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Gopalakrishnan RM, Manavalan T, Ramesh J, Thangavelu KP, Heese K. Improvement of Saccharification and Delignification Efficiency of Trichoderma reesei Rut-C30 by Genetic Bioengineering. Microorganisms 2020; 8:microorganisms8020159. [PMID: 31979278 PMCID: PMC7074786 DOI: 10.3390/microorganisms8020159] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Revised: 01/20/2020] [Accepted: 01/22/2020] [Indexed: 11/16/2022] Open
Abstract
Trichoderma reesei produces various saccharification enzymes required for biomass degradation. However, the lack of an effective lignin-degrading enzyme system reduces the species’ efficiency in producing fermentable sugars and increases the pre-treatment costs for biofuel production. In this study, we heterologously expressed the Ganoderma lucidum RMK1 versatile peroxidase gene (vp1) in the Rut-C30 strain of T. reesei. The expression of purified 6×His-tag–containing recombinant G. lucidum-derived protein (rVP1) was confirmed through western blot, which exhibited a single band with a relative molecular weight of 39 kDa. In saccharification and delignification studies using rice straw, the transformant (tVP7, T. reesei Rut-C30 expressing G. lucidum-derived rVP1) showed significant improvement in the yield of total reducing sugar and delignification, compared with that of the parent T. reesei Rut-C30 strain. Scanning electron microscopy (SEM) of tVP7-treated paddy straw showed extensive degradation of several layers of its surface compared with the parent strain due to the presence of G. lucidum-derived rVP1. Our results suggest that the expression of ligninolytic enzymes in cellulase hyperproducing systems helps to integrate the pre-treatment and saccharification steps that may ultimately reduce the costs of bioethanol production.
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Affiliation(s)
- Raja Mohan Gopalakrishnan
- Centre for Advanced Studies in Botany, University of Madras, Guindy Campus, Chennai, Tamil Nadu 600 025, India; (R.M.G.); (T.M.)
| | - Tamilvendan Manavalan
- Centre for Advanced Studies in Botany, University of Madras, Guindy Campus, Chennai, Tamil Nadu 600 025, India; (R.M.G.); (T.M.)
| | - Janani Ramesh
- Department of Medical Biochemistry, Dr ALM Postgraduate Institute of Biomedical Sciences, University of Madras, Chennai, Tamil Nadu 600 113, India;
| | - Kalaichelvan Puthupalayam Thangavelu
- Centre for Advanced Studies in Botany, University of Madras, Guindy Campus, Chennai, Tamil Nadu 600 025, India; (R.M.G.); (T.M.)
- Correspondence: (K.P.T.); (K.H.)
| | - Klaus Heese
- Graduate School of Biomedical Science and Engineering, Hanyang University, 222 Wangsimni-ro, Seongdong-gu, Seoul 133-791, Korea
- Correspondence: (K.P.T.); (K.H.)
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Telescopic synthesis of cellulose nanofibrils with a stable dispersion of Fe(0) nanoparticles for synergistic removal of 5-fluorouracil. Sci Rep 2019; 9:11703. [PMID: 31406228 PMCID: PMC6691004 DOI: 10.1038/s41598-019-48274-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Accepted: 08/01/2019] [Indexed: 11/16/2022] Open
Abstract
The recognition of cellulose nanofibrils (CNF) in the past years as a high prospect material has been prominent, but the impractical cellulose extraction method from biomass remained as a technological barrier for industrial practice. In this study, the telescopic approach on the fractionation of lignin and cellulose was performed by organosolv extraction and catalytic oxidation from oil palm empty fruit bunch fibers. The integration of these techniques managed to synthesize CNF in a short time. Aside from the size, the zeta potential of CNF was measured at −41.9 mV, which allow higher stability of the cellulose in water suspension. The stability of CNF facilitated a better dispersion of Fe(0) nanoparticles with the average diameter size of 52.3–73.24 nm through the formulation of CNF/Fe(0). The total uptake capacity of CNF towards 5-fluorouracil was calculated at 0.123 mg/g. While the synergistic reactions of adsorption-oxidation were significantly improved the removal efficacy three to four times greater even at a high concentration of 5-fluorouracil. Alternatively, the sludge generation after the oxidation reaction was completely managed by the encapsulation of Fe(0) nanoparticles in regenerated cellulose.
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Li Y, Liu J, Wang G, Yang M, Yang X, Li T, Chen G. De novo transcriptome analysis of Pleurotus djamor to identify genes encoding CAZymes related to the decomposition of corn stalk lignocellulose. J Biosci Bioeng 2019; 128:529-536. [PMID: 31147217 DOI: 10.1016/j.jbiosc.2019.04.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2018] [Revised: 03/06/2019] [Accepted: 04/15/2019] [Indexed: 12/11/2022]
Abstract
CAZymes play a very important role in the biotransformation of corn stalk biomass, which is an important resource for sustainable development. Pleurotus djamor can produce CAZymes related to the decomposition of corn stalk lignocellulose biomass in sole corn stalk substrate; however, little is known about their encoding genes. In order to identify CAZymes encoding genes, RNA high-throughput sequencing of P. djamor was performed in this study. The results showed that a core set of 70 upregulated genes encoding putative CAZymes were revealed. They encode 19 kinds of CAZymes in total, of which there are 4 EGLs, 8 CBHs, 5 BGLs, and 12 LPMOs related to cellulose degradation, 8 XYNs, 1 XYL, 2 AGUs, 3 ABFs, 2 AGLs, and 2 AXEs related to hemicellulose degradation, and 5 LACCs, 2 MnPs, 5 VPs, 3 CDHs, 1 AAO, 1 GOX, 1 AOX, 2 GAOXs, and 3 GLOXs related to lignin degradation. This variety suggests that CAZymes may play a very important role in decomposing the lignocellulose biomass of corn stalk. This is the first study to report the de novo transcriptome sequencing of P. djamor, which will produce a dataset of genes encoding CAZymes, thereby laying the foundation to elucidate the degradation mechanism of corn stalk biomass and boost the biotransformation of corn stalk biomass resources.
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Affiliation(s)
- Yanli Li
- Engineering Research Center of the Chinese Ministry of Education for Bioreactor and Pharmaceutical Development, College of Life Science, Jilin Agricultural University, Xincheng Street 2888, Nanguan District, Changchun 130118, Jilin, China; Innovation Platform of Jilin Province for Straw Comprehensive Utilization Technology, Jilin Agricultural University, Xincheng Street 2888, Nanguan District, Changchun 130118, Jilin, China; Engineering Research Center of the Chinese Ministry of Education for Edible and Medicinal Fungi, Jilin Agricultural University, Xincheng Street 2888, Nanguan District, Changchun 130118, Jilin, China.
| | - Jiahao Liu
- Engineering Research Center of the Chinese Ministry of Education for Bioreactor and Pharmaceutical Development, College of Life Science, Jilin Agricultural University, Xincheng Street 2888, Nanguan District, Changchun 130118, Jilin, China; Innovation Platform of Jilin Province for Straw Comprehensive Utilization Technology, Jilin Agricultural University, Xincheng Street 2888, Nanguan District, Changchun 130118, Jilin, China
| | - Gang Wang
- Innovation Platform of Jilin Province for Straw Comprehensive Utilization Technology, Jilin Agricultural University, Xincheng Street 2888, Nanguan District, Changchun 130118, Jilin, China
| | - Meiying Yang
- Engineering Research Center of the Chinese Ministry of Education for Bioreactor and Pharmaceutical Development, College of Life Science, Jilin Agricultural University, Xincheng Street 2888, Nanguan District, Changchun 130118, Jilin, China
| | - Xue Yang
- Engineering Research Center of the Chinese Ministry of Education for Bioreactor and Pharmaceutical Development, College of Life Science, Jilin Agricultural University, Xincheng Street 2888, Nanguan District, Changchun 130118, Jilin, China
| | - Tongbing Li
- Innovation Platform of Jilin Province for Straw Comprehensive Utilization Technology, Jilin Agricultural University, Xincheng Street 2888, Nanguan District, Changchun 130118, Jilin, China
| | - Guang Chen
- Innovation Platform of Jilin Province for Straw Comprehensive Utilization Technology, Jilin Agricultural University, Xincheng Street 2888, Nanguan District, Changchun 130118, Jilin, China
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Huang Y, Ren J, Qu X. Nanozymes: Classification, Catalytic Mechanisms, Activity Regulation, and Applications. Chem Rev 2019; 119:4357-4412. [PMID: 30801188 DOI: 10.1021/acs.chemrev.8b00672] [Citation(s) in RCA: 1423] [Impact Index Per Article: 284.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Because of the high catalytic activities and substrate specificity, natural enzymes have been widely used in industrial, medical, and biological fields, etc. Although promising, they often suffer from intrinsic shortcomings such as high cost, low operational stability, and difficulties of recycling. To overcome these shortcomings, researchers have been devoted to the exploration of artificial enzyme mimics for a long time. Since the discovery of ferromagnetic nanoparticles with intrinsic horseradish peroxidase-like activity in 2007, a large amount of studies on nanozymes have been constantly emerging in the next decade. Nanozymes are one kind of nanomaterials with enzymatic catalytic properties. Compared with natural enzymes, nanozymes have the advantages such as low cost, high stability and durability, which have been widely used in industrial, medical, and biological fields. A thorough understanding of the possible catalytic mechanisms will contribute to the development of novel and high-efficient nanozymes, and the rational regulations of the activities of nanozymes are of great significance. In this review, we systematically introduce the classification, catalytic mechanism, activity regulation as well as recent research progress of nanozymes in the field of biosensing, environmental protection, and disease treatments, etc. in the past years. We also propose the current challenges of nanozymes as well as their future research focus. We anticipate this review may be of significance for the field to understand the properties of nanozymes and the development of novel nanomaterials with enzyme mimicking activities.
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Affiliation(s)
- Yanyan Huang
- Laboratory of Chemical Biology and State Key Laboratory of Rare Earth Resource Utilization , Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Changchun , Jilin 130022 , China.,College of Light Industry and Food Engineering , Nanjing Forestry University , Nanjing 210037 , China
| | - Jinsong Ren
- Laboratory of Chemical Biology and State Key Laboratory of Rare Earth Resource Utilization , Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Changchun , Jilin 130022 , China
| | - Xiaogang Qu
- Laboratory of Chemical Biology and State Key Laboratory of Rare Earth Resource Utilization , Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Changchun , Jilin 130022 , China
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Zucca P, Cocco G, Sollai F, Sanjust E. Fungal laccases as tools for biodegradation of industrial dyes. ACTA ACUST UNITED AC 2016. [DOI: 10.1515/boca-2015-0007] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
AbstractLaccases are blue copper oxidases, found in some plants and secreted by a wide range of ligninolytic fungi. These enzymes are well known for their ability in oxidizing several organic compounds, mainly phenolics and aromatic amines, at the expenses of molecular oxygen. Therefore, they could find application in the field of enzymatic bioremediation of many industrial wastewaters, and in particular to bleach and/or detoxify dye-containing effluents. Not all industrial dyes behave as laccase substrates, but this limitation is often overcome by the judicious use of redox mediators. These could substantially widen the application range of laccases as bioremediation tools. The present study encompasses the main properties of the most used industrial dyes as related to their chemical classification, fungal laccases and their molecular and catalytic features, the use of redox mediators, limitations and perspectives of the use of fungal laccases for industrial dye bleaching.
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Sáez-Jiménez V, Fernández-Fueyo E, Medrano FJ, Romero A, Martínez AT, Ruiz-Dueñas FJ. Improving the pH-stability of Versatile Peroxidase by Comparative Structural Analysis with a Naturally-Stable Manganese Peroxidase. PLoS One 2015; 10:e0140984. [PMID: 26496708 PMCID: PMC4619715 DOI: 10.1371/journal.pone.0140984] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2015] [Accepted: 09/04/2015] [Indexed: 11/18/2022] Open
Abstract
Versatile peroxidase (VP) from the white-rot fungus Pleurotus eryngii is a high redox potential peroxidase of biotechnological interest able to oxidize a wide range of recalcitrant substrates including lignin, phenolic and non-phenolic aromatic compounds and dyes. However, the relatively low stability towards pH of this and other fungal peroxidases is a drawback for their industrial application. A strategy based on the comparative analysis of the crystal structures of VP and the highly pH-stable manganese peroxidase (MnP4) from Pleurotus ostreatus was followed to improve the VP pH stability. Several interactions, including hydrogen bonds and salt bridges, and charged residues exposed to the solvent were identified as putatively contributing to the pH stability of MnP4. The eight amino acid residues responsible for these interactions and seven surface basic residues were introduced into VP by directed mutagenesis. Furthermore, two cysteines were also included to explore the effect of an extra disulfide bond stabilizing the distal Ca2+ region. Three of the four designed variants were crystallized and new interactions were confirmed, being correlated with the observed improvement in pH stability. The extra hydrogen bonds and salt bridges stabilized the heme pocket at acidic and neutral pH as revealed by UV-visible spectroscopy. They led to a VP variant that retained a significant percentage of the initial activity at both pH 3.5 (61% after 24 h) and pH 7 (55% after 120 h) compared with the native enzyme, which was almost completely inactivated. The introduction of extra solvent-exposed basic residues and an additional disulfide bond into the above variant further improved the stability at acidic pH (85% residual activity at pH 3.5 after 24 h when introduced separately, and 64% at pH 3 when introduced together). The analysis of the results provides a rational explanation to the pH stability improvement achieved.
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Affiliation(s)
| | | | - Francisco Javier Medrano
- Centro de Investigaciones Biológicas, CSIC, Madrid, Spain
- * E-mail: (FJM, for questions related to obtaining X-ray crystal structures); (ATM); (FJR-D)
| | - Antonio Romero
- Centro de Investigaciones Biológicas, CSIC, Madrid, Spain
| | - Angel T. Martínez
- Centro de Investigaciones Biológicas, CSIC, Madrid, Spain
- * E-mail: (FJM, for questions related to obtaining X-ray crystal structures); (ATM); (FJR-D)
| | - Francisco J. Ruiz-Dueñas
- Centro de Investigaciones Biológicas, CSIC, Madrid, Spain
- * E-mail: (FJM, for questions related to obtaining X-ray crystal structures); (ATM); (FJR-D)
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Sáez-Jiménez V, Acebes S, Guallar V, Martínez AT, Ruiz-Dueñas FJ. Improving the oxidative stability of a high redox potential fungal peroxidase by rational design. PLoS One 2015; 10:e0124750. [PMID: 25923713 PMCID: PMC4414599 DOI: 10.1371/journal.pone.0124750] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2015] [Accepted: 03/05/2015] [Indexed: 11/19/2022] Open
Abstract
Ligninolytic peroxidases are enzymes of biotechnological interest due to their ability to oxidize high redox potential aromatic compounds, including the recalcitrant lignin polymer. However, different obstacles prevent their use in industrial and environmental applications, including low stability towards their natural oxidizing-substrate H2O2. In this work, versatile peroxidase was taken as a model ligninolytic peroxidase, its oxidative inactivation by H2O2 was studied and different strategies were evaluated with the aim of improving H2O2 stability. Oxidation of the methionine residues was produced during enzyme inactivation by H2O2 excess. Substitution of these residues, located near the heme cofactor and the catalytic tryptophan, rendered a variant with a 7.8-fold decreased oxidative inactivation rate. A second strategy consisted in mutating two residues (Thr45 and Ile103) near the catalytic distal histidine with the aim of modifying the reactivity of the enzyme with H2O2. The T45A/I103T variant showed a 2.9-fold slower reaction rate with H2O2 and 2.8-fold enhanced oxidative stability. Finally, both strategies were combined in the T45A/I103T/M152F/M262F/M265L variant, whose stability in the presence of H2O2 was improved 11.7-fold. This variant showed an increased half-life, over 30 min compared with 3.4 min of the native enzyme, under an excess of 2000 equivalents of H2O2. Interestingly, the stability improvement achieved was related with slower formation, subsequent stabilization and slower bleaching of the enzyme Compound III, a peroxidase intermediate that is not part of the catalytic cycle and leads to the inactivation of the enzyme.
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Affiliation(s)
- Verónica Sáez-Jiménez
- Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Sandra Acebes
- Joint Barcelona Supercomputing Center—Centre for Genomic Regulation, Institute for Research in Biomedicine Research Program in Computational Biology, Barcelona Supercomputing Center, Barcelona, Spain
| | - Victor Guallar
- Joint Barcelona Supercomputing Center—Centre for Genomic Regulation, Institute for Research in Biomedicine Research Program in Computational Biology, Barcelona Supercomputing Center, Barcelona, Spain
| | - Angel T. Martínez
- Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas, Madrid, Spain
| | - Francisco J. Ruiz-Dueñas
- Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas, Madrid, Spain
- * E-mail:
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Liu Y, Wang S, Yin Y, Xu F. Evaluation of genetic diversity of Chinese Pleurotus ostreatus cultivars using DNA sequencing technology. ANN MICROBIOL 2012. [DOI: 10.1007/s13213-012-0505-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022] Open
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