1
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Wang Q, Xiu J, Liu B, Shen L, Wang H, Fang C, Shan S. Enhanced fermentation and deconstruction of natural wheat straw by Trichoderma asperellum T-1 and its positive transcriptional response. BIORESOURCE TECHNOLOGY 2024; 406:130971. [PMID: 38897156 DOI: 10.1016/j.biortech.2024.130971] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2024] [Revised: 05/26/2024] [Accepted: 06/12/2024] [Indexed: 06/21/2024]
Abstract
Microorganisms harvest energy from agricultural waste by degrading its structure. By comparing with Trichoderma reesei QM6a in cellulase production, straw deconstruction and transcriptome response, Trichoderma asperellum T-1 was identified to be prioritized for the fermentation of natural straw. Cellulase activity of T-1 was 50%-102% higher than QM6a. And the degradation rate of hemicellulose and ligin in wheat straw by T-1 reached 40% and 42%. Time-driven changes in the gene expression of extracellular proteins involved in polysaccharide, xylan, and hemicellulose metabolism and hydrolysis indicated that T-1 positively responded in both solid state fermentation and submerged fermentation for lignocellulose degradation. A significantly enriched category encoding carbohydrate-binding modules is considered critical for the deconstruction of the natural structure by T-1. The findings highlight the superiority of T. asperellum T-1 in straw fermentation, base on which, the construction of efficient microbial agents is expected to enhance the utilization of biomass.
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Affiliation(s)
- Qun Wang
- Key Laboratory of Recycling and Eco‑treatment of Waste Biomass of Zhejiang Province, School of Environmental and Natural Resources, Zhejiang University of Science and Technology, Hangzhou 310023, China.
| | - Jianghui Xiu
- Key Laboratory of Recycling and Eco‑treatment of Waste Biomass of Zhejiang Province, School of Environmental and Natural Resources, Zhejiang University of Science and Technology, Hangzhou 310023, China
| | - Bingyang Liu
- Key Laboratory of Recycling and Eco‑treatment of Waste Biomass of Zhejiang Province, School of Environmental and Natural Resources, Zhejiang University of Science and Technology, Hangzhou 310023, China
| | - Linpei Shen
- Key Laboratory of Recycling and Eco‑treatment of Waste Biomass of Zhejiang Province, School of Environmental and Natural Resources, Zhejiang University of Science and Technology, Hangzhou 310023, China
| | - Hua Wang
- Key Laboratory of Recycling and Eco‑treatment of Waste Biomass of Zhejiang Province, School of Environmental and Natural Resources, Zhejiang University of Science and Technology, Hangzhou 310023, China
| | - Chengran Fang
- Key Laboratory of Recycling and Eco‑treatment of Waste Biomass of Zhejiang Province, School of Environmental and Natural Resources, Zhejiang University of Science and Technology, Hangzhou 310023, China; College of Civil Engineering, Zhejiang University of Technology, Hangzhou 310023, China
| | - Shengdao Shan
- Key Laboratory of Recycling and Eco‑treatment of Waste Biomass of Zhejiang Province, School of Environmental and Natural Resources, Zhejiang University of Science and Technology, Hangzhou 310023, China
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2
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Zhang Y, Li H, Xin Q, Zhao J, Xia T, Lu X. The role of glycosylation in non-productive adsorption of cellulase to lignin isolated from pretreated corn stover. Int J Biol Macromol 2024; 266:130836. [PMID: 38492700 DOI: 10.1016/j.ijbiomac.2024.130836] [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: 12/15/2023] [Revised: 03/01/2024] [Accepted: 03/11/2024] [Indexed: 03/18/2024]
Abstract
Glycosylation, a general post-translational modification for fungal cellulase, has been shown to affect cellulase binding to its substrate. However, the exact impact of glycosylation on cellulase-lignin interaction remain unclear. Here, we demonstrated that the lignin isolated from tetrahydrofuran-pretreated corn stover exhibits strong adsorption capability to cellulase due to its negatively charged and porous structure. For the cellulases with varying glycosylation levels, the less-glycosylated protein showed high adsorption capability to lignin, and that trend was observed for the main cellulase components secreted by Penicillium oxilicum, including endoglucanase PoCel5B, cellobiohydrolase PoCel7A-2, and β-glucosidase PoBgl1. Additionally, N-glycan sites and motifs were examined using mass spectrometry, and protein structures with N-glycans were constructed, where PoBgl1 and PoCel7A-2 contained 13 and 1 glycosylated sites respectively. The results of molecular dynamics simulations indicated that the N-glycans impacted on the solvent-accessible surface area and secondary structure of protein, and the binding conformation of lignin fragment on cellulase, resulting in a decrease in binding energy (14 kcal/mol for PoBgl1 and 13 kcal/mol for PoCel7A-2), particularly for van der Waals and electrostatic interaction. Those findings suggested that glycosylation negatively impacted the lignin-cellulase interaction, providing a theoretical basis for the rational engineering of enzymes to reduce lignin-enzyme interaction.
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Affiliation(s)
- Yuqing Zhang
- School of Bioengineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan, Shandong 250353, China
| | - Huiwen Li
- State Key Laboratory of Microbial Technology, Shandong University, No.72, Binhai Road, Qingdao 266237, China
| | - Qi Xin
- School of Bioengineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan, Shandong 250353, China
| | - Jian Zhao
- State Key Laboratory of Microbial Technology, Shandong University, No.72, Binhai Road, Qingdao 266237, China
| | - Tao Xia
- School of Bioengineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan, Shandong 250353, China.
| | - Xianqin Lu
- State Key Laboratory of Microbial Technology, Shandong University, No.72, Binhai Road, Qingdao 266237, China.
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3
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Hu C, Wang Y, Wang W, Cui W, Jia X, Mayo KH, Zhou Y, Su J, Yuan Y. A trapped covalent intermediate as a key catalytic element in the hydrolysis of a GH3 β-glucosidase: An X-ray crystallographic and biochemical study. Int J Biol Macromol 2024; 265:131131. [PMID: 38527679 DOI: 10.1016/j.ijbiomac.2024.131131] [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: 01/10/2024] [Revised: 03/21/2024] [Accepted: 03/22/2024] [Indexed: 03/27/2024]
Abstract
Glycoside hydrolases (GHs) are industrially important enzymes that hydrolyze glycosidic bonds in glycoconjugates. In this study, we found a GH3 β-glucosidase (CcBgl3B) from Cellulosimicrobium cellulans sp. 21 was able to selectively hydrolyze the β-1,6-glucosidic bond linked glucose of ginsenosides. X-ray crystallographic studies of the ligand complex ginsenoside-specific β-glucosidase provided a novel finding that support the catalytic mechanism of GH3. The substrate was clearly identified within the catalytic center of wild-type CcBgl3B, revealing that the C1 atom of the glucose was covalently bound to the Oδ1 group of the conserved catalytic nucleophile Asp264 as an enzyme-glycosyl intermediate. The glycosylated Asp264 could be identified by mass spectrometry. Through site-directed mutagenesis studies with Asp264, it was found that the covalent intermediate state formed by Asp264 and the substrate was critical for catalysis. In addition, Glu525 variants (E525A, E525Q and E525D) showed no or marginal activity against pNPβGlc; thus, this residue could supply a proton for the reaction. Overall, our study provides an insight into the catalytic mechanism of the GH3 enzyme CcBgl3B.
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Affiliation(s)
- Chenxing Hu
- Engineering Research Center of Glycoconjugates Ministry of Education, Jilin Provincial Key Laboratory of Chemistry and Biology of Changbai Mountain Natural Drugs, School of Life Sciences, Northeast Normal University, Changchun 130024, China
| | - Yibing Wang
- Engineering Research Center of Glycoconjugates Ministry of Education, Jilin Provincial Key Laboratory of Chemistry and Biology of Changbai Mountain Natural Drugs, School of Life Sciences, Northeast Normal University, Changchun 130024, China
| | - Weiyang Wang
- College of Life Science and Technology, Changchun University of Science & Technology, Changchun, Jilin 130022, China
| | - Wanli Cui
- Engineering Research Center of Glycoconjugates Ministry of Education, Jilin Provincial Key Laboratory of Chemistry and Biology of Changbai Mountain Natural Drugs, School of Life Sciences, Northeast Normal University, Changchun 130024, China
| | - Xinyue Jia
- Engineering Research Center of Glycoconjugates Ministry of Education, Jilin Provincial Key Laboratory of Chemistry and Biology of Changbai Mountain Natural Drugs, School of Life Sciences, Northeast Normal University, Changchun 130024, China
| | - Kevin H Mayo
- Department of Biochemistry, Molecular Biology & Biophysics, 6-155 Jackson Hall, University of Minnesota, Minneapolis, MN 55455, USA
| | - Yifa Zhou
- Engineering Research Center of Glycoconjugates Ministry of Education, Jilin Provincial Key Laboratory of Chemistry and Biology of Changbai Mountain Natural Drugs, School of Life Sciences, Northeast Normal University, Changchun 130024, China
| | - Jiyong Su
- Engineering Research Center of Glycoconjugates Ministry of Education, Jilin Provincial Key Laboratory of Chemistry and Biology of Changbai Mountain Natural Drugs, School of Life Sciences, Northeast Normal University, Changchun 130024, China.
| | - Ye Yuan
- Engineering Research Center of Glycoconjugates Ministry of Education, Jilin Provincial Key Laboratory of Chemistry and Biology of Changbai Mountain Natural Drugs, School of Life Sciences, Northeast Normal University, Changchun 130024, China.
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Zou Y, Li X, Xin X, Xu H, Zhao G. Microbial-Driven Synthesis and Hydrolysis of Neohesperidin Dihydrochalcone: Biotransformation Process and Feasibility Investigation. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2024; 72:4246-4256. [PMID: 38317352 DOI: 10.1021/acs.jafc.3c08339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2024]
Abstract
A novel yeast-mediated hydrogenation was developed for the synthesis of neohesperidin dihydrochalcone (NHDC) in high yields (over 83%). Moreover, whole-cell catalytic hydrolysis was also designed to hydrolyze NHDC into potential sweeteners, hesperetin dihydrochalcone-7-O-glucoside (HDC-G) and hesperetin dihydrochalcone (HDC). The biohydrogenation was further combined with whole-cell hydrolysis to achieve a one-pot two-step biosynthesis, utilizing yeast to hydrogenate C═C in the structure, while Aspergillus niger cells hydrolyze glycosides. The conversion of NHDC and the proportion of hydrolysis products could be controlled by adjusting the catalysts, the components of the reaction system, and the addition of glucose. Furthermore, yeast-mediated biotransformation demonstrated superior reaction stability and enhanced safety and employed more cost-effective catalysts compared to the traditional chemical hydrogenation of NHDC synthesis. This research not only provides a new route for NHDC production but also offers a safe and flexible one-pot cascade biosynthetic platform for the production of high-value compounds from citrus processing wastes.
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Affiliation(s)
- Yucong Zou
- School of Food Science and Engineering, South China University of Technology, Wushan Road 381, Guangzhou, Guangdong 510640, China
| | - Xiaofeng Li
- School of Food Science and Engineering, South China University of Technology, Wushan Road 381, Guangzhou, Guangdong 510640, China
| | - Xuan Xin
- College of Light Industry and Food Technology, Zhongkai University of Agriculture and Engineering, Dongsha Street 24, Guangzhou, Guangdong 510225, China
| | - Haixia Xu
- Jiangxi Key Laboratory National Products and Functional Food, College of Food Science and Engineering, Jiangxi Agricultural University, Nanchang, Jiangxi 3300045, China
| | - Guanglei Zhao
- State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Guangzhou, Guangdong 510641, China
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5
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Erkanli ME, El-Halabi K, Kim JR. Exploring the diversity of β-glucosidase: Classification, catalytic mechanism, molecular characteristics, kinetic models, and applications. Enzyme Microb Technol 2024; 173:110363. [PMID: 38041879 DOI: 10.1016/j.enzmictec.2023.110363] [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: 09/25/2023] [Revised: 11/17/2023] [Accepted: 11/18/2023] [Indexed: 12/04/2023]
Abstract
High-value chemicals and energy-related products can be produced from biomass. Biorefinery technology offers a sustainable and cost-effective method for this high-value conversion. β-glucosidase is one of the key enzymes in biorefinery processes, catalyzing the production of glucose from aryl-glycosides and cello-oligosaccharides via the hydrolysis of β-glycosidic bonds. Although β-glucosidase plays a critical catalytic role in the utilization of cellulosic biomass, its efficacy is often limited by substrate or product inhibitions, low thermostability, and/or insufficient catalytic activity. To provide a detailed overview of β-glucosidases and their benefits in certain desired applications, we collected and summarized extensive information from literature and public databases, covering β-glucosidases in different glycosidase hydrolase families and biological kingdoms. These β-glucosidases show differences in amino acid sequence, which are translated into varying degrees of the molecular properties critical in enzymatic applications. This review describes studies on the diversity of β-glucosidases related to the classification, catalytic mechanisms, key molecular characteristics, kinetics models, and applications, and highlights several β-glucosidases displaying high stability, activity, and resistance to glucose inhibition suitable for desired biotechnological applications.
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Affiliation(s)
- Mehmet Emre Erkanli
- Department of Chemical and Biomolecular Engineering, New York University, 6 MetroTech Center, Brooklyn, NY 11201, United States
| | - Khalid El-Halabi
- Department of Chemical and Biomolecular Engineering, New York University, 6 MetroTech Center, Brooklyn, NY 11201, United States
| | - Jin Ryoun Kim
- Department of Chemical and Biomolecular Engineering, New York University, 6 MetroTech Center, Brooklyn, NY 11201, United States.
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6
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Lu X, Li X, Zhao J. Improving enzymatic efficiency of β-glucosidases in cellulase system by altering its binding behavior to the insoluble substrate during bioconversion of lignocellulose. BIORESOURCE TECHNOLOGY 2024; 391:129974. [PMID: 37939741 DOI: 10.1016/j.biortech.2023.129974] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Revised: 10/31/2023] [Accepted: 11/01/2023] [Indexed: 11/10/2023]
Abstract
The enzymatic efficiency of β-glucosidases is influenced by their binding behavior onto insoluble substrates (cellulose and lignin) during bioconversion of lignocellulose. This study suggested that the Bgl3 protein (Aspergillus fumigatus) showed strong adsorption affinity to lignin and the Bgl1 protein (Penicillium oxalicum) tended to adsorb to cellulose. It indicated that the various surface properties of the fibronectin type Ш-like domain (FnIII) led to different binding properties of β-glucosidases by investigating their binding mechanism. By engineering β-glucosidases' FnIII domain, Bgl3-1 and Bgl1-3 were constructed, which both showed lower binding capacities to insoluble substrates. As well as for Bgl1-3, its sensitivity to the phenolic component was also eased. Based on that, the reconstructed protein showed high catalytic efficiency during the enzymatic hydrolysis of corn stover by effectively transforming cellobiose to glucose. Thus, this study provided a new strategy to engineer β-glucosidases to enhance their performance in the cellulase system.
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Affiliation(s)
- Xianqin Lu
- State Key Laboratory of Microbial Technology, Shandong University, No.72, Binhai Road, Qingdao 266237, China
| | - Xuezhi Li
- State Key Laboratory of Microbial Technology, Shandong University, No.72, Binhai Road, Qingdao 266237, China
| | - Jian Zhao
- State Key Laboratory of Microbial Technology, Shandong University, No.72, Binhai Road, Qingdao 266237, China.
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7
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Yanai T, Takahashi Y, Katsumura E, Sakai N, Takeshita K, Imaizumi R, Matsuura H, Hongo S, Waki T, Takahashi S, Yamamoto M, Kataoka K, Nakayama T, Yamashita S. Structural insights into a bacterial β-glucosidase capable of degrading sesaminol triglucoside to produce sesaminol: toward the understanding of the aglycone recognition mechanism by the C-terminal lid domain. J Biochem 2023; 174:335-344. [PMID: 37384427 DOI: 10.1093/jb/mvad048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Revised: 06/15/2023] [Accepted: 06/27/2023] [Indexed: 07/01/2023] Open
Abstract
The sesaminol triglucoside (STG)-hydrolyzing β-glucosidase from Paenibacillus sp. (PSTG1), which belongs to glycoside hydrolase family 3 (GH3), is a promising catalyst for the industrial production of sesaminol. We determined the X-ray crystal structure of PSTG1 with bound glycerol molecule in the putative active site. PSTG1 monomer contained typical three domains of GH3 with the active site in domain 1 (TIM barrel). In addition, PSTG1 contained an additional domain (domain 4) at the C-terminus that interacts with the active site of the other protomer as a lid in the dimer unit. Interestingly, the interface of domain 4 and the active site forms a hydrophobic cavity probably for recognizing the hydrophobic aglycone moiety of substrate. The short flexible loop region of TIM barrel was found to be approaching the interface of domain 4 and the active site. We found that n-heptyl-β-D-thioglucopyranoside detergent acts as an inhibitor for PSTG1. Thus, we propose that the recognition of hydrophobic aglycone moiety is important for PSTG1-catalyzed reactions. Domain 4 might be a potential target for elucidating the aglycone recognition mechanism of PSTG1 as well as for engineering PSTG1 to create a further excellent enzyme to degrade STG more efficiently to produce sesaminol.
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Key Words
- glycoside hydrolase family 3
- sesaminol triglucoside
- β-glucosidase.Abbreviations: STG, sesaminol triglucoside; PSTG1, STG-hydrolyzing β-glucosidase from Paenibacillus sp; GH3, Glycoside Hydrolase Family 3; TIM, Triosephosphate isomerase, Fn-III, Fibronectin type III; 2-SDG, 2-O-(β-D-glucopyranosyl)-β-D-glucopyranosylsesaminol; 6-SDG, 6-O-(β-D-glucopyranosyl)-β-D-glucopyranosylsesaminol; SMG, β-D-glucopyranosylsesaminol; HTG, n-Heptyl-beta-D-thioglucopyranoside; OTG, n-Octyl-β-D-glucoside; pNP-β-Glc, p-Nitrophenyl-β-D-glucopyranoside
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Affiliation(s)
- Taro Yanai
- Graduate School of Natural Science and Technology, Kanazawa University, Kakuma, Kanazawa 920-1192, Japan
| | - Yukino Takahashi
- Graduate School of Natural Science and Technology, Kanazawa University, Kakuma, Kanazawa 920-1192, Japan
| | - Eri Katsumura
- Graduate School of Natural Science and Technology, Kanazawa University, Kakuma, Kanazawa 920-1192, Japan
| | - Naoki Sakai
- RIKEN SPring-8 Center, Sayo-cho, Sayo-gun, Hyogo 679-5148, Japan
| | - Kohei Takeshita
- RIKEN SPring-8 Center, Sayo-cho, Sayo-gun, Hyogo 679-5148, Japan
| | - Riki Imaizumi
- Graduate School of Natural Science and Technology, Kanazawa University, Kakuma, Kanazawa 920-1192, Japan
| | - Hiroaki Matsuura
- RIKEN SPring-8 Center, Sayo-cho, Sayo-gun, Hyogo 679-5148, Japan
| | - Shuntaro Hongo
- Graduate School of Engineering, Tohoku University, Aoba 6-6-11, Aramaki, Aoba-ku, Sendai, Miyagi 980-8579, Japan
| | - Toshiyuki Waki
- Graduate School of Engineering, Tohoku University, Aoba 6-6-11, Aramaki, Aoba-ku, Sendai, Miyagi 980-8579, Japan
| | - Seiji Takahashi
- Graduate School of Engineering, Tohoku University, Aoba 6-6-11, Aramaki, Aoba-ku, Sendai, Miyagi 980-8579, Japan
| | - Masaki Yamamoto
- RIKEN SPring-8 Center, Sayo-cho, Sayo-gun, Hyogo 679-5148, Japan
| | - Kunishige Kataoka
- Graduate School of Natural Science and Technology, Kanazawa University, Kakuma, Kanazawa 920-1192, Japan
| | - Toru Nakayama
- Graduate School of Engineering, Tohoku University, Aoba 6-6-11, Aramaki, Aoba-ku, Sendai, Miyagi 980-8579, Japan
| | - Satoshi Yamashita
- Graduate School of Natural Science and Technology, Kanazawa University, Kakuma, Kanazawa 920-1192, Japan
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Li Z, Zhou Y, Xu C, Pan J, Li H, Zhou Y, Zou Y. Genome-wide analysis of the Pleurotus eryngii laccase gene (PeLac) family and functional identification of PeLac5. AMB Express 2023; 13:104. [PMID: 37768391 PMCID: PMC10539258 DOI: 10.1186/s13568-023-01608-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Accepted: 09/12/2023] [Indexed: 09/29/2023] Open
Abstract
The laccase gene family encodes multiple isozymes that are crucial for the degradation of substrates and the regulation of developmental processes in fungi. Pleurotus eryngii is an important edible and medicinal fungus belonging to the Basidiomycota phylum and can grow on a variety of natural substrates. In the present study, genome-wide profiling of P. eryngii identified 10 genes encoding its laccase isoenzymes. Conservative sequence analysis demonstrated that all PeLacs possess classical laccase structural domains. Phylogenetic analysis yielded four major subgroups, the members of which are similar with respect to conserved gene organization, protein domain architecture, and consensus motifs. The 10 PeLacs formed three groups together with 12 PoLacs in Pleurotus ostreatus, indicating that they share a high level of evolutionary homology. Cis-responsive element analysis implied that PeLacs genes play a role in growth and development and lignocellulose degradation. Targeted overexpression of PeLac5 reduced the time to primordia formation and their development to fruiting bodies. Gene expression patterns in the presence of different lignocellulosic substrates indicate that three PeLacs genes (2, 4, and 9) are key to lignocellulose degradation. This work presents the first inventory of laccase genes in P. eryngii and preliminarily explores their functions, which may help to uncover the manner by which these proteins utilize substrates.
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Affiliation(s)
- Zihao Li
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, Beijing, 100081, China
- Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Yuanyuan Zhou
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, Beijing, 100081, China
- Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Congtao Xu
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, Beijing, 100081, China
- Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Jinlong Pan
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, Beijing, 100081, China
- Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Haikang Li
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, Beijing, 100081, China
- Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Yi Zhou
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, Beijing, 100081, China
- Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Yajie Zou
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, Beijing, 100081, China.
- Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
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9
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Wang Z, Chen H, Qin Y, Lan T. Effect of Fenton oxidized lignin support on immobilized β-glucosidase activity. J Biotechnol 2023; 368:31-41. [PMID: 37028559 DOI: 10.1016/j.jbiotec.2023.04.002] [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: 12/14/2022] [Revised: 03/10/2023] [Accepted: 04/04/2023] [Indexed: 04/09/2023]
Abstract
In this study, the Fenton oxidized lignin was prepared to investigate the effect of Fenton oxidation modification on the activity of lignin immobilized β-glucosidase (β-GL). The results demonstrated that Fenton oxidation could significantly improve the activity and stability of immobilized β-GL. This is because the Fenton oxidation increased the electrostatic, hydrogen bonding, and hydrophobic forces between lignin and β-GL, resulting in increased lignin adsorption onto β-GL. The Fenton oxidation also changed the chemical structure of lignin, altering the lignin-β-GL binding site and reducing the negative effect of lignin on the β-GL catalytic domain. This research will improve understanding of the effect of Fenton lignin oxidation on immobilized β-GL activity and expand the use of lignin in enzyme immobilization.
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Affiliation(s)
- Zekang Wang
- Faculty of Food Science and Engineering, Kunming University of Science and Technology, 727 South Jingming Rd., Chenggong District, Kunming, 650500, China
| | - Haiyan Chen
- Faculty of Food Science and Engineering, Kunming University of Science and Technology, 727 South Jingming Rd., Chenggong District, Kunming, 650500, China
| | - Yuyue Qin
- Faculty of Food Science and Engineering, Kunming University of Science and Technology, 727 South Jingming Rd., Chenggong District, Kunming, 650500, China
| | - Tianqing Lan
- Faculty of Food Science and Engineering, Kunming University of Science and Technology, 727 South Jingming Rd., Chenggong District, Kunming, 650500, China; National Engineering Research Center of Rice and Byproduct Deep Processing, College of Food Science and Engineering, Central South University of Forestry and Technology, 498 South Shaoshan Rd., Tianxin District, Changsha, 410004, China.
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10
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Jia H, Feng X, Huang J, Guo Y, Zhang D, Li X, Zhao J. Recombinant Family 1 Carbohydrate-Binding Modules Derived From Fungal Cellulase Enhance Enzymatic Degradation of Lignocellulose as Novel Effective Accessory Protein. Front Microbiol 2022; 13:876466. [PMID: 35898911 PMCID: PMC9309510 DOI: 10.3389/fmicb.2022.876466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Accepted: 06/09/2022] [Indexed: 11/23/2022] Open
Abstract
Fungal cellulases usually contain a family 1 carbohydrate-binding module (CBM1), and its role was considered to recognize the substrate specifically. This study testified that the CBM1s derived from cellobiohydrolase I of Trichoderma reesei, Penicillium oxalicum, and Penicillium funiculosum could be used as an effective accessory protein in cellulase cocktails to enhance the saccharification of lignocellulose, and its enhancement effect was significantly superior to some reported accessory proteins, such as bovine serum albumin (BSA). The promoting effects of the CBM1s were related to not only the CBM1 sources and protein dosages, but also the substrate characteristics and solid consistency during enzymatic hydrolysis. The adsorption capacity of the CBM1s, the adsorption kinetic of TrCBM from T. reesei and cellobiohydrolase, endoglucanase, and β-glucosidase from P. oxalicum, and the effect of adding TrCBM on enzyme activities of free cellulases in the hydrolysis system were investigated, and the binding conformations and affinities of CBM1s to cellulose and lignin were predicted by molecular docking. It was speculated that the higher affinity of the CBM1s to lignin than cellulases could potentially enable the CBM1s to displace cellulase adsorbed on lignin or to preferentially adsorb onto lignin to avoid ineffective adsorption of cellulase onto lignin, which enhanced cellulase system efficiency during enzymatic hydrolysis of lignocellulose.
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Affiliation(s)
- Hexue Jia
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Xiaoting Feng
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Jiamin Huang
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Yingjie Guo
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
| | - Daolei Zhang
- School of Bioengineering, Shandong Polytechnic, Jinan, China
| | - Xuezhi Li
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
- *Correspondence: Xuezhi Li,
| | - Jian Zhao
- State Key Laboratory of Microbial Technology, Shandong University, Qingdao, China
- Jian Zhao,
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11
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Immobilization of an Industrial β-Glucosidase from Aspergillus fumigatus and Its Use for Cellobiose Hydrolysis. Processes (Basel) 2022. [DOI: 10.3390/pr10061225] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
In this study, several covalent methods of immobilization based on acrylic supports, Schiff bases and epoxides have been applied to a commercial cocktail with a high β-glucosidase activity secreted by Aspergillus fumigatus. This cocktail was preliminary compared to a commercial secretome of Aspergillus niger, which was also subjected to the aforementioned immobilization methods. Due to its higher activity, the cocktail from A. fumigatus immobilized on ReliZyme™ HA403 activated with glutaraldehyde was employed for pNPG and cellobiose hydrolysis in diverse operational conditions and at diverse enzyme loadings, showing a very high activity at high enzyme load. A kinetic model based on the Michaelis–Menten hypothesis, in which double inhibition occurs due to glucose, has been selected upon fitting it to all experimentally retrieved data with the lowest-activity immobilized enzyme. This model was compared to the one previously established for the free form of the enzyme, observing that cellobiose acompetitive inhibition does not exist with the immobilized enzyme acting as the biocatalyst. In addition, stability studies indicated that the immobilized enzyme intrinsically behaves as the free enzyme, as expected for a one-bond low-interaction protein-support immobilization.
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12
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Li M, Jiang B, Wu W, Wu S, Yang Y, Song J, Ahmad M, Jin Y. Current understanding and optimization strategies for efficient lignin-enzyme interaction: A review. Int J Biol Macromol 2022; 195:274-286. [PMID: 34883164 DOI: 10.1016/j.ijbiomac.2021.11.188] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Revised: 11/24/2021] [Accepted: 11/27/2021] [Indexed: 11/29/2022]
Abstract
From energy perspective, with abundant polysaccharides (45-85%), the renewable lignocellulosic is recognized as the 2nd generation feedstock for bioethanol and bio-based products production. Enzymatic hydrolysis is a critical pathway to yield fermentable monosaccharides from pretreated substrates of lignocellulose. Nevertheless, the lignin presence in lignocellulosic substrates leads to the low substrate enzymatic digestibility ascribed to the nonproductive adsorption. It has been reported that the water-soluble lignin (low molecular weight, sulfonated/sulfomethylated and graft polymer) enhance the rate of enzymatic digestibility, however, the catalytic mechanism of lignin-enzyme interaction remains elusive. In this review, optimization strategies for enzymatic hydrolysis based on the lignin structural modification, enzyme engineering, and different additives are critically reviewed. Lignin-enzyme interaction mechanism is also discussed (lignin and various cellulases). In addition, the mathematical models and simulation of lignin, cellulose and enzyme aims for promoting an integrated biomass-conversion process for sustainable production of value-added biofuels.
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Affiliation(s)
- Mohan Li
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, International Innovation Center for Forest Chemicals and Materials, China
| | - Bo Jiang
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, International Innovation Center for Forest Chemicals and Materials, China; Jiangsu Provincial Key Lab of Pulp and Paper Science and Technology, Nanjing Forestry University, Nanjing 210037, China
| | - Wenjuan Wu
- Jiangsu Provincial Key Lab of Pulp and Paper Science and Technology, Nanjing Forestry University, Nanjing 210037, China
| | - Shufang Wu
- Jiangsu Provincial Key Lab of Pulp and Paper Science and Technology, Nanjing Forestry University, Nanjing 210037, China
| | - Yiqin Yang
- Jiangsu Provincial Key Lab of Pulp and Paper Science and Technology, Nanjing Forestry University, Nanjing 210037, China
| | - Junlong Song
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, International Innovation Center for Forest Chemicals and Materials, China; Jiangsu Provincial Key Lab of Pulp and Paper Science and Technology, Nanjing Forestry University, Nanjing 210037, China
| | - Mehraj Ahmad
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, International Innovation Center for Forest Chemicals and Materials, China; Jiangsu Provincial Key Lab of Pulp and Paper Science and Technology, Nanjing Forestry University, Nanjing 210037, China
| | - Yongcan Jin
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, International Innovation Center for Forest Chemicals and Materials, China; Jiangsu Provincial Key Lab of Pulp and Paper Science and Technology, Nanjing Forestry University, Nanjing 210037, China.
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13
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Wang Y, Liu R, Liu H, Li X, Shen L, Zhang W, Song X, Liu W, Liu X, Zhong Y. Development of a powerful synthetic hybrid promoter to improve the cellulase system of Trichoderma reesei for efficient saccharification of corncob residues. Microb Cell Fact 2022; 21:5. [PMID: 34983541 PMCID: PMC8725555 DOI: 10.1186/s12934-021-01727-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2021] [Accepted: 12/17/2021] [Indexed: 02/07/2023] Open
Abstract
Background The filamentous fungus Trichoderma reesei is a widely used workhorse for cellulase production in industry due to its prominent secretion capacity of extracellular cellulolytic enzymes. However, some key components are not always sufficient in this cellulase cocktail, making the conversion of cellulose-based biomass costly on the industrial scale. Development of strong and efficient promoters would enable cellulase cocktail to be optimized for bioconversion of biomass. Results In this study, a synthetic hybrid promoter was constructed and applied to optimize the cellulolytic system of T. reesei for efficient saccharification towards corncob residues. Firstly, a series of 5’ truncated promoters in different lengths were established based on the strong constitutive promoter Pcdna1. The strongest promoter amongst them was Pcdna1-3 (− 640 to − 1 bp upstream of the translation initiation codon ATG), exhibiting a 1.4-fold higher activity than that of the native cdna1 promoter. Meanwhile, the activation region (− 821 to − 622 bp upstream of the translation initiation codon ATG and devoid of the Cre1-binding sites) of the strong inducible promoter Pcbh1 was cloned and identified to be an amplifier in initiating gene expression. Finally, this activation region was fused to the strongest promoter Pcdna1-3, generating the novel synthetic hybrid promoter Pcc. This engineered promoter Pcc drove strong gene expression by displaying 1.6- and 1.8-fold stronger fluorescence intensity than Pcbh1 and Pcdna1 under the inducible condition using egfp as the reporter gene, respectively. Furthermore, Pcc was applied to overexpress the Aspergillus niger β-glucosidase BGLA coding gene bglA and the native endoglucanase EG2 coding gene eg2, achieving 43.5-fold BGL activity and 1.2-fold EG activity increase, respectively. Ultimately, to overcome the defects of the native cellulase system in T. reesei, the bglA and eg2 were co-overexpressed under the control of Pcc promoter. The bglA-eg2 double expression strain QPEB70 exhibited a 178% increase in total cellulase activity, whose cellulase system displayed 2.3- and 2.4-fold higher saccharification efficiency towards acid-pretreated and delignified corncob residues than the parental strain, respectively. Conclusions The synthetic hybrid promoter Pcc was generated and employed to improve the cellulase system of T. reesei by expressing specific components. Therefore, construction of synthetic hybrid promoters would allow particular cellulase genes to be expressed at desired levels, which is a viable strategy to optimize the cellulolytic enzyme system for efficient biomass bioconversion. Supplementary Information The online version contains supplementary material available at 10.1186/s12934-021-01727-8.
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Affiliation(s)
- Yifan Wang
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, 266237, People's Republic of China
| | - Ruiyan Liu
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, 266237, People's Republic of China
| | - Hong Liu
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, 266237, People's Republic of China
| | - Xihai Li
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, 266237, People's Republic of China
| | - Linjing Shen
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, 266237, People's Republic of China
| | - Weican Zhang
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, 266237, People's Republic of China
| | - Xin Song
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, 266237, People's Republic of China
| | - Weifeng Liu
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, 266237, People's Republic of China
| | - Xiangmei Liu
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, 266237, People's Republic of China.
| | - Yaohua Zhong
- State Key Laboratory of Microbial Technology, Institute of Microbial Technology, Shandong University, Qingdao, 266237, People's Republic of China.
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14
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Xiong Q, Qiao J, Wang M, Li S, Li X. Carboxylated and quaternized lignin enhanced enzymatic hydrolysis of lignocellulose treated by p-toluenesulfonic acid due to improving enzyme activity. BIORESOURCE TECHNOLOGY 2021; 337:125465. [PMID: 34320745 DOI: 10.1016/j.biortech.2021.125465] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Revised: 06/20/2021] [Accepted: 06/23/2021] [Indexed: 06/13/2023]
Abstract
Modificated lignins can affect enzymatic hydrolysis efficiency (EHE) because of changing physicochemical properties of lignin. In this study, carboxylated and quaternized lignin (CQL) and hydroxymethylated lignin (HML) were prepared to explore the effect of lignin modification on cellulase adsorption and EHE of p-toluenesulfonic acid treated corn stover (PCS). The results showed that CQL enhanced EHE of PCS due to the higher β-glucosidase (β-GL) activity, resulting from the formation of CQL-β-GL complexes with a lower binding free energy and the improvement of β-GL conformation made by the binding of CQL and β-GL. However, the drop in EHE due to the addition of HML was consequent on β-GL deactivation that was because the binding site of HML and β-GL overlapped with the carbohydrate binding domain of β-GL, causing the decrease in β-GL activity compared with CQL. This study would help deeply elucidate the effect of modified lignins on EHE and cellulase adsorption.
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Affiliation(s)
- Qiang Xiong
- College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211816, China; SDIC Biotech Investment Co., Ltd., Beijing 100034, China
| | - Jie Qiao
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, No. 2 Xuelin Road, Nanjing 210097, China
| | - Minghui Wang
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, No. 2 Xuelin Road, Nanjing 210097, China
| | - Shuang Li
- College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211816, China
| | - Xiujuan Li
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, No. 2 Xuelin Road, Nanjing 210097, China.
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15
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Improvement of Enzymatic Saccharification of Cellulose-Containing Raw Materials Using Aspergillus niger. Processes (Basel) 2021. [DOI: 10.3390/pr9081360] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Enzymatic hydrolysis of cellulose-containing raw materials, using Aspergillus niger, were studied. Filter paper, secondary cellulose-containing or starch-containing raw materials, miscanthus cellulose after alkaline or acid pretreatment, and wood chip cellulose, were used as substrates. The study focused on a wild A. niger strain, treated, or not (control), by ultraviolet (UV) irradiations for 45, 60, or 120 min (UV45, UV60, or UV120), or by UV irradiation for 120 min followed by a chemical treatment with NaN3 + ItBr for 30 min or 80 min (UV120 + CH30 or UV120 + CH80). A mixture of all the A. niger strains (MIX) was also tested. A citrate buffer, at 50 mM, wasthe most suitable for enzymatic hydrolysis. As the UV exposure time increased to 2 h, the cellulase activity of the surviving culturewas increased (r = 0.706; p < 0.05). The enzymatic activities of the obtained strains, towards miscanthus cellulose, wood chips, and filter paper, were inferior to those obtained with commercial enzymes (8.6 versus 9.1 IU), in some cases. Under stationary hydrolysis at 37 °C, pH = 4.7, the enzymatic activity of A. niger UV120 + CH30 was 24.9 IU. The enzymatic hydrolysis of secondary raw materials, using treated A. niger strains, was themost effective at 37 °C. Similarly, the most effective treatment of miscanthus cellulose and wood chips occurred at 50 °C. The maximum conversion of cellulose to glucose was observed using miscanthus cellulose (with alkaline pretreatment), and the minimum conversion was observed when using wood chips. The greatest value of cellulase activity was evidenced in the starch-containing raw materials, indicating that A. niger can ferment not only through cellulase activity, but also via an amylolytic one.
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16
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Higasi PMR, Velasco JA, Pellegrini VOA, de Araújo EA, França BA, Keller MB, Labate CA, Blossom BM, Segato F, Polikarpov I. Light-stimulated T. thermophilus two-domain LPMO9H: Low-resolution SAXS model and synergy with cellulases. Carbohydr Polym 2021; 260:117814. [PMID: 33712158 DOI: 10.1016/j.carbpol.2021.117814] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2020] [Revised: 02/06/2021] [Accepted: 02/10/2021] [Indexed: 12/19/2022]
Abstract
Lytic polysaccharide monooxygenases (LPMOs), monocopper enzymes that oxidatively cleave recalcitrant polysaccharides, have important biotechnological applications. Thermothelomyces thermophilus is a rich source of biomass-active enzymes, including many members from auxiliary activities family 9 LPMOs. Here, we report biochemical and structural characterization of recombinant TtLPMO9H which oxidizes cellulose at the C1 and C4 positions and shows enhanced activity in light-driven catalysis assays. TtLPMO9H also shows activity against xyloglucan. The addition of TtLPMO9H to endoglucanases from four different glucoside hydrolase families (GH5, GH12, GH45 and GH7) revealed that the product formation was remarkably increased when TtLPMO9H was combined with GH7 endoglucanase. Finally, we determind the first low resolution small-angle X-ray scattering model of the two-domain TtLPMO9H in solution that shows relative positions of its two functional domains and a conformation of the linker peptide, which can be relevant for the catalytic oxidation of cellulose and xyloglucan.
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Affiliation(s)
- Paula M R Higasi
- São Carlos Institute of Physics, University of São Paulo, Av. Trabalhador São-carlense 400, São Carlos, São Paulo, Brazil
| | - Josman A Velasco
- Lorena School of Engineering, University of São Paulo, Estrada Municipal do Campinho s/n, Lorena, São Paulo, Brazil
| | - Vanessa O A Pellegrini
- São Carlos Institute of Physics, University of São Paulo, Av. Trabalhador São-carlense 400, São Carlos, São Paulo, Brazil
| | - Evandro A de Araújo
- São Carlos Institute of Physics, University of São Paulo, Av. Trabalhador São-carlense 400, São Carlos, São Paulo, Brazil
| | - Bruno Alves França
- Lorena School of Engineering, University of São Paulo, Estrada Municipal do Campinho s/n, Lorena, São Paulo, Brazil
| | - Malene B Keller
- Department of Geosciences and Natural Resource Management, University of Copenhagen, Rolighedsvej 23, 1958 Frederiksberg C, Denmark
| | - Carlos A Labate
- Luiz de Queiroz College of Agriculture, University of São Paulo, Av. Pádua Dias 11, Piracicaba, São Paulo, Brazil
| | - Benedikt M Blossom
- Department of Geosciences and Natural Resource Management, University of Copenhagen, Rolighedsvej 23, 1958 Frederiksberg C, Denmark
| | - Fernando Segato
- Lorena School of Engineering, University of São Paulo, Estrada Municipal do Campinho s/n, Lorena, São Paulo, Brazil
| | - Igor Polikarpov
- São Carlos Institute of Physics, University of São Paulo, Av. Trabalhador São-carlense 400, São Carlos, São Paulo, Brazil.
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Méndez-Líter JA, de Eugenio LI, Hakalin NLS, Prieto A, Martínez MJ. Production of a β-Glucosidase-Rich Cocktail from Talaromyces amestolkiae Using Raw Glycerol: Its Role for Lignocellulose Waste Valorization. J Fungi (Basel) 2021; 7:jof7050363. [PMID: 34066619 PMCID: PMC8148544 DOI: 10.3390/jof7050363] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Revised: 04/28/2021] [Accepted: 05/03/2021] [Indexed: 11/22/2022] Open
Abstract
As β-glucosidases represent the major bottleneck for the industrial degradation of plant biomass, great efforts are being devoted to discover both novel and robust versions of these enzymes, as well as to develop efficient and inexpensive ways to produce them. In this work, raw glycerol from chemical production of biodiesel was tested as carbon source for the fungus Talaromyces amestolkiae with the aim of producing enzyme β-glucosidase-enriched cocktails. Approximately 11 U/mL β-glucosidase was detected in these cultures, constituting the major cellulolytic activity. Proteomic analysis showed BGL-3 as the most abundant protein and the main β-glucosidase. This crude enzyme was successfully used to supplement a basal commercial cellulolytic cocktail (Celluclast 1.5 L) for saccharification of pretreated wheat straw, corroborating that even hardly exploitable industrial wastes, such as glycerol, can be used as secondary raw materials to produce valuable enzymatic preparations in a framework of the circular economy.
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18
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Nguyen KHV, Dao TK, Nguyen HD, Nguyen KH, Nguyen TQ, Nguyen TT, Nguyen TMP, Truong NH, Do TH. Some characters of bacterial cellulases in goats' rumen elucidated by metagenomic DNA analysis and the role of fibronectin 3 module for endoglucanase function. Anim Biosci 2021; 34:867-879. [PMID: 32882773 PMCID: PMC8100471 DOI: 10.5713/ajas.20.0115] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2020] [Accepted: 07/19/2020] [Indexed: 12/20/2022] Open
Abstract
Objective Fibronectin 3 (FN3) and immunoglobulin like modules (Ig) are usually collocated beside modular cellulase catalytic domains. However, very few researches have investigated the role of these modules. In a previous study, we have sequenced and analyzed bacterial metagenomic DNA in Vietnamese goats’ rumen and found that cellulase-producing bacteria and cellulase families were dominant. In this study, the properties of modular cellulases and the role of a FN3 in unique endoglucanase belonging to glycosyl hydorlase (GH) family 5 were determined. Methods Based on Pfam analysis, the cellulases sequences containing FN3, Ig modules were extracted from 297 complete open reading frames (ORFs). The alkaline, thermostability, tertiary structure of deduced enzymes were predicted by AcalPred, TBI software, Phyre2 and Swiss models. Then, whole and truncated forms of a selected gene were expressed in Escherichia coli and purified by His-tag affinity column for assessment of FN3 ability to enhance enzyme activity, solubility and conformation. Results From 297 complete ORFs coding for cellulases, 148 sequences containing FN3, Ig were identified. Mostly FN3 appeared in 90.9% beta-glucosidases belonging to glycosyl hydrolase family 3 (GH3) and situated downstream of catalytic domains. The Ig was found upstream of 100% endoglucanase GH9. Rarely FN3 was seen to be situated downstream of X domain and upstream of catalytic domain endoglucanase GH5. Whole enzyme (called XFN3GH5 based on modular structure) and truncate forms FN3, XFN3, FN3GH5, GH5 were cloned in pET22b (+) and pET22SUMO to be expressed in single and fusion forms with a small ubiquitin-related modifier partner (S). The FN3, SFN3 increased GH5 solubility in FN3GH5, SFN3GH5. The SFN3 partly served for GH5 conformation in SFN3GH5, increased modules interaction and enzyme-soluble substrate affinity to enhance SXFN3GH5, SFN3GH5 activities in mixtures. Both SFN3 and SXFN3 did not anchor enzyme on filter paper but exfoliate and separate cellulose chains on filter paper for enzyme hydrolysis. Conclusion Based on these findings, the presence of FN3 module in certain cellulases was confirmed and it assisted for enzyme conformation and activity in both soluble and insoluble substrate.
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19
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Braham SA, Siar EH, Arana-Peña S, Bavandi H, Carballares D, Morellon-Sterling R, de Andrades D, Kornecki JF, Fernandez-Lafuente R. Positive effect of glycerol on the stability of immobilized enzymes: Is it a universal fact? Process Biochem 2021. [DOI: 10.1016/j.procbio.2020.12.015] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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20
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Effect of Concentrated Salts Solutions on the Stability of Immobilized Enzymes: Influence of Inactivation Conditions and Immobilization Protocol. Molecules 2021; 26:molecules26040968. [PMID: 33673063 PMCID: PMC7918437 DOI: 10.3390/molecules26040968] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Revised: 02/08/2021] [Accepted: 02/09/2021] [Indexed: 12/13/2022] Open
Abstract
This paper aims to investigate the effects of some salts (NaCl, (NH4)2SO4 and Na2SO4) at pH 5.0, 7.0 and 9.0 on the stability of 13 different immobilized enzymes: five lipases, three proteases, two glycosidases, and one laccase, penicillin G acylase and catalase. The enzymes were immobilized to prevent their aggregation. Lipases were immobilized via interfacial activation on octyl agarose or on glutaraldehyde-amino agarose beads, proteases on glyoxyl agarose or glutaraldehyde-amino agarose beads. The use of high concentrations of salts usually has some effects on enzyme stability, but the intensity and nature of these effects depends on the inactivation pH, nature and concentration of the salt, enzyme and immobilization protocol. The same salt can be a stabilizing or a destabilizing agent for a specific enzyme depending on its concentration, inactivation pH and immobilization protocol. Using lipases, (NH4)2SO4 generally permits the highest stabilities (although this is not a universal rule), but using the other enzymes this salt is in many instances a destabilizing agent. At pH 9.0, it is more likely to find a salt destabilizing effect than at pH 7.0. Results confirm the difficulty of foreseeing the effect of high concentrations of salts in a specific immobilized enzyme.
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21
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Kornecki JF, Carballares D, Morellon-Sterling R, Siar EH, Kashefi S, Chafiaa M, Arana-Peña S, Rios NS, Gonçalves LR, Fernandez-Lafuente R. Influence of phosphate anions on the stability of immobilized enzymes. Effect of enzyme nature, immobilization protocol and inactivation conditions. Process Biochem 2020. [DOI: 10.1016/j.procbio.2020.02.025] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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Sidar A, Albuquerque ED, Voshol GP, Ram AFJ, Vijgenboom E, Punt PJ. Carbohydrate Binding Modules: Diversity of Domain Architecture in Amylases and Cellulases From Filamentous Microorganisms. Front Bioeng Biotechnol 2020; 8:871. [PMID: 32850729 PMCID: PMC7410926 DOI: 10.3389/fbioe.2020.00871] [Citation(s) in RCA: 64] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Accepted: 07/07/2020] [Indexed: 12/11/2022] Open
Abstract
Enzymatic degradation of abundant renewable polysaccharides such as cellulose and starch is a field that has the attention of both the industrial and scientific community. Most of the polysaccharide degrading enzymes are classified into several glycoside hydrolase families. They are often organized in a modular manner which includes a catalytic domain connected to one or more carbohydrate-binding modules. The carbohydrate-binding modules (CBM) have been shown to increase the proximity of the enzyme to its substrate, especially for insoluble substrates. Therefore, these modules are considered to enhance enzymatic hydrolysis. These properties have played an important role in many biotechnological applications with the aim to improve the efficiency of polysaccharide degradation. The domain organization of glycoside hydrolases (GHs) equipped with one or more CBM does vary within organisms. This review comprehensively highlights the presence of CBM as ancillary modules and explores the diversity of GHs carrying one or more of these modules that actively act either on cellulose or starch. Special emphasis is given to the cellulase and amylase distribution within the filamentous microorganisms from the genera of Streptomyces and Aspergillus that are well known to have a great capacity for secreting a wide range of these polysaccharide degrading enzyme. The potential of the CBM and other ancillary domains for the design of improved polysaccharide decomposing enzymes is discussed.
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Affiliation(s)
- Andika Sidar
- Department of Microbial Biotechnology, Institute of Biology Leiden, Leiden, Netherlands.,Department of Food Science and Agricultural Product Technology, Faculty of Agricultural Technology, Universitas Gadjah Mada, Yogyakarta, Indonesia
| | - Erica D Albuquerque
- Department of Microbial Biotechnology, Institute of Biology Leiden, Leiden, Netherlands.,Sun Pharmaceutical Industries Europe BV., Hoofddorp, Netherlands
| | - Gerben P Voshol
- Department of Microbial Biotechnology, Institute of Biology Leiden, Leiden, Netherlands.,Dutch DNA Biotech B.V., Utrecht, Netherlands
| | - Arthur F J Ram
- Department of Microbial Biotechnology, Institute of Biology Leiden, Leiden, Netherlands
| | - Erik Vijgenboom
- Department of Microbial Biotechnology, Institute of Biology Leiden, Leiden, Netherlands
| | - Peter J Punt
- Department of Microbial Biotechnology, Institute of Biology Leiden, Leiden, Netherlands.,Dutch DNA Biotech B.V., Utrecht, Netherlands
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Stabilization of Glycosylated β-Glucosidase by Intramolecular Crosslinking Between Oxidized Glycosidic Chains and Lysine Residues. Appl Biochem Biotechnol 2020; 192:325-337. [DOI: 10.1007/s12010-020-03321-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Accepted: 04/23/2020] [Indexed: 02/06/2023]
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24
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Deng X, Du B, Zhu F, Gao Y, Li J. Proteomic analysis of Aspergillus niger 3.316 under heat stress. Microbiologyopen 2020; 9:e1012. [PMID: 32107876 PMCID: PMC7221434 DOI: 10.1002/mbo3.1012] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Revised: 01/25/2020] [Accepted: 02/01/2020] [Indexed: 01/04/2023] Open
Abstract
β-Glucosidase production by Aspergillus niger is accompanied by an inevitable temperature increase in the industrial fermentation environment. Hence, the synthetic process of β-glucosidase is negatively affected. However, our understanding of the heat stress response (HSR) mechanism in A. niger is still incomplete. The current study explored the intracellular proteome profile of A. niger 3.316 in group T (50°C stress) and group C (30°C control) using two proteomic approaches (isobaric tags for relative and absolute quantitation [iTRAQ] and label-free) and examined the expression of four proteins using a parallel reaction monitoring (PRM) approach. Based on the result of the iTRAQ proteomic analysis, 1,025 proteins were differentially expressed in group T compared to group C. Using the label-free approach, we only focused on 77 proteins with significant changes in their protein expression levels. In addition, we performed bioinformatics analysis on all these proteins and obtained detailed gene ontology (GO) enrichment and Kyoto encyclopedia of genes and genomes (KEGG) pathway results. Under heat stress conditions, the relative expression levels of proteins with protection and repair functions were upregulated in A. niger 3.316. These proteins were involved in metabolic pathways, oxidative phosphorylation, porphyrin and chlorophyll metabolism, pyruvate metabolism, and the citrate cycle (TCA cycle). The insights obtained from the presented proteomics and bioinformatics analyses can be used to further explore the HSR mechanism of A. niger.
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Affiliation(s)
- Xiangyu Deng
- Hebei Normal University of Science and TechnologyCollege of Food Science and TechnologyQinhuangdaoChina
| | - Bin Du
- Hebei Normal University of Science and TechnologyCollege of Food Science and TechnologyQinhuangdaoChina
| | - Fengmei Zhu
- Hebei Normal University of Science and TechnologyCollege of Food Science and TechnologyQinhuangdaoChina
| | - Yanan Gao
- Hebei Normal University of Science and TechnologyCollege of Food Science and TechnologyQinhuangdaoChina
| | - Jun Li
- Hebei Normal University of Science and TechnologyCollege of Food Science and TechnologyQinhuangdaoChina
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Hammerer F, Ostadjoo S, Friščić T, Auclair K. Towards Controlling the Reactivity of Enzymes in Mechanochemistry: Inert Surfaces Protect β-Glucosidase Activity During Ball Milling. CHEMSUSCHEM 2020; 13:106-110. [PMID: 31593363 DOI: 10.1002/cssc.201902752] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Indexed: 06/10/2023]
Abstract
The activity of β-glucosidases-the enzymes responsible for the final step in the enzymatic conversion of cellulose to glucose-can be maintained and manipulated under mechanochemical conditions in the absence of bulk solvent, either through an unexpected stabilization effect of inert surfaces, or by altering the enzymatic equilibrium. The reported results illustrate unique aspects of mechanoenzymatic reactions that are not observable in conventional aqueous solutions. They also represent the first reported strategies to enhance activity and favor either direction of the reaction under mechanochemical conditions.
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Affiliation(s)
- Fabien Hammerer
- Chemistry Department, McGill University, 801 Sherbrooke St. W., Montreal (QC), H3A 0B8, Canada
| | - Shaghayegh Ostadjoo
- Chemistry Department, McGill University, 801 Sherbrooke St. W., Montreal (QC), H3A 0B8, Canada
| | - Tomislav Friščić
- Chemistry Department, McGill University, 801 Sherbrooke St. W., Montreal (QC), H3A 0B8, Canada
| | - Karine Auclair
- Chemistry Department, McGill University, 801 Sherbrooke St. W., Montreal (QC), H3A 0B8, Canada
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Kashani-Amin E, Sakhteman A, Larijani B, Ebrahim-Habibi A. Presence of carbohydrate binding modules in extracellular region of class C G-protein coupled receptors (C GPCR): An in silico investigation on sweet taste receptor. J Biosci 2019; 44:138. [PMID: 31894119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Sweet taste receptor (STR) is a C GPCR family member and a suggested drug target for metabolic disorders such as diabetes. Detailed characteristics of the molecule as well as its ligand interactions mode are yet considerably unclear due to experimental study limitations of transmembrane proteins. An in silico study was designed to find the putative carbohydrate binding sites on STR. To this end, α-D-glucose and its α-1,4-oligomers (degree of polymerization up to 14) were chosen as probes and docked into an ensemble of different conformations of the extracellular region of STR monomers (T1R2 and T1R3), using AutoDock Vina. Ensembles had been sampled from an MD simulation experiment. Best poses were further energy-minimized in the presence of water molecules with Amber14 forcefield. For each monomer, four distinct binding regions consisting of one or two binding pockets could be distinguished. These regions were further investigated with regard to hydrophobicity and hydrophilicity of the residues, as well as residue compositions and non-covalent interactions with ligands. Popular binding regions showed similar characteristics to carbohydrate binding modules (CBM). Observation of several conserved or semi-conserved residues in these binding regions suggests a possibility to extrapolate the results to other C GPCR family members. In conclusion, presence of CBM in STR and, by extrapolation, in other C GPCR family members is suggested, similar to previously proposed sites in gut fungal C GPCRs, through transcriptome analyses. STR modes of interaction with carbohydrates are also discussed and characteristics of non-covalent interactions in C GPCR family are highlighted.
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Affiliation(s)
- Elaheh Kashani-Amin
- Biosensor Research Center, Endocrinology and Metabolism Molecular-Cellular Sciences Institute, Tehran University of Medical Sciences, Tehran, Iran
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Crystal Structure of a GH3 β-Glucosidase from the Thermophilic Fungus Chaetomium thermophilum. Int J Mol Sci 2019; 20:ijms20235962. [PMID: 31783503 PMCID: PMC6929035 DOI: 10.3390/ijms20235962] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Revised: 11/20/2019] [Accepted: 11/25/2019] [Indexed: 11/17/2022] Open
Abstract
Beta-glucosidases (β-glucosidases) have attracted considerable attention in recent years for use in various biotechnological applications. They are also essential enzymes for lignocellulose degradation in biofuel production. However, cost-effective biomass conversion requires the use of highly efficient enzymes. Thus, the search for new enzymes as better alternatives of the currently available enzyme preparations is highly important. Thermophilic fungi are nowadays considered as a promising source of enzymes with improved stability. Here, the crystal structure of a family GH3 β-glucosidase from the thermophilic fungus Chaetomium thermophilum (CtBGL) was determined at a resolution of 2.99 Å. The structure showed the three-domain architecture found in other β-glucosidases with variations in loops and linker regions. The active site catalytic residues in CtBGL were identified as Asp287 (nucleophile) and Glu517 (acid/base). Structural comparison of CtBGL with Protein Data Bank (PDB)-deposited structures revealed variations among glycosylated Asn residues. The enzyme displayed moderate glycosylation compared to other GH3 family β-glucosidases with similar structure. A new glycosylation site at position Asn504 was identified in CtBGL. Moreover, comparison with respect to several thermostability parameters suggested that glycosylation and charged residues involved in electrostatic interactions may contribute to the stability of the enzyme at elevated temperatures. The reported CtBGL structure provides additional insights into the family GH3 enzymes and could offer new ideas for further improvements in β-glucosidases for more efficient use in biotechnological applications regarding cellulose degradation.
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Purahong W, Sadubsarn D, Tanunchai B, Wahdan SFM, Sansupa C, Noll M, Wu YT, Buscot F. First Insights into the Microbiome of a Mangrove Tree Reveal Significant Differences in Taxonomic and Functional Composition among Plant and Soil Compartments. Microorganisms 2019; 7:microorganisms7120585. [PMID: 31756976 PMCID: PMC6955992 DOI: 10.3390/microorganisms7120585] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Revised: 11/06/2019] [Accepted: 11/14/2019] [Indexed: 12/17/2022] Open
Abstract
Mangrove forest trees play important ecological functions at the interface between terrestrial and marine ecosystems. However, despite playing crucial roles in plant health and productivity, there is little information on microbiomes of the tree species in mangrove ecosystems. Thus, in this study we aimed to characterize the microbiome in soil (rhizosphere) and plant (root, stem, and leaf endosphere) compartments of the widely distributed mangrove tree Rhizophora stylosa. Surprisingly, bacterial operational taxonomic units (OTUs) were only confidently detected in rhizosphere soil, while fungal OTUs were detected in all soil and plant compartments. The major detected bacterial phyla were affiliated to Proteobacteria, Actinobacteria, Planctomycetes, and Chloroflexi. Several nitrogen-fixing bacterial OTUs were detected, and the presence of nitrogen-fixing bacteria was confirmed by nifH gene based-PCR in all rhizosphere soil samples, indicating their involvement in N acquisition in the focal mangrove ecosystem. We detected taxonomically (54 families, 83 genera) and functionally diverse fungi in the R. stylosa mycobiome. Ascomycota (mainly Dothideomycetes, Eurotiomycetes, Sordariomycetes) were most diverse in the mycobiome, accounting for 86% of total detected fungal OTUs. We found significant differences in fungal taxonomic and functional community composition among the soil and plant compartments. We also detected significant differences in fungal OTU richness (p < 0.002) and community composition (p < 0.001) among plant compartments. The results provide the first information on the microbiome of rhizosphere soil to leaf compartments of mangrove trees and associated indications of ecological functions in mangrove ecosystems.
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Affiliation(s)
- Witoon Purahong
- Department of Soil Ecology, UFZ-Helmholtz Centre for Environmental Research, 06120 Halle (Saale), Germany; (D.S.); (B.T.); (S.F.M.W.); (C.S.); (F.B.)
- Correspondence: (W.P.); (Y.-T.W.)
| | - Dolaya Sadubsarn
- Department of Soil Ecology, UFZ-Helmholtz Centre for Environmental Research, 06120 Halle (Saale), Germany; (D.S.); (B.T.); (S.F.M.W.); (C.S.); (F.B.)
- Department of Bio and Process Engineering, Faculty of Medical Life and Science, Furtwangen University, 78054 VS-Schwenningen, Germany
| | - Benjawan Tanunchai
- Department of Soil Ecology, UFZ-Helmholtz Centre for Environmental Research, 06120 Halle (Saale), Germany; (D.S.); (B.T.); (S.F.M.W.); (C.S.); (F.B.)
| | - Sara Fareed Mohamed Wahdan
- Department of Soil Ecology, UFZ-Helmholtz Centre for Environmental Research, 06120 Halle (Saale), Germany; (D.S.); (B.T.); (S.F.M.W.); (C.S.); (F.B.)
- Department of Botany, Faculty of Science, Suez Canal University, 41522 Ismailia, Egypt
| | - Chakriya Sansupa
- Department of Soil Ecology, UFZ-Helmholtz Centre for Environmental Research, 06120 Halle (Saale), Germany; (D.S.); (B.T.); (S.F.M.W.); (C.S.); (F.B.)
- Biology Department, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand
- Graduate School, Chiang Mai University, Chiang Mai 50200, Thailand
| | - Matthias Noll
- Institute for Bioanalysis, Coburg University of Applied Sciences and Arts, 96450 Coburg, Germany;
| | - Yu-Ting Wu
- Department of Forestry, National Pingtung University of Science and Technology, Pingtung 91201, Taiwan
- Correspondence: (W.P.); (Y.-T.W.)
| | - François Buscot
- Department of Soil Ecology, UFZ-Helmholtz Centre for Environmental Research, 06120 Halle (Saale), Germany; (D.S.); (B.T.); (S.F.M.W.); (C.S.); (F.B.)
- German Centre for Integrative Biodiversity Research (iDiv), 04103 Leipzig, Germany
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Presence of carbohydrate binding modules in extracellular region of class C G-protein coupled receptors (C GPCR): An in silico investigation on sweet taste receptor. J Biosci 2019. [DOI: 10.1007/s12038-019-9944-9] [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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30
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Yang Z, Liao Y, Fu X, Zaporski J, Peters S, Jamison M, Liu Y, Wullschleger SD, Graham DE, Gu B. Temperature sensitivity of mineral-enzyme interactions on the hydrolysis of cellobiose and indican by β-glucosidase. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 686:1194-1201. [PMID: 31412515 DOI: 10.1016/j.scitotenv.2019.05.479] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Revised: 05/30/2019] [Accepted: 05/31/2019] [Indexed: 06/10/2023]
Abstract
Extracellular enzymes are mainly responsible for depolymerizing soil organic matter (SOM) in terrestrial ecosystems, and soil minerals are known to affect enzyme activity. However, the mechanisms and the effects of mineral-enzyme interactions on enzymatic degradation of organic matter remain poorly understood. In this study, we examined the adsorption of fungal β-glucosidase enzyme on minerals and time-dependent changes of enzymatic reactivity, measured by the degradation of two organic substrates (i.e., cellobiose and indican) under both cold (4 °C) and warm (20 and 30 °C) conditions. Hematite, kaolinite, and montmorillonite were used, to represent three common soil minerals with distinctly different surface charges and characteristics. β-glucosidase was found to sorb more strongly onto hematite and kaolinite than montmorillonite. All three minerals inhibited enzyme degradation of cellobiose and indican, likely due to the inactivation or hindrance of enzyme active sites. The mineral-bound β-glucosidase retained its specificity for organic substrate degradation, and increasing temperature from 4 to 30 °C enhanced the degradation rates by 2-4 fold for indican and 5-9 fold for cellobiose. These results indicate that enzyme adsorption, mineral type, temperature, and organic substrate specificity are important factors influencing enzymatic reactivity and thus have important implications in further understanding and modeling complex enzyme-facilitated SOM transformations in terrestrial ecosystems.
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Affiliation(s)
- Ziming Yang
- Department of Chemistry, Oakland University, Rochester, MI, 48309, USA; Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA.
| | - Yiju Liao
- Department of Chemistry, Oakland University, Rochester, MI, 48309, USA
| | - Xuan Fu
- Department of Chemistry, Oakland University, Rochester, MI, 48309, USA
| | - Jared Zaporski
- Department of Chemistry, Oakland University, Rochester, MI, 48309, USA
| | - Stephanie Peters
- Department of Chemistry, Oakland University, Rochester, MI, 48309, USA
| | - Megan Jamison
- Department of Chemistry, Oakland University, Rochester, MI, 48309, USA
| | - Yurong Liu
- College of Resources and Environment, Huazhong Agricultural University, Wuhan, 430070, China
| | - Stan D Wullschleger
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - David E Graham
- Biosciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA
| | - Baohua Gu
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN, 37831, USA.
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31
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Effects of intron retention on properties of β-glucosidase in Aspergillus niger. Fungal Biol 2019; 123:465-470. [DOI: 10.1016/j.funbio.2019.04.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2018] [Revised: 02/03/2019] [Accepted: 04/09/2019] [Indexed: 01/20/2023]
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Studies of adsorptive capacity of bacterial β-glucosidases on lignocresol aiming the enzymatic recycling in bioprocesses. ACTA ACUST UNITED AC 2019; 23:e00326. [PMID: 30984571 PMCID: PMC6444126 DOI: 10.1016/j.btre.2019.e00326] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Revised: 03/11/2019] [Accepted: 03/19/2019] [Indexed: 11/30/2022]
Abstract
Lignocresol has great capacity for use in recovery and enzymatic recycling in bioprocesses due to its adsorptive capacity. The adsorption of TpBgl3 to Lignocresol is higher compared to TpBgl1. The interactions between lignocresol and enzymes are influenced by electrostatic characteristics, and surface hydrophobicity. Glucose does not affect the adsorption of enzymes onto lignocresol. TpBgl1 bound to lignocresol maintains a residual enzymatic activity.
Enzymes are essential in many biological processes, including second-generation ethanol production. However, enzymes are one of the main expenses for the industrial process in these days. Several studies have been done to maximize cost savings, however, many processes are still economically infeasible. In this study, we report the synthesis of a suspension of lignocresol for recycling or reuse of enzymes in bioprocesses. In this way, it was performed the adsorption assays between lignocresol and β-glucosidases from Thermotoga petrophila, belonging to the families GH1 and GH3, for the development of a lignocresol-enzyme complex. Our results show that lignocresol maintains greater adsorptive capacity for β-glucosidases than lignin. This capacity can be explained both by its great hydrophobicity and also by electrostatic characteristics. Therefore, all these results demonstrate good adsorption of the enzymes to the lignocresol, demonstrating great potential for enzymatic recycling.
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Lu X, Li C, Zhang S, Wang X, Zhang W, Wang S, Xia T. Enzymatic sugar production from elephant grass and reed straw through pretreatments and hydrolysis with addition of thioredoxin-His-S. BIOTECHNOLOGY FOR BIOFUELS 2019; 12:297. [PMID: 31890025 PMCID: PMC6933627 DOI: 10.1186/s13068-019-1629-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Accepted: 12/04/2019] [Indexed: 05/20/2023]
Abstract
BACKGROUND The bioconversion of lignocellulose to fermentable C5/C6-saccharides is composed of pretreatment and enzymatic hydrolysis. Lignin, as one of the main components, resists lignocellulose to be bio-digested. Alkali and organosolv treatments were reported to be able to delignify feedstocks and loose lignocellulose structure. In addition, the use of additives was an alternative way to block lignin and reduce the binding of cellulases to lignin during hydrolysis. However, the relatively high cost of these additives limits their commercial application. RESULTS This study explored the feasibility of using elephant grass (Pennisetum purpureum) and reed straw (Phragmites australis), both of which are important fibrous plants with high biomass, no-occupation of cultivated land, and soil phytoremediation, as feedstocks for bio-saccharification. Compared with typical agricultural residues, elephant grass and reed straw contained high contents of cellulose and hemicellulose. However, lignin droplets on the surface of elephant grass and the high lignin content in reed straw limited their hydrolysis performances. High hydrolysis yield was obtained for reed straw after organosolv and alkali pretreatments via increasing cellulose content and removing lignin. However, the hydrolysis of elephant grass was only enhanced by organosolv pretreatment. Further study showed that the addition of bovine serum albumin (BSA) or thioredoxin with His- and S-Tags (Trx-His-S) improved the hydrolysis of alkali-pretreated elephant grass. In particular, Trx-His-S was first used as an additive in lignocellulose saccharification. Its structural and catalytic properties were supposed to be beneficial for enzymatic hydrolysis. CONCLUSIONS Elephant grass and reed straw could be used as feedstocks for bioconversion. Organosolv and alkali pretreatments improved their enzymatic sugar production; however, the increase in hydrolysis yield of pretreated elephant grass was not as effective as that of reed straw. During the hydrolysis of alkali-pretreated elephant grass, Trx-His-S performed well as additive, and its structural and catalytic capability was beneficial for enzymatic hydrolysis.
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Affiliation(s)
- Xianqin Lu
- State Key Laboratory of Biobased Material and Green Papermaking, Qilu University of Technology, Jinan, 250353 Shandong People’s Republic of China
- School of Bioengineering, Qilu University of Technology, Jinan, 250353 Shandong People’s Republic of China
- Advanced Research Institute for Multidisciplinary Science, Qilu University of Technology, Jinan, 250353 Shandong People’s Republic of China
| | - Can Li
- State Key Laboratory of Biobased Material and Green Papermaking, Qilu University of Technology, Jinan, 250353 Shandong People’s Republic of China
- School of Bioengineering, Qilu University of Technology, Jinan, 250353 Shandong People’s Republic of China
| | - Shengkui Zhang
- State Key Laboratory of Biobased Material and Green Papermaking, Qilu University of Technology, Jinan, 250353 Shandong People’s Republic of China
- School of Bioengineering, Qilu University of Technology, Jinan, 250353 Shandong People’s Republic of China
| | - Xiaohan Wang
- State Key Laboratory of Biobased Material and Green Papermaking, Qilu University of Technology, Jinan, 250353 Shandong People’s Republic of China
- School of Bioengineering, Qilu University of Technology, Jinan, 250353 Shandong People’s Republic of China
| | - Wenqing Zhang
- State Key Laboratory of Biobased Material and Green Papermaking, Qilu University of Technology, Jinan, 250353 Shandong People’s Republic of China
- School of Bioengineering, Qilu University of Technology, Jinan, 250353 Shandong People’s Republic of China
| | - Shouguo Wang
- Advanced Research Institute for Multidisciplinary Science, Qilu University of Technology, Jinan, 250353 Shandong People’s Republic of China
| | - Tao Xia
- State Key Laboratory of Biobased Material and Green Papermaking, Qilu University of Technology, Jinan, 250353 Shandong People’s Republic of China
- School of Bioengineering, Qilu University of Technology, Jinan, 250353 Shandong People’s Republic of China
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Karkehabadi S, Hansson H, Mikkelsen NE, Kim S, Kaper T, Sandgren M, Gudmundsson M. Structural studies of a glycoside hydrolase family 3 β-glucosidase from the model fungus Neurospora crassa. Acta Crystallogr F Struct Biol Commun 2018; 74:787-796. [PMID: 30511673 PMCID: PMC6277957 DOI: 10.1107/s2053230x18015662] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Accepted: 11/05/2018] [Indexed: 11/29/2022] Open
Abstract
The glycoside hydrolase family 3 (GH3) β-glucosidases are a structurally diverse family of enzymes. Cel3A from Neurospora crassa (NcCel3A) belongs to a subfamily of key enzymes that are crucial for industrial biomass degradation. β-Glucosidases hydrolyse the β-1,4 bond at the nonreducing end of cellodextrins. The hydrolysis of cellobiose is of special importance as its accumulation inhibits other cellulases acting on crystalline cellulose. Here, the crystal structure of the biologically relevant dimeric form of NcCel3A is reported. The structure has been refined to 2.25 Å resolution, with an Rcryst and Rfree of 0.18 and 0.22, respectively. NcCel3A is an extensively N-glycosylated glycoprotein that shares 46% sequence identity with Hypocrea jecorina Cel3A, the structure of which has recently been published, and 61% sequence identity with the thermophilic β-glucosidase from Rasamsonia emersonii. NcCel3A is a three-domain protein with a number of extended loops that deepen the active-site cleft of the enzyme. These structures characterize this subfamily of GH3 β-glucosidases and account for the high cellobiose specificity of this subfamily.
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Affiliation(s)
- Saeid Karkehabadi
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, PO Box 7015, SE-750 07 Uppsala, Sweden
| | - Henrik Hansson
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, PO Box 7015, SE-750 07 Uppsala, Sweden
| | - Nils Egil Mikkelsen
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, PO Box 7015, SE-750 07 Uppsala, Sweden
| | - Steve Kim
- DuPont Industrial Biosciences, 925 Page Mill Road, Palo Alto, CA 94304, USA
| | - Thijs Kaper
- DuPont Industrial Biosciences, 925 Page Mill Road, Palo Alto, CA 94304, USA
| | - Mats Sandgren
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, PO Box 7015, SE-750 07 Uppsala, Sweden
| | - Mikael Gudmundsson
- Department of Molecular Sciences, Swedish University of Agricultural Sciences, PO Box 7015, SE-750 07 Uppsala, Sweden
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Lu X, Feng X, Li X, Zhao J. The adsorption properties of endoglucanase to lignin and their impact on hydrolysis. BIORESOURCE TECHNOLOGY 2018; 267:110-116. [PMID: 30014989 DOI: 10.1016/j.biortech.2018.06.031] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2018] [Revised: 06/10/2018] [Accepted: 06/12/2018] [Indexed: 06/08/2023]
Abstract
Nonproductive adsorption of cellulase to lignin dramatically influenced the hydrolysis efficiency of lignocellulose. By comparing the adsorption behaviors of CBH and EG, we found that the adsorption of EG to lignin showed lower adsorption velocity and capacity versus CBH. During the adsorption of EG to lignin, carbohydrate binding domain (CBM) and catalytic domain (CD) both played an important role by a two-step adsorption process, in which CD slowly bond on lignin and developed stronger interaction with lignin. The optimal binding position of EG on lignin was consistent with that on polysaccharide located in the open catalytic tunnel. So, the adsorption of EG to lignin not only limited the movement of enzyme, but also restricted the catalytic ability of enzyme, which dramatically influenced enzymatic hydrolysis. Increasing the proportion of EG in cellulase cocktails or engineering "weak lignin adsorbed" EG was necessary to relieve the influence of lignin adsorption on hydrolysis.
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Affiliation(s)
- Xianqin Lu
- State Key Laboratory of Microbial Technology, Shandong University, No. 72, Binhai Road, Qingdao 266237, PR China
| | - Xiaoting Feng
- State Key Laboratory of Microbial Technology, Shandong University, No. 72, Binhai Road, Qingdao 266237, PR China
| | - Xuezhi Li
- State Key Laboratory of Microbial Technology, Shandong University, No. 72, Binhai Road, Qingdao 266237, PR China
| | - Jian Zhao
- State Key Laboratory of Microbial Technology, Shandong University, No. 72, Binhai Road, Qingdao 266237, PR China.
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36
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Nanoimmobilization of β-glucosidase onto hydroxyapatite. Int J Biol Macromol 2018; 119:1042-1051. [DOI: 10.1016/j.ijbiomac.2018.08.042] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Revised: 08/03/2018] [Accepted: 08/08/2018] [Indexed: 11/19/2022]
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Lu X, Feng X, Li X, Zhao J. Binding and hydrolysis properties of engineered cellobiohydrolases and endoglucanases. BIORESOURCE TECHNOLOGY 2018; 267:235-241. [PMID: 30025319 DOI: 10.1016/j.biortech.2018.06.047] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2018] [Revised: 06/14/2018] [Accepted: 06/17/2018] [Indexed: 05/03/2023]
Abstract
Because cellulase was the main enzyme used in bioconversion of lignocellulose, it was a valid way to reduce the hydrolysis cost by increasing the adsorption and hydrolysis efficiency of cellulase. In this study, modified cellobiohydrolases (CBHs) and endoglucanases (EGs) were constructed. Two engineered cellulases CBH-TrCBMV27E,P30D,Link1 and EG-TrCBMV27E,P30D,Link1 well-performed during hydrolysis. Compared to wild-type enzymes, EG-TrCBMV27E,P30D,Link1 had relatively less adsorption ability to lignin and greater affinity to cellulose, especially Avicel. However, for CBH-TrCBMV27E,P30D,Link1, the hydrolysis manner was changed and in favor to hydrolysis process, although the adsorption properties were unexpected. It suggested that various binding conformations of polysaccharide on CBMs hypothetically resulted in different functions of CBMs, including binding ability, processive and digestive properties on fiber surface. Fusion of T. r-CBMV27E,P30D,Link1 to cellulase, both CBH and EG, gave the destruction ability of enzyme and increased the accessible surface of substrate to cellulase, enhanced the adsorption and hydrolysis efficiency of cellulase.
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Affiliation(s)
- Xianqin Lu
- State Key Laboratory of Microbial Technology, Shandong University, No. 72, Binhai Road, Qingdao 266237, PR China
| | - Xiaoting Feng
- State Key Laboratory of Microbial Technology, Shandong University, No. 72, Binhai Road, Qingdao 266237, PR China
| | - Xuezhi Li
- State Key Laboratory of Microbial Technology, Shandong University, No. 72, Binhai Road, Qingdao 266237, PR China
| | - Jian Zhao
- State Key Laboratory of Microbial Technology, Shandong University, No. 72, Binhai Road, Qingdao 266237, PR China.
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Qu W, Lin D, Zhang Z, Di W, Gao B, Zeng R. Metagenomics Investigation of Agarlytic Genes and Genomes in Mangrove Sediments in China: A Potential Repertory for Carbohydrate-Active Enzymes. Front Microbiol 2018; 9:1864. [PMID: 30177916 PMCID: PMC6109693 DOI: 10.3389/fmicb.2018.01864] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Accepted: 07/25/2018] [Indexed: 12/31/2022] Open
Abstract
Monosaccharides and oligosaccharides produced by agarose degradation exhibit potential in the fields of bioenergy, medicine, and cosmetics. Mangrove sediments (MGSs) provide a special environment to enrich enzymes for agarose degradation. However, representative investigations of the agarlytic genes in MGSs have been rarely reported. In this study, agarlytic genes in MGSs were researched in detail from the aspects of diversity, abundance, activity, and location through deep metagenomics sequencing. Functional genes in MGSs were usually incomplete but were shown as results, which could cause virtually high number of results in previous studies because multiple fragmented sequences could originate from the same genes. In our work, only complete and nonredundant (CNR) genes were analyzed to avoid virtually high amount of the results. The number of CNR agarlytic genes in our datasets was significantly higher than that in the datasets of previous studies. Twenty-one recombinant agarases with agarose-degrading activity were detected using heterologous expression based on numerous complete open-reading frames, which are rarely obtained in metagenomics sequencing of samples with complex microbial communities, such as MGSs. Aga2, which had the highest crude enzyme activity among the 21 recombinant agarases, was further purified and subjected to enzymatic characterization. With its high agarose-degrading activity, resistance to temperature changes and chemical agents, Aga2 could be a suitable option for industrial production. The agarase ratio with signal peptides to that without signal peptides in our MGS datasets was lower than that of other reported agarases. Six draft genomes, namely, Clusters 1-6, were recovered from the datasets. The taxonomic annotation of these genomes revealed that Clusters 1, 3, 5, and 6 were annotated as Desulfuromonas sp., Treponema sp., Ignavibacteriales spp., and Polyangiaceae spp., respectively. Meanwhile, Clusters 2 and 4 were potential new species. All these genomes were first reported and found to have abilities of degrading various important polysaccharides. The metabolic pathway of agarose in Cluster 4 was also speculated. Our results showed the capacity and activity of agarases in the MGS microbiome, and MGSs exert potential as a repertory for mining not only agarlytic genes but also almost all genes of the carbohydrate-active enzyme family.
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Affiliation(s)
- Wu Qu
- School of Life Sciences, Xiamen University, Xiamen, China
| | - Dan Lin
- Novogene Bioinformatics Technology Co. Ltd., Tianjin, China
| | - Zhouhao Zhang
- Novogene Bioinformatics Technology Co. Ltd., Tianjin, China
| | - Wenjie Di
- Key Laboratory of Marine Genetic Resources, Third Institute of Oceanography, State Oceanic Administration, Xiamen, China
| | - Boliang Gao
- School of Life Sciences, Xiamen University, Xiamen, China
| | - Runying Zeng
- Key Laboratory of Marine Genetic Resources, Third Institute of Oceanography, State Oceanic Administration, Xiamen, China.,Key Laboratory of Marine Genetic Resources, Xiamen, China
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Structural and biochemical characterization of a GH3 β-glucosidase from the probiotic bacteria Bifidobacterium adolescentis. Biochimie 2018; 148:107-115. [DOI: 10.1016/j.biochi.2018.03.007] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Accepted: 03/13/2018] [Indexed: 11/20/2022]
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40
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Nishida VS, de Oliveira RF, Brugnari T, Correa RCG, Peralta RA, Castoldi R, de Souza CG, Bracht A, Peralta RM. Immobilization of Aspergillus awamori β-glucosidase on commercial gelatin: An inexpensive and efficient process. Int J Biol Macromol 2018; 111:1206-1213. [DOI: 10.1016/j.ijbiomac.2018.01.146] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2017] [Revised: 01/12/2018] [Accepted: 01/21/2018] [Indexed: 10/18/2022]
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41
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Gao J, Qian Y, Wang Y, Qu Y, Zhong Y. Production of the versatile cellulase for cellulose bioconversion and cellulase inducer synthesis by genetic improvement of Trichoderma reesei. BIOTECHNOLOGY FOR BIOFUELS 2017; 10:272. [PMID: 29167702 PMCID: PMC5688634 DOI: 10.1186/s13068-017-0963-1] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Accepted: 11/07/2017] [Indexed: 05/05/2023]
Abstract
BACKGROUND The enzymes for efficient hydrolysis of lignocellulosic biomass are a major factor in the development of an economically feasible cellulose bioconversion process. Up to now, low hydrolysis efficiency and high production cost of cellulases remain the significant hurdles in this process. The aim of the present study was to develop a versatile cellulase system with the enhanced hydrolytic efficiency and the ability to synthesize powerful inducers by genetically engineering Trichoderma reesei. RESULTS In our study, we employed a systematic genetic strategy to construct the carbon catabolite-derepressed strain T. reesei SCB18 to produce the cellulase complex that exhibited a strong cellulolytic capacity for biomass saccharification and an extraordinary high β-glucosidase (BGL) activity for cellulase-inducing disaccharides synthesis. We first identified the hypercellulolytic and uracil auxotrophic strain T. reesei SP4 as carbon catabolite repressed, and then deleted the carbon catabolite repressor gene cre1 in the genome. We found that the deletion of cre1 with the selectable marker pyrG led to a 72.6% increase in total cellulase activity, but a slight reduction in saccharification efficiency. To facilitate the following genetic modification, the marker pyrG was successfully removed by homologous recombination based on resistance to 5-FOA. Furthermore, the Aspergillus niger BGLA-encoding gene bglA was overexpressed, and the generated strain T. reesei SCB18 exhibited a 29.8% increase in total cellulase activity and a 51.3-fold enhancement in BGL activity (up to 103.9 IU/mL). We observed that the cellulase system of SCB18 showed significantly higher saccharification efficiency toward differently pretreated corncob residues than the control strains SDC11 and SP4. Moreover, the crude enzyme preparation from SCB18 with high BGL activity possessed strong transglycosylation ability to synthesize β-disaccharides from glucose. The transglycosylation product was finally utilized as the inducer for cellulase production, which provided a 63.0% increase in total cellulase activity compared to the frequently used soluble inducer, lactose. CONCLUSIONS In summary, we constructed a versatile cellulase system in T. reesei for efficient biomass saccharification and powerful cellulase inducer synthesis by combinational genetic manipulation of three distinct types of genes to achieve the customized cellulase production, thus providing a viable strategy for further strain improvement to reduce the cost of biomass-based biofuel production.
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Affiliation(s)
- Jia Gao
- State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University, Jinan, 250100 People’s Republic of China
| | - Yuanchao Qian
- State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University, Jinan, 250100 People’s Republic of China
| | - Yifan Wang
- State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University, Jinan, 250100 People’s Republic of China
| | - Yinbo Qu
- State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University, Jinan, 250100 People’s Republic of China
| | - Yaohua Zhong
- State Key Laboratory of Microbial Technology, School of Life Sciences, Shandong University, Jinan, 250100 People’s Republic of China
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42
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Homogenization of food samples for gamma spectrometry using tetramethylammonium hydroxide and enzymatic digestion. J Radioanal Nucl Chem 2017. [DOI: 10.1007/s10967-017-5434-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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43
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Inactivation kinetics and conformation change of Hypocrea orientalis β-glucosidase with guanidine hydrochloride. J Biosci Bioeng 2017; 124:143-149. [DOI: 10.1016/j.jbiosc.2017.03.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2016] [Accepted: 03/08/2017] [Indexed: 01/05/2023]
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Kellock M, Rahikainen J, Marjamaa K, Kruus K. Lignin-derived inhibition of monocomponent cellulases and a xylanase in the hydrolysis of lignocellulosics. BIORESOURCE TECHNOLOGY 2017; 232:183-191. [PMID: 28231536 DOI: 10.1016/j.biortech.2017.01.072] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2016] [Revised: 01/20/2017] [Accepted: 01/21/2017] [Indexed: 05/03/2023]
Abstract
Non-productive enzyme binding onto lignin is the major inhibitory mechanism, which reduces hydrolysis rates and yields and prevents efficient enzyme recycling in the hydrolysis of lignocellulosics. The detailed mechanisms of binding are still poorly understood. Enzyme-lignin interactions were investigated by comparing the structural properties and binding behaviour of fungal monocomponent enzymes, cellobiohydrolases TrCel7A and TrCel6A, endoglucanases TrCel7B and TrCel5A, a xylanase TrXyn11 and a β-glucosidase AnCel3A, onto lignins isolated from steam pretreated spruce and wheat straw. The enzymes exhibited decreasing affinity onto lignin model films in the following order: TrCel7B>TrCel6A>TrCel5A>AnCel3A>TrCel7A>TrXyn11. As analysed in Avicel hydrolysis, TrCel6A and TrCel7B were most inhibited by lignin isolated from pretreated spruce. This could be partially explained by adsorption of the enzyme onto the lignin surface. Enzyme properties, such as enzyme surface charge, thermal stability or surface hydrophobicity could not alone explain the adsorption behaviour.
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Affiliation(s)
- Miriam Kellock
- VTT Technical Research Centre of Finland Ltd, P.O. Box 1000, 02044 VTT, Finland.
| | - Jenni Rahikainen
- VTT Technical Research Centre of Finland Ltd, P.O. Box 1000, 02044 VTT, Finland.
| | - Kaisa Marjamaa
- VTT Technical Research Centre of Finland Ltd, P.O. Box 1000, 02044 VTT, Finland.
| | - Kristiina Kruus
- VTT Technical Research Centre of Finland Ltd, P.O. Box 1000, 02044 VTT, Finland.
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Characterization of four endophytic fungi as potential consolidated bioprocessing hosts for conversion of lignocellulose into advanced biofuels. Appl Microbiol Biotechnol 2017; 101:2603-2618. [PMID: 28078400 DOI: 10.1007/s00253-017-8091-1] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Revised: 12/13/2016] [Accepted: 12/21/2016] [Indexed: 10/20/2022]
Abstract
Recently, several endophytic fungi have been demonstrated to produce volatile organic compounds (VOCs) with properties similar to fossil fuels, called "mycodiesel," while growing on lignocellulosic plant and agricultural residues. The fact that endophytes are plant symbionts suggests that some may be able to produce lignocellulolytic enzymes, making them capable of both deconstructing lignocellulose and converting it into mycodiesel, two properties that indicate that these strains may be useful consolidated bioprocessing (CBP) hosts for the biofuel production. In this study, four endophytes Hypoxylon sp. CI4A, Hypoxylon sp. EC38, Hypoxylon sp. CO27, and Daldinia eschscholzii EC12 were selected and evaluated for their CBP potential. Analysis of their genomes indicates that these endophytes have a rich reservoir of biomass-deconstructing carbohydrate-active enzymes (CAZys), which includes enzymes active on both polysaccharides and lignin, as well as terpene synthases (TPSs), enzymes that may produce fuel-like molecules, suggesting that they do indeed have CBP potential. GC-MS analyses of their VOCs when grown on four representative lignocellulosic feedstocks revealed that these endophytes produce a wide spectrum of hydrocarbons, the majority of which are monoterpenes and sesquiterpenes, including some known biofuel candidates. Analysis of their cellulase activity when grown under the same conditions revealed that these endophytes actively produce endoglucanases, exoglucanases, and β-glucosidases. The richness of CAZymes as well as terpene synthases identified in these four endophytic fungi suggests that they are great candidates to pursue for development into platform CBP organisms.
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46
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Tu T, Li Y, Su X, Meng K, Ma R, Wang Y, Yao B, Lin Z, Luo H. Probing the role of cation-π interaction in the thermotolerance and catalytic performance of endo-polygalacturonases. Sci Rep 2016; 6:38413. [PMID: 27929074 PMCID: PMC5143973 DOI: 10.1038/srep38413] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Accepted: 11/09/2016] [Indexed: 02/06/2023] Open
Abstract
Understanding the dynamics of the key pectinase, polygalacturonase, and improving its thermotolerance and catalytic efficiency are of importance for the cost-competitive bioconversion of pectic materials. By combining structure analysis and molecular dynamics (MD) simulations, eight mutagenesis sites having the potential to form cation-π interactions were identified in the widely used fungal endo-polygalacturonase PG63. In comparison to the wild-type, three single mutants H58Y, T71Y and T304Y showed improved thermostability (the apparent Tms increased by 0.6-3.9 °C) and catalytic efficiency (by up to 32-fold). Chromatogram analysis of the hydrolysis products indicated that a larger amount of shorter sugars were released from the polygalacturonic acid by these three mutants than by the wild-type. MD analysis of the enzyme-substrate complexes illustrated that the mutants with introduced cation-π interaction have modified conformations of catalytic crevice, which provide an enviable environment for the catalytic process. Moreover, the lower plasticity of T3 loop 2 at the edge of the subsite tunnel appears to recruit the reducing ends of oligogalacturonide into the active site tunnel and initiates new hydrolysis reactions. This study demonstrates the importance of cation-π interaction in protein conformation and provides a realistic strategy to enhance the thermotolerance and catalytic performance of endo-polygalacturonases.
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Affiliation(s)
- Tao Tu
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, No. 12 Zhongguancun South Street, Beijing 100081, P. R. China
| | - Yeqing Li
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, No. 12 Zhongguancun South Street, Beijing 100081, P. R. China
| | - Xiaoyun Su
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, No. 12 Zhongguancun South Street, Beijing 100081, P. R. China
| | - Kun Meng
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, No. 12 Zhongguancun South Street, Beijing 100081, P. R. China
| | - Rui Ma
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, No. 12 Zhongguancun South Street, Beijing 100081, P. R. China
| | - Yuan Wang
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, No. 12 Zhongguancun South Street, Beijing 100081, P. R. China
| | - Bin Yao
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, No. 12 Zhongguancun South Street, Beijing 100081, P. R. China
| | - Zhemin Lin
- Institute of Animal Science and Veterinary Medicine, Hainan Academy of Agricultural Sciences, Haikou 571100, P. R. China
| | - Huiying Luo
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, No. 12 Zhongguancun South Street, Beijing 100081, P. R. China
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Albuquerque ED, Torres FAG, Fernandes AAR, Fernandes PM. Combined effects of high hydrostatic pressure and specific fungal cellulase improve coconut husk hydrolysis. Process Biochem 2016. [DOI: 10.1016/j.procbio.2016.07.010] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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48
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Yamaguchi A, Isozaki K, Nakamura M, Takaya H, Watanabe T. Discovery of 12-mer peptides that bind to wood lignin. Sci Rep 2016; 6:21833. [PMID: 26903196 PMCID: PMC4794044 DOI: 10.1038/srep21833] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2015] [Accepted: 02/02/2016] [Indexed: 11/09/2022] Open
Abstract
Lignin, an abundant terrestrial polymer, is the only large-volume renewable feedstock composed of an aromatic skeleton. Lignin has been used mostly as an energy source during paper production; however, recent interest in replacing fossil fuels with renewable resources has highlighted its potential value in providing aromatic chemicals. Highly selective degradation of lignin is pivotal for industrial production of paper, biofuels, chemicals, and materials. However, few studies have examined natural and synthetic molecular components recognizing the heterogeneous aromatic polymer. Here, we report the first identification of lignin-binding peptides possessing characteristic sequences using a phage display technique. The consensus sequence HFPSP was found in several lignin-binding peptides, and the outer amino acid sequence affected the binding affinity of the peptides. Substitution of phenylalanine7 with Ile in the lignin-binding peptide C416 (HFPSPIFQRHSH) decreased the affinity of the peptide for softwood lignin without changing its affinity for hardwood lignin, indicating that C416 recognised structural differences between the lignins. Circular dichroism spectroscopy demonstrated that this peptide adopted a highly flexible random coil structure, allowing key residues to be appropriately arranged in relation to the binding site in lignin. These results provide a useful platform for designing synthetic and biological catalysts selectively bind to lignin.
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Affiliation(s)
- Asako Yamaguchi
- Research Institute for Sustainable Humanosphere, Kyoto University, Gokasho Uji, Kyoto 611-0011, Japan
| | - Katsuhiro Isozaki
- Institute for Chemical Research, Kyoto University, Gokasho Uji, Kyoto 611-0011, Japan
| | - Masaharu Nakamura
- Institute for Chemical Research, Kyoto University, Gokasho Uji, Kyoto 611-0011, Japan
| | - Hikaru Takaya
- Institute for Chemical Research, Kyoto University, Gokasho Uji, Kyoto 611-0011, Japan
| | - Takashi Watanabe
- Research Institute for Sustainable Humanosphere, Kyoto University, Gokasho Uji, Kyoto 611-0011, Japan
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Non-productive adsorption of bacterial β-glucosidases on lignins is electrostatically modulated and depends on the presence of fibronection type III-like domain. Enzyme Microb Technol 2016; 87-88:1-8. [PMID: 27178788 DOI: 10.1016/j.enzmictec.2016.02.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Revised: 02/11/2016] [Accepted: 02/12/2016] [Indexed: 01/09/2023]
Abstract
Non-productive adsorption of cellulases onto lignins is an important mechanism that negatively affects the enzymatic hydrolysis of lignocellulose biomass. Here, we examined the non-productive adsorption of two bacterial β-glucosidases (GH1 and GH3) on lignins. The results showed that β-glucosidases can adsorb to lignins through different mechanisms. GH1 β-glucosidase adsorption onto lignins was found to be strongly pH-dependent, suggesting that the adsorption is electrostatically modulated. For GH3 β-glucosidase, the results suggested that the fibronectin type III-like domain interacts with lignins through electrostatic and hydrophobic interactions that can partially, or completely, overcome repulsive electrostatic forces between the catalytic domain and lignins. Finally, the increase of temperature did not result in the increase of β-glucosidases adsorption, probably because there is no significant increase in hydrophobic regions in the β-glucosidases structures. The data provided here can be useful for biotechnological applications, especially in the field of plant structural polysaccharides conversion into bioenergy and bioproducts.
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50
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Agirre J, Ariza A, Offen WA, Turkenburg JP, Roberts SM, McNicholas S, Harris PV, McBrayer B, Dohnalek J, Cowtan KD, Davies GJ, Wilson KS. Three-dimensional structures of two heavily N-glycosylated Aspergillus sp. family GH3 β-D-glucosidases. Acta Crystallogr D Struct Biol 2016; 72:254-65. [PMID: 26894673 PMCID: PMC4756609 DOI: 10.1107/s2059798315024237] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2015] [Accepted: 12/16/2015] [Indexed: 01/25/2023] Open
Abstract
The industrial conversion of cellulosic plant biomass into useful products such as biofuels is a major societal goal. These technologies harness diverse plant degrading enzymes, classical exo- and endo-acting cellulases and, increasingly, cellulose-active lytic polysaccharide monooxygenases, to deconstruct the recalcitrant β-D-linked polysaccharide. A major drawback with this process is that the exo-acting cellobiohydrolases suffer from severe inhibition from their cellobiose product. β-D-Glucosidases are therefore important for liberating glucose from cellobiose and thereby relieving limiting product inhibition. Here, the three-dimensional structures of two industrially important family GH3 β-D-glucosidases from Aspergillus fumigatus and A. oryzae, solved by molecular replacement and refined at 1.95 Å resolution, are reported. Both enzymes, which share 78% sequence identity, display a three-domain structure with the catalytic domain at the interface, as originally shown for barley β-D-glucan exohydrolase, the first three-dimensional structure solved from glycoside hydrolase family GH3. Both enzymes show extensive N-glycosylation, with only a few external sites being truncated to a single GlcNAc molecule. Those glycans N-linked to the core of the structure are identified purely as high-mannose trees, and establish multiple hydrogen bonds between their sugar components and adjacent protein side chains. The extensive glycans pose special problems for crystallographic refinement, and new techniques and protocols were developed especially for this work. These protocols ensured that all of the D-pyranosides in the glycosylation trees were modelled in the preferred minimum-energy (4)C1 chair conformation and should be of general application to refinements of other crystal structures containing O- or N-glycosylation. The Aspergillus GH3 structures, in light of other recent three-dimensional structures, provide insight into fungal β-D-glucosidases and provide a platform on which to inform and inspire new generations of variant enzymes for industrial application.
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Affiliation(s)
- Jon Agirre
- York Structural Biology Laboratory, Department of Chemistry, The University of York, York YO10 5DD, England
| | - Antonio Ariza
- York Structural Biology Laboratory, Department of Chemistry, The University of York, York YO10 5DD, England
| | - Wendy A. Offen
- York Structural Biology Laboratory, Department of Chemistry, The University of York, York YO10 5DD, England
| | - Johan P. Turkenburg
- York Structural Biology Laboratory, Department of Chemistry, The University of York, York YO10 5DD, England
| | - Shirley M. Roberts
- York Structural Biology Laboratory, Department of Chemistry, The University of York, York YO10 5DD, England
| | - Stuart McNicholas
- York Structural Biology Laboratory, Department of Chemistry, The University of York, York YO10 5DD, England
| | | | | | - Jan Dohnalek
- York Structural Biology Laboratory, Department of Chemistry, The University of York, York YO10 5DD, England
| | - Kevin D. Cowtan
- York Structural Biology Laboratory, Department of Chemistry, The University of York, York YO10 5DD, England
| | - Gideon J. Davies
- York Structural Biology Laboratory, Department of Chemistry, The University of York, York YO10 5DD, England
| | - Keith S. Wilson
- York Structural Biology Laboratory, Department of Chemistry, The University of York, York YO10 5DD, England
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