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Koubová A, Lorenc F, Horváthová T, Chroňáková A, Šustr V. Millipede gut-derived microbes as a potential source of cellulolytic enzymes. World J Microbiol Biotechnol 2023; 39:169. [PMID: 37186294 DOI: 10.1007/s11274-023-03620-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Accepted: 04/13/2023] [Indexed: 05/17/2023]
Abstract
Lignocellulose biomass has recently been considered a cost-effective and renewable energy source within circular economy management. Cellulases are important key enzymes for simple, fast, and clean biomass decomposition. The intestinal tract of millipedes is the environment which can provide promising microbial strains with cellulolytic potential. In the present study, we used the tropical millipede Telodeinopus aoutii as an experimental organism. Within a feeding test in which millipedes were fed with oak and maple leaf litter, we focused on isolating culturable cellulolytic microbiota from the millipede gut. Several growth media selecting for actinobacteria, bacteria, and fungi have been used to cultivate microbial strains with cellulolytic activities. Our results showed that oak-fed millipedes provided a higher number of culturable bacteria and a more diversified microbial community than maple-fed ones. The screening for cellulolytic activity using Congo red revealed that about 30% of bacterial and fungal phylotypes isolated from the gut content of T. aoutii, produced active cellulases in vitro. Actinobacteria Streptomyces and Kitasatospora were the most active cellulolytic genera on Congo red test. In contrast, fungi Aspergillus, Penicillium, Cheatomium, Clonostachys, and Trichoderma showed the highest protein-specific cellulase activity quantified by 4-Methylumbelliferyl β-D-cellobioside (4-MUC). Our findings provide a basis for future research on the enzyme activities of microbes isolated from the digestive tracts of invertebrates and their biocatalytic role in biomass degradation.
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Affiliation(s)
- Anna Koubová
- Institute of Soil Biology and Biogeochemistry, Biology Centre CAS, Na Sádkách 702/7, 370 05, České Budějovice, Czech Republic
- Faculty of Fisheries and Protection of Waters, South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses, University of South Bohemia in České Budějovice, Zátiší 728/II, 389 25, Vodňany, Czech Republic
| | - František Lorenc
- Institute of Soil Biology and Biogeochemistry, Biology Centre CAS, Na Sádkách 702/7, 370 05, České Budějovice, Czech Republic
- Faculty of Agriculture and Technology, University of South Bohemia in České Budějovice, Studentská 1668, 370 05, České Budějovice, Czech Republic
| | - Terézia Horváthová
- Institute of Soil Biology and Biogeochemistry, Biology Centre CAS, Na Sádkách 702/7, 370 05, České Budějovice, Czech Republic
- EAWAG, Swiss Federal Institute of Aquatic Science and Technology, Überlandstrasse 133, 8600, Dübendorf, Switzerland
| | - Alica Chroňáková
- Institute of Soil Biology and Biogeochemistry, Biology Centre CAS, Na Sádkách 702/7, 370 05, České Budějovice, Czech Republic
| | - Vladimír Šustr
- Institute of Soil Biology and Biogeochemistry, Biology Centre CAS, Na Sádkách 702/7, 370 05, České Budějovice, Czech Republic.
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Li Y, Li T, Guo J, Wang G, Chen G. Expression and characterization of a novel lytic polysaccharide monooxygenase, PdLPMO9A, from the edible fungus Pleurotus djamor and its synergistic interactions with cellulase in corn straw biomass saccharification. BIORESOURCE TECHNOLOGY 2022; 348:126792. [PMID: 35121098 DOI: 10.1016/j.biortech.2022.126792] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 01/26/2022] [Accepted: 01/27/2022] [Indexed: 06/14/2023]
Abstract
Lytic polysaccharide monooxygenases play a unique role in biomass saccharification. A novel gene, PdLPMO9A, from Pleurotus djamor, was reported to be upregulated during the degradation of corn straw in our previous research. However, very little information is available on PdLPMO9A. Therefore, PdLPMO9A was heterologously expressed in Pichia pastoris, and biophysical characterisitics of the recombinant protein PdLPMO9A were investigated; it was shown to have superior thermostability and pH stability. PdLPMO9A markedly improved the cellulase-mediated saccharification of corn straw, when the dosage of PdLPMO9A was 0.66 mg/g corn straw and hydrolysis time was 48 h. When CuSO4 was added at a concentration of 0.1 mM, glucose yield rose by a further 28.16%. In light of these findings, it was concluded that PdLPMO9A has the potential to function as an essential component of a cellulase cocktail capable of ensuring the saccharification of corn straw biomass.
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Affiliation(s)
- Yanli Li
- College of Life Science, Jilin Agricultural University, Jilin 130118, China; Key laboratory of straw comprehensive utilization and black soil conservation, Education Ministry of China, Jilin Agricultural University, Jilin 130118, China.
| | - Tongbing Li
- College of Life Science, Jilin Agricultural University, Jilin 130118, China
| | - Juntong Guo
- College of Life Science, Jilin Agricultural University, Jilin 130118, China
| | - Gang Wang
- College of Life Science, Jilin Agricultural University, Jilin 130118, China; Key laboratory of straw comprehensive utilization and black soil conservation, Education Ministry of China, Jilin Agricultural University, Jilin 130118, China
| | - Guang Chen
- College of Life Science, Jilin Agricultural University, Jilin 130118, China; Key laboratory of straw comprehensive utilization and black soil conservation, Education Ministry of China, Jilin Agricultural University, Jilin 130118, China
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Chen CL, Li WC, Chuang YC, Liu HC, Huang CH, Lo KY, Chen CY, Chang FM, Chang GA, Lin YL, Yang WD, Su CH, Yeh TM, Wang TF. Sexual Crossing, Chromosome-Level Genome Sequences, and Comparative Genomic Analyses for the Medicinal Mushroom Taiwanofungus Camphoratus (Syn. Antrodia Cinnamomea, Antrodia Camphorata). Microbiol Spectr 2022; 10:e0203221. [PMID: 35196809 PMCID: PMC8865532 DOI: 10.1128/spectrum.02032-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Accepted: 01/27/2022] [Indexed: 12/24/2022] Open
Abstract
Taiwanofungus camphoratus mushrooms are a complementary and alternative medicine for hangovers, cancer, hypertension, obesity, diabetes, and inflammation. Though Taiwanofungus camphoratus has attracted considerable biotechnological and pharmacological attention, neither classical genetic nor genomic approaches have been properly established for it. We isolated four sexually competent monokaryons from two T. camphoratus dikaryons used for the commercial cultivation of orange-red (HC1) and milky-white (SN1) mushrooms, respectively. We also sequenced, annotated, and comparatively analyzed high-quality and chromosome-level genome sequences of these four monokaryons. These genomic resources represent a valuable basis for understanding the biology, evolution, and secondary metabolite biosynthesis of this economically important mushrooms. We demonstrate that T. camphoratus has a tetrapolar mating system and that HC1 and SN1 represent two intraspecies isolates displaying karyotypic variation. Compared with several edible mushroom model organisms, T. camphoratus underwent a significant contraction in the gene family and individual gene numbers, most notably for plant, fungal, and bacterial cell-wall-degrading enzymes, explaining why T. camphoratus mushrooms are rare in natural environments, are difficult and time-consuming to artificially cultivate, and are susceptible to fungal and bacterial infections. Our results lay the foundation for an in-depth T. camphoratus study, including precise genetic manipulation, improvements to mushroom fruiting, and synthetic biology applications for producing natural medicinal products. IMPORTANCETaiwanofungus camphoratus (Tc) is a basidiomycete fungus that causes brown heart rot of the aromatic tree Cinnamomum kanehirae. The Tc fruiting bodies have been used to treat hangovers, abdominal pain, diarrhea, hypertension, and other diseases first by aboriginal Taiwanese and later by people in many countries. To establish classical genetic and genomic approaches for this economically important medicinal mushroom, we first isolated and characterized four sexually competent monokaryons from two dikaryons wildly used for commercial production of Tc mushrooms. We applied PacBio single molecule, real-time sequencing technology to determine the near-completed genome sequences of four monokaryons. These telomere-to-telomere and gapless haploid genome sequences reveal all genomic variants needed to be studied and discovered, including centromeres, telomeres, retrotransposons, mating type loci, biosynthetic, and metabolic gene clusters. Substantial interspecies diversities are also discovered between Tc and several other mushroom model organisms, including Agrocybe aegerita, Coprinopsis cinerea, and Schizophyllum commune, and Ganoderma lucidum.
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Affiliation(s)
- Chia-Ling Chen
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Wan-Chen Li
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Yu-Chien Chuang
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Hou-Cheng Liu
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Chien-Hao Huang
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Ko-Yun Lo
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Chung-Yu Chen
- Shen Nong Fungal Biotechnology Co. Ltd., Taoyuan City, Taiwan
| | - Fang-Mo Chang
- School of Dentistry, College of Oral Medicine, Taipei Medical University, Taipei, Taiwan
| | | | | | | | - Ching-Hua Su
- Department of Microbiology and Immunology, Taipei Medical University, Taipei, Taiwan
| | - Tsung-Ming Yeh
- Shen Nong Fungal Biotechnology Co. Ltd., Taoyuan City, Taiwan
| | - Ting-Fang Wang
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
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Sun P, Laurent CVFP, Boerkamp VJP, van Erven G, Ludwig R, van Berkel WJH, Kabel MA. Regioselective C4 and C6 Double Oxidation of Cellulose by Lytic Polysaccharide Monooxygenases. CHEMSUSCHEM 2022; 15:e202102203. [PMID: 34859958 PMCID: PMC9299857 DOI: 10.1002/cssc.202102203] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Revised: 12/01/2021] [Indexed: 06/01/2023]
Abstract
Lytic polysaccharide monooxygenases (LPMOs) play a key role in enzymatic degradation of hard-to-convert polysaccharides, such as chitin and cellulose. It is widely accepted that LPMOs catalyze a single regioselective oxidation of the C1 or C4 carbon of a glycosidic linkage, after which the destabilized linkage breaks. Here, a series of novel C4/C6 double oxidized cello-oligosaccharides was discovered. Products were characterized, aided by sodium borodeuteride reduction and hydrophilic interaction chromatography coupled to mass spectrometric analysis. The C4/C6 double oxidized products were generated by C4 and C1/C4 oxidizing LPMOs, but not by C1 oxidizing ones. By performing incubation and reduction in H2 18 O, it was confirmed that the C6 gem-diol structure resulted from oxygenation, although oxidation to a C6 aldehyde, followed by hydration to the C6 gem-diol, could not be excluded. These findings can be extended to how the reactive LPMO-cosubstrate complex is positioned towards the substrate.
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Affiliation(s)
- Peicheng Sun
- Laboratory of Food ChemistryWageningen University & ResearchBornse Weilanden 96708 WGWageningen (TheNetherlands
| | - Christophe V. F. P. Laurent
- Biocatalysis and Biosensing LaboratoryDepartment of Food Science and TechnologyBOKU-University of Natural Resources and Life SciencesMuthgasse 181190ViennaAustria
- Institute of Molecular Modeling and SimulationDepartment of Material Sciences and Process EngineeringBOKU-University of Natural Resources and Life SciencesMuthgasse 181190ViennaAustria
| | - Vincent J. P. Boerkamp
- Laboratory of Food ChemistryWageningen University & ResearchBornse Weilanden 96708 WGWageningen (TheNetherlands
| | - Gijs van Erven
- Laboratory of Food ChemistryWageningen University & ResearchBornse Weilanden 96708 WGWageningen (TheNetherlands
| | - Roland Ludwig
- Biocatalysis and Biosensing LaboratoryDepartment of Food Science and TechnologyBOKU-University of Natural Resources and Life SciencesMuthgasse 181190ViennaAustria
| | - Willem J. H. van Berkel
- Laboratory of Food ChemistryWageningen University & ResearchBornse Weilanden 96708 WGWageningen (TheNetherlands
| | - Mirjam A. Kabel
- Laboratory of Food ChemistryWageningen University & ResearchBornse Weilanden 96708 WGWageningen (TheNetherlands
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Comparative Secretomics Analysis Reveals the Major Components of Penicillium oxalicum 16 and Trichoderma reesei RUT-C30. Microorganisms 2021; 9:microorganisms9102042. [PMID: 34683363 PMCID: PMC8538001 DOI: 10.3390/microorganisms9102042] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2021] [Revised: 09/16/2021] [Accepted: 09/24/2021] [Indexed: 11/23/2022] Open
Abstract
In this study, the major secretome components of Penicillium oxalicum 16 and Trichoderma reesei RUT-C30 under wheat bran (WB) and rice straw (RS) solid-state fermentation were systematically analyzed. The activities of the major components, e.g., cellulase, hemicellulase, and amylase, were consistent with their abundance in the secretomes. P. oxalicum 16 secreted more abundant glycoside hydrolases than T. reesei RUT-C30. The main up-regulated proteins from the induction of WB, compared with that from RS, were amylase, pectinase, and protease, whereas the main down-regulated enzymes were cellulase, hemicellulase, swollenin, and lytic polysaccharide monooxygenase (LPMO). Specifically, WB induced more β-1,4-glucosidases, namely, S8B0F3 (UniProt ID), and A0A024RWA5 than RS, but RS induced more β-1,4-exoglucanases and β-1,4-endoglucanases, namely, A0A024RXP8, A024SH76, S7B6D6, S7ZP52, A024SH20, A024S2H5, S8BGM3, S7ZX22, and S8AIJ2. The P. oxalicum 16 xylanases S8AH74 and S7ZA57 were the major components responsible for degrading soluble xylan, and S8BDN2 probably acted on solid-state hemicellulose instead of soluble xylan. The main hemicellulase component of T. reesei RUT-C30 in RS was the xyloglucanase A0A024S9Z6 with an abundance of 16%, but T. reesei RUT-C30 lacked the hemicellulase mannanase and had a small amount of the hemicellulase xylanase. P. oxalicum 16 produced more amylase than T. reesei RUT-C30, and the results suggest amylase S7Z6T2 may degrade soluble starch. The percentage of the glucoamylase S8B6D7 did not significantly change, and reached an average abundance of 5.5%. The major auxiliary degradation enzymes of P. oxalicum 16 were LPMOs S7Z716 and S7ZPW1, whereas those of T. reesei RUT-C30 were swollenin and LPMOs A0A024SM10, A0A024SFJ2, and A0A024RZP7.
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Li Y, Yu J, Zhang P, Long T, Mo Y, Li J, Li Q. Comparative transcriptome analysis of Trichoderma reesei reveals different gene regulatory networks induced by synthetic mixtures of glucose and β-disaccharide. BIORESOUR BIOPROCESS 2021; 8:57. [PMID: 38650287 PMCID: PMC10991369 DOI: 10.1186/s40643-021-00411-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Accepted: 06/26/2021] [Indexed: 11/10/2022] Open
Abstract
The mixture of glucose and β-disaccharide (MGD) synthesized by transglycosylation of glucose as a low-cost soluble carbon source can efficiently induce cellulase production in Trichoderma reesei, which holds potential for the biorefining of lignocellulosic biomass. However, it is not yet fully understood how MGD induces T. reesei cellulase. In this study, transcriptomic analyses were conducted to investigate the molecular basis of MGD for lignocellulose-degrading enzyme production of T. reesei Rut C30 compared with that on lactose. Particular attention was paid to CAZymes, transcription factors, transporters and other protein processing pathways related to lignocellulose degradation. As a result, MGD can elicit transcription of GH5-, GH6- and GH7-encoding cellulases that is up to 1.4-fold higher than that induced by lactose, but GH11- and GH74-encoding xylanases are downregulated by 1.7- and 4.4-fold, respectively. Gene expression profiles suggest that the transcription activators xyr1 and vib1 are significantly upregulated and that the mitogen-activated protein kinase pathway is strengthened compared to the case of lactose induction. In addition, hac1-encoding UPR-specific transcription factors are significantly upregulated by MGD, which may be enhanced due to proper folding and processing of nascent proteins. These findings provide a theoretical basis for further understanding the characterization of efficient cellulase production using MGD as an inducer in T. reesei and offer potential strategies for strain improvement.
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Affiliation(s)
- Yonghao Li
- Chongqing Key Laboratory of Industrial Fermentation Microorganism and School of Chemistry and Chemical Engineering, Chongqing University of Science and Technology, Chongqing, 401331, China.
| | - Jingze Yu
- Chongqing Key Laboratory of Industrial Fermentation Microorganism and School of Chemistry and Chemical Engineering, Chongqing University of Science and Technology, Chongqing, 401331, China
| | - Peng Zhang
- Chongqing Key Laboratory of Industrial Fermentation Microorganism and School of Chemistry and Chemical Engineering, Chongqing University of Science and Technology, Chongqing, 401331, China
| | - Tingting Long
- Chongqing Key Laboratory of Industrial Fermentation Microorganism and School of Chemistry and Chemical Engineering, Chongqing University of Science and Technology, Chongqing, 401331, China
| | - Yi Mo
- Chongqing Key Laboratory of Industrial Fermentation Microorganism and School of Chemistry and Chemical Engineering, Chongqing University of Science and Technology, Chongqing, 401331, China
| | - Jianghong Li
- Chongqing Key Laboratory of Industrial Fermentation Microorganism and School of Chemistry and Chemical Engineering, Chongqing University of Science and Technology, Chongqing, 401331, China
| | - Qian Li
- Chongqing Key Laboratory of Industrial Fermentation Microorganism and School of Chemistry and Chemical Engineering, Chongqing University of Science and Technology, Chongqing, 401331, China
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Yamashita M, Tsujikami M, Murata S, Kobayashi T, Shimizu M, Kato M. Artificial AmyR::XlnR transcription factor induces α-amylase production in response to non-edible xylan-containing hemicellulosic biomass. Enzyme Microb Technol 2021; 145:109762. [PMID: 33750542 DOI: 10.1016/j.enzmictec.2021.109762] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Revised: 01/22/2021] [Accepted: 02/04/2021] [Indexed: 12/17/2022]
Abstract
Filamentous fungi belonging to the Aspergillus genus are one of the most favored microorganisms for industrial enzyme production because they can secrete large amounts of proteins into the culture medium. α-Amylase, an enzyme produced by Aspergillus species, is important for food and industrial applications. The production of α-amylase is induced by starch, mainly obtained from the edible biomass; however, the increasing demand for foods is limiting the application of the latter. Therefore, it is expected that using the non-edible biomass, such as rice straw, could improve the competition for industrial application starch containing resources. The transcription factor AmyR activates the transcription of amylolytic enzyme genes, while the transcription factor XlnR activates the transcription of xylanolytic enzyme genes in response to xylose. In this study, we aimed to construct an artificial AmyR::XlnR transcription factor (AXTF) by replacing the DNA-binding domain (1-159 amino acids) of XlnR with that (1-68 aa) of AmyR, which is capable of inducing amylolytic enzyme production in response to xylan-containing hemicellulosic biomass. The chimeric transcription factor AXTF was constructed and expressed using the gapA promoter in the amyR-deficient mutant strain SA1. When the AXTF strain was cultured in the minimal medium containing xylose as the carbon source, the amyB, amyF, agdB, and agdE transcription levels were 41.1-, 11.3-, 37.9-, and 23.7-fold higher, respectively, than those of the wild-type strain. The α-amylase and α-glucosidase activities in the culture supernatant of the AXTF strain grown with xylose for 48 h were 696.6 and 536.1 U/mL, respectively, while these activities were not detected in the culture supernatant of the wild-type and SA1 strains. When rice straw hydrolysate was used as a carbon source, the α-amylase and α-glucosidase activities were 590.2 and 362.7 U/mL, respectively. Thus, we successfully generated an Aspergillus nidulans strain showing amylolytic enzyme production in response to non-edible xylan-containing hemicellulosic biomass by transforming it with the chimeric transcription factor AXTF. Furthermore, the use of genes encoding engineered transcription factors is advantageous because introducing such genes into an industrial Aspergillus strain has similar simultaneous effects on multiple amylase genes controlled by AmyR.
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Affiliation(s)
- Miharu Yamashita
- Faculty of Agriculture, Meijo University, Shiogamaguchi, Tenpaku-ku, Nagoya, Aichi, 468-8502, Japan
| | - Masaya Tsujikami
- Faculty of Agriculture, Meijo University, Shiogamaguchi, Tenpaku-ku, Nagoya, Aichi, 468-8502, Japan
| | - Shunsuke Murata
- Faculty of Agriculture, Meijo University, Shiogamaguchi, Tenpaku-ku, Nagoya, Aichi, 468-8502, Japan
| | - Tetsuo Kobayashi
- Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Aichi 464-8601, Japan
| | - Motoyuki Shimizu
- Faculty of Agriculture, Meijo University, Shiogamaguchi, Tenpaku-ku, Nagoya, Aichi, 468-8502, Japan
| | - Masashi Kato
- Faculty of Agriculture, Meijo University, Shiogamaguchi, Tenpaku-ku, Nagoya, Aichi, 468-8502, Japan.
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Advanced Bioethanol Production: From Novel Raw Materials to Integrated Biorefineries. Processes (Basel) 2021. [DOI: 10.3390/pr9020206] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The production of so-called advanced bioethanol offers several advantages compared to traditional bioethanol production processes in terms of sustainability criteria. This includes, for instance, the use of nonfood crops or residual biomass as raw material and a higher potential for reducing greenhouse gas emissions. The present review focuses on the recent progress related to the production of advanced bioethanol, (i) highlighting current results from using novel biomass sources such as the organic fraction of municipal solid waste and certain industrial residues (e.g., residues from the paper, food, and beverage industries); (ii) describing new developments in pretreatment technologies for the fractionation and conversion of lignocellulosic biomass, such as the bioextrusion process or the use of novel ionic liquids; (iii) listing the use of new enzyme catalysts and microbial strains during saccharification and fermentation processes. Furthermore, the most promising biorefinery approaches that will contribute to the cost-competitiveness of advanced bioethanol production processes are also discussed, focusing on innovative technologies and applications that can contribute to achieve a more sustainable and effective utilization of all biomass fractions. Special attention is given to integrated strategies such as lignocellulose-based biorefineries for the simultaneous production of bioethanol and other high added value bioproducts.
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Abdel-Azeem AM, Abu-Elsaoud AM, Abo Nahas HH, Abdel-Azeem MA, Balbool BA, Mousa MK, Ali NH, Darwish AMG. Biodiversity and Industrial Applications of Genus Chaetomium. Fungal Biol 2021. [DOI: 10.1007/978-3-030-67561-5_5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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10
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Guo X, An Y, Chai C, Sang J, Jiang L, Lu F, Dai Y, Liu F. Construction of the R17L mutant of MtC1LPMO for improved lignocellulosic biomass conversion by rational point mutation and investigation of the mechanism by molecular dynamics simulations. BIORESOURCE TECHNOLOGY 2020; 317:124024. [PMID: 32836036 DOI: 10.1016/j.biortech.2020.124024] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 08/12/2020] [Accepted: 08/13/2020] [Indexed: 06/11/2023]
Abstract
To enhance the biomass conversion efficiency, the R17L mutant of the lytic polysaccharide monooxygenase (LPMO) MtC1LPMO with improved catalytic efficiency was constructed via rational point mutation based on the HotSpot Wizard 3.0 and dezyme web servers. Compared with the wild-type (WT) MtC1LPMO, R17L exhibited a 1.8-fold increase of specific activity and 1.92-fold increase of catalytic efficiency (kcat/Km). The degree of increase of the reducing sugar yield from microcrystalline cellulose and three plant biomass materials during synergistic hydrolysis using cellulase in combination with R17L was about 2 times higher than with the WT. Molecular dynamics simulations revealed that the R17L mutation reduced the stability of the region R18-I36, which then weakened the direct interactions between region N24-V31 and the substrate cellohexaose. Consequently, the deflection time of the cellohexaose conformation in R17L was prolonged compared to the WT, which enhanced its catalytic efficiency.
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Affiliation(s)
- Xiao Guo
- Key Laboratory of Industrial Fermentation Microbiology of the Ministry of Education, Tianjin 300457, PR China; Tianjin Key Laboratory of Industrial Microbiology, Tianjin 300457, PR China; College of Biotechnology, Tianjin University of Science & Technology, Tianjin 300457, PR China
| | - Yajing An
- Key Laboratory of Industrial Fermentation Microbiology of the Ministry of Education, Tianjin 300457, PR China; Tianjin Key Laboratory of Industrial Microbiology, Tianjin 300457, PR China; College of Biotechnology, Tianjin University of Science & Technology, Tianjin 300457, PR China
| | - Chengcheng Chai
- Key Laboratory of Industrial Fermentation Microbiology of the Ministry of Education, Tianjin 300457, PR China; Tianjin Key Laboratory of Industrial Microbiology, Tianjin 300457, PR China; College of Biotechnology, Tianjin University of Science & Technology, Tianjin 300457, PR China
| | - Jingcheng Sang
- Key Laboratory of Industrial Fermentation Microbiology of the Ministry of Education, Tianjin 300457, PR China; Tianjin Key Laboratory of Industrial Microbiology, Tianjin 300457, PR China; College of Biotechnology, Tianjin University of Science & Technology, Tianjin 300457, PR China
| | - Luying Jiang
- Key Laboratory of Industrial Fermentation Microbiology of the Ministry of Education, Tianjin 300457, PR China; Tianjin Key Laboratory of Industrial Microbiology, Tianjin 300457, PR China; College of Biotechnology, Tianjin University of Science & Technology, Tianjin 300457, PR China
| | - Fuping Lu
- Key Laboratory of Industrial Fermentation Microbiology of the Ministry of Education, Tianjin 300457, PR China; Tianjin Key Laboratory of Industrial Microbiology, Tianjin 300457, PR China; College of Biotechnology, Tianjin University of Science & Technology, Tianjin 300457, PR China
| | - Yujie Dai
- Key Laboratory of Industrial Fermentation Microbiology of the Ministry of Education, Tianjin 300457, PR China; Tianjin Key Laboratory of Industrial Microbiology, Tianjin 300457, PR China; College of Biotechnology, Tianjin University of Science & Technology, Tianjin 300457, PR China
| | - Fufeng Liu
- Key Laboratory of Industrial Fermentation Microbiology of the Ministry of Education, Tianjin 300457, PR China; Tianjin Key Laboratory of Industrial Microbiology, Tianjin 300457, PR China; College of Biotechnology, Tianjin University of Science & Technology, Tianjin 300457, PR China.
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Zhou X, Xu Z, He J, Li Y, Pan C, Wang C, Deng MR, Zhu H. A myxobacterial LPMO10 has oxidizing cellulose activity for promoting biomass enzymatic saccharification of agricultural crop straws. BIORESOURCE TECHNOLOGY 2020; 318:124217. [PMID: 33096440 DOI: 10.1016/j.biortech.2020.124217] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 09/29/2020] [Accepted: 09/30/2020] [Indexed: 06/11/2023]
Abstract
Myxobacteria are soil microorganisms with the ability to break down biological macromolecules due to the secretion of a large number of extracellular enzymes, but there has been no research report on myxobacterial lytic polysaccharide monooxygenases (LPMOs). In this study, two LPMO10s, ViLPMO10A and ViLPMO10B, from myxobacterium Vitiosangium sp. GDMCC 1.1324 were characterized. Of which, ViLPMO10B is a C1-oxidizing cellulose-active LPMO. Moreover, ViLPMO10B could decrease the degree of polymerization of crop straws cellulose and synergize with commercial cellulase to promote the saccharification. When the weight ratio of commercial cellulase to ViLPMO10B was 9:1, the conversion efficiency of corn stalk, sugarcane bagasse, and rice straw into reducing sugar was improved by 17%, 16%, and 22%, respectively, compared with commercial cellulase without ViLPMO10B. These results indicate that ViLPMO10B has the potential to be a component of a high-efficient cellulase cocktail and has application value in the saccharification of agricultural residual biomasses.
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Affiliation(s)
- Xiaoli Zhou
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Microbial Culture Collection Center (GDMCC), Guangdong Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, China
| | - Zhiqiang Xu
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Microbial Culture Collection Center (GDMCC), Guangdong Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, China
| | - Jia He
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Microbial Culture Collection Center (GDMCC), Guangdong Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, China
| | - Yueqiu Li
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Microbial Culture Collection Center (GDMCC), Guangdong Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, China
| | - Chengxiang Pan
- College of Horticulture, South China Agricultural University, Guangzhou 510642, China
| | - Chunling Wang
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Microbial Culture Collection Center (GDMCC), Guangdong Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, China
| | - Ming-Rong Deng
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Microbial Culture Collection Center (GDMCC), Guangdong Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, China
| | - Honghui Zhu
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Microbial Culture Collection Center (GDMCC), Guangdong Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, China.
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12
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Bunterngsook B, Mhuantong W, Kanokratana P, Iseki Y, Watanabe T, Champreda V. Identification and characterization of a novel AA9-type lytic polysaccharide monooxygenase from a bagasse metagenome. Appl Microbiol Biotechnol 2020; 105:197-210. [PMID: 33230603 DOI: 10.1007/s00253-020-11002-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Revised: 10/20/2020] [Accepted: 11/03/2020] [Indexed: 11/25/2022]
Abstract
Lytic polysaccharide monooxygenases (LPMOs) are auxiliary enzymes catalyzing oxidative cleavages of cellulose chains in crystalline regions, resulting in their increasing accessibility to the hydrolytic enzyme counterparts and hence higher released sugars from biomass saccharification. In this study, a novel auxiliary protein family 9 LPMO (BgAA9) was identified from a metagenomic library derived from a thermophilic microbial community in bagasse collection site where diverse AA9 and AA10 putative sequences were annotated. The enzyme showed highest similarity to a glycoside hydrolase family 61 from Chaetomium thermophilum. Recombinant BgAA9 expressed in Pichia pastoris cleaved cellohexaose (DP6) into shorter cellooligosaccharides (DP2, DP3, and DP4). Supplementation BgAA9 to a commercial cellulase, Accellerase® 1500 showed strong synergistic effect on saccharification of Avicel® PH101, decrystallized cellulose, filter paper, and alkaline-pretreated sugarcane bagasse, resulting in 63-93% increase in the total reducing sugar yield after incubation at 50 °C for 72 h. Strong synergism was shown between BgAA9 and the cellulase with the highest total fermentable sugar yield obtained from 75:25% of Accellerase®1500:BgAA9 which released 39 mg glucose/FPU (filter paper unit) equivalent to 38.7% higher than Accellerase®1500 alone at the same total protein dosage of 5 mg/g substrate according to the mixture design study. The enzyme represented the first characterized LPMO from environmental metagenome and a potent auxiliary component for biomass saccharification. KEY POINTS: • BgAA9 represents the first characterized LPMO from metagenome. • 12 AA families were annotated in thermophilic bagasse fosmid library by NGS. • BgAA9 showed homology to Cel61 in Chaetomium thermophilum. • BgAA9 oxidized cellohexaose and PASC to DP2, DP4, and DP6. • BgAA9 showed strong synergism to Accellerase on bagasse hydrolysis.
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Affiliation(s)
- Benjarat Bunterngsook
- Enzyme Technology Laboratory, Biorefinery and Bioproduct Technology Research Group, National Center for Genetic Engineering and Biotechnology, 113 Thailand Science Park, Phahonyothin Road, Khlong Luang, Pathumthani, 12120, Thailand
| | - Wuttichai Mhuantong
- Enzyme Technology Laboratory, Biorefinery and Bioproduct Technology Research Group, National Center for Genetic Engineering and Biotechnology, 113 Thailand Science Park, Phahonyothin Road, Khlong Luang, Pathumthani, 12120, Thailand
| | - Pattanop Kanokratana
- Enzyme Technology Laboratory, Biorefinery and Bioproduct Technology Research Group, National Center for Genetic Engineering and Biotechnology, 113 Thailand Science Park, Phahonyothin Road, Khlong Luang, Pathumthani, 12120, Thailand
| | - Yu Iseki
- Laboratory of Biomass Conversion, Research Institute for Sustainable Humanosphere (RISH), Kyoto University, Gokasho, Uji, Kyoto, 611-0011, Japan
| | - Takashi Watanabe
- Laboratory of Biomass Conversion, Research Institute for Sustainable Humanosphere (RISH), Kyoto University, Gokasho, Uji, Kyoto, 611-0011, Japan
| | - Verawat Champreda
- Enzyme Technology Laboratory, Biorefinery and Bioproduct Technology Research Group, National Center for Genetic Engineering and Biotechnology, 113 Thailand Science Park, Phahonyothin Road, Khlong Luang, Pathumthani, 12120, Thailand.
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13
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Comparative Genomic Analysis of Dactylonectria torresensis Strains from Grapevine, Soil and Weed Highlights Potential Mechanisms in Pathogenicity and Endophytic Lifestyle. J Fungi (Basel) 2020; 6:jof6040255. [PMID: 33138048 PMCID: PMC7712071 DOI: 10.3390/jof6040255] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 10/26/2020] [Accepted: 10/27/2020] [Indexed: 01/19/2023] Open
Abstract
The soil-borne fungus Dactylonectria torresensis is the most common causal agent of black-foot disease in Europe. However, there is a lack of understanding on how this fungus can provoke plant symptoms. In this study, we sequenced, annotated and analyzed the genomes of three isolates of D. torresensis collected from asymptomatic vine, weed and soil. Sequenced genomes were further compared to those of 27 fungal species including root and aerial pathogens, white rot degraders, indoor biodeterioration agents, saprotrophs, dark septate endophytes and mycorrhiza. Strains of D. torresensis present genomes with between 64 and 65 Mbp and with up to 18,548 predicted genes for each strain. Average Nucleotide Identity (ANI) shows that strains are different according to genome contents. Clusters of orthologous groups were compared, and clusters of genes related to necroses were particularly detected in all strains of D. torresensis (necrosis inducing peptides and proteins, and ethylene inducing peptides) as well as several genes involved in resistance against fungicides frequently used in viticulture such as copper. Interestingly, an expanded high number of genes related to carbohydrate-active enzymes were detected in each Dactylonectria strain, especially those related to glycoside hydrolases that could be involved in penetration of plant tissues or pathogenicity. An increased number of candidate genes for CAZyme classes AA9 and AA3-1 supports the ability of strains to efficiently degrade plant material. High numbers of genes of D. torresensis related to secretome and small secreted proteins were further characterized. Moreover, the presence of several gene clusters such as fujikurin-like genes was detected and were normally found in Fusariumfujikuroi, that have been linked to fungal pathogenicity. The phenotypes of the three strains investigated showed further difference in light response. We found that Dactylonectria strains have an increased number of photoreceptor encoding genes and we showed sequence alterations. Altogether, the results highlight several gene clusters present in D. torresensis strains that could be linked to endophytic lifestyle, pathogenicity, plant maceration and degradation of plant tissues as well as adaptation to soil contaminated with metals and metalloids and light response.
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Limsakul P, Phitsuwan P, Waeonukul R, Pason P, Tachaapaikoon C, Poomputsa K, Kosugi A, Sakka M, Sakka K, Ratanakhanokchai K. A novel AA10 from Paenibacillus curdlanolyticus and its synergistic action on crystalline and complex polysaccharides. Appl Microbiol Biotechnol 2020; 104:7533-7550. [PMID: 32651597 DOI: 10.1007/s00253-020-10758-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 06/18/2020] [Accepted: 06/24/2020] [Indexed: 02/08/2023]
Abstract
Lytic polysaccharide monooxygenases (LPMOs) play an important role in the degradation of complex polysaccharides in lignocellulosic biomass. In the present study, we characterized a modular LPMO (PcAA10A), consisting of a family 10 auxiliary activity of LPMO (AA10) catalytic domain, and non-catalytic domains including a family 5 carbohydrate-binding module, two fibronectin type-3 domains, and a family 3 carbohydrate-binding module from Paenibacillus curdlanolyticus B-6, which was expressed in a recombinant Escherichia coli. Comparison of activities between full-length PcAA10A and the catalytic domain polypeptide (PcAA10A_CD) indicates that the non-catalytic domains are important for the deconstruction of crystalline cellulose and complex polysaccharides contained in untreated lignocellulosic biomass. Interestingly, PcAA10A_CD acted not only on cellulose and chitin, but also on xylan, mannan, and xylan and cellulose contained in lignocellulosic biomass, which has not been reported for the AA10 family. Mutation of the key residues, Trp51 located at subsite - 2 and Phe171 located at subsite +2, in the substrate-binding site of PcAA10A_CD revealed that these residues are substantially involved in broad substrate specificity toward cellulose, xylan, and mannan, albeit with a low effect toward chitin. Furthermore, PcAA10A had a boosting effect on untreated corn hull degradation by P. curdlanolyticus B-6 endo-xylanase Xyn10D and Clostridium thermocellum endo-glucanase Cel9A. These results suggest that PcAA10A is a unique LPMO capable of cleaving and enhancing lignocellulosic biomass degradation, making it a good candidate for biotechnological applications. KEY POINTS: • PcAA10A is a novel modular LPMO family 10 from Paenibacillus curdlanolyticus. • PcAA10A showed broad substrate specificity on β-1,4 glycosidic linkage substrates. • Non-catalytic domains are important for degrading complex polysaccharides. • PcAA10A is a unique LPMO capable of enhancing lignocellulosic biomass degradation.
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Affiliation(s)
- Puangpen Limsakul
- School of Bioresources and Technology, King Mongkut's University of Technology Thonburi, Bangkok, 10150, Thailand
| | - Paripok Phitsuwan
- School of Bioresources and Technology, King Mongkut's University of Technology Thonburi, Bangkok, 10150, Thailand
| | - Rattiya Waeonukul
- Pilot Plant Development and Training Institute, King Mongkut's University of Technology Thonburi, Bangkok, 10150, Thailand
| | - Patthra Pason
- Pilot Plant Development and Training Institute, King Mongkut's University of Technology Thonburi, Bangkok, 10150, Thailand
| | - Chakrit Tachaapaikoon
- Pilot Plant Development and Training Institute, King Mongkut's University of Technology Thonburi, Bangkok, 10150, Thailand
| | - Kanokwan Poomputsa
- School of Bioresources and Technology, King Mongkut's University of Technology Thonburi, Bangkok, 10150, Thailand
| | - Akihiko Kosugi
- Biological Resources and Post-harvest Division, Japan International Research Center for Agricultural Sciences, Tsukuba, Ibaraki, 305-8686, Japan
| | - Makiko Sakka
- Graduated School of Bioresources, Mie University, Tsu, Mie, 514-8507, Japan
| | - Kazuo Sakka
- Graduated School of Bioresources, Mie University, Tsu, Mie, 514-8507, Japan.
| | - Khanok Ratanakhanokchai
- School of Bioresources and Technology, King Mongkut's University of Technology Thonburi, Bangkok, 10150, Thailand.
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15
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Zhang R. Functional characterization of cellulose-degrading AA9 lytic polysaccharide monooxygenases and their potential exploitation. Appl Microbiol Biotechnol 2020; 104:3229-3243. [PMID: 32076777 DOI: 10.1007/s00253-020-10467-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2019] [Revised: 12/25/2019] [Accepted: 02/12/2020] [Indexed: 01/05/2023]
Abstract
Cellulose-degrading auxiliary activity family 9 (AA9) lytic polysaccharide monooxygenases (LPMOs) are known to be widely distributed among filamentous fungi and participate in the degradation of lignocellulose via the oxidative cleavage of celluloses, cello-oligosaccharides, or hemicelluloses. AA9 LPMOs have been reported to have extensive interactions with not only cellulases but also oxidases. The addition of AA9 LPMOs can greatly reduce the amount of cellulase needed for saccharification and increase the yield of glucose. The discovery of AA9 LPMOs has greatly changed our understanding of how fungi degrade cellulose. In this review, apart from summarizing the recent discoveries related to their catalytic reaction, functional diversity, and practical applications, the stability, expression system, and protein engineering of AA9 LPMOs are reviewed for the first time. This review may provide a reference value to further broaden the substrate range of AA9 LPMOs, expand the scope of their practical applications, and realize their customization for industrial utilization.Key Points• The stability and expression system of AA9 LPMOs are reviewed for the first time.• The protein engineering of AA9 LPMOs is systematically summarized for the first time.• The latest research results on the catalytic mechanism of AA9 LPMOs are summarized.• The application of AA9 LPMOs and their relationship with other enzymes are reviewed.
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Affiliation(s)
- Ruiqin Zhang
- State Key Laboratory of Microbial Technology, Shandong University, No. 72 Binhai Road, Qingdao, 266237, China.
- Department of Bioengineering, Huainan Normal University, No. 278 Xueyuannan Road, Huainan, 232038, China.
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16
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Darwish AMG, Abdel-Azeem AM. Chaetomium Enzymes and Their Applications. Fungal Biol 2020. [DOI: 10.1007/978-3-030-31612-9_9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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17
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Zhou X, Qi X, Huang H, Zhu H. Sequence and Structural Analysis of AA9 and AA10 LPMOs: An Insight into the Basis of Substrate Specificity and Regioselectivity. Int J Mol Sci 2019; 20:ijms20184594. [PMID: 31533304 PMCID: PMC6771041 DOI: 10.3390/ijms20184594] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Revised: 09/03/2019] [Accepted: 09/13/2019] [Indexed: 12/23/2022] Open
Abstract
Lytic polysaccharide monooxygenases (LPMOs) are key enzymes in both the natural carbon cycle and the biorefinery industry. Understanding the molecular basis of LPMOs acting on polysaccharide substrates is helpful for improving industrial cellulase cocktails. Here we analyzed the sequences, structures, and substrate binding modes of LPMOs to uncover the factors that influence substrate specificity and regioselectivity. Our results showed that the different compositions of a motif located on L2 affect the electrostatic potentials of substrate binding surfaces, which in turn affect substrate specificities of AA10 LPMOs. A conserved Asn at a distance of 7 Å from the active center Cu might, together with the conserved Ser immediately before the second catalytic His, determine the localization of LPMOs on substrate, and thus contribute to C4-oxidizing regioselectivity. The findings in this work provide an insight into the molecular basis of substrate specificity and regioselectivity of LPMOs.
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Affiliation(s)
- Xiaoli Zhou
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Microbial Culture Collection Center (GDMCC), Guangdong Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, China.
| | - Xiaohua Qi
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Microbial Culture Collection Center (GDMCC), Guangdong Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, China.
| | - Hongxia Huang
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Microbial Culture Collection Center (GDMCC), Guangdong Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, China.
| | - Honghui Zhu
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Microbial Culture Collection Center (GDMCC), Guangdong Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, China.
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18
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Champreda V, Mhuantong W, Lekakarn H, Bunterngsook B, Kanokratana P, Zhao XQ, Zhang F, Inoue H, Fujii T, Eurwilaichitr L. Designing cellulolytic enzyme systems for biorefinery: From nature to application. J Biosci Bioeng 2019; 128:637-654. [PMID: 31204199 DOI: 10.1016/j.jbiosc.2019.05.007] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Revised: 05/06/2019] [Accepted: 05/11/2019] [Indexed: 12/14/2022]
Abstract
Cellulolytic enzymes play a key role on conversion of lignocellulosic plant biomass to biofuels and biochemicals in sugar platform biorefineries. In this review, we survey composite carbohydrate-active enzymes (CAZymes) among groups of cellulolytic fungi and bacteria that exist under aerobic and anaerobic conditions. Recent advances in designing effective cellulase mixtures are described, starting from the most complex microbial consortium-based enzyme preparations, to single-origin enzymes derived from intensively studied cellulase producers such as Trichoderma reesei, Talaromyces cellulolyticus, and Penicellium funiculosum, and the simplest minimal enzyme systems comprising selected sets of mono-component enzymes tailor-made for specific lignocellulosic substrates. We provide a comprehensive update on studies in developing high-performance cellulases for biorefineries.
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Affiliation(s)
- Verawat Champreda
- National Center for Genetic Engineering and Biotechnology, 113 Thailand Science Park, Phahonyothin Road, Khlong Luang, Pathumthani 12120, Thailand.
| | - Wuttichai Mhuantong
- National Center for Genetic Engineering and Biotechnology, 113 Thailand Science Park, Phahonyothin Road, Khlong Luang, Pathumthani 12120, Thailand
| | - Hataikarn Lekakarn
- Department of Biotechnology, Faculty of Science and Technology, Thammasat University, Rangsit Campus, Phahonyothin Road, Khlong Luang, Pathumthani 12120, Thailand
| | - Benjarat Bunterngsook
- National Center for Genetic Engineering and Biotechnology, 113 Thailand Science Park, Phahonyothin Road, Khlong Luang, Pathumthani 12120, Thailand
| | - Pattanop Kanokratana
- National Center for Genetic Engineering and Biotechnology, 113 Thailand Science Park, Phahonyothin Road, Khlong Luang, Pathumthani 12120, Thailand
| | - Xin-Qing Zhao
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Fei Zhang
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Hiroyuki Inoue
- Research Institute for Sustainable Chemistry, National Institute of Advanced Industrial Science and Technology, 3-11-32 Kagamiyama, Hiroshima 739-0046, Japan
| | - Tatsuya Fujii
- Research Institute for Sustainable Chemistry, National Institute of Advanced Industrial Science and Technology, 3-11-32 Kagamiyama, Hiroshima 739-0046, Japan
| | - Lily Eurwilaichitr
- National Center for Genetic Engineering and Biotechnology, 113 Thailand Science Park, Phahonyothin Road, Khlong Luang, Pathumthani 12120, Thailand
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19
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Corrêa TLR, Júnior AT, Wolf LD, Buckeridge MS, dos Santos LV, Murakami MT. An actinobacteria lytic polysaccharide monooxygenase acts on both cellulose and xylan to boost biomass saccharification. BIOTECHNOLOGY FOR BIOFUELS 2019; 12:117. [PMID: 31168322 PMCID: PMC6509861 DOI: 10.1186/s13068-019-1449-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Accepted: 04/22/2019] [Indexed: 05/06/2023]
Abstract
BACKGROUND Lytic polysaccharide monooxygenases (LPMOs) opened a new horizon for biomass deconstruction. They use a redox mechanism not yet fully understood and the range of substrates initially envisaged to be the crystalline polysaccharides is steadily expanding to non-crystalline ones. RESULTS The enzyme KpLPMO10A from the actinomycete Kitasatospora papulosa was cloned and overexpressed in Escherichia coli cells in the functional form with native N-terminal. The enzyme can release oxidized species from chitin (C1-type oxidation) and cellulose (C1/C4-type oxidation) similarly to other AA10 members from clade II (subclade A). Interestingly, KpLPMO10A also cleaves isolated xylan (not complexed with cellulose, C4-type oxidation), a rare activity among LPMOs not described yet for the AA10 family. The synergistic effect of KpLPMO10A with Celluclast® and an endo-β-1,4-xylanase also supports this finding. The crystallographic elucidation of KpLPMO10A at 1.6 Å resolution along with extensive structural analyses did not indicate any evident difference with other characterized AA10 LPMOs at the catalytic interface, tempting us to suggest that these enzymes might also be active on xylan or that the ability to attack both crystalline and non-crystalline substrates involves yet obscure mechanisms of substrate recognition and binding. CONCLUSIONS This work expands the spectrum of substrates recognized by AA10 family, opening a new perspective for the understanding of the synergistic effect of these enzymes with canonical glycoside hydrolases to deconstruct ligno(hemi)cellulosic biomass.
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Affiliation(s)
- Thamy Lívia Ribeiro Corrêa
- Brazilian Bioethanol Science and Technology Laboratory (CTBE), Brazilian Center for Research in Energy and Materials (CNPEM), Campinas, SP Brazil
| | - Atílio Tomazini Júnior
- Brazilian Bioethanol Science and Technology Laboratory (CTBE), Brazilian Center for Research in Energy and Materials (CNPEM), Campinas, SP Brazil
| | - Lúcia Daniela Wolf
- Brazilian Bioethanol Science and Technology Laboratory (CTBE), Brazilian Center for Research in Energy and Materials (CNPEM), Campinas, SP Brazil
| | | | - Leandro Vieira dos Santos
- Brazilian Bioethanol Science and Technology Laboratory (CTBE), Brazilian Center for Research in Energy and Materials (CNPEM), Campinas, SP Brazil
| | - Mario Tyago Murakami
- Brazilian Bioethanol Science and Technology Laboratory (CTBE), Brazilian Center for Research in Energy and Materials (CNPEM), Campinas, SP Brazil
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20
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Zhang F, Bunterngsook B, Li JX, Zhao XQ, Champreda V, Liu CG, Bai FW. Regulation and production of lignocellulolytic enzymes from Trichoderma reesei for biofuels production. ADVANCES IN BIOENERGY 2019. [DOI: 10.1016/bs.aibe.2019.03.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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21
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Loose JSM, Arntzen MØ, Bissaro B, Ludwig R, Eijsink VGH, Vaaje-Kolstad G. Multipoint Precision Binding of Substrate Protects Lytic Polysaccharide Monooxygenases from Self-Destructive Off-Pathway Processes. Biochemistry 2018; 57:4114-4124. [DOI: 10.1021/acs.biochem.8b00484] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jennifer S. M. Loose
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), 1432 Ås, Norway
| | - Magnus Ø. Arntzen
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), 1432 Ås, Norway
| | - Bastien Bissaro
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), 1432 Ås, Norway
| | - Roland Ludwig
- BOKU-University of Natural Resources and Life Sciences, Department of Food Science and Technology, Biocatalysis and Biosensing Laboratory, 1180 Vienna, Austria
| | - Vincent G. H. Eijsink
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), 1432 Ås, Norway
| | - Gustav Vaaje-Kolstad
- Faculty of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences (NMBU), 1432 Ås, Norway
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22
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The effect of a lytic polysaccharide monooxygenase and a xylanase from Gloeophyllum trabeum on the enzymatic hydrolysis of lignocellulosic residues using a commercial cellulase. Enzyme Microb Technol 2018; 113:75-82. [DOI: 10.1016/j.enzmictec.2017.11.007] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Revised: 11/20/2017] [Accepted: 11/21/2017] [Indexed: 12/16/2022]
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23
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Hangasky JA, Iavarone AT, Marletta MA. Reactivity of O 2 versus H 2O 2 with polysaccharide monooxygenases. Proc Natl Acad Sci U S A 2018; 115:4915-4920. [PMID: 29686097 PMCID: PMC5949000 DOI: 10.1073/pnas.1801153115] [Citation(s) in RCA: 130] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Enzymatic conversion of polysaccharides into lower-molecular-weight, soluble oligosaccharides is dependent on the action of hydrolytic and oxidative enzymes. Polysaccharide monooxygenases (PMOs) use an oxidative mechanism to break the glycosidic bond of polymeric carbohydrates, thereby disrupting the crystalline packing and creating new chain ends for hydrolases to depolymerize and degrade recalcitrant polysaccharides. PMOs contain a mononuclear Cu(II) center that is directly involved in C-H bond hydroxylation. Molecular oxygen was the accepted cosubstrate utilized by this family of enzymes until a recent report indicated reactivity was dependent on H2O2 Reported here is a detailed analysis of PMO reactivity with H2O2 and O2, in conjunction with high-resolution MS measurements. The cosubstrate utilized by the enzyme is dependent on the assay conditions. PMOs will directly reduce O2 in the coupled hydroxylation of substrate (monooxygenase activity) and will also utilize H2O2 (peroxygenase activity) produced from the uncoupled reduction of O2 Both cosubstrates require Cu reduction to Cu(I), but the reaction with H2O2 leads to nonspecific oxidation of the polysaccharide that is consistent with the generation of a hydroxyl radical-based mechanism in Fenton-like chemistry, while the O2 reaction leads to regioselective substrate oxidation using an enzyme-bound Cu/O2 reactive intermediate. Moreover, H2O2 does not influence the ability of secretome from Neurospora crassa to degrade Avicel, providing evidence that molecular oxygen is a physiologically relevant cosubstrate for PMOs.
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Affiliation(s)
- John A Hangasky
- California Institute for Quantitative Biosciences, University of California, Berkeley, CA 94720
| | - Anthony T Iavarone
- California Institute for Quantitative Biosciences, University of California, Berkeley, CA 94720
- Department of Chemistry, University of California, Berkeley, CA 94720
| | - Michael A Marletta
- California Institute for Quantitative Biosciences, University of California, Berkeley, CA 94720;
- Department of Chemistry, University of California, Berkeley, CA 94720
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720
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Structural and electronic determinants of lytic polysaccharide monooxygenase reactivity on polysaccharide substrates. Nat Commun 2017; 8:1064. [PMID: 29057953 PMCID: PMC5651836 DOI: 10.1038/s41467-017-01247-3] [Citation(s) in RCA: 117] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2017] [Accepted: 08/29/2017] [Indexed: 02/02/2023] Open
Abstract
Lytic polysaccharide monooxygenases (LPMOs) are industrially important copper-dependent enzymes that oxidatively cleave polysaccharides. Here we present a functional and structural characterization of two closely related AA9-family LPMOs from Lentinus similis (LsAA9A) and Collariella virescens (CvAA9A). LsAA9A and CvAA9A cleave a range of polysaccharides, including cellulose, xyloglucan, mixed-linkage glucan and glucomannan. LsAA9A additionally cleaves isolated xylan substrates. The structures of CvAA9A and of LsAA9A bound to cellulosic and non-cellulosic oligosaccharides provide insight into the molecular determinants of their specificity. Spectroscopic measurements reveal differences in copper co-ordination upon the binding of xylan and glucans. LsAA9A activity is less sensitive to the reducing agent potential when cleaving xylan, suggesting that distinct catalytic mechanisms exist for xylan and glucan cleavage. Overall, these data show that AA9 LPMOs can display different apparent substrate specificities dependent upon both productive protein-carbohydrate interactions across a binding surface and also electronic considerations at the copper active site.
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Physiological and Molecular Understanding of Bacterial Polysaccharide Monooxygenases. Microbiol Mol Biol Rev 2017; 81:81/3/e00015-17. [PMID: 28659491 DOI: 10.1128/mmbr.00015-17] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Bacteria have long been known to secrete enzymes that degrade cellulose and chitin. The degradation of these two polymers predominantly involves two enzyme families that work synergistically with one another: glycoside hydrolases (GHs) and polysaccharide monooxygenases (PMOs). Although bacterial PMOs are a relatively recent addition to the known biopolymer degradation machinery, there is an extensive amount of literature implicating PMO in numerous physiological roles. This review focuses on these diverse and physiological aspects of bacterial PMOs, including facilitating endosymbiosis, conferring a nutritional advantage, and enhancing virulence in pathogenic organisms. We also discuss the correlation between the presence of PMOs and bacterial lifestyle and speculate on the advantages conferred by PMOs under these conditions. In addition, the molecular aspects of bacterial PMOs, as well as the mechanisms regulating PMO expression and the function of additional domains associated with PMOs, are described. We anticipate that increasing research efforts in this field will continue to expand our understanding of the molecular and physiological roles of bacterial PMOs.
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Pimentel AC, Ematsu GC, Liberato MV, Paixão DA, Franco Cairo JPL, Mandelli F, Tramontina R, Gandin CA, de Oliveira Neto M, Squina FM, Alvarez TM. Biochemical and biophysical properties of a metagenome-derived GH5 endoglucanase displaying an unconventional domain architecture. Int J Biol Macromol 2017; 99:384-393. [DOI: 10.1016/j.ijbiomac.2017.02.075] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Revised: 02/05/2017] [Accepted: 02/06/2017] [Indexed: 11/15/2022]
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27
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Ma S, Preims M, Piumi F, Kappel L, Seiboth B, Record E, Kracher D, Ludwig R. Molecular and catalytic properties of fungal extracellular cellobiose dehydrogenase produced in prokaryotic and eukaryotic expression systems. Microb Cell Fact 2017; 16:37. [PMID: 28245812 PMCID: PMC5331742 DOI: 10.1186/s12934-017-0653-5] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Accepted: 02/25/2017] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Cellobiose dehydrogenase (CDH) is an extracellular enzyme produced by lignocellulolytic fungi. cdh gene expression is high in cellulose containing media, but relatively low CDH concentrations are found in the supernatant of fungal cultures due to strong binding to cellulose. Therefore, heterologous expression of CDH in Pichia pastoris was employed in the last 15 years, but the obtained enzymes were over glycosylated and had a reduced specific activity. RESULTS We compare the well-established CDH expression host P. pastoris with the less frequently used hosts Escherichia coli, Aspergillus niger, and Trichoderma reesei. The study evaluates the produced quantity and protein homogeneity of Corynascus thermophilus CDH in the culture supernatants, the purification, and finally compares the enzymes in regard to cofactor loading, glycosylation, catalytic constants and thermostability. CONCLUSIONS Whereas E. coli could only express the catalytic dehydrogenase domain of CDH, all eukaryotic hosts could express full length CDH including the cytochrome domain. The CDH produced by T. reesei was most similar to the CDH originally isolated from the fungus C. thermophilus in regard to glycosylation, cofactor loading and catalytic constants. Under the tested experimental conditions the fungal expression hosts produce CDH of superior quality and uniformity compared to P. pastoris.
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Affiliation(s)
- Su Ma
- Department of Food Sciences and Technology, Vienna Institute of Biotechnology, BOKU-University of Natural Resources and Life Sciences, Vienna, Austria
| | - Marita Preims
- Department of Food Sciences and Technology, Vienna Institute of Biotechnology, BOKU-University of Natural Resources and Life Sciences, Vienna, Austria
| | - François Piumi
- UMR BDR, INRA, ENVA, Université Paris Saclay, 78350, Jouy en Josas, France
| | - Lisa Kappel
- Research Area Biochemical Technology, Institute of Chemical Engineering, TU Wien, Gumpendorferstrasse 1a, Vienna, Austria
| | - Bernhard Seiboth
- Research Area Biochemical Technology, Institute of Chemical Engineering, TU Wien, Gumpendorferstrasse 1a, Vienna, Austria
| | - Eric Record
- Aix Marseille Université, INRA, BBF (Biodiversité et Biotechnologie Fongiques), Marseille, France
| | - Daniel Kracher
- Department of Food Sciences and Technology, Vienna Institute of Biotechnology, BOKU-University of Natural Resources and Life Sciences, Vienna, Austria
| | - Roland Ludwig
- Department of Food Sciences and Technology, Vienna Institute of Biotechnology, BOKU-University of Natural Resources and Life Sciences, Vienna, Austria.
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28
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Zhao X, Xiong L, Zhang M, Bai F. Towards efficient bioethanol production from agricultural and forestry residues: Exploration of unique natural microorganisms in combination with advanced strain engineering. BIORESOURCE TECHNOLOGY 2016; 215:84-91. [PMID: 27067672 DOI: 10.1016/j.biortech.2016.03.158] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Revised: 03/29/2016] [Accepted: 03/30/2016] [Indexed: 05/14/2023]
Abstract
Production of fuel ethanol from lignocellulosic feedstocks such as agricultural and forestry residues is receiving increasing attention due to the unsustainable supply of fossil fuels. Three key challenges include high cellulase production cost, toxicity of the cellulosic hydrolysate to microbial strains, and poor ability of fermenting microorganisms to utilize certain fermentable sugars in the hydrolysate. In this article, studies on searching of natural microbial strains for production of unique cellulase for biorefinery of agricultural and forestry wastes, as well as development of strains for improved cellulase production were reviewed. In addition, progress in the construction of yeast strains with improved stress tolerance and the capability to fully utilize xylose and glucose in the cellulosic hydrolysate was also summarized. With the superior microbial strains for high titer cellulase production and efficient utilization of all fermentable sugars in the hydrolysate, economic biofuels production from agricultural residues and forestry wastes can be realized.
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Affiliation(s)
- Xinqing Zhao
- State Key Laboratory of Microbial Metabolism, School of Life Science and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China.
| | - Liang Xiong
- School of Life Science and Biotechnology, Dalian University of Technology, Dalian 116024, China
| | - Mingming Zhang
- School of Life Science and Biotechnology, Dalian University of Technology, Dalian 116024, China
| | - Fengwu Bai
- State Key Laboratory of Microbial Metabolism, School of Life Science and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China; School of Life Science and Biotechnology, Dalian University of Technology, Dalian 116024, China
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29
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Genomic and transcriptomic analyses of the tangerine pathotype of Alternaria alternata in response to oxidative stress. Sci Rep 2016; 6:32437. [PMID: 27582273 PMCID: PMC5007530 DOI: 10.1038/srep32437] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Accepted: 08/09/2016] [Indexed: 12/19/2022] Open
Abstract
The tangerine pathotype of Alternaria alternata produces the A. citri toxin (ACT) and is the causal agent of citrus brown spot that results in significant yield losses worldwide. Both the production of ACT and the ability to detoxify reactive oxygen species (ROS) are required for A. alternata pathogenicity in citrus. In this study, we report the 34.41 Mb genome sequence of strain Z7 of the tangerine pathotype of A. alternata. The host selective ACT gene cluster in strain Z7 was identified, which included 25 genes with 19 of them not reported previously. Of these, 10 genes were present only in the tangerine pathotype, representing the most likely candidate genes for this pathotype specialization. A transcriptome analysis of the global effects of H2O2 on gene expression revealed 1108 up-regulated and 498 down-regulated genes. Expressions of those genes encoding catalase, peroxiredoxin, thioredoxin and glutathione were highly induced. Genes encoding several protein families including kinases, transcription factors, transporters, cytochrome P450, ubiquitin and heat shock proteins were found associated with adaptation to oxidative stress. Our data not only revealed the molecular basis of ACT biosynthesis but also provided new insights into the potential pathways that the phytopathogen A. alternata copes with oxidative stress.
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30
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Activating Intrinsic Carbohydrate-Active Enzymes of the Smut Fungus Ustilago maydis for the Degradation of Plant Cell Wall Components. Appl Environ Microbiol 2016; 82:5174-85. [PMID: 27316952 DOI: 10.1128/aem.00713-16] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Accepted: 06/10/2016] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED The microbial conversion of plant biomass to valuable products in a consolidated bioprocess could greatly increase the ecologic and economic impact of a biorefinery. Current strategies for hydrolyzing plant material mostly rely on the external application of carbohydrate-active enzymes (CAZymes). Alternatively, production organisms can be engineered to secrete CAZymes to reduce the reliance on externally added enzymes. Plant-pathogenic fungi have a vast repertoire of hydrolytic enzymes to sustain their lifestyle, but expression of the corresponding genes is usually highly regulated and restricted to the pathogenic phase. Here, we present a new strategy in using the biotrophic smut fungus Ustilago maydis for the degradation of plant cell wall components by activating its intrinsic enzyme potential during axenic growth. This fungal model organism is fully equipped with hydrolytic enzymes, and moreover, it naturally produces value-added substances, such as organic acids and biosurfactants. To achieve the deregulated expression of hydrolytic enzymes during the industrially relevant yeast-like growth in axenic culture, the native promoters of the respective genes were replaced by constitutively active synthetic promoters. This led to an enhanced conversion of xylan, cellobiose, and carboxymethyl cellulose to fermentable sugars. Moreover, a combination of strains with activated endoglucanase and β-glucanase increased the release of glucose from carboxymethyl cellulose and regenerated amorphous cellulose, suggesting that mixed cultivations could be a means for degrading more complex substrates in the future. In summary, this proof of principle demonstrates the potential applicability of activating the expression of native CAZymes from phytopathogens in a biocatalytic process. IMPORTANCE This study describes basic experiments that aim at the degradation of plant cell wall components by the smut fungus Ustilago maydis As a plant pathogen, this fungus contains a set of lignocellulose-degrading enzymes that may be suited for biomass degradation. However, its hydrolytic enzymes are specifically expressed only during plant infection. Here, we provide the proof of principle that these intrinsic enzymes can be synthetically activated during the industrially relevant yeast-like growth. The fungus is known to naturally synthesize valuable compounds, such as itaconate or glycolipids. Therefore, it could be suited for use in a consolidated bioprocess in which more complex and natural substrates are simultaneously converted to fermentable sugars and to value-added compounds in the future.
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31
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Gupta VK, Kubicek CP, Berrin JG, Wilson DW, Couturier M, Berlin A, Filho EXF, Ezeji T. Fungal Enzymes for Bio-Products from Sustainable and Waste Biomass. Trends Biochem Sci 2016; 41:633-645. [PMID: 27211037 DOI: 10.1016/j.tibs.2016.04.006] [Citation(s) in RCA: 142] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2015] [Revised: 04/13/2016] [Accepted: 04/22/2016] [Indexed: 12/19/2022]
Abstract
Lignocellulose, the most abundant renewable carbon source on earth, is the logical candidate to replace fossil carbon as the major biofuel raw material. Nevertheless, the technologies needed to convert lignocellulose into soluble products that can then be utilized by the chemical or fuel industries face several challenges. Enzymatic hydrolysis is of major importance, and we review the progress made in fungal enzyme technology over the past few years with major emphasis on (i) the enzymes needed for the conversion of polysaccharides (cellulose and hemicellulose) into soluble products, (ii) the potential uses of lignin degradation products, and (iii) current progress and bottlenecks for the use of the soluble lignocellulose derivatives in emerging biorefineries.
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Affiliation(s)
- Vijai K Gupta
- Molecular Glycobiotechnology Group, Discipline of Biochemistry, National University of Ireland Galway, Galway City, Ireland.
| | - Christian P Kubicek
- Biotechnology and Microbiology, Institute of Chemical Engineering, Technische Universität Wien, Gumpendorferstrasse, 1060 Wien, Austria
| | - Jean-Guy Berrin
- Institut National de la Recherche Agronomique (INRA), Unité Mixte de Recherche (UMR) 1163-Biodiversité et Biotechnologie Fongiques, Avenue de Luminy, 13288 Marseille, France; Aix Marseille Université, UMR1163 Biodiversité et Biotechnologie Fongiques, Avenue de Luminy, 13288 Marseille, France
| | - David W Wilson
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853, USA
| | - Marie Couturier
- Institut National de la Recherche Agronomique (INRA), Unité Mixte de Recherche (UMR) 1163-Biodiversité et Biotechnologie Fongiques, Avenue de Luminy, 13288 Marseille, France; Aix Marseille Université, UMR1163 Biodiversité et Biotechnologie Fongiques, Avenue de Luminy, 13288 Marseille, France
| | - Alex Berlin
- Novozymes, Inc., 1445 Drew Ave, Davis CA 95618 USA
| | - Edivaldo X F Filho
- Laboratory of Enzymology, Department of Cell Biology, University of Brasilia, Asa Norte, 70910-900 Brasilia, DF Brazil
| | - Thaddeus Ezeji
- Biotechnology and Fermentation Group, Department of Animal Sciences, Ohio State University and Ohio Agricultural Research and Development Center (OARDC), Madison Avenue, Wooster, OH 44691, USA
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