazmat.2018.12.028] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Revised: 12/08/2018] [Accepted: 12/10/2018] [Indexed: 06/09/2023]
Abstract
The potential of acetylacetone (AA) as a mediator of laccase has been tested in the enzymatic transformation of malachite green (MG). AA inhibited the laccase-induced transformation of MG at the beginning of incubation but extended the working life of laccase in long runs. To elucidate the underlying mechanisms, the transformation of MG in the laccase-AA system was systematically investigated. The inhibition of AA on the enzymatic transformation of MG conformed to the partial mixed model. The transformation of N,N,N',N'-tetramethyl-1,1'-biphenyl-4,4'-diamine (NTB) was identified as the rate-controlling step in the laccase system. The generated NTB was oxidized to NTB+ by laccase, which acted as a redox mediator to accelerate the transformation of MG. The addition of AA to the enzymatic system quenched the NTB+ by forming an intermediate complex of AA-NTB. This quenching reaction led to two contrary effects: the acceleration caused by NTB+ in the enzymatic transformation of MG was inhibited whereas the formation of AA-NTB complex enhanced the further transformation at the later stage. As a result, less laccase was consumed, which explained the extended working life of laccase in the long runs. The understanding of these mechanisms are helpful for the better use of laccase as a green biocatalyst.
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Affiliation(s)
- Wenguang Huang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, China
| | - Hua Yang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, China
| | - Shujuan Zhang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, China.
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19
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Wen X, Du C, Wan J, Zeng G, Huang D, Yin L, Deng R, Tan S, Zhang J. Immobilizing laccase on kaolinite and its application in treatment of malachite green effluent with the coexistence of Cd (П). CHEMOSPHERE 2019; 217:843-850. [PMID: 30458419 DOI: 10.1016/j.chemosphere.2018.11.073] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Revised: 10/23/2018] [Accepted: 11/11/2018] [Indexed: 05/21/2023]
Abstract
Malachite green effluent with the Coexistence of Cd (П) was efficiently decolorized by kaolinite-laccase (Kaolin-Lac). Laccase from Trametes versicolor was immobilized onto the kaolinite through physical adsorption contact. The optimal conditions were 180 min of immobilization time and 0.8 mg/mL of enzyme solution. Kaolin-Lac could obtain a loading efficiency of 88.22%, a loading capacity of 12.25 mg/g, and the highest activity of 839.01 U/g. Moreover, the process of immobilization increased its pH stability and operational stability. Kaolin-Lac retained above 50% of the original activity and nearly 80% decolorization for MG after 5 cycles. In the presence of 3, 5-Dimethoxy-4-hydroxybenzaldehyde (SA), Kaolin-Lac could degrade over 98% of malachite green. The coexistence of Cd (П) was beneficial to the decolorization of malachite green by Kaolin-Lac. The structural and morphological features of kaolinite, Kaolin-Lac and Kaolin-Lac after degradation were determined by scanning electron microscopy-energy spectrum analysis (SEM-EDS) and Fourier transform infrared spectroscopy (FTIR). Cadmium appeared on the Kaolin-Lac after degradation. After immobilization and degradation, the surface groups on kaolinite were changed. Kaolin-Lac showed its more potential continuous employment than free laccase in practical malachite green dyes effluent mixed with Cd (П).
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Affiliation(s)
- Xiaofeng Wen
- College of Environmental Science and Engineering, Hunan University and Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, PR China.
| | - Chunyan Du
- School of Hydraulic Engineering, Changsha University of Science &Technology, Changsha 410114, PR China; Key Laboratory of Water-Sediment Sciences and Water Disaster Prevention of Hunan Province, Changsha 410114, PR China.
| | - Jia Wan
- College of Environmental Science and Engineering, Hunan University and Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, PR China.
| | - Guangming Zeng
- College of Environmental Science and Engineering, Hunan University and Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, PR China.
| | - Danlian Huang
- College of Environmental Science and Engineering, Hunan University and Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, PR China.
| | - Lingshi Yin
- School of Hydraulic Engineering, Changsha University of Science &Technology, Changsha 410114, PR China; Key Laboratory of Water-Sediment Sciences and Water Disaster Prevention of Hunan Province, Changsha 410114, PR China.
| | - Rui Deng
- College of Environmental Science and Engineering, Hunan University and Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, PR China.
| | - Shiyang Tan
- School of Hydraulic Engineering, Changsha University of Science &Technology, Changsha 410114, PR China; Key Laboratory of Water-Sediment Sciences and Water Disaster Prevention of Hunan Province, Changsha 410114, PR China.
| | - Jinfan Zhang
- School of Hydraulic Engineering, Changsha University of Science &Technology, Changsha 410114, PR China; Key Laboratory of Water-Sediment Sciences and Water Disaster Prevention of Hunan Province, Changsha 410114, PR China.
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20
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Huang J, Yang Y, Wang Y, Zhang M, Liu Y. Immobilization of a Laccase/2,2'-azino-bis-(3-ethylbenzothiazoline)-6-sulfonic Acid System to Layered Double Hydroxide/Alginate Biohybrid Beads for Biodegradation of Malachite Green Dye. BIOMED RESEARCH INTERNATIONAL 2018; 2018:5471961. [PMID: 30345302 PMCID: PMC6174817 DOI: 10.1155/2018/5471961] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Revised: 08/06/2018] [Accepted: 09/05/2018] [Indexed: 02/02/2023]
Abstract
The application of laccase-mediator-based catalysis is limited owing to the high cost of laccases and mediators and the potential toxicity of free mediators. Here, a novel biocatalyst (Im-LMS) was fabricated by immobilizing both laccase and a mediator (2,2'-azino-bis-[3-ethylbenzothiazoline]-6-sulfonic acid) on layered double hydroxide/alginate biohybrid beads. The catalytic activity of Im-LMS was evaluated for dye decolorization using malachite green. The decolorization yields of malachite green by Im-LMS and the free laccase-mediator system were 92% within 120 min and 90% within 90 min. Malachite green solution was detoxified completely after biodegradation by Im-LMS. Following eight reuse cycles of Im-LMS for dye treatment, a decolorization yield of 79% was obtained. The activity of Im-LMS was almost completely stable after being stored for 10 days. The recyclability and stability of Im-LMS will be helpful for reducing the running cost and potential toxicity associated with mediators to facilitate practical applications.
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Affiliation(s)
- Juan Huang
- School of Life Sciences and Technology, Xinxiang Medical University, Jinsui Avenue 601, Xinxiang, Henan 453003, China
| | - Yun Yang
- School of Basic Medical Sciences, Xinxiang Medical University, Jinsui Avenue 601, Xinxiang, Henan 453003, China
| | - Yaokun Wang
- School of Basic Medical Sciences, Xinxiang Medical University, Jinsui Avenue 601, Xinxiang, Henan 453003, China
| | - Mingyang Zhang
- School of Basic Medical Sciences, Xinxiang Medical University, Jinsui Avenue 601, Xinxiang, Henan 453003, China
| | - Youxun Liu
- School of Basic Medical Sciences, Xinxiang Medical University, Jinsui Avenue 601, Xinxiang, Henan 453003, China
- Key Laboratory of molecular medicine of Xinxiang, Jinsui Avenue 601, Xinxiang, Henan 453003, China
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21
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Decolourization and detoxification of monoazo dyes by laccase from the white-rot fungus Trametes versicolor. J Biotechnol 2018; 285:84-90. [PMID: 30171927 DOI: 10.1016/j.jbiotec.2018.08.011] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Revised: 08/21/2018] [Accepted: 08/23/2018] [Indexed: 01/25/2023]
Abstract
The decolourization and detoxification of azo dyes (Orange 2, Acid Orange 6) by fungal laccase from Trametes versicolor were evaluated. For laccase catalysed reaction, the azonaphthol Orange 2, with 72.8% decolourization, was degraded more rapidly than the azobenzene Acid Orange 6, with 45.3%. The presence of hydroxyl group at o-position to azo bond in the structure of Orange 2 was more preferable than the presence of two hydroxyl groups at o- and p-positions to azo bond in Acid Orange 6. Although the laccase treatment was more effective for the Orange 2 decolourization, the toxicity of both monoazo dye solutions became less toxic for the prokaryote growth. The phytotoxicity of Orange 2 and Acid Orange 6 solutions after laccase treatment was decreased in the range of 41.2-64.3 %. Also, the photoxicity, as measured by the production of chlorophylls a and b by Chlorella vulgaris and Microcystis aeruginosa, was decreased by laccase treatment of selected monoazo dyes. Our results show that different dyes can be decolorized and detoxified by laccase from T. versicolor in a single step.
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22
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Congo Red Decolorization and Detoxification by Aspergillus niger: Removal Mechanisms and Dye Degradation Pathway. BIOMED RESEARCH INTERNATIONAL 2018; 2018:3049686. [PMID: 30175122 PMCID: PMC6106729 DOI: 10.1155/2018/3049686] [Citation(s) in RCA: 76] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Accepted: 07/25/2018] [Indexed: 11/17/2022]
Abstract
Congo red is one of the best known and used azo dyes which has two azo bonds (-N=N-) chromophore in its molecular structure. Its structural stability makes it highly toxic and resistant to biodegradation. The objective of this study was to assess the congo red biodegradation and detoxification by Aspergillus niger. The effects of pH, initial dye concentration, temperature, and shaking speed on the decolorization rate and enzymes production were studied. The maximum decolorization was correlated with lignin peroxidase and manganese peroxidase production. Above 97% were obtained when 2 g mycelia were incubated at pH 5, in presence of 200 mg/L of dye during 6 days at 28°C and under 120 to 150 rpm shaking speed. The degraded metabolites were characterized by using LC-MS/MS analyses and the biodegradation mechanism was also studied. Congo red bioconversion formed degradation metabolites mainly by peroxidases activities, i.e., the sodium naphthalene sulfonate (m/z = 227) and the cycloheptadienylium (m/z = 91). Phytotoxicity and microtoxicity tests confirmed that degradation metabolites were less toxic than original dye.
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23
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Miao M, Yin W, Wang L, Chen Z, Xu J, Ren H. Transition-Metal-Free Arylation and Alkylation of Diarylmethyl p-Tolyl Sulfones with Zinc Reagents. J Org Chem 2018; 83:10602-10612. [DOI: 10.1021/acs.joc.8b01428] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Maozhong Miao
- Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou, Zhejiang 310018, P. R. China
| | - Wenguang Yin
- Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou, Zhejiang 310018, P. R. China
| | - Lei Wang
- Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou, Zhejiang 310018, P. R. China
| | - Zhengkai Chen
- Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou, Zhejiang 310018, P. R. China
| | - Jianfeng Xu
- Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou, Zhejiang 310018, P. R. China
| | - Hongjun Ren
- Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou, Zhejiang 310018, P. R. China
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24
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Zhang X, Wang M, Lin L, Xiao G, Tang Z, Zhu X. Synthesis of novel laccase-biotitania biocatalysts for malachite green decolorization. J Biosci Bioeng 2018; 126:69-77. [PMID: 29567373 DOI: 10.1016/j.jbiosc.2018.01.021] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2017] [Revised: 01/19/2018] [Accepted: 01/30/2018] [Indexed: 12/12/2022]
Abstract
Biomimetic mineralization has emerged as a novel tool for generating excellent supports for enzyme stabilization. In this work, protamine was used to induce titanium (IV) bis(ammonium lactato) dihydroxide (Ti-BALDH) into titania nanoparticles. This biomimetic titanification process was adopted for laccase immobilization. Laccase-biotitania biocatalyst was prepared and the effect of different parameters (buffer solution, titania precursor concentration, protamine concentration, and enzyme loading) on the encapsulation efficiency and recovery of laccase were evaluated. Compared with free laccase, the thermal and pH stability of immobilized laccase were improved significantly. In addition, laccase loaded on titania was effective at enhancing its storage stability. After seven consecutive cycles, the immobilized laccase still retained 51% of its original activity. Finally, laccase-biotitania biocatalysts showed good performance on decolorization of malachite green (MG), which can be attributed to an adsorption and degradation effect. The intermediates of the MG degradation were identified by gas chromatography-mass spectrometry (GC-MS) analysis, and the most probable degradation pathway was proposed. This study provides deeper understanding of the laccase-biotitania particles as a fast biocatalyst for MG decolorization.
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Affiliation(s)
- Xinying Zhang
- College of Environment and Resources, Fuzhou University, Fuzhou, Fujian 350108, PR China; Research Institute of Photocatalysis, State Key Laboratory of Photocatalysis on Energy and Environment, Fuzhou University, Fuzhou 350002, China
| | - Meiyin Wang
- College of Environment and Resources, Fuzhou University, Fuzhou, Fujian 350108, PR China
| | - Linlin Lin
- College of Environment and Resources, Fuzhou University, Fuzhou, Fujian 350108, PR China
| | - Gao Xiao
- College of Environment and Resources, Fuzhou University, Fuzhou, Fujian 350108, PR China
| | - Zhenping Tang
- College of Environment and Resources, Fuzhou University, Fuzhou, Fujian 350108, PR China
| | - Xuefeng Zhu
- Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, 500 Dongchuan Rd., Shanghai 200241, PR China; Section Sanitary Engineering, Department of Water Management, Faculty of Civil Engineering and GeoSciences, Delft University of Technology, 2628CN Delft, The Netherlands.
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25
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Vats A, Mishra S. Identification and evaluation of bioremediation potential of laccase isoforms produced by Cyathus bulleri on wheat bran. JOURNAL OF HAZARDOUS MATERIALS 2018; 344:466-479. [PMID: 29096258 DOI: 10.1016/j.jhazmat.2017.10.043] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Revised: 10/17/2017] [Accepted: 10/21/2017] [Indexed: 06/07/2023]
Abstract
Multiplicity in laccases among lignin degrading fungal species is of interest as it confers the ability to degrade several types of lignocellulosics. The combination of laccases produced on such substrates could be beneficial for treatment of complex aromatics, including dyes. In this study, we report on production of high units (679.6Ug-1 substrate) of laccase on solid wheat bran (WB) by Cyathus bulleri. Laccase, purified from the culture filtrates of WB grown fungus, was effective for oxidation of veratryl alcohol, Reactive blue 21 and textile effluent without assistance of externally added mediators. De novo sequencing of the 'purified' laccase lead to identification of several peptides that originated from different laccase genes. Transcriptome analysis of the fungus, cultivated on WB, confirmed presence of 8 isozymes, that were re-amplified and sequenced from the cDNA prepared from WB grown fungus. The 8 isozymes were grouped into 3 classes, based on their sequence relationship with other basidiomycete laccases. The isoforms produced on WB decolorized (by ∼57%) and degraded textile effluent far more effectively, compared to laccase obtained from Basal salt cultivated fungus. The decolorization and degradation was also accompanied by more than 95% reduction in phytotoxicity.
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Affiliation(s)
- Arpita Vats
- Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology Delhi, Hauz-Khas, New Delhi 110016, India
| | - Saroj Mishra
- Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology Delhi, Hauz-Khas, New Delhi 110016, India.
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26
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Singh J, Saharan V, Kumar S, Gulati P, Kapoor RK. Laccase grafted membranes for advanced water filtration systems: a green approach to water purification technology. Crit Rev Biotechnol 2017; 38:883-901. [DOI: 10.1080/07388551.2017.1417234] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Jagdeep Singh
- Enzyme Biotechnology and Waste-water Treatment Laboratory, Department of Microbiology, Maharshi Dayanand University, Rohtak, Haryana, India
| | - Vicky Saharan
- Enzyme Biotechnology and Waste-water Treatment Laboratory, Department of Microbiology, Maharshi Dayanand University, Rohtak, Haryana, India
| | - Sanjay Kumar
- Enzyme Biotechnology and Waste-water Treatment Laboratory, Department of Microbiology, Maharshi Dayanand University, Rohtak, Haryana, India
| | - Pooja Gulati
- Enzyme Biotechnology and Waste-water Treatment Laboratory, Department of Microbiology, Maharshi Dayanand University, Rohtak, Haryana, India
| | - Rajeev Kumar Kapoor
- Enzyme Biotechnology and Waste-water Treatment Laboratory, Department of Microbiology, Maharshi Dayanand University, Rohtak, Haryana, India
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27
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Cantele C, Vilasboa J, dos Reis EE, Fontana RC, Camassola M, Dillon AJP. Synthetic dye decolorization by Marasmiellus palmivorus : Simultaneous cultivation and high laccase-crude broth treatment. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2017. [DOI: 10.1016/j.bcab.2017.10.025] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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28
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Liu Y, Geng Y, Yan M, Huang J. Stable ABTS Immobilized in the MIL-100(Fe) Metal-Organic Framework as an Efficient Mediator for Laccase-Catalyzed Decolorization. Molecules 2017; 22:molecules22060920. [PMID: 28574450 PMCID: PMC6152645 DOI: 10.3390/molecules22060920] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Revised: 05/31/2017] [Accepted: 05/31/2017] [Indexed: 11/22/2022] Open
Abstract
The successful encapsulation of 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS), a well-known laccase mediator, within a mesoporous metal-organic framework sample (i.e., MIL-100(Fe)) was achieved using a one-pot hydrothermal synthetic method. The as-prepared ABTS@MIL-100(Fe) was characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, nitrogen sorption, and cyclic voltammetry (CV). Our ABTS@MIL-100(Fe)-based electrode exhibited an excellent electrochemical response, indicating that MIL-100(Fe) provides an appropriate microenvironment for the immobilization and electroactivity of ABTS molecules. ABTS@MIL-100(Fe) was then evaluated as an immobilized laccase mediator for dye removal using indigo carmine (IC) as a model dye. Through the application of laccase in combination with a free (ABTS) or immobilized (ABTS@MIL-100(Fe)) mediator, decolorization yields of 95% and 94%, respectively, were obtained for IC after 50 min. In addition, following seven reuse cycles of ABTS@MIL-100(Fe) for dye treatment, a decolorization yield of 74% was obtained. Dye decolorization occurred through the breakdown of the chromophoric group by the Laccase/ABTS@MIL-100(Fe) system, and a catalytic mechanism was proposed. We therefore expect that the stability, reusability, and validity of ABTS@MIL-100(Fe) as a laccase mediator potentially render it a promising tool for dye removal, in addition to reducing the high running costs and potential toxicity associated with synthetic mediators.
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Affiliation(s)
- Youxun Liu
- School of Basic Medical Sciences, Xinxiang Medical University, Jinsui Avenue 601, Xinxiang 453003, Henan, China.
- Henan Collaborative Innovation Center of Molecular Diagnostics and Laboratory Medicine, Jinsui Avenue 601, Xinxiang 453003, Henan, China.
| | - Yuanyuan Geng
- School of Basic Medical Sciences, Xinxiang Medical University, Jinsui Avenue 601, Xinxiang 453003, Henan, China.
| | - Mingyang Yan
- School of Basic Medical Sciences, Xinxiang Medical University, Jinsui Avenue 601, Xinxiang 453003, Henan, China.
| | - Juan Huang
- School of Basic Medical Sciences, Xinxiang Medical University, Jinsui Avenue 601, Xinxiang 453003, Henan, China.
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29
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Yang J, Li W, Ng TB, Deng X, Lin J, Ye X. Laccases: Production, Expression Regulation, and Applications in Pharmaceutical Biodegradation. Front Microbiol 2017; 8:832. [PMID: 28559880 PMCID: PMC5432550 DOI: 10.3389/fmicb.2017.00832] [Citation(s) in RCA: 143] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Accepted: 04/24/2017] [Indexed: 01/08/2023] Open
Abstract
Laccases are a family of copper-containing oxidases with important applications in bioremediation and other various industrial and biotechnological areas. There have been over two dozen reviews on laccases since 2010 covering various aspects of this group of versatile enzymes, from their occurrence, biochemical properties, and expression to immobilization and applications. This review is not intended to be all-encompassing; instead, we highlighted some of the latest developments in basic and applied laccase research with an emphasis on laccase-mediated bioremediation of pharmaceuticals, especially antibiotics. Pharmaceuticals are a broad class of emerging organic contaminants that are recalcitrant and prevalent. The recent surge in the relevant literature justifies a short review on the topic. Since low laccase yields in natural and genetically modified hosts constitute a bottleneck to industrial-scale applications, we also accentuated a genus of laccase-producing white-rot fungi, Cerrena, and included a discussion with regards to regulation of laccase expression.
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Affiliation(s)
- Jie Yang
- Fujian Key Laboratory of Marine Enzyme Engineering, Fuzhou UniversityFujian, China
| | - Wenjuan Li
- Fujian Key Laboratory of Marine Enzyme Engineering, Fuzhou UniversityFujian, China
| | - Tzi Bun Ng
- Faculty of Medicine, School of Biomedical Sciences, The Chinese University of Hong KongShatin, Hong Kong
| | - Xiangzhen Deng
- Fujian Key Laboratory of Marine Enzyme Engineering, Fuzhou UniversityFujian, China
| | - Juan Lin
- Fujian Key Laboratory of Marine Enzyme Engineering, Fuzhou UniversityFujian, China
| | - Xiuyun Ye
- Fujian Key Laboratory of Marine Enzyme Engineering, Fuzhou UniversityFujian, China
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30
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Vats A, Mishra S. Decolorization of complex dyes and textile effluent by extracellular enzymes of Cyathus bulleri cultivated on agro-residues/domestic wastes and proposed pathway of degradation of Kiton blue A and reactive orange 16. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2017; 24:11650-11662. [PMID: 28324257 DOI: 10.1007/s11356-017-8802-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Accepted: 03/10/2017] [Indexed: 06/06/2023]
Abstract
In this study, the white-rot fungus Cyathus bulleri was cultivated on low-cost agro-residues, namely wheat bran (WB), wheat straw (WS), and domestic waste orange peel (OP) for production of ligninolytic enzymes. Of the three substrates, WB and OP served as good materials for the production of laccase with no requirement of additional carbon or nitrogen source. Specific laccase activity of 94.4 U mg-1 extracellular protein and 21.01 U mg-1 protein was obtained on WB and OP, respectively. Maximum decolorization rate of 13.6 μmol h-1 U-1 laccase for reactive black 5 and 22.68 μmol h-1 U-1 laccase for reactive orange 16 (RO) was obtained with the WB culture filtrate, and 11.7 μmol h-1 U-1 laccase for reactive violet 5 was observed with OP culture filtrate. Importantly, Kiton blue A (KB), reported not to be amenable to enzymatic degradation, was degraded by culture filtrate borne activities. Products of degradation of KB and RO were identified by mass spectrometry, and a pathway of degradation proposed. WB-grown culture filtrate decolorized and detoxified real and simulated textile effluents by about 40%. The study highlights the use of inexpensive materials for the production of enzymes effective on dyes and effluents.
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Affiliation(s)
- Arpita Vats
- Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology Delhi, New Delhi, 110016, India
| | - Saroj Mishra
- Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology Delhi, New Delhi, 110016, India.
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31
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Asgher M, Noreen S, Bilal M. Enhancing catalytic functionality of Trametes versicolor IBL-04 laccase by immobilization on chitosan microspheres. Chem Eng Res Des 2017. [DOI: 10.1016/j.cherd.2016.12.011] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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32
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Zhao Z, Feng Y, Shamsaei E, Song J, Wang H, He L. Highly stable enzymatic membrane for fast treatment of antibiotic-polluted water. J Memb Sci 2016. [DOI: 10.1016/j.memsci.2016.06.030] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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33
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Jin X, Yu X, Zhu G, Zheng Z, Feng F, Zhang Z. Conditions Optimizing and Application of Laccase-mediator System (LMS) for the Laccase-catalyzed Pesticide Degradation. Sci Rep 2016; 6:35787. [PMID: 27775052 PMCID: PMC5075893 DOI: 10.1038/srep35787] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Accepted: 10/06/2016] [Indexed: 11/24/2022] Open
Abstract
A high capacity of laccase from Trametes versicolor capable of degrading pesticides has been revealed. The conditions for degrading of five selected pesticides including chlorpyrifos, chlorothalonil, pyrimethanil, atrazine and isoproturon with the purified laccases from Trametes versicolor were optimized. The results showed that the optimum conditions for the highest activity were pH at 5.0 and temperature at 25 °C. The best mediators were violuric acid for pyrimethanil and isoproturon, vanillin for chlorpyrifos, and acetosyringone and HBT for chlorothalonil and atrazine, respectively. The laccase was found to be stable at a pH range from 5.0 to 7.0 and temperature from 25 to 30 °C. It was observed that each pesticide required a different laccase mediator concentration typically between 4.0-6.0 mmol/L. In the experiment, the degradation rates of pyrimethanil and isoproturon were significantly faster than those of chlorpyrifos, chlorothalonil and atrazine. For example, it was observed that pyrimethanil and isoproturon degraded up to nearly 100% after 24 hours while the other three pesticides just reached up 90% of degradation after 8 days of incubation.
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Affiliation(s)
- Xiaoting Jin
- Key Laboratory of Food Quality and Safety of Jiangsu Province/State Key Laboratory Breeding Base/Key Laboratory of Control Technology and Standard for Agro-product Safety and Quality, Ministry of Agriculture of P. R. China, Nanjing, 210014, China
| | - Xiangyang Yu
- Key Laboratory of Food Quality and Safety of Jiangsu Province/State Key Laboratory Breeding Base/Key Laboratory of Control Technology and Standard for Agro-product Safety and Quality, Ministry of Agriculture of P. R. China, Nanjing, 210014, China
| | - Guangyan Zhu
- Institute for the Control of Agrochemicals, Ministry of Agriculture of P. R. China, Beijing, 100125, China
| | - Zuntao Zheng
- Institute for the Control of Agrochemicals, Ministry of Agriculture of P. R. China, Beijing, 100125, China
| | - Fayun Feng
- Key Laboratory of Food Quality and Safety of Jiangsu Province/State Key Laboratory Breeding Base/Key Laboratory of Control Technology and Standard for Agro-product Safety and Quality, Ministry of Agriculture of P. R. China, Nanjing, 210014, China
| | - Zhiyong Zhang
- Key Laboratory of Food Quality and Safety of Jiangsu Province/State Key Laboratory Breeding Base/Key Laboratory of Control Technology and Standard for Agro-product Safety and Quality, Ministry of Agriculture of P. R. China, Nanjing, 210014, China
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Liu H, Zhou P, Wu X, Sun J, Chen S. Radical Scavenging by Acetone: A New Perspective to Understand Laccase/ABTS Inactivation and to Recover Redox Mediator. Molecules 2015; 20:19907-13. [PMID: 26556325 PMCID: PMC6332252 DOI: 10.3390/molecules201119672] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Revised: 10/27/2015] [Accepted: 10/28/2015] [Indexed: 12/02/2022] Open
Abstract
The biosynthetic utilization of laccase/mediator system is problematic because the use of organic cosolvent causes significant inhibition of laccase activity. This work explored how the organic cosolvent impacts on the laccase catalytic capacity towards 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) in aqueous solution. Effects of acetone on the kinetic constants of laccase were determined and the results showed Km and Vmax varied exponentially with increasing acetone content. Acetone as well as some other cosolvents could transform ABTS radicals into its reductive form. The content of acetone in media significantly affected the radical scavenging rates. Up to 95% of the oxidized ABTS was successfully recovered in 80% (v/v) acetone in 60 min. This allows ABTS to be recycled at least six times with 70%–75% of active radicals recovered after each cycle. This solvent-based recovery strategy may help improve the economic feasibility of laccase/ABTS system in biosynthesis.
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Affiliation(s)
- Hao Liu
- State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640, China.
| | - Pandeng Zhou
- School of Chemistry and Environmental Engineering, Hunan City University, Yiyang 413000, China.
| | - Xing Wu
- State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640, China.
| | - Jianliang Sun
- State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou 510640, China.
| | - Shicheng Chen
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, MI 48824, USA.
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Bautista LF, Morales G, Sanz R. Biodegradation of polycyclic aromatic hydrocarbons (PAHs) by laccase from Trametes versicolor covalently immobilized on amino-functionalized SBA-15. CHEMOSPHERE 2015; 136:273-280. [PMID: 26048814 DOI: 10.1016/j.chemosphere.2015.05.071] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2015] [Revised: 05/05/2015] [Accepted: 05/19/2015] [Indexed: 06/04/2023]
Abstract
A covalent immobilization method based on glutaraldehyde and amino-functionalized SBA-15 supports has been successfully applied to covalently and stably immobilize laccase from Trametes versicolor. The resultant biocatalysts displayed high incorporation yields of enzyme and led to excellent biodegradation rates of selected HPAs models, i.e. naphthalene, phenanthrene and anthracene, in water. The nature of the hydrocarbon chain accompanying the amino group has been shown as determinant for the immobilization as well as for the activity and reusability of the materials. Thus, alkyl moieties displayed higher enzyme loadings than phenyl moieties, being more adequate the larger n-butyl tethering residue likely due to its higher mobility. Using the aminobutyl-based laccase-SBA-15, 82%, 73%, and 55% conversion of naphthalene, phenanthrene and anthracene, respectively, were achieved after 48 h, very close to the values obtained with free laccase under the same reaction conditions. On the other hand, aminopropyl-based laccase-SBA-15 biocatalysts displayed the best reusability properties, retaining higher activity after four repeated uses than the corresponding aminobutyl-based materials.
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Affiliation(s)
- Luis Fernando Bautista
- Department of Chemical and Energy Technology, Chemical and Environmental Technology, Mechanical Technology and Analytical Chemistry, ESCET, Universidad Rey Juan Carlos, C/Tulipán s/n, 28933 Móstoles, Madrid, Spain.
| | - Gabriel Morales
- Department of Chemical and Energy Technology, Chemical and Environmental Technology, Mechanical Technology and Analytical Chemistry, ESCET, Universidad Rey Juan Carlos, C/Tulipán s/n, 28933 Móstoles, Madrid, Spain
| | - Raquel Sanz
- Department of Chemical and Energy Technology, Chemical and Environmental Technology, Mechanical Technology and Analytical Chemistry, ESCET, Universidad Rey Juan Carlos, C/Tulipán s/n, 28933 Móstoles, Madrid, Spain
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36
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Continuous Decolorization of Acid Blue 62 Solution in an Enzyme Membrane Reactor. Appl Biochem Biotechnol 2015; 177:237-52. [PMID: 26245258 PMCID: PMC4549384 DOI: 10.1007/s12010-015-1741-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2015] [Accepted: 06/30/2015] [Indexed: 11/15/2022]
Abstract
This paper focuses on using an enzyme membrane reactor (EMR) for the effective continuous decolorization of Acid Blue 62 (AB62). The following factors were considered for the effective use of Cerrena unicolor laccase immobilized in the EMR volume: the enzyme was stable in six successive runs in a batch reactor; no aeration was necessary; AB62 and the oxidized products were sorbed onto the membrane but were not rejected; and the enzyme was stable in the EMR system. It is obvious that any continuous process must be predictable, and thus, the objective was to verify the process model experimentally. For this reason, a proper isoenzyme kinetic equation was selected and the parameters were evaluated. The obtained kinetic parameters were used to plan processes and to verify their applicability to long-term AB62 decolorization, and a very good agreement between the calculated and the measured data was obtained. In the main designed continuous decolorization process, the conversion reached 98 % and was stable for 4 days. The membrane reactor with C. unicolor laccase appears to be very promising for AB62 decolorization.
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Yang J, Yang X, Lin Y, Ng TB, Lin J, Ye X. Laccase-catalyzed decolorization of malachite green: performance optimization and degradation mechanism. PLoS One 2015; 10:e0127714. [PMID: 26020270 PMCID: PMC4447439 DOI: 10.1371/journal.pone.0127714] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2014] [Accepted: 04/17/2015] [Indexed: 11/19/2022] Open
Abstract
Malachite green (MG) was decolorized by laccase (LacA) of white-rot fungus Cerrena sp. with strong decolorizing ability. Decolorization conditions were optimized with response surface methodology. A highly significant quadratic model was developed to investigate MG decolorization with LacA, and the maximum MG decolorization ratio of 91.6% was predicted under the conditions of 2.8 U mL(-1) LacA, 109.9 mg L(-1) MG and decolorization for 172.4 min. Kinetic studies revealed the Km and kcat values of LacA toward MG were 781.9 mM and 9.5 s(-1), respectively. UV-visible spectra confirmed degradation of MG, and the degradation mechanism was explored with liquid chromatography-mass spectrometry (LC-MS) analysis. Based on the LC-MS spectra of degradation products, LacA catalyzed MG degradation via two simultaneous pathways. In addition, the phytotoxicity of MG, in terms of inhibition on seed germination and seedling root elongation of Nicotiana tabacum and Lactuca sativa, was reduced after laccase treatment. These results suggest that laccase of Cerrena was effective in decolorizing MG and promising in bioremediation of wastewater in food and aquaculture industries.
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Affiliation(s)
- Jie Yang
- College of Biological Sciences and Technology, Fuzhou University, Fuzhou, Fujian, China
- Fujian Key Laboratory of Marine Enzyme Engineering, Fuzhou, Fujian, China
| | - Xiaodan Yang
- College of Biological Sciences and Technology, Fuzhou University, Fuzhou, Fujian, China
- Fujian Key Laboratory of Marine Enzyme Engineering, Fuzhou, Fujian, China
| | - Yonghui Lin
- Technical Center, Fujian Entry-Exit Inspection and Quarantine Bureau, Fuzhou, Fujian, China
| | - Tzi Bun Ng
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Juan Lin
- College of Biological Sciences and Technology, Fuzhou University, Fuzhou, Fujian, China
- Fujian Key Laboratory of Marine Enzyme Engineering, Fuzhou, Fujian, China
| | - Xiuyun Ye
- College of Biological Sciences and Technology, Fuzhou University, Fuzhou, Fujian, China
- Fujian Key Laboratory of Marine Enzyme Engineering, Fuzhou, Fujian, China
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38
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Chhabra M, Mishra S, Sreekrishnan TR. Immobilized laccase mediated dye decolorization and transformation pathway of azo dye acid red 27. JOURNAL OF ENVIRONMENTAL HEALTH SCIENCE & ENGINEERING 2015; 13:38. [PMID: 25932329 PMCID: PMC4415393 DOI: 10.1186/s40201-015-0192-0] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/26/2013] [Accepted: 04/15/2015] [Indexed: 06/04/2023]
Abstract
BACKGROUND Laccases have good potential as bioremediating agents and can be used continuously in the immobilized form like many other enzymes. METHODS In the present study, laccase from Cyathus bulleri was immobilized by entrapment in Poly Vinyl Alcohol (PVA) beads cross-linked with either nitrate or boric acid. Immobilized laccase was used for dye decolorization in both batch and continuous mode employing a packed bed column. The products of degradation of dye Acid Red 27 were identified by LC MS/MS analysis. RESULTS The method led to very effective (90%) laccase immobilization and also imparted significant stability to the enzyme (more than 70% after 5 months of storage at 4°C). In batch decolorization, 90-95% decolorization was achieved of the simulated dye effluent for up to 10-20 cycles. Continuous decolorization in a packed bed bioreactor led to nearly 90% decolorization for up to 5 days. The immobilized laccase was also effective in decolorization and degradation of Acid Red 27 in the presence of a mediator. Four products of degradation were identified by LC-MS/MS analysis. CONCLUSIONS The immobilized laccase in PVA-nitrate was concluded to be an effective agent in treatment of textile dye effluents.
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Affiliation(s)
- Meenu Chhabra
- />Department of Biology, Indian Institute of Technology-Jodhpur, Jodhpur, 342011 Rajasthan India
| | - Saroj Mishra
- />Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology Delhi, Hauz-Khas, New-Delhi, 110016 India
| | - Trichur Ramaswamy Sreekrishnan
- />Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology Delhi, Hauz-Khas, New-Delhi, 110016 India
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39
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Combination of chemical and enzymatic treatment for efficient decolorization/degradation of textile effluent: High operational stability of the continuous process. Biochem Eng J 2015. [DOI: 10.1016/j.bej.2014.09.007] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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40
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de Cazes M, Abejón R, Belleville MP, Sanchez-Marcano J. Membrane bioprocesses for pharmaceutical micropollutant removal from waters. MEMBRANES 2014; 4:692-729. [PMID: 25295629 PMCID: PMC4289862 DOI: 10.3390/membranes4040692] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/11/2014] [Revised: 09/16/2014] [Accepted: 09/17/2014] [Indexed: 01/02/2023]
Abstract
The purpose of this review work is to give an overview of the research reported on bioprocesses for the treatment of domestic or industrial wastewaters (WW) containing pharmaceuticals. Conventional WW treatment technologies are not efficient enough to completely remove all pharmaceuticals from water. Indeed, these compounds are becoming an actual public health problem, because they are more and more present in underground and even in potable waters. Different types of bioprocesses are described in this work: from classical activated sludge systems, which allow the depletion of pharmaceuticals by bio-degradation and adsorption, to enzymatic reactions, which are more focused on the treatment of WW containing a relatively high content of pharmaceuticals and less organic carbon pollution than classical WW. Different aspects concerning the advantages of membrane bioreactors for pharmaceuticals removal are discussed, as well as the more recent studies on enzymatic membrane reactors to the depletion of these recalcitrant compounds.
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Affiliation(s)
- Matthias de Cazes
- Institut Européen des Membranes (IEM), ENSCM, UM2, CNRS, Université de Montpellier 2, CC 047, Place Eugène Bataillon 34095, France.
| | - Ricardo Abejón
- Institut Européen des Membranes (IEM), ENSCM, UM2, CNRS, Université de Montpellier 2, CC 047, Place Eugène Bataillon 34095, France.
| | - Marie-Pierre Belleville
- Institut Européen des Membranes (IEM), ENSCM, UM2, CNRS, Université de Montpellier 2, CC 047, Place Eugène Bataillon 34095, France.
| | - José Sanchez-Marcano
- Institut Européen des Membranes (IEM), ENSCM, UM2, CNRS, Université de Montpellier 2, CC 047, Place Eugène Bataillon 34095, France.
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41
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Structural insights into 2,2'-azino-Bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS)-mediated degradation of reactive blue 21 by engineered Cyathus bulleri Laccase and characterization of degradation products. Appl Environ Microbiol 2014; 80:7484-95. [PMID: 25261507 DOI: 10.1128/aem.02665-14] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Advanced oxidation processes are currently used for the treatment of different reactive dyes which involve use of toxic catalysts. Peroxidases are reported to be effective on such dyes and require hydrogen peroxide and/or metal ions. Cyathus bulleri laccase, expressed in Pichia pastoris, catalyzes efficient degradation (78 to 85%) of reactive azo dyes (reactive black 5, reactive orange 16, and reactive red 198) in the presence of synthetic mediator ABTS [2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)]. This laccase was engineered to degrade effectively reactive blue 21 (RB21), a phthalocyanine dye reported to be decolorized only by peroxidases. The 816-bp segment (toward the C terminus) of the lcc gene was subjected to random mutagenesis and enzyme variants (Lcc35, Lcc61, and Lcc62) were selected based on increased ABTS oxidizing ability. Around 78 to 95% decolorization of RB21 was observed with the ABTS-supplemented Lcc variants in 30 min. Analysis of the degradation products by mass spectrometry indicated the formation of several low-molecular-weight compounds. Mapping the mutations on the modeled structure implicated residues both near and far from the T1 Cu site that affected the catalytic efficiency of the mutant enzymes on ABTS and, in turn, the rate of oxidation of RB21. Several inactive clones were also mapped. The importance of geometry as well as electronic changes on the reactivity of laccases was indicated.
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42
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Nguyen LN, Hai FI, Price WE, Leusch FDL, Roddick F, Ngo HH, Guo W, Magram SF, Nghiem LD. The effects of mediator and granular activated carbon addition on degradation of trace organic contaminants by an enzymatic membrane reactor. BIORESOURCE TECHNOLOGY 2014; 167:169-177. [PMID: 24980029 DOI: 10.1016/j.biortech.2014.05.125] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2014] [Revised: 05/30/2014] [Accepted: 05/31/2014] [Indexed: 06/03/2023]
Abstract
The removal of four recalcitrant trace organic contaminants (TrOCs), namely carbamazepine, diclofenac, sulfamethoxazole and atrazine by laccase in an enzymatic membrane reactor (EMR) was studied. Laccases are not effective for degrading non-phenolic compounds; nevertheless, 22-55% removal of these four TrOCs was achieved by the laccase EMR. Addition of the redox-mediator syringaldehyde (SA) to the EMR resulted in a notable dose-dependent improvement (15-45%) of TrOC removal affected by inherent TrOC properties and loading rates. However, SA addition resulted in a concomitant increase in the toxicity of the treated effluent. A further 14-25% improvement in aqueous phase removal of the TrOCs was consistently observed following a one-off dosing of 3g/L granular activated carbon (GAC). Mass balance analysis reveals that this improvement was not due solely to adsorption but also enhanced biodegradation. GAC addition also reduced membrane fouling and the SA-induced toxicity of the effluent.
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Affiliation(s)
- Luong N Nguyen
- Strategic Water Infrastructure Lab, School of Civil, Mining and Environmental Engineering, University of Wollongong, Wollongong, NSW 2522, Australia
| | - Faisal I Hai
- Strategic Water Infrastructure Lab, School of Civil, Mining and Environmental Engineering, University of Wollongong, Wollongong, NSW 2522, Australia.
| | - William E Price
- Strategic Water Infrastructure Lab, School of Chemistry, University of Wollongong, Wollongong, NSW 2522, Australia
| | | | - Felicity Roddick
- School of Civil, Environmental and Chemical Engineering, RMIT University, Melbourne, Victoria 3001, Australia
| | - Hao H Ngo
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, Sydney, Broadway, NSW 2007, Australia
| | - Wenshan Guo
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, Sydney, Broadway, NSW 2007, Australia
| | - Saleh F Magram
- Department of Civil Engineering, King Abdul Aziz University, Jeddah 21589, Saudi Arabia
| | - Long D Nghiem
- Strategic Water Infrastructure Lab, School of Civil, Mining and Environmental Engineering, University of Wollongong, Wollongong, NSW 2522, Australia
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43
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Mazzonna M, Bietti M, DiLabio GA, Lanzalunga O, Salamone M. Importance of π-Stacking Interactions in the Hydrogen Atom Transfer Reactions from Activated Phenols to Short-Lived N-Oxyl Radicals. J Org Chem 2014; 79:5209-18. [DOI: 10.1021/jo500789v] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
- Marco Mazzonna
- Dipartimento
di Chimica and Istituto CNR di Metodologie
Chimiche (IMC−CNR), Sezione Meccanismi di Reazione, c/o Dipartimento
di Chimica, Sapienza Università di Roma, P.le A. Moro, 5, I-00185 Rome, Italy
| | - Massimo Bietti
- Dipartimento
di Scienze e Tecnologie Chimiche, Università “Tor Vergata”, Via della Ricerca Scientifica, 1, I-00133 Rome, Italy
| | - Gino A. DiLabio
- National
Institute for Nanotechnology, National Research Council of Canada, 11421
Saskatchewan Drive, Edmonton, Alberta, Canada T6G 2M9
- Department
of Chemistry, University of British Columbia, Okanagan, 3333 University
Way, Kelowna, British Columbia, Canada V1V 1V7
| | - Osvaldo Lanzalunga
- Dipartimento
di Chimica and Istituto CNR di Metodologie
Chimiche (IMC−CNR), Sezione Meccanismi di Reazione, c/o Dipartimento
di Chimica, Sapienza Università di Roma, P.le A. Moro, 5, I-00185 Rome, Italy
| | - Michela Salamone
- Dipartimento
di Scienze e Tecnologie Chimiche, Università “Tor Vergata”, Via della Ricerca Scientifica, 1, I-00133 Rome, Italy
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44
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Comparing the catalytic efficiency of ring substituted 1-hydroxybenzotriazoles as laccase mediators. Tetrahedron 2014. [DOI: 10.1016/j.tet.2014.02.068] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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45
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On the use of a high-redox potential laccase as an alternative for the transformation of non-steroidal anti-inflammatory drugs (NSAIDs). ACTA ACUST UNITED AC 2013. [DOI: 10.1016/j.molcatb.2013.08.021] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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46
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Wong KS, Cheung MK, Au CH, Kwan HS. A novel Lentinula edodes laccase and its comparative enzymology suggest guaiacol-based laccase engineering for bioremediation. PLoS One 2013; 8:e66426. [PMID: 23799101 PMCID: PMC3683064 DOI: 10.1371/journal.pone.0066426] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2012] [Accepted: 05/09/2013] [Indexed: 11/18/2022] Open
Abstract
Laccases are versatile biocatalysts for the bioremediation of various xenobiotics, including dyes and polyaromatic hydrocarbons. However, current sources of new enzymes, simple heterologous expression hosts and enzymatic information (such as the appropriateness of common screening substrates on laccase engineering) remain scarce to support efficient engineering of laccase for better "green" applications. To address the issue, this study began with cloning the laccase family of Lentinula edodes. Three laccases perfectio sensu stricto (Lcc4A, Lcc5, and Lcc7) were then expressed from Pichia pastoris, characterized and compared with the previously reported Lcc1A and Lcc1B in terms of kinetics, stability, and degradation of dyes and polyaromatic hydrocarbons. Lcc7 represented a novel laccase, and it exhibited both the highest catalytic efficiency (assayed with 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) [ABTS]) and thermostability. However, its performance on "green" applications surprisingly did not match the activity on the common screening substrates, namely, ABTS and 2,6-dimethoxyphenol. On the other hand, correlation analyses revealed that guaiacol is much better associated with the decolorization of multiple structurally different dyes than are the two common screening substrates. Comparison of the oxidation chemistry of guaiacol and phenolic dyes, such as azo dyes, further showed that they both involve generation of phenoxyl radicals in laccase-catalyzed oxidation. In summary, this study concluded a robust expression platform of L. edodes laccases, novel laccases, and an indicative screening substrate, guaiacol, which are all essential fundamentals for appropriately driving the engineering of laccases towards more efficient "green" applications.
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Affiliation(s)
- Kin-Sing Wong
- School of Life Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Man-Kit Cheung
- School of Life Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Chun-Hang Au
- School of Life Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Hoi-Shan Kwan
- School of Life Sciences, The Chinese University of Hong Kong, Shatin, Hong Kong
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Sathishkumar P, Palvannan T, Murugesan K, Kamala-Kannan S. Detoxification of malachite green by Pleurotus florida laccase produced under solid-state fermentation using agricultural residues. ENVIRONMENTAL TECHNOLOGY 2013; 34:139-147. [PMID: 23530324 DOI: 10.1080/09593330.2012.689359] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Laccase was produced from Pleurotus florida under solid-state fermentation, and the production was optimized by response surface methodology. The predicted maximum laccase production of 8.81 U g(-1) was obtained by the optimum concentration of malt extract, banana peel, wheat bran and CuSO4, which was found to be 0.69 g, 10.61 g, 10.68 g and 77.15 ppm, respectively. The validation results suggested that the laccase production was 7.96 U g(-1) in the optimized medium, which was close to the predicted value. Decolorization efficiency of P. florida laccase was evaluated against malachite green (MG). Rapid decolorization of MG dye was observed, and a dark-coloured precipitate was formed in the reaction mixture. HPLC analysis indicated that the laccase enzyme degraded MG by the demethylation process. The toxicity of MG was reduced to 67% after the treatment with laccase, which was confirmed by a phytotoxicity study.
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Affiliation(s)
- Palanivel Sathishkumar
- Laboratory of Bioprocess and Engineering, Department of Biochemistry, Periyar University, Salem, Tamil Nadu 636 011, India.
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Garg N, Bieler N, Kenzom T, Chhabra M, Ansorge-Schumacher M, Mishra S. Cloning, sequence analysis, expression of Cyathus bulleri laccase in Pichia pastoris and characterization of recombinant laccase. BMC Biotechnol 2012; 12:75. [PMID: 23092193 PMCID: PMC3558336 DOI: 10.1186/1472-6750-12-75] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2012] [Accepted: 10/08/2012] [Indexed: 12/03/2022] Open
Abstract
Background Laccases are blue multi-copper oxidases and catalyze the oxidation of phenolic and non-phenolic compounds. There is considerable interest in using these enzymes for dye degradation as well as for synthesis of aromatic compounds. Laccases are produced at relatively low levels and, sometimes, as isozymes in the native fungi. The investigation of properties of individual enzymes therefore becomes difficult. The goal of this study was to over-produce a previously reported laccase from Cyathus bulleri using the well-established expression system of Pichia pastoris and examine and compare the properties of the recombinant enzyme with that of the native laccase. Results In this study, complete cDNA encoding laccase (Lac) from white rot fungus Cyathus bulleri was amplified by RACE-PCR, cloned and expressed in the culture supernatant of Pichia pastoris under the control of the alcohol oxidase (AOX)1 promoter. The coding region consisted of 1,542 bp and encodes a protein of 513 amino acids with a signal peptide of 16 amino acids. The deduced amino acid sequence of the matured protein displayed high homology with laccases from Trametes versicolor and Coprinus cinereus. The sequence analysis indicated the presence of Glu 460 and Ser 113 and LEL tripeptide at the position known to influence redox potential of laccases placing this enzyme as a high redox enzyme. Addition of copper sulfate to the production medium enhanced the level of laccase by about 12-fold to a final activity of 7200 U L-1. The recombinant laccase (rLac) was purified by ~4-fold to a specific activity of ~85 U mg-1 protein. A detailed study of thermostability, chloride and solvent tolerance of the rLac indicated improvement in the first two properties when compared to the native laccase (nLac). Altered glycosylation pattern, identified by peptide mass finger printing, was proposed to contribute to altered properties of the rLac. Conclusion Laccase of C. bulleri was successfully produced extra-cellularly to a high level of 7200 U L-1 in P. pastoris under the control of the AOX1 promoter and purified by a simple three-step procedure to homogeneity. The kinetic parameters against ABTS, Guaiacol and Pyrogallol were similar with the nLac and the rLac. Tryptic finger print analysis of the nLac and the rLac indicated altered glycosylation patterns. Increased thermo-stability and salt tolerance of the rLac was attributed to this changed pattern of glycosylation.
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Affiliation(s)
- Neha Garg
- Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology Delhi, Hauz-Khas, New Delhi 110016, India
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Li Y, Cao X, Qian X, Chen Y, Liu S. Immobilization of laccase in N-doped carbon hollow spheres/chitosan composite film for electrochemical detection of kraft lignin. J Electroanal Chem (Lausanne) 2012. [DOI: 10.1016/j.jelechem.2012.09.013] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Zhang X, Zhang S, Pan B, Hua M, Zhao X. Simple fabrication of polymer-based Trametes versicolor laccase for decolorization of malachite green. BIORESOURCE TECHNOLOGY 2012; 115:16-20. [PMID: 22169216 DOI: 10.1016/j.biortech.2011.11.063] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2011] [Revised: 11/16/2011] [Accepted: 11/17/2011] [Indexed: 05/31/2023]
Abstract
A highly efficient and stable biocatalyst (denoted D201_Lac) was fabricated by encapsulating Trametes versicolor laccase within a macroporous and strongly basic exchange resin D201 through a simple adsorption process. Transmission electron micrographs and Fourier transform infrared spectra of the resultant D201_Lac proved that nanosized laccase clusters were embedded into the inner nano-pores/channels of D201. As compared to the free laccase, D201_Lac showed enhanced resistance in the pH range of 3-7 or at temperature of 30-60°C. Besides, negligible laccase was leached out from the host polymer D201 in solution of pH 3-7 and NaCl concentration up to 0.5M, which might be attributed to the electrostatic attraction and the possible twining between long-chain laccase and the cross-linking host resin. Continuous seven-cycle batch decoloration of malachite green demonstrates that decoloration efficiency of D201_Lac kept constant for more than 320-h operation.
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Affiliation(s)
- Xiaolin Zhang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210093, PR China
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