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Ali M, Bhardwaj P, Ishqi HM, Shahid M, Islam A. Laccase Engineering: Redox Potential Is Not the Only Activity-Determining Feature in the Metalloproteins. Molecules 2023; 28:6209. [PMID: 37687038 PMCID: PMC10488915 DOI: 10.3390/molecules28176209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2023] [Revised: 08/02/2023] [Accepted: 08/08/2023] [Indexed: 09/10/2023] Open
Abstract
Laccase, one of the metalloproteins, belongs to the multicopper oxidase family. It oxidizes a wide range of substrates and generates water as a sole by-product. The engineering of laccase is important to broaden their industrial and environmental applications. The general assumption is that the low redox potential of laccases is the principal obstacle, as evidenced by their low activity towards certain substrates. Therefore, the primary goal of engineering laccases is to improve their oxidation capability, thereby increasing their redox potential. Even though some of the determinants of laccase are known, it is still not entirely clear how to enhance its redox potential. However, the laccase active site has additional characteristics that regulate the enzymes' activity and specificity. These include the electrostatic and hydrophobic environment of the substrate binding pocket, the steric effect at the substrate binding site, and the orientation of the binding substrate with respect to the T1 site of the laccase. In this review, these features of the substrate binding site will be discussed to highlight their importance as a target for future laccase engineering.
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Affiliation(s)
- Misha Ali
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, New Delhi 110025, India; (M.A.); (P.B.)
| | - Priyanka Bhardwaj
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, New Delhi 110025, India; (M.A.); (P.B.)
| | - Hassan Mubarak Ishqi
- Department of Surgery and Sylvester Comprehensive Cancer Center, Miller School of Medicine, Miami, FL 33136, USA;
| | - Mohammad Shahid
- Department of Basic Medical Sciences, College of Medicine, Prince Sattam Bin Abdulaziz University, Al-Kharj 16273, Saudi Arabia
| | - Asimul Islam
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, New Delhi 110025, India; (M.A.); (P.B.)
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2
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Sutaoney P, Pandya S, Gajarlwar D, Joshi V, Ghosh P. Feasibility and potential of laccase-based enzyme in wastewater treatment through sustainable approach: A review. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:86499-86527. [PMID: 35771325 DOI: 10.1007/s11356-022-21565-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Accepted: 06/14/2022] [Indexed: 06/15/2023]
Abstract
The worldwide increase in metropolitan cities and rise in industrialization have resulted in the assimilation of hazardous pollutants into the ecosystems. Different physical, chemical and biological techniques have been employed to remove these toxins from water bodies. Several bioprocess applications using microbes and their enzymes are utilized to achieve the goal. Biocatalysts, such as laccases, are employed explicitly to deplete a variety of organic pollutants. However, the degradation of contaminants using biocatalysts has many disadvantages concerning the stability and activity of the enzyme. Hence, they are immobilized on different supports to improve the enzyme kinetics and recyclability. Furthermore, standard wastewater treatment methods are not effective in eliminating all the contaminants. As a result, membrane separation technologies have emerged to overcome the limitations of traditional wastewater treatment methods. Moreover, enzymes immobilized onto these membranes have generated new avenues in wastewater purification technology. This review provides the latest information on laccases from diverse sources, their molecular framework and their mode of action. This report also gives information about various immobilization techniques and the application of membrane bioreactors to eliminate and biotransform hazardous contaminants. In a nutshell, laccases appear to be the most promising biocatalysts for green and cost-efficient wastewater treatment technologies.
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Affiliation(s)
- Priya Sutaoney
- Center for Basic Sciences, Pt. Ravishankar Shukla University, Raipur, Chhattisgarh, India
| | - Srishti Pandya
- Center for Basic Sciences, Pt. Ravishankar Shukla University, Raipur, Chhattisgarh, India
| | - Devashri Gajarlwar
- Center for Basic Sciences, Pt. Ravishankar Shukla University, Raipur, Chhattisgarh, India
| | - Veenu Joshi
- Center for Basic Sciences, Pt. Ravishankar Shukla University, Raipur, Chhattisgarh, India
| | - Prabir Ghosh
- Department of Chemical Engineering, NIT Raipur, Raipur, Chhattisgarh, India.
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Review of advances in the development of laccases for the valorization of lignin to enable the production of lignocellulosic biofuels and bioproducts. Biotechnol Adv 2021; 54:107809. [PMID: 34333091 DOI: 10.1016/j.biotechadv.2021.107809] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Revised: 07/23/2021] [Accepted: 07/24/2021] [Indexed: 12/30/2022]
Abstract
Development and deployment of commercial biorefineries based on conversion of lignocellulosic biomass into biofuels and bioproducts faces many challenges that must be addressed before they are commercially viable. One of the biggest challenges faced is the efficient and scalable valorization of lignin, one of the three major components of the plant cell wall. Lignin is the most abundant aromatic biopolymer on earth, and its presence hinders the extraction of cellulose and hemicellulose that is essential to biochemical conversion of lignocellulose to fuels and chemicals. There has been a significant amount of work over the past 20 years that has sought to develop innovative processes designed to extract and recycle lignin into valuable compounds and help reduce the overall costs of the biorefinery process. Due to the complex matrix of lignin, which is essential for plant survival, the development of a reliable and efficient lignin conversion technology has been difficult to achieve. One approach that has received significant interest relies on the use of enzymes, notably laccases, a class of multi‑copper green oxidative enzymes that catalyze bond breaking in lignin to produce smaller oligomers. In this review, we first assess the different innovations of lignin valorization using laccases within the context of a biorefinery process, and then assess the latest economical advances that these innovations offered. Finally, we review laccase characterization and optimization, as well as the prospects and bottlenecks of this class of enzymes within the industrial and biorefining sectors.
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4
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Dai S, Yao Q, Yu G, Liu S, Yun J, Xiao X, Deng Z, Li H. Biochemical Characterization of a Novel Bacterial Laccase and Improvement of Its Efficiency by Directed Evolution on Dye Degradation. Front Microbiol 2021; 12:633004. [PMID: 34054745 PMCID: PMC8149590 DOI: 10.3389/fmicb.2021.633004] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Accepted: 04/07/2021] [Indexed: 11/30/2022] Open
Abstract
Laccase is a copper-containing polyphenol oxidase with a wide range of substrates, possessing a good application prospect in wastewater treatment and dye degradation. The purpose of this research is to study the degradation of various industrial dyes by recombinant laccase rlac1338 and the mutant enzyme lac2-9 with the highest enzyme activity after modification by error-prone PCR. Four enzyme activities improved mutant enzymes were obtained through preliminary screening and rescreening, of which lac2-9 has the highest enzyme activity. There are four mutation sites, including V281A, V281A, P309L, S318G, and D232V. The results showed that the expression of the optimized mutant enzyme also increased by 22 ± 2% compared to the unoptimized enzyme and the optimal reaction temperature of the mutant enzyme lac2-9 was 5°C higher than that of the rlac1338, and the optimal pH increased by 0.5 units. The thermal stability and pH stability of mutant enzyme lac2-9 were also improved. With ABTS as the substrate, the kcat/Km of rlac1338 and mutant strain lac2-9 are the largest than other substrates, 0.1638 and 0.618 s–1M–1, respectively, indicating that ABTS is the most suitable substrate for the recombinant enzyme and mutant enzyme. In addition, the Km of the mutant strain lac2-9 (76 μM) was significantly lower, but the kcat/Km (0.618 s–1M–1) was significantly higher, and the specific enzyme activity (79.8 U/mg) increased by 3.5 times compared with the recombinant laccase (22.8 U/mg). The dye degradation results showed that the use of rlac1338 and lac2-9 alone had no degradation effect on the industrial dyes [indigo, amaranth, bromophenol blue, acid violet 7, Congo red, coomassie brilliant blue (G250)], however, adding small molecular mediators Ca2+ and ABTS at the same time can significantly improve the degradation ability. Compared to the rlac1338, the degradation rates with the simultaneous addition of Ca2+ and ABTS of mutant enzyme lac2-9 for acid violet 7, bromophenol blue and coomassie brilliant blue significantly improved by 8.3; 3.4 and 3.4 times. Therefore, the results indicated that the error-prone PCR was a feasible method to improve the degradation activity of laccase for environmental pollutants, which provided a basis for the application of laccase on dye degradation and other environmental pollutants.
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Affiliation(s)
- Shuang Dai
- Guangdong Key Laboratory of Pharmaceutical Bioactive Substances, College of Life Science and Biopharmaceuticals, Guangdong Pharmaceutical University, Guangzhou, China
| | - Qian Yao
- Guangdong Key Laboratory of Pharmaceutical Bioactive Substances, College of Life Science and Biopharmaceuticals, Guangdong Pharmaceutical University, Guangzhou, China
| | - Gen Yu
- Guangdong Key Laboratory of Pharmaceutical Bioactive Substances, College of Life Science and Biopharmaceuticals, Guangdong Pharmaceutical University, Guangzhou, China
| | - Shan Liu
- Guangzhou Base Clean Cosmetics Manufacturer Co., Ltd., Guangzhou, China
| | - Jeonyun Yun
- Guangzhou Base Clean Cosmetics Manufacturer Co., Ltd., Guangzhou, China
| | - Xiong Xiao
- Guangzhou Base Clean Cosmetics Manufacturer Co., Ltd., Guangzhou, China
| | - Zujun Deng
- Guangdong Key Laboratory of Pharmaceutical Bioactive Substances, College of Life Science and Biopharmaceuticals, Guangdong Pharmaceutical University, Guangzhou, China
| | - He Li
- Guangdong Key Laboratory of Pharmaceutical Bioactive Substances, College of Life Science and Biopharmaceuticals, Guangdong Pharmaceutical University, Guangzhou, China
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Miranda-Blancas R, Avelar M, Rodriguez-Arteaga A, Sinicropi A, Rudiño-Piñera E. The β-hairpin from the Thermus thermophilus HB27 laccase works as a pH-dependent switch to regulate laccase activity. J Struct Biol 2021; 213:107740. [PMID: 33962016 DOI: 10.1016/j.jsb.2021.107740] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 04/30/2021] [Accepted: 04/30/2021] [Indexed: 11/29/2022]
Abstract
The multi-copper oxidase from the hyper-thermophilic bacteria Thermus thermophilus (Tth-MCO), has been previously characterized and described as an example of a laccase with low catalytic properties, especially when it is compared with the activity of fungal laccases, but it is active at high temperatures. Structurally, Tth-MCO has a unique feature: a β-hairpin near the T1Cu site, which is not present in any other laccases deposited at the PDB. This β-hairpin has an expected crystallographic behavior in solvent-exposed areas of a crystallized protein: lack of electron density, high B-values and several crystalline contacts with neighboring crystallographic copies; however, its dynamical behavior in solution and its biological implications have not been described. Here, we describe four new Tth-MCO crystallographic structures, and the β-hairpin behavior has been analyzed by molecular dynamics simulations, considering the effect of pH and temperature. The β-hairpin new crystallographic conformations described here, together with their dynamics, were used to understand the pH-restrained laccase activity of Tth-MCO against substrates as syringaldazine. Remarkably, there are insertions in laccases from Thermus and Meiothermus genus, sharing the same position and a methionine-rich composition of the Tth-MCO β-hairpin. This unique high methionine content of the Tth-MCO β-hairpin is responsible to coordinate, Ag+1 and Hg+1 in oxidative conditions, but Cu+1 and Cu+2 are not coordinated in crystallographic experiments, regardless of the redox conditions; however, Ag+1 addition does not affect Tth-MCO laccase activity against syringaldazine. Here, we propose that the pH-dependent β-hairpin dynamical behavior could explain, at least in part, the inefficient laccase activity displayed by Tth-MCO in acidic pH values.
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Affiliation(s)
- R Miranda-Blancas
- Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnología, Universidad Nacional Autónoma de México, 2001 Universidad Av., Cuernavaca, Morelos 62210, Mexico; Instituto de Investigación en Dinámica Celular, Universidad Autónoma del Estado de Morelos, 1001 Universidad Av., Cuernavaca, Morelos 62209, Mexico
| | - M Avelar
- Department of Biotechnology, Chemistry and Pharmacy, University of Siena, 53100 Siena, Italy
| | - A Rodriguez-Arteaga
- Departamento de Ingeniería Celular y Biocatálisis, Instituto de Biotecnología, Universidad Nacional Autónoma de México, 2001 Universidad Av., Cuernavaca, Morelos 62210, Mexico
| | - A Sinicropi
- Department of Biotechnology, Chemistry and Pharmacy, University of Siena, 53100 Siena, Italy; Institute of Chemistry of Organometallic Compounds (CNR-ICCOM), Via Madonna del Piano 10, 50019 Sesto Fiorentino, Italy; CSGI, Consorzio per lo Sviluppo dei Sistemi a Grande Interfase, 50019 Sesto Fiorentino, Italy
| | - E Rudiño-Piñera
- Departamento de Medicina Molecular y Bioprocesos, Instituto de Biotecnología, Universidad Nacional Autónoma de México, 2001 Universidad Av., Cuernavaca, Morelos 62210, Mexico.
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Madhavan A, Arun KB, Binod P, Sirohi R, Tarafdar A, Reshmy R, Kumar Awasthi M, Sindhu R. Design of novel enzyme biocatalysts for industrial bioprocess: Harnessing the power of protein engineering, high throughput screening and synthetic biology. BIORESOURCE TECHNOLOGY 2021; 325:124617. [PMID: 33450638 DOI: 10.1016/j.biortech.2020.124617] [Citation(s) in RCA: 47] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Revised: 12/19/2020] [Accepted: 12/22/2020] [Indexed: 05/13/2023]
Abstract
Biocatalysts have wider applications in various industries. Biocatalysts are generating bigger attention among researchers due to their unique catalytic properties like activity, specificity and stability. However the industrial use of many enzymes is hindered by low catalytic efficiency and stability during industrial processes. Properties of enzymes can be altered by protein engineering. Protein engineers are increasingly study the structure-function characteristics, engineering attributes, design of computational tools for enzyme engineering, and functional screening processes to improve the design and applications of enzymes. The potent and innovative techniques of enzyme engineering deliver outstanding opportunities for tailoring industrially important enzymes for the versatile production of biochemicals. An overview of the current trends in enzyme engineering is explored with important representative examples.
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Affiliation(s)
- Aravind Madhavan
- Rajiv Gandhi Centre for Biotechnology, Trivandrum 695 014, India
| | - K B Arun
- Rajiv Gandhi Centre for Biotechnology, Trivandrum 695 014, India
| | - Parameswaran Binod
- Microbial Processes and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology (CSIR-NIIST), Trivandrum 695 019, India
| | - Ranjna Sirohi
- The Center for Energy and Environmental Sustainability, Lucknow 226 010, Uttar Pradesh, India
| | - Ayon Tarafdar
- Division of Livestock Production and Management, ICAR - Indian Veterinary Research Institute, Izatnagar, Bareilly 243 122, Uttar Pradesh, India
| | - R Reshmy
- Post Graduate and Research Department of Chemistry, Bishop Moore College, Mavelikara 690 110, Kerala, India
| | - Mukesh Kumar Awasthi
- College of Natural Resources and Environment, North West A & F University, Yangling, Shaanxi 712 100, China
| | - Raveendran Sindhu
- Microbial Processes and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology (CSIR-NIIST), Trivandrum 695 019, India.
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7
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Sekan AS, Myronycheva OS, Karlsson O, Gryganskyi AP, Blume Y. Green potential of Pleurotus spp. in biotechnology. PeerJ 2019; 7:e6664. [PMID: 30967974 PMCID: PMC6446892 DOI: 10.7717/peerj.6664] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Accepted: 02/22/2019] [Indexed: 11/20/2022] Open
Abstract
BACKGROUND The genus Pleurotus is most exploitable xylotrophic fungi, with valuable biotechnological, medical, and nutritional properties. The relevant features of the representatives of this genus to provide attractive low-cost industrial tools have been reported in numerous studies to resolve the pressure of ecological issues. Additionally, a number of Pleurotus species are highly adaptive, do not require any special conditions for growth, and possess specific resistance to contaminating diseases and pests. The unique properties of Pleurotus species widely used in many environmental technologies, such as organic solid waste recycling, chemical pollutant degradation, and bioethanol production. METHODOLOGY The literature study encompasses peer-reviewed journals identified by systematic searches of electronic databases such as Google Scholar, NCBI, Springer, ResearchGate, ScienceDirect, and ISI Web of Knowledge. The search scheme was divided into several steps, as described below. RESULTS In this review, we describe studies examining the biotechnological feasibility of Pleurotus spp. to elucidate the importance of this genus for use in green technology. Here, we review areas of application of the genus Pleurotus as a prospective biotechnological tool. CONCLUSION The incomplete description of some fungal biochemical pathways emphasises the future research goals for this fungal culture.
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Affiliation(s)
- Alona S. Sekan
- Institute of Food Biotechnology and Genomics, National Academy of Science of Ukraine, Kyiv, Ukraine
| | - Olena S. Myronycheva
- Division of Wood Science and Engineering, Department of Engineering Sciences and Mathematics, Lulea University of Technology, Skelleftea, Sweden
| | - Olov Karlsson
- Division of Wood Science and Engineering, Department of Engineering Sciences and Mathematics, Lulea University of Technology, Skelleftea, Sweden
| | | | - Yaroslav Blume
- Institute of Food Biotechnology and Genomics, National Academy of Science of Ukraine, Kyiv, Ukraine
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Directed Evolution of a Homodimeric Laccase from Cerrena unicolor BBP6 by Random Mutagenesis and In Vivo Assembly. Int J Mol Sci 2018; 19:ijms19102989. [PMID: 30274366 PMCID: PMC6213006 DOI: 10.3390/ijms19102989] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2018] [Revised: 09/19/2018] [Accepted: 09/27/2018] [Indexed: 11/21/2022] Open
Abstract
Laccases have great potential for industrial applications due to their green catalytic properties and broad substrate specificities, and various studies have attempted to improve the catalytic performance of these enzymes. Here, to the best of our knowledge, we firstly report the directed evolution of a homodimeric laccase from Cerrena unicolor BBP6 fused with α-factor prepro-leader that was engineered through random mutagenesis followed by in vivo assembly in Saccharomyces cerevisiae. Three evolved fusion variants selected from ~3500 clones presented 31- to 37-fold increases in total laccase activity, with better thermostability and broader pH profiles. The evolved α-factor prepro-leader enhanced laccase expression levels by up to 2.4-fold. Protein model analysis of these variants reveals that the beneficial mutations have influences on protein pKa shift, subunit interaction, substrate entrance, and C-terminal function.
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9
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Du W, Sun C, Wang J, Wang B, Yao Z, Qu F, Xia J, Xie W, Sun J, Duan D. Isolation, identification of a laccase-producing fungal strain and enzymatic properties of the laccase. 3 Biotech 2018; 8:137. [PMID: 29479513 DOI: 10.1007/s13205-018-1149-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Accepted: 02/02/2018] [Indexed: 10/18/2022] Open
Abstract
A new type of thermostable laccase was isolated from Paraphoma sp. GZS18, and its partial enzymatic properties were determined. A strain GZS18 of laccase with high yield was screened from forest soil and identified as Paraphoma sp. GZS18 through morphological characteristics and ITS sequence analysis. The laccase of Paraphoma sp. GZS18 (Lac-P) was obtained through cation-anion exchange chromatography, gel filtration chromatography, and other purification processes. The testing result shows that Lac-P is a single protein of 75 kDa, and the 11 amino acid sequences in the N-terminal are AXaVSVASREMT (Xa was the non-standard protein). The optimum temperature and optimum pH of lac-P activity are substrate-independent. The temperature is in the range of 50-70 °C, and pH has high catalytic efficiency in the acidic range. Lac-P has good stability in the temperature and pH. The half time at 70-60 °C is 1.5 and 4 h, respectively. At pH 6-9 and room temperature, there is more than 80% activity 24 h later. Lac-P is tolerant of most metal ions and low concentrations of inhibitors but is inhibited by Hg2+, Fe2+ and NaN3. The laccase from Paraphoma sp. GZS18 at high temperature and pH 6-9, with strong stability, has better industrial application characteristics.
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Scheiblbrandner S, Breslmayr E, Csarman F, Paukner R, Führer J, Herzog PL, Shleev SV, Osipov EM, Tikhonova TV, Popov VO, Haltrich D, Ludwig R, Kittl R. Evolving stability and pH-dependent activity of the high redox potential Botrytis aclada laccase for enzymatic fuel cells. Sci Rep 2017; 7:13688. [PMID: 29057958 PMCID: PMC5651918 DOI: 10.1038/s41598-017-13734-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Accepted: 09/27/2017] [Indexed: 12/24/2022] Open
Abstract
Fungal high redox potential laccases are proposed as cathodic biocatalysts in implantable enzymatic fuel cells to generate high cell voltages. Their application is limited mainly through their acidic pH optimum and chloride inhibition. This work investigates evolutionary and engineering strategies to increase the pH optimum of a chloride-tolerant, high redox potential laccase from the ascomycete Botrytis aclada. The laccase was subjected to two rounds of directed evolution and the clones screened for increased stability and activity at pH 6.5. Beneficial mutation sites were investigated by semi-rational and combinatorial mutagenesis. Fourteen variants were characterised in detail to evaluate changes of the kinetic constants. Mutations increasing thermostability were distributed over the entire structure. Among them, T383I showed a 2.6-fold increased half-life by preventing the loss of the T2 copper through unfolding of a loop. Mutations affecting the pH-dependence cluster around the T1 copper and categorise in three types of altered pH profiles: pH-type I changes the monotonic decreasing pH profile into a bell-shaped profile, pH-type II describes increased specific activity below pH 6.5, and pH-type III increased specific activity above pH 6.5. Specific activities of the best variants were up to 5-fold higher (13 U mg−1) than BaL WT at pH 7.5.
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Affiliation(s)
- Stefan Scheiblbrandner
- Department of Food Sciences and Technology, VIBT - Vienna Institute of BioTechnology, BOKU - University of Natural Resources and Life Sciences, A-1190, Vienna, Austria
| | - Erik Breslmayr
- Department of Food Sciences and Technology, VIBT - Vienna Institute of BioTechnology, BOKU - University of Natural Resources and Life Sciences, A-1190, Vienna, Austria
| | - Florian Csarman
- Department of Food Sciences and Technology, VIBT - Vienna Institute of BioTechnology, BOKU - University of Natural Resources and Life Sciences, A-1190, Vienna, Austria
| | - Regina Paukner
- Department of Food Sciences and Technology, VIBT - Vienna Institute of BioTechnology, BOKU - University of Natural Resources and Life Sciences, A-1190, Vienna, Austria
| | - Johannes Führer
- Department of Food Sciences and Technology, VIBT - Vienna Institute of BioTechnology, BOKU - University of Natural Resources and Life Sciences, A-1190, Vienna, Austria
| | - Peter L Herzog
- Department of Food Sciences and Technology, VIBT - Vienna Institute of BioTechnology, BOKU - University of Natural Resources and Life Sciences, A-1190, Vienna, Austria
| | - Sergey V Shleev
- Biomedical Sciences, Health and Society, Malmö University, 20560, Malmö, Sweden
| | - Evgeny M Osipov
- Bach Institute of Biochemistry, Research Center of Biotechnology RAS, 119071, Moscow, Russian Federation
| | - Tamara V Tikhonova
- Bach Institute of Biochemistry, Research Center of Biotechnology RAS, 119071, Moscow, Russian Federation
| | - Vladimir O Popov
- Bach Institute of Biochemistry, Research Center of Biotechnology RAS, 119071, Moscow, Russian Federation
| | - Dietmar Haltrich
- Department of Food Sciences and Technology, VIBT - Vienna Institute of BioTechnology, BOKU - University of Natural Resources and Life Sciences, A-1190, Vienna, Austria
| | - Roland Ludwig
- Department of Food Sciences and Technology, VIBT - Vienna Institute of BioTechnology, BOKU - University of Natural Resources and Life Sciences, A-1190, Vienna, Austria
| | - Roman Kittl
- Department of Food Sciences and Technology, VIBT - Vienna Institute of BioTechnology, BOKU - University of Natural Resources and Life Sciences, A-1190, Vienna, Austria.
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11
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Variants of PpuLcc, a multi-dye decolorizing laccase from Pleurotus pulmonarius expressed in Pichia pastoris. Protein Expr Purif 2017; 137:34-42. [PMID: 28651974 DOI: 10.1016/j.pep.2017.06.014] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2016] [Revised: 05/08/2017] [Accepted: 06/21/2017] [Indexed: 01/03/2023]
Abstract
A laccase of the basidiomycete Pleurotus pulmonarius (PpuLcc) possessed strong decolorizing abilities towards artificial and natural dyes. The PpuLcc was purified from the culture supernatant via FPLC, and the corresponding gene cloned and expressed in Pichia pastoris GS115. To examine the impact of the C-terminal tail region and the signal peptide on the recombinant expression of PpuLcc, a non-modified version or different truncations (-2, -5, -13 AA) of the target protein were combined with different secretion signals. Heterologous expression of codon optimized constructs resulted in extracellular activities of the PpuLcc variants of up to 7000 U L-1 (substrate ABTS) which was six times higher than non-codon optimized constructs. In contrast to previous works, altering the C-terminal end of the protein did not influence kinetic parameters or the rate of expression. The His-Tag purified enzymes showed high temperature optima (50-70 °C) and thermo stability. All of the recombinant variants degraded triarylmethane and azo dyes. Rapid bleaching of β-carotene (E 160a) and the polyene acid norbixin (E 160b) using a laccase was found for the first time. Thus, the enzyme may be useful in decolorizing unwanted polyene pigments, for example from the processing of cheese, bakery, desserts, ice cream or coloured casings.
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12
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Giacobelli VG, Monza E, Fatima Lucas M, Pezzella C, Piscitelli A, Guallar V, Sannia G. Repurposing designed mutants: a valuable strategy for computer-aided laccase engineering – the case of POXA1b. Catal Sci Technol 2017. [DOI: 10.1039/c6cy02410f] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The broad specificity of laccases, a direct consequence of their shallow binding site, makes this class of enzymes a suitable template to build specificity toward putative substrates.
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Affiliation(s)
| | - Emanuele Monza
- Joint BSC-CRG-IRB Research Program in Computational Biology
- Barcelona Supercomputing Center
- 08034 Barcelona
- Spain
| | - M. Fatima Lucas
- Joint BSC-CRG-IRB Research Program in Computational Biology
- Barcelona Supercomputing Center
- 08034 Barcelona
- Spain
| | - Cinzia Pezzella
- Department of Chemical Sciences
- University of Naples Federico II
- 80126 Naples
- Italy
| | | | - Victor Guallar
- Joint BSC-CRG-IRB Research Program in Computational Biology
- Barcelona Supercomputing Center
- 08034 Barcelona
- Spain
- Institució Catalana de Recerca i Estudis Avançats (ICREA)
| | - Giovanni Sannia
- Department of Chemical Sciences
- University of Naples Federico II
- 80126 Naples
- Italy
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13
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Abstract
Laccases are multi-copper oxidoreductases which catalyze the oxidation of a wide range of substrates during the simultaneous reduction of oxygen to water. These enzymes, originally found in fungi, plants, and other natural sources, have many industrial and biotechnological applications. They are used in the food, textile, pulp, and paper industries, as well as for bioremediation purposes. Although natural hosts can provide relatively high levels of active laccases after production optimization, heterologous expression can bring, moreover, engineered enzymes with desired properties, such as different substrate specificity or improved stability. Hence, diverse hosts suitable for laccase production are reviewed here, while the greatest emphasis is placed on yeasts which are commonly used for industrial production of various proteins. Different approaches to optimize the laccase expression and activity are also discussed in detail here.
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Affiliation(s)
- Zuzana Antošová
- Department of Membrane Transport, Institute of Physiology, Czech Academy of Sciences (CAS), Vídeňská 1083, 142 20, Prague 4, Czech Republic.
| | - Hana Sychrová
- Department of Membrane Transport, Institute of Physiology, Czech Academy of Sciences (CAS), Vídeňská 1083, 142 20, Prague 4, Czech Republic.
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Functional expression, production, and biochemical characterization of a laccase using yeast surface display technology. Fungal Biol 2016; 120:1609-1622. [PMID: 27890094 DOI: 10.1016/j.funbio.2016.08.009] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Revised: 08/15/2016] [Accepted: 08/19/2016] [Indexed: 01/12/2023]
Abstract
A Trametes versicolor laccase was functionally expressed on the membrane surface of Saccharomyces cerevisiae EBY100. Laccase expression was increased 6.57-fold by medium optimization and surpassed production by the native strain. Maximal laccase and biomass production reached 19 735 ± 1719 Ug-1 and 6.22 ± 0.53 gL-1 respectively, after 2 d of culture. Optimum oxidization of all substrates by laccase was observed at pH 3. Laccase showed high affinity towards substrates used with Km (mM) and Vmax (μmol min-1) values of 0.57 ± 0.0047 and 24.55 ± 0.64, 1.52 ± 0.52 and 9.25 ± 1.78, and 2.67 ± 0.12 and 11.26 ± 0.75, were reported for ABTS, 2, 6-DMP and GUA, respectively. EDTA and NaN3 displayed none competitive inhibition towards laccase activity. The optimum temperature for activity was 50 °C; however, the enzyme was stable over a wide range of temperatures (25-70 °C). The biologically immobilized laccase showed high reusability towards phenolic substrates and low reusability with non-phenolic substrates. High affinity for a diversity phenolic compounds and great ethanol tolerance substantiates this laccase/yeast biocatalyst potential for application in the production of bioethanol.
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15
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Homologous and Heterologous Expression of Basidiomycete Genes Related to Plant Biomass Degradation. Fungal Biol 2016. [DOI: 10.1007/978-3-319-27951-0_5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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16
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Biochemical and molecular characterization of laccase isoforms produced by the white-rot fungus Trametes versicolor under submerged culture conditions. ACTA ACUST UNITED AC 2015. [DOI: 10.1016/j.molcatb.2015.10.009] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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17
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Sitarz AK, Mikkelsen JD, Meyer AS. Structure, functionality and tuning up of laccases for lignocellulose and other industrial applications. Crit Rev Biotechnol 2015; 36:70-86. [DOI: 10.3109/07388551.2014.949617] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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18
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Li J, Lawton TJ, Kostecki JS, Nisthal A, Fang J, Mayo SL, Rosenzweig AC, Jewett MC. Cell‐free protein synthesis enables high yielding synthesis of an active multicopper oxidase. Biotechnol J 2015; 11:212-8. [DOI: 10.1002/biot.201500030] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2015] [Revised: 06/26/2015] [Accepted: 07/31/2015] [Indexed: 12/22/2022]
Affiliation(s)
- Jian Li
- Department of Chemical and Biological Engineering Northwestern University Evanston IL USA
- Chemistry of Life Processes Institute Northwestern University Evanston IL USA
- Robert H. Lurie Comprehensive Cancer Center Northwestern University Chicago IL USA
- Simpson Querrey Institute for BioNanotechnology in Medicine Northwestern University Chicago IL USA
| | - Thomas J. Lawton
- Department of Molecular Biosciences Northwestern University Evanston IL USA
| | - Jan S. Kostecki
- Division of Biological Sciences California Institute of Technology Pasadena CA USA
| | - Alex Nisthal
- Division of Biological Sciences California Institute of Technology Pasadena CA USA
| | - Jia Fang
- Department of Molecular Biosciences Northwestern University Evanston IL USA
| | - Stephen L. Mayo
- Division of Biological Sciences California Institute of Technology Pasadena CA USA
| | - Amy C. Rosenzweig
- Robert H. Lurie Comprehensive Cancer Center Northwestern University Chicago IL USA
- Department of Molecular Biosciences Northwestern University Evanston IL USA
- Department of Chemistry Northwestern University Evanston IL USA
| | - Michael C. Jewett
- Department of Chemical and Biological Engineering Northwestern University Evanston IL USA
- Chemistry of Life Processes Institute Northwestern University Evanston IL USA
- Robert H. Lurie Comprehensive Cancer Center Northwestern University Chicago IL USA
- Simpson Querrey Institute for BioNanotechnology in Medicine Northwestern University Chicago IL USA
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19
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Statistical Optimization of Laccase Production and Delignification of Sugarcane Bagasse by Pleurotus ostreatus in Solid-State Fermentation. BIOMED RESEARCH INTERNATIONAL 2015; 2015:181204. [PMID: 26180784 PMCID: PMC4477062 DOI: 10.1155/2015/181204] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Revised: 02/17/2015] [Accepted: 02/17/2015] [Indexed: 11/17/2022]
Abstract
Laccases are oxidative enzymes related to the degradation of phenolic compounds, including lignin units, with concomitant reduction of oxygen to water. Delignification is a necessary pretreatment step in the process of converting plant biomass into fermentable sugars. The objective of this work was to optimize the production of laccases and to evaluate the delignification of sugarcane bagasse by Pleurotus ostreatus in solid-state fermentation. Among eight variables (pH, water activity, temperature, and concentrations of CuSO4, (NH4)2SO4, KH2PO4, asparagine, and yeast extract), copper sulfate and ammonium sulfate concentrations were demonstrated to significantly influence laccase production. The replacement of ammonium sulfate by yeast extract and the addition of ferulic acid as inducer provided increases of 5.7- and 2.0-fold, respectively, in laccase activity. Optimization of laccase production as a function of yeast extract, copper sulfate, and ferulic acid concentrations was performed by response surface methodology and optimal concentrations were 6.4 g/L, 172.6 μM, and 1.86 mM, respectively. Experimentally, the maximum laccase activity of 151.6 U/g was produced at the 5th day of solid-state fermentation. Lignin content in sugarcane bagasse was reduced from 31.89% to 26.36% after 5 days and to 20.79% after 15 days by the biological treatment of solid-state fermentation.
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Delfino I, Viola D, Cerullo G, Lepore M. Ultrafast excited-state charge-transfer dynamics in laccase type I copper site. Biophys Chem 2015; 200-201:41-7. [PMID: 25819432 DOI: 10.1016/j.bpc.2015.03.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2015] [Revised: 03/09/2015] [Accepted: 03/09/2015] [Indexed: 11/27/2022]
Abstract
Femtosecond pump-probe spectroscopy was used to investigate the excited state dynamics of the T1 copper site of laccase from Pleurotus ostreatus, by exciting its 600 nm charge transfer band with a 15-fs pulse and probing over a broad range in the visible region. The decay of the pump-induced ground-state bleaching occurs in a single step and is modulated by clearly visible oscillations. Global analysis of the two-dimensional differential transmission map shows that the excited state exponentially decays with a time constant of 375 fs, thus featuring a decay rate slower than those occurring in quite all the investigated T1 copper site proteins. The ultrashort pump pulse induces a vibrational coherence in the protein, which is mainly assigned to ground state activity, as expected in a system with fast excited state decay. Vibrational features are discussed also in comparison with the traditional resonance Raman spectrum of the enzyme. The results indicate that both excited state dynamics and vibrational modes associated with the T1 Cu laccase charge transfer have main characteristics similar to those of all the T1 copper site-containing proteins. On the other hand, the differences observed for laccase from P. ostreatus further confirm the peculiar hypothesized trigonal T1 Cu site geometry.
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Affiliation(s)
- Ines Delfino
- Dipartimento di Scienze Ecologiche e Biologiche, Università della Tuscia, Largo dell'Università snc, I-01100 Viterbo, Italy.
| | - Daniele Viola
- IFN-CNR, Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, I-20133 Milano, Italy
| | - Giulio Cerullo
- IFN-CNR, Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, I-20133 Milano, Italy
| | - Maria Lepore
- Dipartimento di Medicina Sperimentale, Seconda Università di Napoli, Via Costantinopoli 16, I-80100 Napoli, Italy
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Laccase engineering by rational and evolutionary design. Cell Mol Life Sci 2015; 72:897-910. [PMID: 25586560 PMCID: PMC4323517 DOI: 10.1007/s00018-014-1824-8] [Citation(s) in RCA: 69] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2014] [Accepted: 12/30/2014] [Indexed: 11/27/2022]
Abstract
Laccases are considered as green catalysts of great biotechnological potential. This has attracted a great interest in designing laccases a la carte with enhanced stabilities or activities tailored to specific conditions for different fields of application. Over 20 years, numerous efforts have been taken to engineer these multicopper oxidases and to understand their reaction mechanisms by site-directed mutagenesis, and more recently, using computational calculations and directed evolution tools. In this work, we review the most relevant contributions made in the field of laccase engineering, from the comprehensive study of their structure–function relationships to the tailoring of outstanding biocatalysts.
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22
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Joshi S, Satyanarayana T. In vitro engineering of microbial enzymes with multifarious applications: prospects and perspectives. BIORESOURCE TECHNOLOGY 2015; 176:273-283. [PMID: 25435065 DOI: 10.1016/j.biortech.2014.10.151] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2014] [Revised: 10/28/2014] [Accepted: 10/29/2014] [Indexed: 06/04/2023]
Abstract
The discovery of a novel enzyme from a microbial source takes anywhere between months to years, and therefore, there has been an immense interest in modifying the existing microbial enzymes to suit the present day needs of the industry. The redesigning of industrially useful enzymes for improving their performance has become a challenge because bioinformatics databases have been revealing new facts on a day-to-day basis. Modification of the existing enzymes has become a trend for fine tuning of biocatalysts in the biotech industry. Hydrolases are employed in pharmaceutical, biofuel, detergent, food and feed industries that significantly contribute to the global annual revenue, and therefore, the emphasis has been on engineering them. Although a large data is accumulating on making alterations in microbial enzymes, there is a lack of definite information on redesigning industrial enzymes. This review focuses on the recent developments in improving the characteristics of various biotechnologically important enzymes.
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Affiliation(s)
- Swati Joshi
- Department of Microbiology, University of Delhi South Campus, Benito Juarez Road, New Delhi 110 021, India
| | - Tulasi Satyanarayana
- Department of Microbiology, University of Delhi South Campus, Benito Juarez Road, New Delhi 110 021, India.
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23
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Hu M, Zhou X, Shi Y, Lin J, Irfan M, Tao Y. Essential Role of the N- and C-terminals of Laccase from Pleurotus florida on the Laccase Activity and Stability. Appl Biochem Biotechnol 2014; 174:2007-17. [DOI: 10.1007/s12010-014-1147-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2014] [Accepted: 08/13/2014] [Indexed: 11/30/2022]
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24
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Liu Y, Cusano AM, Wallace EC, Mekmouche Y, Ullah S, Robert V, Tron T. Characterization of C-terminally engineered laccases. Int J Biol Macromol 2014; 69:435-41. [DOI: 10.1016/j.ijbiomac.2014.05.053] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2014] [Revised: 05/16/2014] [Accepted: 05/20/2014] [Indexed: 10/25/2022]
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25
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Mogharabi M, Faramarzi MA. Laccase and Laccase-Mediated Systems in the Synthesis of Organic Compounds. Adv Synth Catal 2014. [DOI: 10.1002/adsc.201300960] [Citation(s) in RCA: 183] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/07/2022]
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26
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Macellaro G, Baratto MC, Piscitelli A, Pezzella C, Fabrizi de Biani F, Palmese A, Piumi F, Record E, Basosi R, Sannia G. Effective mutations in a high redox potential laccase from Pleurotus ostreatus. Appl Microbiol Biotechnol 2014; 98:4949-61. [PMID: 24463760 DOI: 10.1007/s00253-013-5491-8] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2013] [Revised: 12/16/2013] [Accepted: 12/22/2013] [Indexed: 10/25/2022]
Abstract
Since the first report on a laccase, there has been a notable development in the interest towards this class of enzymes, highlighted from the number of scientific papers and patents about them. At the same time, interest in exploiting laccases-mainly high redox potential-for various functions has been growing exponentially over the last 10 years. Despite decades of work, the molecular determinants of the redox potential are far to be fully understood. For this reason, interest in tuning laccase redox potential to provide more efficient catalysts has been growing since the last years. The work herein described takes advantage of the filamentous fungus Aspergillus niger as host for the heterologous production of the high redox potential laccase POXA1b from Pleurotus ostreatus and of one of its in vitro selected variants (1H6C). The system herein developed allowed to obtain a production level of 35,000 U/L (583.3 μkat/L) for POXA1b and 60,000 U/L (1,000 μkat/L) for 1H6C, corresponding to 13 and 20 mg/L for POXA1b and 1H6C, respectively. The characterised proteins exhibit very similar characteristics, with some exceptions regarding catalytic behaviour, stability and spectro-electrochemical properties. Remarkably, the 1H6C variant shows a higher redox potential with respect to POXA1b. Furthermore, the spectro-electrochemical results obtained for 1H6C make it tempting to claim that we spectro-electrochemically determined the redox potential of the 1H6C T2 site, which has not been studied in any detail by spectro-electrochemistry yet.
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Affiliation(s)
- Gemma Macellaro
- Department of Chemical Sciences, University of Naples "Federico II", Complesso Universitario Monte S. Angelo, via Cinthia 4, 80126, Naples, Italy
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27
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Construction of a Laccase Chimerical Gene: Recombinant Protein Characterization and Gene Expression via Yeast Surface Display. Appl Biochem Biotechnol 2014; 172:2916-31. [DOI: 10.1007/s12010-014-0734-4] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2013] [Accepted: 01/09/2014] [Indexed: 10/25/2022]
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28
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Stability mechanisms of a thermophilic laccase probed by molecular dynamics. PLoS One 2013; 8:e61985. [PMID: 23658618 PMCID: PMC3639223 DOI: 10.1371/journal.pone.0061985] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2012] [Accepted: 03/15/2013] [Indexed: 11/25/2022] Open
Abstract
Laccases are highly stable, industrially important enzymes capable of oxidizing a large range of substrates. Causes for their stability are, as for other proteins, poorly understood. In this work, multiple-seed molecular dynamics (MD) was applied to a Trametes versicolor laccase in response to variable ionic strengths, temperatures, and glycosylation status. Near-physiological conditions provided excellent agreement with the crystal structure (average RMSD ∼0.92 Å) and residual agreement with experimental B-factors. The persistence of backbone hydrogen bonds was identified as a key descriptor of structural response to environment, whereas solvent-accessibility, radius of gyration, and fluctuations were only locally relevant. Backbone hydrogen bonds decreased systematically with temperature in all simulations (∼9 per 50 K), probing structural changes associated with enthalpy-entropy compensation. Approaching Topt (∼350 K) from 300 K, this change correlated with a beginning “unzipping” of critical β-sheets. 0 M ionic strength triggered partial denucleation of the C-terminal (known experimentally to be sensitive) at 400 K, suggesting a general salt stabilization effect. In contrast, F− (but not Cl−) specifically impaired secondary structure by formation of strong hydrogen bonds with backbone NH, providing a mechanism for experimentally observed small anion destabilization, potentially remedied by site-directed mutagenesis at critical intrusion sites. N-glycosylation was found to support structural integrity by increasing persistent backbone hydrogen bonds by ∼4 across simulations, mainly via prevention of F− intrusion. Hydrogen-bond loss in distinct loop regions and ends of critical β-sheets suggest potential strategies for laboratory optimization of these industrially important enzymes.
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Bleve G, Lezzi C, Spagnolo S, Tasco G, Tufariello M, Casadio R, Mita G, Rampino P, Grieco F. Role of the C-terminus of Pleurotus eryngii Ery4 laccase in determining enzyme structure, catalytic properties and stability. Protein Eng Des Sel 2012; 26:1-13. [DOI: 10.1093/protein/gzs056] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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30
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Kumar VV, Sathyaselvabala V, Premkumar M, Vidyadevi T, Sivanesan S. Biochemical characterization of three phase partitioned laccase and its application in decolorization and degradation of synthetic dyes. ACTA ACUST UNITED AC 2012. [DOI: 10.1016/j.molcatb.2011.08.015] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Piscitelli A, Pezzella C, Giardina P, Faraco V, Giovanni S. Heterologous laccase production and its role in industrial applications. Bioeng Bugs 2011; 1:252-62. [PMID: 21327057 DOI: 10.4161/bbug.1.4.11438] [Citation(s) in RCA: 100] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2009] [Revised: 01/25/2010] [Accepted: 01/27/2010] [Indexed: 02/04/2023] Open
Abstract
Laccases are blue multicopper oxidases, catalyzing the oxidation of an array of aromatic substrates concomitantly with the reduction of molecular oxygen to water. These enzymes are implicated in a variety of biological activities. Most of the laccases studied thus far are of fungal origin. The large range of substrates oxidized by laccases has raised interest in using them within different industrial fields, such as pulp delignification, textile dye bleaching, and bioremediation. Laccases secreted from native sources are usually not suitable for large-scale purposes, mainly due to low production yields and high cost of preparation/purification procedures. Heterologous expression may provide higher enzyme yields and may permit to produce laccases with desired properties (such as different substrate specificities, or improved stabilities) for industrial applications. This review surveys researches on heterologous laccase expression focusing on the pivotal role played by recombinant systems towards the development of robust tools for greening modern industry.
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Affiliation(s)
- Alessandra Piscitelli
- Dipartimento di Chimica Organica e Biochimica, Complesso Universitario Monte S. Angelo, Napoli, Italy.
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Miele A, Giardina P, Notomista E, Piscitelli A, Sannia G, Faraco V. A semi-rational approach to engineering laccase enzymes. Mol Biotechnol 2010; 46:149-56. [PMID: 20467838 DOI: 10.1007/s12033-010-9289-y] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In order to develop improved laccase-based bio-catalysts, semi-rational mutagenesis of the laccase POXA1b from Pleurotus ostreatus was performed through a combination of directed evolution with elements of rational enzyme modification. The R4 laccase was prepared by joining mutations of previously selected POXA1b random variants. An enhancement of stability features was thus obtained, making the novel enzyme R4 more appropriate as scaffold for directed evolution. A library of 1000 randomly mutated variants of R4 was prepared and screened for the ability of oxidising 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS). One of the variants selected (V148L) for improved activity was also proved to show higher stability than R4 at pH 5, and to retain its high stability at pH 7 and 10. In comparison with the POXA1b wild-type laccase, the semi-rational approach allowed us to develop a more efficient bio-catalyst, rising specific activity on ABTS up to around 5-fold. The new variant was also proved to be both more versatile and more durable than the wild-type enzyme, exhibiting higher activity in wide temperature and pH ranges and higher stability at acidic (t (1/2) at pH 5 = 35 days), neutral (t (1/2) at pH 7 = 38 days) and alkaline (t (1/2) at pH 10 = 62 days) pH values.
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Affiliation(s)
- Annalisa Miele
- Department of Organic Chemistry and Biochemistry, University of Naples Federico II, Complesso Universitario Monte S. Angelo, via Cintia, 4, 80126, Naples, Italy
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