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Zhang K, Li J, Wang Z, Xie B, Xiong Z, Li H, Ahmed M, Fang F, Li J, Li X. Cloning, expression and application of a novel laccase derived from water buffalo ruminal lignin-degrading bacteria. Int J Biol Macromol 2024; 266:131109. [PMID: 38531520 DOI: 10.1016/j.ijbiomac.2024.131109] [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: 09/27/2023] [Revised: 01/05/2024] [Accepted: 03/21/2024] [Indexed: 03/28/2024]
Abstract
Water buffalo is the only mammal found to degrade lignin so far, and laccase plays an indispensable role in the degradation of lignin. In this study, multiple laccase genes were amplified based on the water buffalo rumen derived lignin-degrading bacteria Bacillus cereus and Ochrobactrum pseudintermedium. Subsequently, the corresponding recombinant plasmids were transformed into E. coli expression system BL21 (DE3) for induced expression by Isopropyl-β-D-thiogalactopyranoside (IPTG). After preliminary screening, protein purification and enzyme activity assays, Lac3833 with soluble expression and high enzyme activity was selected to test its characteristics, especially the ability of lignin degradation. The results showed that the optimum reaction temperature of Lac3833 was 40 °C for different substrates. The relative activity of Lac3833 reached the highest at pH 4.5 and pH 5.5 when the substrates were ABTS or 2,6-DMP and guaiacol, respectively. Additionally, Lac3833 could maintain high enzyme activity in different temperatures, pH and solutions containing Na+, K+, Mg2+, Ca2+ and Mn2+. Importantly, compared to negative treatment, recombinant laccase Lac3833 treatment showed that it had a significant function in degrading lignin. In conclusion, this is a pioneering study to produce recombinant laccase with lignin-degrading ability by bacteria from water buffalo rumen, which will provide new insights for the exploitation of more lignin-degrading enzymes.
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Affiliation(s)
- Kun Zhang
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Jingfa Li
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Zhen Wang
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Bohan Xie
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Zixiang Xiong
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Hongyi Li
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Mehboob Ahmed
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Fang Fang
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, China
| | - Jiakui Li
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, Hubei, China.
| | - Xiang Li
- Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction, Ministry of Education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, Hubei, China; Shennongjia Science and Technology Innovation Center, Huazhong Agricultural University, Shennongjia, China.
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Wang J, Yin R, Hashizume Y, Todoroki Y, Mori T, Kawagishi H, Hirai H. Ergosterol and Its Metabolites Induce Ligninolytic Activity in the Lignin-Degrading Fungus Phanerochaete sordida YK-624. J Fungi (Basel) 2023; 9:951. [PMID: 37755059 PMCID: PMC10532932 DOI: 10.3390/jof9090951] [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: 08/29/2023] [Revised: 09/19/2023] [Accepted: 09/19/2023] [Indexed: 09/28/2023] Open
Abstract
White-rot fungi are the most important group of lignin biodegraders. Phanerochaete sordida YK-624 has higher ligninolytic activity than that of model white-rot fungi. However, the underlying mechanism responsible for lignin degradation by white-rot fungi remains unknown, and the induced compounds isolated from white-rot fungi for lignin degradation have never been studied. In the present study, we tried to screen ligninolytic-inducing compounds produced by P. sordida YK-624. After large-scale incubation of P. sordida YK-624, the culture and mycelium were separated by filtration. After the separation and purification, purified compounds were analyzed by high-resolution electrospray ionization mass spectrometry and nuclear magnetic resonance. The sterilized unbleached hardwood kraft pulp was used for the initial evaluation of ligninolytic activity. Ergosterol was isolated and identified and it induced the lignin-degrading activity of this fungus. Moreover, we investigated ergosterol metabolites from P. sordida YK-624, and the ergosterol metabolites ergosta-4,7,22-triene-3,6-dione and ergosta-4,6,8(14),22-tetraen-3-one were identified and then chemically synthesized. These compounds significantly improved the lignin-degrading activity of the fungus. This is the first report on the ligninolytic-inducing compounds produced by white-rot fungi.
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Affiliation(s)
- Jianqiao Wang
- Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, School of Environmental Science and Engineering, Guangzhou University, Guangzhou 510006, China;
| | - Ru Yin
- Graduate School of Science and Technology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka 422-8529, Japan;
| | - Yuki Hashizume
- Faculty of Agriculture, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka 422-8529, Japan; (Y.H.); (Y.T.); (T.M.); (H.K.)
| | - Yasushi Todoroki
- Faculty of Agriculture, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka 422-8529, Japan; (Y.H.); (Y.T.); (T.M.); (H.K.)
- Research Institute of Green Science and Technology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka 422-8529, Japan
| | - Toshio Mori
- Faculty of Agriculture, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka 422-8529, Japan; (Y.H.); (Y.T.); (T.M.); (H.K.)
- Research Institute for Mushroom Science, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka 422-8529, Japan
| | - Hirokazu Kawagishi
- Faculty of Agriculture, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka 422-8529, Japan; (Y.H.); (Y.T.); (T.M.); (H.K.)
- Research Institute for Mushroom Science, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka 422-8529, Japan
| | - Hirofumi Hirai
- Research Institute of Green Science and Technology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka 422-8529, Japan
- Research Institute for Mushroom Science, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka 422-8529, Japan
- Faculty of Global Interdisciplinary Science and Innovation, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka 422-8529, Japan
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3
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Properties, Physiological Functions and Involvement of Basidiomycetous Alcohol Oxidase in Wood Degradation. Int J Mol Sci 2022; 23:ijms232213808. [PMID: 36430286 PMCID: PMC9699415 DOI: 10.3390/ijms232213808] [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: 09/29/2022] [Revised: 11/04/2022] [Accepted: 11/06/2022] [Indexed: 11/11/2022] Open
Abstract
Extensive research efforts have been devoted to describing yeast alcohol oxidase (AO) and its promoter region, which is vastly applied in studies of heterologous gene expression. However, little is known about basidiomycetous AO and its physiological role in wood degradation. This review describes several alcohol oxidases from both white and brown rot fungi, highlighting their physicochemical and kinetic properties. Moreover, the review presents a detailed analysis of available AO-encoding gene promoter regions in basidiomycetous fungi with a discussion of the manipulations of culture conditions in relation to the modification of alcohol oxidase gene expression and changes in enzyme production. The analysis of reactions catalyzed by lignin-modifying enzymes (LME) and certain lignin auxiliary enzymes (LDA) elucidated the possible involvement of alcohol oxidase in the degradation of derivatives of this polymer. Combined data on lignin degradation pathways suggest that basidiomycetous AO is important in secondary reactions during lignin decomposition by wood degrading fungi. With numerous alcoholic substrates, the enzyme is probably engaged in a variety of catalytic reactions leading to the detoxification of compounds produced in lignin degradation processes and their utilization as a carbon source by fungal mycelium.
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Atiwesh G, Parrish CC, Banoub J, Le TAT. Lignin degradation by microorganisms: A review. Biotechnol Prog 2021; 38:e3226. [PMID: 34854261 DOI: 10.1002/btpr.3226] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2021] [Revised: 11/19/2021] [Accepted: 11/28/2021] [Indexed: 11/09/2022]
Abstract
Lignin is an abundant plant-based biopolymer that has found applications in a variety of industries from construction to bioethanol production. This recalcitrant branched polymer is naturally degraded by many different species of microorganisms, including fungi and bacteria. These microbial lignin degradation mechanisms provide a host of possibilities to overcome the challenges of using harmful chemicals to degrade lignin biowaste in many industries. The classes and mechanisms of different microbial lignin degradation options available in nature form the primary focus of the present review. This review first discusses the chemical building blocks of lignin and the industrial sources and applications of this multifaceted polymer. The review further places emphasis on the degradation of lignin by natural means, discussing in detail the lignin degradation activities of various fungal and bacterial species. The lignin-degrading enzymes produced by various microbial species, specifically white-rot fungi, brown-rot fungi, and bacteria, are described. In the end, possible directions for future lignin biodegradation applications and research investigations have been provided.
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Affiliation(s)
- Ghada Atiwesh
- Environmental Science Program, Memorial University of Newfoundland. St. John's, St. John's, Newfoundland, Canada
| | - Christopher C Parrish
- Chemistry Department, Memorial University of Newfoundland St. John's, St. John's, Newfoundland, Canada.,Department of Ocean Sciences, Memorial University of Newfoundland St. John's, St. John's, Newfoundland, Canada
| | - Joseph Banoub
- Chemistry Department, Memorial University of Newfoundland St. John's, St. John's, Newfoundland, Canada.,Fisheries and Oceans Canada, Science Branch, Special Projects, St John's, Newfoundland, Canada
| | - Tuyet-Anh T Le
- School of Science and the Environment, Memorial University of Newfoundland, St. John's, Newfoundland, Canada.,Environmental Policy Institute, Memorial University of Newfoundland, St. John's, Newfoundland, Canada.,Forestry Economics Research Centre, Vietnamese Academy of Forest Sciences, Hanoi, Vietnam
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5
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García-Esquivel Y, Mercado-Flores Y, Anducho-Reyes MA, Álvarez-Cervantes J, Wobeser EAV, Marina-Ramírez AI, Téllez-Jurado A. 3-Methyl-2-benzothiazolinone hydrazone and 3-dimethylamino benzoic acid as substrates for the development of polyphenoloxidase and phenoloxidase activity by zymograms. 3 Biotech 2021; 11:39. [PMID: 33479594 PMCID: PMC7794263 DOI: 10.1007/s13205-020-02622-6] [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: 08/06/2020] [Accepted: 12/26/2020] [Indexed: 10/22/2022] Open
Abstract
In the present study, a sequential staining process of polyphenoloxidase and phenoloxidase enzymes was designed by the zymography technique. As a first step, electrophoresis was carried out under native conditions, and later, first staining was carried out with a revealing solution of 3-methyl-2-benzothiazoline hydrazone (MBTH)-3-dimethylamino benzoic acid (DMAB) that allowed the visualization of polyphenoloxidase enzymes, and later and using the same gel, we proceeded to the differential staining of phenoloxidase, adding a solution of H2O2. The technique was standardized using commercial enzymes of laccase (T. versicolor) and horseradish. The technique was used to identify polyphenoloxidases (laccases) and phenoloxidases (lignin peroxidase) of crude extracts obtained from the growth of the basidiomycete Lentinus strigosus on Pinus radiata. The technique showed great sensitivity to detect the different enzymatic activities (1.56 Activity Unit/mL minimum) in the same gel without interference between the enzymes and the solutions used. On the other hand, the efficiency of the technique was compared with the substrates that are commonly used for the detection of this type of activities such as 2,2'-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) and guaiacol, observing greater sensitivity and minimal interference, so that the present method will allow in the same gel, and visualize polyphenoloxidase and phenoloxidase activities simultaneously facilitating expression studies.
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Affiliation(s)
- Y. García-Esquivel
- Laboratorio de AgroBiotecnología, Universidad Politécnica de Pachuca, Carretera Pachuca-Cd. Sahagún, km 20, ExHacienda de Santa Bárbara, C.P. 43830 Zempoala, Hidalgo México
| | - Y. Mercado-Flores
- Laboratorio de AgroBiotecnología, Universidad Politécnica de Pachuca, Carretera Pachuca-Cd. Sahagún, km 20, ExHacienda de Santa Bárbara, C.P. 43830 Zempoala, Hidalgo México
| | - M. A. Anducho-Reyes
- Laboratorio de AgroBiotecnología, Universidad Politécnica de Pachuca, Carretera Pachuca-Cd. Sahagún, km 20, ExHacienda de Santa Bárbara, C.P. 43830 Zempoala, Hidalgo México
| | - J. Álvarez-Cervantes
- Laboratorio de AgroBiotecnología, Universidad Politécnica de Pachuca, Carretera Pachuca-Cd. Sahagún, km 20, ExHacienda de Santa Bárbara, C.P. 43830 Zempoala, Hidalgo México
| | - E. Aguirre-von Wobeser
- Cátedras CONACyT, Centro de Investigación en Alimentos y Desarrollo A.C., Centro de Investigación en Agrobiotecnología Alimentaria, Cd. del Conocimiento, Boulevard Circuito La Concepción, C.P. 42162 San Agustín Tlaxiaca, Hidalgo México
| | - A. I. Marina-Ramírez
- Proteómica, Centro de Biología Molecular Severo Ochoa, Nicolás Cabrera No. 1, C.P. 28049 Madrid, Spain
| | - A. Téllez-Jurado
- Laboratorio de AgroBiotecnología, Universidad Politécnica de Pachuca, Carretera Pachuca-Cd. Sahagún, km 20, ExHacienda de Santa Bárbara, C.P. 43830 Zempoala, Hidalgo México
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Roy A, Jayaprakash A, Rajeswary T R, Annamalai A, Lakshmi PTV. Genome-wide annotation, comparison and functional genomics of carbohydrate-active enzymes in legumes infecting Fusarium oxysporum formae speciales. Mycology 2020; 11:56-70. [PMID: 32128282 PMCID: PMC7033727 DOI: 10.1080/21501203.2019.1706656] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Accepted: 11/25/2019] [Indexed: 11/01/2022] Open
Abstract
Fusarium wilt caused by soil borne ascomycetes fungi Fusarium oxysporum which has host-specific forms known as formae speciales (ff. spp.), apparently requires plant cell wall degrading enzymes (PCWDE) for successful invasion. In this study, 12 F. oxysporum ff. spp. were taken for genome-wide annotation and comparative analysis of CAZymes, with an assessment of secretory PCWDE and orthologues identification in the three legumes infecting ff. spp. Further, transcriptomic analysis in two legumes infecting ff. spp. using publically available data was also done. The comparative studies showed Glycoside hydrolase (GH) families to be abundant and Principle Component Analysis (PCA) formed two distinct clusters of ff. spp. based on the CAZymes modules and families. Nearly half of the CAZymes in the legumes infecting ff. spp. coded for signal peptides. The orthologue clusters of secretory CAZymes common in all the three legume infecting ff. spp. mostly belonged to families of AA9, GH28, CE5 and PL1 and the expression analysis revealed the abundant PCWDE were differentially expressed in these legumes infecting ff. spp. Therefore, this study gave an insight into the distribution of CAZymes especially extracellular PCWDE in legumes infecting ff. spp. with further shedding light onto some of the key PCWDE families through differential expression analysis.
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Affiliation(s)
- Abhijeet Roy
- Centre for Bioinformatics, School of Life Sciences, Pondicherry University, Puducherry, India
| | - Aiswarya Jayaprakash
- Centre for Bioinformatics, School of Life Sciences, Pondicherry University, Puducherry, India
| | - Raja Rajeswary T
- Centre for Bioinformatics, School of Life Sciences, Pondicherry University, Puducherry, India
| | - A. Annamalai
- PG and Research Department of Botany, Arignar Anna Government Arts College, Villupuram, India
| | - PTV Lakshmi
- Centre for Bioinformatics, School of Life Sciences, Pondicherry University, Puducherry, India
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Chan JC, Paice M, Zhang X. Enzymatic Oxidation of Lignin: Challenges and Barriers Toward Practical Applications. ChemCatChem 2019. [DOI: 10.1002/cctc.201901480] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Jou C. Chan
- Voiland School of Chemical Engineering and Bioengineering Washington State University 2710 Crimson Way Richland WA-99354 USA
| | - Michael Paice
- FPInnovations Pulp Paper & Bioproducts 2665 East Mall Vancouver BC V6T 1Z4 Canada
| | - Xiao Zhang
- Voiland School of Chemical Engineering and Bioengineering Washington State University 2710 Crimson Way Richland WA-99354 USA
- Pacific Northwest National Laboratory 520 Battelle Boulevard P.O. Box 999, MSIN P8-60 Richland WA-99352 USA
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Microbial β-etherases and glutathione lyases for lignin valorisation in biorefineries: current state and future perspectives. Appl Microbiol Biotechnol 2018; 102:5391-5401. [PMID: 29728724 DOI: 10.1007/s00253-018-9040-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Revised: 04/19/2018] [Accepted: 04/19/2018] [Indexed: 01/05/2023]
Abstract
Lignin is the major aromatic biopolymer in nature, and it is considered a valuable feedstock for the future supply of aromatics. Hence, its valorisation in biorefineries is of high importance, and various chemical and enzymatic approaches for lignin depolymerisation have been reported. Among the enzymes known to act on lignin, β-etherases offer the possibility for a selective cleavage of the β-O-4 aryl ether bonds present in lignin. These enzymes, together with glutathione lyases, catalyse a reductive, glutathione-dependent ether bond cleavage displaying high stereospecificity. β-Etherases and glutathione lyases both belong to the superfamily of glutathione transferases, and several structures have been solved recently. Additionally, different approaches for their application in lignin valorisation have been reported in the last years. This review gives an overview on the current knowledge on β-etherases and glutathione lyases, their biochemical and structural features, and critically discusses their potential for application in biorefineries.
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Gut Microbiome and Putative Resistome of Inca and Italian Nobility Mummies. Genes (Basel) 2017; 8:genes8110310. [PMID: 29112136 PMCID: PMC5704223 DOI: 10.3390/genes8110310] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Revised: 10/20/2017] [Accepted: 10/25/2017] [Indexed: 01/09/2023] Open
Abstract
Little is still known about the microbiome resulting from the process of mummification of the human gut. In the present study, the gut microbiota, genes associated with metabolism, and putative resistome of Inca and Italian nobility mummies were characterized by using high-throughput sequencing. The Italian nobility mummies exhibited a higher bacterial diversity as compared to the Inca mummies when using 16S ribosomal (rRNA) gene amplicon sequencing, but both groups showed bacterial and fungal taxa when using shotgun metagenomic sequencing that may resemble both the thanatomicrobiome and extant human gut microbiomes. Identification of sequences associated with plants, animals, and carbohydrate-active enzymes (CAZymes) may provide further insights into the dietary habits of Inca and Italian nobility mummies. Putative antibiotic-resistance genes in the Inca and Italian nobility mummies support a human gut resistome prior to the antibiotic therapy era. The higher proportion of putative antibiotic-resistance genes in the Inca compared to Italian nobility mummies may support the hypotheses that a greater exposure to the environment may result in a greater acquisition of antibiotic-resistance genes. The present study adds knowledge of the microbiome resulting from the process of mummification of the human gut, insights of ancient dietary habits, and the preserved putative human gut resistome prior the antibiotic therapy era.
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11
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Sana B, Chia KHB, Raghavan SS, Ramalingam B, Nagarajan N, Seayad J, Ghadessy FJ. Development of a genetically programed vanillin-sensing bacterium for high-throughput screening of lignin-degrading enzyme libraries. BIOTECHNOLOGY FOR BIOFUELS 2017; 10:32. [PMID: 28174601 PMCID: PMC5291986 DOI: 10.1186/s13068-017-0720-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2016] [Accepted: 01/28/2017] [Indexed: 05/06/2023]
Abstract
BACKGROUND Lignin is a potential biorefinery feedstock for the production of value-added chemicals including vanillin. A huge amount of lignin is produced as a by-product of the paper industry, while cellulosic components of plant biomass are utilized for the production of paper pulp. In spite of vast potential, lignin remains the least exploited component of plant biomass due to its extremely complex and heterogenous structure. Several enzymes have been reported to have lignin-degrading properties and could be potentially used in lignin biorefining if their catalytic properties could be improved by enzyme engineering. The much needed improvement of lignin-degrading enzymes by high-throughput selection techniques such as directed evolution is currently limited, as robust methods for detecting the conversion of lignin to desired small molecules are not available. RESULTS We identified a vanillin-inducible promoter by RNAseq analysis of Escherichia coli cells treated with a sublethal dose of vanillin and developed a genetically programmed vanillin-sensing cell by placing the 'very green fluorescent protein' gene under the control of this promoter. Fluorescence of the biosensing cell is enhanced significantly when grown in the presence of vanillin and is readily visualized by fluorescence microscopy. The use of fluorescence-activated cell sorting analysis further enhances the sensitivity, enabling dose-dependent detection of as low as 200 µM vanillin. The biosensor is highly specific to vanillin and no major response is elicited by the presence of lignin, lignin model compound, DMSO, vanillin analogues or non-specific toxic chemicals. CONCLUSIONS We developed an engineered E. coli cell that can detect vanillin at a concentration as low as 200 µM. The vanillin-sensing cell did not show cross-reactivity towards lignin or major lignin degradation products including vanillin analogues. This engineered E. coli cell could potentially be used as a host cell for screening lignin-degrading enzymes that can convert lignin to vanillin.
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Affiliation(s)
- Barindra Sana
- p53 Laboratory, Agency for Science Technology And Research (A*STAR), 8A Biomedical Grove, #06-04/05 Neuros/Immunos, Singapore, 138648 Singapore
| | - Kuan Hui Burton Chia
- Genome Institute of Singapore, 60 Biopolis Street, Genome, #02-01, Singapore, 138672 Singapore
| | - Sarada S. Raghavan
- p53 Laboratory, Agency for Science Technology And Research (A*STAR), 8A Biomedical Grove, #06-04/05 Neuros/Immunos, Singapore, 138648 Singapore
| | - Balamurugan Ramalingam
- Institute of Chemical and Engineering Sciences, 8 Biomedical Grove, Neuros, #07-01, Singapore, 138665 Singapore
| | - Niranjan Nagarajan
- Genome Institute of Singapore, 60 Biopolis Street, Genome, #02-01, Singapore, 138672 Singapore
| | - Jayasree Seayad
- Institute of Chemical and Engineering Sciences, 8 Biomedical Grove, Neuros, #07-01, Singapore, 138665 Singapore
| | - Farid J. Ghadessy
- p53 Laboratory, Agency for Science Technology And Research (A*STAR), 8A Biomedical Grove, #06-04/05 Neuros/Immunos, Singapore, 138648 Singapore
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Cotton Stalk Pretreatment Using Daedalea flavida, Phlebia radiata, and Flavodon flavus: Lignin Degradation, Cellulose Recovery, and Enzymatic Saccharification. Appl Biochem Biotechnol 2016; 181:1465-1484. [PMID: 27812899 DOI: 10.1007/s12010-016-2296-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Accepted: 10/18/2016] [Indexed: 10/20/2022]
Abstract
Lignocellulolytic enzyme activities of selective fungi Daedalea flavida MTCC 145 (DF-2), Phlebia radiata MTCC 2791 (PR), and non-selective fungus Flavodon flavus MTCC 168 (FF) were studied for pretreatment of cotton stalks. Simultaneous productions of high LiP and laccase activities by DF-2 during early phase of growth were effective for lignin degradation 27.83 ± 1.25 % (w/w of lignin) in 20-day pretreatment. Production of high MnP activity without laccase in the early growth phase of PR was ineffective and delayed lignin degradation 24.93 ± 1.53 % in 25 days due to laccase production at later phase. With no LiP activity, low activities of MnP and laccase by FF yielded poor lignin degradation 15.09 ± 0.6 % in 20 days. Xylanase was predominant cellulolytic enzyme produced by DF-2, resulting hemicellulose as main carbon and energy source with 83 % of cellulose recovery after 40 days of pretreatment. The glucose yield improved more than two fold from 20-day DF-2 pretreated cotton stalks after enzymatic saccharification.
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Picart P, de María PD, Schallmey A. From gene to biorefinery: microbial β-etherases as promising biocatalysts for lignin valorization. Front Microbiol 2015; 6:916. [PMID: 26388858 PMCID: PMC4560021 DOI: 10.3389/fmicb.2015.00916] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2015] [Accepted: 08/21/2015] [Indexed: 11/13/2022] Open
Abstract
The set-up of biorefineries for the valorization of lignocellulosic biomass will be core in the future to reach sustainability targets. In this area, biomass-degrading enzymes are attracting significant research interest for their potential in the production of chemicals and biofuels from renewable feedstock. Glutathione-dependent β-etherases are emerging enzymes for the biocatalytic depolymerization of lignin, a heterogeneous aromatic polymer abundant in nature. They selectively catalyze the reductive cleavage of β-O-4 aryl-ether bonds which account for 45–60% of linkages present in lignin. Hence, application of β-etherases in lignin depolymerization would enable a specific lignin breakdown, selectively yielding (valuable) low-molecular-mass aromatics. Albeit β-etherases have been biochemically known for decades, only very recently novel β-etherases have been identified and thoroughly characterized for lignin valorization, expanding the enzyme toolbox for efficient β-O-4 aryl-ether bond cleavage. Given their emerging importance and potential, this mini-review discusses recent developments in the field of β-etherase biocatalysis covering all aspects from enzyme identification to biocatalytic applications with real lignin samples.
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Affiliation(s)
- Pere Picart
- Institute of Biotechnology, RWTH Aachen University , Aachen, Germany
| | | | - Anett Schallmey
- Institute for Biochemistry, Biotechnology and Bioinformatics, Technische Universität Braunschweig , Braunschweig, Germany
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