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Dotsenko A, Sinelnikov I, Rozhkova A, Zorov I, Sinitsyn A. Flexibility of active center affects thermostability and activity of Penicillium canescens xylanase E. Biochimie 2024; 216:83-89. [PMID: 37820990 DOI: 10.1016/j.biochi.2023.10.004] [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: 06/22/2023] [Revised: 10/03/2023] [Accepted: 10/04/2023] [Indexed: 10/13/2023]
Abstract
Xylanases are used in several industrial applications, such as feed additives, the bleaching of pulp and paper, and the production of bread, food, and drinks. Xylanases are required to remain active after heat treatment at 80-90 °C for 30 s to several minutes due to the conditions of feed pelleting. Also, xylanases need to be active at 60-70 °C for several hours while bleaching of pulp and paper or manufacturing of bread, food, and drinks is performed. Xylanases of the glycoside hydrolase family GH10 are good candidates for application in such processes because of their high thermostability and, in particular, as feed additives because of their insensitivity to protein inhibitors in cereal feeds. In the study, the thermostability of GH10 xylanase E from Penicillium canescens was improved to reach a half-inactivation period of 2 min at 80 °C compared to 21 s for the wild-type enzyme (WT). Enzymatic activity was increased by 22-48 % at 40-70 °C, which improved the action of the enzyme as a feed additive in the gastric system of animals and during bleaching of pulp and paper. Molecular dynamics simulations demonstrated lower flexibility of the tertiary structure of the engineered enzyme at elevated temperatures compared to WT. The residues W113, Q116, W313, and W321 in the (-1) and (-2) subsites for the substrate binding were less flexible. In the simulations, the engineered enzyme had a comparable content of α-helixes, 310-helixes, β-sheets, and β-bridges as WT, but a lower content of coils and a higher content of β-turns.
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Affiliation(s)
- Anna Dotsenko
- Federal Research Centre «Fundamentals of Biotechnology», Russian Academy of Sciences, Moscow, 119071, Russia.
| | - Igor Sinelnikov
- Federal Research Centre «Fundamentals of Biotechnology», Russian Academy of Sciences, Moscow, 119071, Russia.
| | - Aleksandra Rozhkova
- Federal Research Centre «Fundamentals of Biotechnology», Russian Academy of Sciences, Moscow, 119071, Russia.
| | - Ivan Zorov
- Federal Research Centre «Fundamentals of Biotechnology», Russian Academy of Sciences, Moscow, 119071, Russia; Department of Chemistry, M.V. Lomonosov Moscow State University, Moscow, 119991, Russia.
| | - Arkady Sinitsyn
- Federal Research Centre «Fundamentals of Biotechnology», Russian Academy of Sciences, Moscow, 119071, Russia; Department of Chemistry, M.V. Lomonosov Moscow State University, Moscow, 119991, Russia.
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2
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Crosby JR, Laemthong T, Bing RG, Zhang K, Tanwee TNN, Lipscomb GL, Rodionov DA, Zhang Y, Adams MWW, Kelly RM. Biochemical and Regulatory Analyses of Xylanolytic Regulons in Caldicellulosiruptor bescii Reveal Genus-Wide Features of Hemicellulose Utilization. Appl Environ Microbiol 2022; 88:e0130222. [PMID: 36218355 PMCID: PMC9642015 DOI: 10.1128/aem.01302-22] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Accepted: 09/19/2022] [Indexed: 11/20/2022] Open
Abstract
Caldicellulosiruptor species scavenge carbohydrates from runoff containing plant biomass that enters hot springs and from grasses that grow in more moderate parts of thermal features. While only a few Caldicellulosiruptor species can degrade cellulose, all known species are hemicellulolytic. The most well-characterized species, Caldicellulosiruptor bescii, decentralizes its hemicellulase inventory across five different genomic loci and two isolated genes. Transcriptomic analyses, comparative genomics, and enzymatic characterization were utilized to assign functional roles and determine the relative importance of its six putative endoxylanases (five glycoside hydrolase family 10 [GH10] enzymes and one GH11 enzyme) and two putative exoxylanases (one GH39 and one GH3) in C. bescii. Two genus-wide conserved xylanases, C. bescii XynA (GH10) and C. bescii Xyl3A (GH3), had the highest levels of sugar release on oat spelt xylan, were in the top 10% of all genes transcribed by C. bescii, and were highly induced on xylan compared to cellulose. This indicates that a minimal set of enzymes are used to drive xylan degradation in the genus Caldicellulosiruptor, complemented by hemicellulolytic inventories that are tuned to specific forms of hemicellulose in available plant biomasses. To this point, synergism studies revealed that the pairing of specific GH family proteins (GH3, -11, and -39) with C. bescii GH10 proteins released more sugar in vitro than mixtures containing five different GH10 proteins. Overall, this work demonstrates the essential requirements for Caldicellulosiruptor to degrade various forms of xylan and the differences in species genomic inventories that are tuned for survival in unique biotopes with variable lignocellulosic substrates. IMPORTANCE Microbial deconstruction of lignocellulose for the production of biofuels and chemicals requires the hydrolysis of heterogeneous hemicelluloses to access the microcrystalline cellulose portion. This work extends previous in vivo and in vitro efforts to characterize hemicellulose utilization by integrating genomic reconstruction, transcriptomic data, operon structures, and biochemical characteristics of key enzymes to understand the deployment and functionality of hemicellulases by the extreme thermophile Caldicellulosiruptor bescii. Furthermore, comparative genomics of the genus revealed both conserved and divergent mechanisms for hemicellulose utilization across the 15 sequenced species, thereby paving the way to connecting functional enzyme characterization with metabolic engineering efforts to enhance lignocellulose conversion.
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Affiliation(s)
- James R. Crosby
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, North Carolina, USA
| | - Tunyaboon Laemthong
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, North Carolina, USA
| | - Ryan G. Bing
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, North Carolina, USA
| | - Ke Zhang
- Department of Cell and Molecular Biology, College of the Environmental and Life Sciences, University of Rhode Island, Kinston, Rhode Island, USA
| | - Tania N. N. Tanwee
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia, USA
| | - Gina L. Lipscomb
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia, USA
| | - Dmitry A. Rodionov
- Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California, USA
| | - Ying Zhang
- Department of Cell and Molecular Biology, College of the Environmental and Life Sciences, University of Rhode Island, Kinston, Rhode Island, USA
| | - Michael W. W. Adams
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia, USA
| | - Robert M. Kelly
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, North Carolina, USA
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Marchisio F, Di Nardo L, Val DS, Cerminati S, Espariz M, Rasia RM, Menzella HG, Castelli ME. Characterization of a novel thermostable phospholipase C from T. kodakarensis suitable for oil degumming. Appl Microbiol Biotechnol 2022; 106:5081-5091. [PMID: 35854045 DOI: 10.1007/s00253-022-12081-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Revised: 07/09/2022] [Accepted: 07/13/2022] [Indexed: 11/24/2022]
Abstract
The implementation of cleaner technologies that minimize environmental pollution caused by conventional industrial processes is an increasing global trend. Hence, traditionally used chemicals have been replaced by novel enzymatic alternatives in a wide variety of industrial-scale processes. Enzymatic oil degumming, the first step of the oil refining process, exploits the conversion catalyzed by phospholipases to remove vegetable crude oils' phospholipids. This enzymatic method reduces the gums' volume and increases the overall oil yield. A thermostable phospholipase would be highly advantageous for industrial oil degumming as oil treatment at higher temperatures would save energy and increase the recovery of oil by facilitating the mixing and gums removal. A thermostable phosphatidylcholine (PC) (and phosphatidylethanolamine (PE))-specific phospholipase C from Thermococcus kodakarensis (TkPLC) was studied and completely removed PC and PE from crude soybean oil at 80 °C. Due to these characteristics, TkPLC is an interesting promising candidate for industrial-scale enzymatic oil degumming at high temperatures. KEY POINTS: • A thermostable phospholipase C from T. kodakarensis (TkPLC) has been identified. • TkPLC was recombinantly produced in Pichia pastoris and successfully purified. • TkPLC completely hydrolyzed PC and PE in soybean oil degumming assays at 80 °C.
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Affiliation(s)
- Fiorela Marchisio
- Instituto de Procesos Biotecnológicos Y Químicos (IPROBYQ), Facultad de Ciencias, Bioquímicas Y Farmacéuticas, Universidad Nacional de Rosario (UNR), CONICET. Mitre 1998, S2000FWF, Rosario, Argentina
| | - Luisina Di Nardo
- Facultad de Ciencias, Bioquímicas Y Farmacéuticas, Instituto de Biología Celular Y Molecular de Rosario (IBR), Universidad Nacional de Rosario (UNR), CONICET. Ocampo Y Esmeralda S/N, 2000, Rosario, Argentina
| | - Diego Sebastián Val
- Instituto de Procesos Biotecnológicos Y Químicos (IPROBYQ), Facultad de Ciencias, Bioquímicas Y Farmacéuticas, Universidad Nacional de Rosario (UNR), CONICET. Mitre 1998, S2000FWF, Rosario, Argentina
| | - Sebastián Cerminati
- Instituto de Procesos Biotecnológicos Y Químicos (IPROBYQ), Facultad de Ciencias, Bioquímicas Y Farmacéuticas, Universidad Nacional de Rosario (UNR), CONICET. Mitre 1998, S2000FWF, Rosario, Argentina
| | - Martín Espariz
- Instituto de Procesos Biotecnológicos Y Químicos (IPROBYQ), Facultad de Ciencias, Bioquímicas Y Farmacéuticas, Universidad Nacional de Rosario (UNR), CONICET. Mitre 1998, S2000FWF, Rosario, Argentina.,Área Estadística Y Procesamiento de Datos, Departamento de Matemática Y Estadística, Facultad de Ciencias Bioquímicas Y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Argentina
| | - Rodolfo Maximiliano Rasia
- Facultad de Ciencias, Bioquímicas Y Farmacéuticas, Instituto de Biología Celular Y Molecular de Rosario (IBR), Universidad Nacional de Rosario (UNR), CONICET. Ocampo Y Esmeralda S/N, 2000, Rosario, Argentina.,Plataforma Argentina de Biología Estructural Y Metabolómica (PLABEM - CONICET), Ocampo y Esmeralda s/n, 2000, Rosario, Argentina
| | - Hugo Gabriel Menzella
- Instituto de Procesos Biotecnológicos Y Químicos (IPROBYQ), Facultad de Ciencias, Bioquímicas Y Farmacéuticas, Universidad Nacional de Rosario (UNR), CONICET. Mitre 1998, S2000FWF, Rosario, Argentina
| | - María Eugenia Castelli
- Instituto de Procesos Biotecnológicos Y Químicos (IPROBYQ), Facultad de Ciencias, Bioquímicas Y Farmacéuticas, Universidad Nacional de Rosario (UNR), CONICET. Mitre 1998, S2000FWF, Rosario, Argentina.
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Hu D, Zhao X. Characterization of a New Xylanase Found in the Rumen Metagenome and Its Effects on the Hydrolysis of Wheat. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2022; 70:6493-6502. [PMID: 35583133 DOI: 10.1021/acs.jafc.2c00827] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Wheat is the main ingredient of poultry diet, but its xylan has an adverse impact on poultry production. A novel xylanase from beef cattle rumen metagenome (RuXyn) and its effect on the wheat hydrolysis were investigated in the present study. The RuXyn coded for 377 amino acids and exhibited low identity (<40%) to previously reported proteins. The RuXyn was heterologously expressed in Escherichia coli and showed maximum activity at pH 6.0 and 40 °C. The activity of RuXyn could be increased by 79.8 and 36.0% in the presence of Ca2+ and Tween 20, respectively. The soluble xylan and insoluble xylan in wheat could be effectively degraded by RuXyn and xylooligosaccharides produced accounting for more than 80% of the products. This study demonstrates that RuXyn has substantial potential to improve the application of wheat in poultry production by degrading wheat xylan and the accompanying xylooligosaccharides produced.
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Affiliation(s)
- Die Hu
- Jiangxi Province Key Laboratory of Animal Nutrition/Engineering Research Center of Feed Development, College of Animal Science and Technology, Jiangxi Agricultural University, Nanchang, Jiangxi 330045, China
| | - Xianghui Zhao
- Jiangxi Province Key Laboratory of Animal Nutrition/Engineering Research Center of Feed Development, College of Animal Science and Technology, Jiangxi Agricultural University, Nanchang, Jiangxi 330045, China
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5
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Le Y, Sun J. CRISPR/Cas genome editing systems in thermophiles: Current status, associated challenges, and future perspectives. ADVANCES IN APPLIED MICROBIOLOGY 2022; 118:1-30. [PMID: 35461662 DOI: 10.1016/bs.aambs.2022.02.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Thermophiles, offering an attractive and unique platform for a broad range of applications in biofuels and environment protections, have received a significant attention and growing interest from academy and industry. However, the exploration and exploitation of thermophilic organisms have been hampered by the lack of a powerful genome manipulation tool to improve production efficiency. At current, the clustered Regularly Interspaced Short Palindromic Repeat (CRISPR)/CRISPR associated (Cas) system has been successfully exploited as a competent, simplistic, and powerful tool for genome engineering both in eukaryotes and prokaryotes. Indeed, with the significant efforts made in recent years, some thermostable Cas9 proteins have been well identified and characterized and further, some thermostable Cas9-based editing tools have been successfully established in some representative obligate thermophiles. In this regard, we reviewed the current status and its progress in CRISPR/Cas-based genome editing system towards a variety of thermophilic organisms. Despite the potentials of these progresses, multiple factors/barriers still have to be overcome and optimized for improving its editing efficiency in thermophiles. Some insights into the roles of thermostable CRISPR/Cas technologies for the metabolic engineering of thermophiles as a thermophilic microbial cell factory were also fully analyzed and discussed.
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Affiliation(s)
- Yilin Le
- Biofuels institute, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, Jiangsu, PR China.
| | - Jianzhong Sun
- Biofuels institute, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, Jiangsu, PR China.
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6
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Gufe C, Ngenyoung A, Rattanarojpong T, Khunrae P. Investigation into the effects of CbXyn10C and Xyn11A on xylooligosaccharide profiles produced from sugarcane bagasse and rice straw and their impact on probiotic growth. BIORESOURCE TECHNOLOGY 2022; 344:126319. [PMID: 34775054 DOI: 10.1016/j.biortech.2021.126319] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Revised: 11/07/2021] [Accepted: 11/08/2021] [Indexed: 06/13/2023]
Abstract
This comparative study investigated the effects of CbXyn10C and Xyn11A on xylooligosaccharide profiles produced from sugarcane bagasse (SCB) and rice straw (RS) and their impact on probiotic growth. Generally, CbXyn10C produced more xylose and a higher total phenolic content than Xyn11A. Interestingly, XOS obtained from SCB with CbXyn10C contained significantly more gallic acid than that produced by Xn11A. All selected probiotics thrived in RS-derived XOS, regardless of the enzyme used. However, probiotics grew differently on SCB-derived XOS depending on the enzyme used. All probiotics thrived in Xyn11A-derived XOS from SCB. Only Lactobacillus plantarum thrived on CbXyn10C-derived XOS, while the other two were inhibited. Gallic acid in CbXyn10C-derived XOS from SCB has been linked to probiotic retardation, and gallic acid-enriched broth has been found to inhibit Bifidobacterium longum and Bacillus subtilis, but not L. plantarum. Consequently, the selection of enzymes and plant biomass is crucial for XOS properties and prebiotic effects.
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Affiliation(s)
- Claudious Gufe
- Department of Microbiology, Science Laboratory Building, Faculty of Science, King Mongkut's University of Technology Thonburi, Thailand
| | - Apichet Ngenyoung
- Department of Microbiology, Science Laboratory Building, Faculty of Science, King Mongkut's University of Technology Thonburi, Thailand
| | - Triwit Rattanarojpong
- Department of Microbiology, Science Laboratory Building, Faculty of Science, King Mongkut's University of Technology Thonburi, Thailand
| | - Pongsak Khunrae
- Department of Microbiology, Science Laboratory Building, Faculty of Science, King Mongkut's University of Technology Thonburi, Thailand.
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7
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Endo-xylanases from Cohnella sp. AR92 aimed at xylan and arabinoxylan conversion into value-added products. Appl Microbiol Biotechnol 2021; 105:6759-6778. [PMID: 34458936 DOI: 10.1007/s00253-021-11495-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Revised: 06/29/2021] [Accepted: 08/03/2021] [Indexed: 10/20/2022]
Abstract
The genus Cohnella belongs to a group of Gram-positive endospore-forming bacteria within the Paenibacillaceae family. Although most species were described as xylanolytic bacteria, the literature still lacks some key information regarding their repertoire of xylan-degrading enzymes. The whole genome sequence of an isolated xylan-degrading bacterium Cohnella sp. strain AR92 was found to contain five genes encoding putative endo-1,4-β-xylanases, of which four were cloned, expressed, and characterized to better understand the contribution of the individual endo-xylanases to the overall xylanolytic properties of strain AR92. Three of the enzymes, CoXyn10A, CoXyn10C, and CoXyn11A, were shown to be effective at hydrolyzing xylans-derived from agro-industrial, producing oligosaccharides with substrate conversion values of 32.5%, 24.7%, and 10.6%, respectively, using sugarcane bagasse glucuronoarabinoxylan and of 29.9%, 19.1%, and 8.0%, respectively, using wheat bran-derived arabinoxylan. The main reaction products from GH10 enzymes were xylobiose and xylotriose, whereas CoXyn11A produced mostly xylooligosaccharides (XOS) with 2 to 5 units of xylose, often substituted, resulting in potentially prebiotic arabinoxylooligosaccharides (AXOS). The endo-xylanases assay displayed operational features (temperature optima from 49.9 to 50.4 °C and pH optima from 6.01 to 6.31) fitting simultaneous xylan utilization. Homology modeling confirmed the typical folds of the GH10 and GH11 enzymes, substrate docking studies allowed the prediction of subsites (- 2 to + 1 in GH10 and - 3 to + 1 in GH11) and identification of residues involved in ligand interactions, supporting the experimental data. Overall, the Cohnella sp. AR92 endo-xylanases presented significant potential for enzymatic conversion of agro-industrial by-products into high-value products.Key points• Cohnella sp. AR92 genome encoded five potential endo-xylanases.• Cohnella sp. AR92 enzymes produced xylooligosaccharides from xylan, with high yields.• GH10 enzymes from Cohnella sp. AR92 are responsible for the production of X2 and X3 oligosaccharides.• GH11 from Cohnella sp. AR92 contributes to the overall xylan degradation by producing substituted oligosaccharides.
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8
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Xie W, Yu Q, Zhang R, Liu Y, Cao R, Wang S, Zhan R, Liu Z, Wang K, Wang C. Insights into the Catalytic Mechanism of a Novel XynA and Structure-Based Engineering for Improving Bifunctional Activities. Biochemistry 2021; 60:2071-2083. [PMID: 34156819 DOI: 10.1021/acs.biochem.1c00134] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Xylan and cellulose are the two major constituents of numerous types of lignocellulose. The bifunctional enzyme that exhibits xylanase/cellulase activity has attracted a great deal of attention in biofuel production. Previously, a thermostable GH10 family enzyme (XynA) from Bacillus sp. KW1 was found to degrade both xylan and cellulose. To improve bifunctional activity on the basis of structure, we first determined the crystal structure of XynA at 2.3 Å. Via molecular docking and activity assays, we revealed that Gln250 and His252 were indispensable to bifunctionality, because they could interact with two conserved catalytic residues, Glu182 and Glu280, while bringing the substrate close to the activity pocket. Then we used a structure-based engineering strategy to improve xylanase/cellulase activity. Although no mutants with increased bifunctional activity were obtained after much screening, we found the answer in the N-terminal 36-amino acid truncation of XynA. The activities of XynA_ΔN36 toward beechwood xylan, wheat arabinoxylan, filter paper, and barley β-glucan were significantly increased by 0.47-, 0.53-, 2.46-, and 1.04-fold, respectively. Furthermore, upon application, this truncation released more reducing sugars than the wild type in the degradation of pretreated corn stover and sugar cane bagasse. These results showed the detailed molecular mechanism of the GH10 family bifunctional endoxylanase/cellulase. The basis of these catalytic performances and the screened XynA_ΔN36 provide clues for the further use of XynA in industrial applications.
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Affiliation(s)
- Wei Xie
- Guangdong Key Laboratory for Translational Cancer Research of Chinese Medicine, Joint Laboratory for Translational Cancer Research of Chinese Medicine of the Ministry of Education of the People's Republic of China, International Institute for Translational Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong 510006, China
| | - Qi Yu
- Guangdong Key Laboratory for Translational Cancer Research of Chinese Medicine, Joint Laboratory for Translational Cancer Research of Chinese Medicine of the Ministry of Education of the People's Republic of China, International Institute for Translational Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong 510006, China
| | - Ruiqing Zhang
- Research Center of Chinese Herbal Resource Science and Engineering, Key Laboratory of Chinese Medicinal Resource from Lingnan (Guangzhou University of Chinese Medicine), Ministry of Education, Joint Laboratory of National Engineering Research Center for the Pharmaceutics of Traditional Chinese Medicines, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong 510006, China
| | - Yun Liu
- Research Center of Chinese Herbal Resource Science and Engineering, Key Laboratory of Chinese Medicinal Resource from Lingnan (Guangzhou University of Chinese Medicine), Ministry of Education, Joint Laboratory of National Engineering Research Center for the Pharmaceutics of Traditional Chinese Medicines, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong 510006, China
| | - Ruoting Cao
- Research Center of Chinese Herbal Resource Science and Engineering, Key Laboratory of Chinese Medicinal Resource from Lingnan (Guangzhou University of Chinese Medicine), Ministry of Education, Joint Laboratory of National Engineering Research Center for the Pharmaceutics of Traditional Chinese Medicines, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong 510006, China
| | - Sidi Wang
- College of Fundamental Medical Sciences, Guangzhou University of Chinese Medicine, Guangzhou 510006, China
| | - Ruoting Zhan
- Research Center of Chinese Herbal Resource Science and Engineering, Key Laboratory of Chinese Medicinal Resource from Lingnan (Guangzhou University of Chinese Medicine), Ministry of Education, Joint Laboratory of National Engineering Research Center for the Pharmaceutics of Traditional Chinese Medicines, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong 510006, China
| | - Zhongqiu Liu
- Guangdong Key Laboratory for Translational Cancer Research of Chinese Medicine, Joint Laboratory for Translational Cancer Research of Chinese Medicine of the Ministry of Education of the People's Republic of China, International Institute for Translational Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong 510006, China
| | - Kui Wang
- Research Center of Chinese Herbal Resource Science and Engineering, Key Laboratory of Chinese Medicinal Resource from Lingnan (Guangzhou University of Chinese Medicine), Ministry of Education, Joint Laboratory of National Engineering Research Center for the Pharmaceutics of Traditional Chinese Medicines, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong 510006, China
| | - Caiyan Wang
- Guangdong Key Laboratory for Translational Cancer Research of Chinese Medicine, Joint Laboratory for Translational Cancer Research of Chinese Medicine of the Ministry of Education of the People's Republic of China, International Institute for Translational Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong 510006, China
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9
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Li G, Zhou X, Li Z, Liu Y, Liu D, Miao Y, Wan Q, Zhang R. Significantly improving the thermostability of a hyperthermophilic GH10 family xylanase XynAF1 by semi-rational design. Appl Microbiol Biotechnol 2021; 105:4561-4576. [PMID: 34014347 DOI: 10.1007/s00253-021-11340-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2021] [Revised: 04/16/2021] [Accepted: 05/09/2021] [Indexed: 11/28/2022]
Abstract
Xylanases have a broad range of applications in industrial biotechnologies, which require the enzymes to resist the high-temperature environments. The majority of xylanases have maximum activity at moderate temperatures, which limited their potential applications in industries. In this study, a thermophilic GH10 family xylanase XynAF1 from the high-temperature composting strain Aspergillus fumigatus Z5 was characterized and engineered to further improve its thermostability. XynAF1 has the optimal reaction temperature of 90 °C. The crystal structure of XynAF1 was obtained by X-ray diffraction after heterologous expression, purification, and crystallization. The high-resolution X-ray crystallographic structure of the protein-product complex was obtained by soaking the apo-state crystal with xylotetraose. Structure analysis indicated that XynAF1 has a rigid skeleton, which helps to maintain the hyperthermophilic characteristic. The homologous structure analysis and the catalytic center mutant construction of XynAF1 indicated the conserved catalytic center contributed to the high optimum catalytic temperature. The amino acids in the surface of xylanase XynAF1 which might influence the enzyme thermostability were identified by the structure analysis. Combining the rational design with the saturation mutation at the high B-value regions, the integrative mutant XynAF1-AC with a 6-fold increase of thermostability was finally obtained. This study efficiently improved the thermostability of a GH10 family xylanase by semi-rational design, which provided a new biocatalyst for high-temperature biotechnological applications. KEY POINTS: • Obtained the crystal structure of GH10 family hyperthermophilic xylanase XynAF1. • Shed light on the understanding of the GH10 family xylanase thermophilic mechanism. • Constructed a 6-fold increased thermostability recombinant xylanase.
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Affiliation(s)
- Guangqi Li
- Key Laboratory of Microbial Resources Collection and Preservation, Ministry of Agriculture, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, 100081, People's Republic of China.,Jiangsu Provincial Key Lab for Organic Solid Waste Utilization, National Engineering Research Center for Organic-based Fertilizers, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
| | - Xuan Zhou
- National Agricultural Technology Extension and Service Center, Beijing, 100125, People's Republic of China
| | - Zhihong Li
- College of Science, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
| | - Yunpeng Liu
- Key Laboratory of Microbial Resources Collection and Preservation, Ministry of Agriculture, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, 100081, People's Republic of China
| | - Dongyang Liu
- Jiangsu Provincial Key Lab for Organic Solid Waste Utilization, National Engineering Research Center for Organic-based Fertilizers, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
| | - Youzhi Miao
- Jiangsu Provincial Key Lab for Organic Solid Waste Utilization, National Engineering Research Center for Organic-based Fertilizers, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
| | - Qun Wan
- College of Science, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China. .,The Key Laboratory of Plant Immunity, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China.
| | - Ruifu Zhang
- Key Laboratory of Microbial Resources Collection and Preservation, Ministry of Agriculture, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, 100081, People's Republic of China. .,Jiangsu Provincial Key Lab for Organic Solid Waste Utilization, National Engineering Research Center for Organic-based Fertilizers, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China.
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10
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Structural insights into xylanase mutant 254RL1 for improved activity and lower pH optimum. Enzyme Microb Technol 2021; 147:109786. [PMID: 33992408 DOI: 10.1016/j.enzmictec.2021.109786] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Revised: 03/16/2021] [Accepted: 03/17/2021] [Indexed: 11/24/2022]
Abstract
Xylanases degrade xylan to valuable end products. In our previous study, the alkaline xylanase S7-xyl from Bacillus halodurans S7 was engineered by rational design and the best mutant xylanase 254RL1 exhibited 3.4-fold improvements in specific activity at pH 9.0. Further research found that the enzyme activity at pH 6.0 was almost 2-fold than that at pH 9.0. To elucidate the reason of enhanced performance of 254RL1 at decreased pH optimum, we determined the X-ray crystal structure of 254RL1 at 2.21 Å resolution. The structural analysis revealed that the mutations enlarged the opening of the access tunnel and shortened the tunnel. Moreover, the mutations changed the hydrogen bond network around the catalytic residue and decreased the pKa value of acid-base catalyst E159 which reduced the pH optimum of the xylanase. The result provided the basis for the acid-alkaline engineering of the glycoside hydrolases.
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11
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Zhang C, Ding Y. Probing the Relation Between Community Evolution in Dynamic Residue Interaction Networks and Xylanase Thermostability. IEEE/ACM TRANSACTIONS ON COMPUTATIONAL BIOLOGY AND BIOINFORMATICS 2021; 18:686-696. [PMID: 31217124 DOI: 10.1109/tcbb.2019.2922906] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Residue-residue interactions are the basis of protein thermostability. The molecular conformations of Streptomyces lividans xylanase (xyna_strli) and Thermoascus aurantiacus xylanase (xyna_theau) at 300K, 325K and 350K were obtained by Molecular Dynamics (MD) simulations. Dynamic weighted residue interaction networks were constructed and the rigid-communities were detected using the ESPRA algorithm and the Evolving Graph+Fast-Newman algorithm. The residues in the rigid-communities are primarily located in loop2, short helixes α2', α3', α4' and helixes α3 and α4. Thus, the rigid-community is close to the N-terminus of xylanase, which is usually stabilized to increase thermostability using site-directed mutagenesis. The evolution of the rigid-community with increasing temperature shows a stable synergistic interaction between loop2, α2', α3' and α4' in xyna_theau. In particular, the short helixes α2' and α3' form a "thermo helix" to promote thermostability. In addition, tight global interactions between loop2, α2', α3', α3, α4' and α4 of xyna_theau are identified, consisting mainly of hydrogen bonds, van der Waals forces and π-π stacking. These residue interactions are more resistant to high temperatures than those in xyna_strli. Robust residue interactions within these secondary structures are key factors influencing xyna_strli and xyna_theau thermostability. Analyzing the rigid-community can elucidate the cooperation of secondary structures, which cannot be discovered from sequence and 3D structure alone.
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Tu T, Wang Z, Luo Y, Li Y, Su X, Wang Y, Zhang J, Rouvinen J, Yao B, Hakulinen N, Luo H. Structural Insights into the Mechanisms Underlying the Kinetic Stability of GH28 Endo-Polygalacturonase. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2021; 69:815-823. [PMID: 33404235 DOI: 10.1021/acs.jafc.0c06941] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Thermostability is a key property of industrial enzymes. Endo-polygalacturonases of the glycoside hydrolase family 28 have many practical applications, but only few of their structures have been determined, and the reasons for their stability remain unclear. We identified and characterized the Talaromyces leycettanus JCM12802 endo-polygalacturonase TlPGA, which differs from other GH28 family members because of its high catalytic activity, with an optimum temperature of 70 °C. Distinctive features were revealed by comparison of thermophilic TlPGA and all known structures of fungal endo-polygalacturonases, including a relatively large exposed polar accessible surface area in thermophilic TlPGA. By mutating potentially important residues in thermophilic TlPGA, we identified Thr284 as a critical residue. Mutant T284A was comparable to thermophilic TlPGA in melting temperature but exhibited a significantly lower half-life and half-inactivation temperature, implicating residue Thr284 in the kinetic stability of thermophilic TlPGA. Structure analysis of thermophilic TlPGA and mutant T284A revealed that a carbon-oxygen hydrogen bond between the hydroxyl group of Thr284 and the Cα atom of Gln255, and the stable conformation adopted by Gln255, contribute to its kinetic stability. Our results clarify the mechanism underlying the kinetic stability of GH28 endo-polygalacturonases and may guide the engineering of thermostable enzymes for industrial applications.
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Affiliation(s)
- Tao Tu
- Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing 100193, PR China
| | - Zhiyun Wang
- Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing 100193, PR China
| | - Yan Luo
- Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing 100193, PR China
| | - Yeqing Li
- Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing 100193, PR China
| | - Xiaoyun Su
- Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing 100193, PR China
| | - Yuan Wang
- Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing 100193, PR China
| | - Jie Zhang
- Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing 100193, PR China
| | - Juha Rouvinen
- Department of Chemistry, University of Eastern Finland, Joensuu 80130, Finland
| | - Bin Yao
- Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing 100193, PR China
| | - Nina Hakulinen
- Department of Chemistry, University of Eastern Finland, Joensuu 80130, Finland
| | - Huiying Luo
- Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing 100193, PR China
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Wang J, Liang J, Li Y, Tian L, Wei Y. Characterization of efficient xylanases from industrial-scale pulp and paper wastewater treatment microbiota. AMB Express 2021; 11:19. [PMID: 33464408 PMCID: PMC7815853 DOI: 10.1186/s13568-020-01178-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Accepted: 12/31/2020] [Indexed: 02/08/2023] Open
Abstract
Xylanases are widely used enzymes in the food, textile, and paper industries. Most efficient xylanases have been identified from lignocellulose-degrading microbiota, such as the microbiota of the cow rumen and the termite hindgut. Xylanase genes from efficient pulp and paper wastewater treatment (PPWT) microbiota have been previously recovered by metagenomics, assigning most of the xylanase genes to the GH10 family. In this study, a total of 40 GH10 family xylanase genes derived from a certain PPWT microbiota were cloned and expressed in Escherichia coli BL21 (DE3). Among these xylanase genes, 14 showed xylanase activity on beechwood substrate. Two of these, PW-xyl9 and PW-xyl37, showed high activities, and were purified to evaluate their xylanase properties. Values of optimal pH and temperature for PW-xyl9 were pH 7 and 60 ℃, respectively, while those for PW-xyl37 were pH 7 and 55 ℃, respectively; their specific xylanase activities under optimal conditions were 470.1 U/mg protein and 113.7 U/mg protein, respectively. Furthermore, the Km values of PW-xyl9 and PW-xyl37 were determined as 8.02 and 18.8 g/L, respectively. The characterization of these two xylanases paves the way for potential application in future pulp and paper production and other industries, indicating that PPWT microbiota has been an undiscovered reservoir of efficient lignocellulase genes. This study demonstrates that a metagenomic approach has the potential to screen efficient xylanases of uncultured microorganisms from lignocellulose-degrading microbiota. In a similar way, other efficient lignocellulase genes might be identified from PPWT treatment microbiota in the future.
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Bhardwaj N, Kumar B, Verma P. A detailed overview of xylanases: an emerging biomolecule for current and future prospective. BIORESOUR BIOPROCESS 2019. [DOI: 10.1186/s40643-019-0276-2] [Citation(s) in RCA: 144] [Impact Index Per Article: 28.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Abstract
Xylan is the second most abundant naturally occurring renewable polysaccharide available on earth. It is a complex heteropolysaccharide consisting of different monosaccharides such as l-arabinose, d-galactose, d-mannoses and organic acids such as acetic acid, ferulic acid, glucuronic acid interwoven together with help of glycosidic and ester bonds. The breakdown of xylan is restricted due to its heterogeneous nature and it can be overcome by xylanases which are capable of cleaving the heterogeneous β-1,4-glycoside linkage. Xylanases are abundantly present in nature (e.g., molluscs, insects and microorganisms) and several microorganisms such as bacteria, fungi, yeast, and algae are used extensively for its production. Microbial xylanases show varying substrate specificities and biochemical properties which makes it suitable for various applications in industrial and biotechnological sectors. The suitability of xylanases for its application in food and feed, paper and pulp, textile, pharmaceuticals, and lignocellulosic biorefinery has led to an increase in demand of xylanases globally. The present review gives an insight of using microbial xylanases as an “Emerging Green Tool” along with its current status and future prospective.
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Atalah J, Cáceres-Moreno P, Espina G, Blamey JM. Thermophiles and the applications of their enzymes as new biocatalysts. BIORESOURCE TECHNOLOGY 2019; 280:478-488. [PMID: 30826176 DOI: 10.1016/j.biortech.2019.02.008] [Citation(s) in RCA: 121] [Impact Index Per Article: 24.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Revised: 01/31/2019] [Accepted: 02/01/2019] [Indexed: 05/20/2023]
Abstract
Ecological and efficient alternatives to industrial processes have sparked interest for using microorganisms and enzymes as biocatalysts. One of the difficulties is finding candidates capable of resisting the harsh conditions in which industrial processes usually take place. Extremophiles, microorganisms naturally found in "extreme" ecological niches, produce robust enzymes for bioprocesses and product development. Thermophiles like Geobacillus, Alyciclobacillus, Anoxybacillus, Pyrococcus and Thermoccocus are some of the extremophiles containing enzymes showing special promise for biocatalysis. Glutamate dehydrogenase used in food processes, laccases and xylanases in pulp and paper processes, nitrilases and transaminases for pharmaceutical drug synthesis and lipases present in detergents, are examples of the increasing use of enzymes for biocatalytic synthesis from thermophilic microorganisms. Some of these enzymes from thermophiles have been expressed as recombinant enzymes and are already in the market. Here we will review recent discoveries of thermophilic enzymes and their current and potential applications in industry.
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Affiliation(s)
- Joaquín Atalah
- Fundación Biociencia, José Domingo Cañas 2280, Ñuñoa, Santiago, Chile
| | | | - Giannina Espina
- Fundación Biociencia, José Domingo Cañas 2280, Ñuñoa, Santiago, Chile
| | - Jenny M Blamey
- Fundación Biociencia, José Domingo Cañas 2280, Ñuñoa, Santiago, Chile; Facultad de Química y Biología, Universidad de Santiago de Chile, Alameda 3363, Estación Central, Santiago, Chile.
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Kim HB, Lee KT, Kim MJ, Lee JS, Kim KS. Identification and characterization of a novel KG42 xylanase (GH10 family) isolated from the black goat rumen-derived metagenomic library. Carbohydr Res 2018; 469:1-9. [PMID: 30170217 DOI: 10.1016/j.carres.2018.08.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Revised: 08/14/2018] [Accepted: 08/17/2018] [Indexed: 11/18/2022]
Abstract
This study was conducted to isolate and functionally characterize a novel xylan-degrading enzyme from the microbial metagenomes of black goat rumens. A novel gene, KG42, was isolated from one of the 17 xylan-degrading metagenomic fosmid clones obtained from black goat rumens. The KG42 gene, comprising a 1107 bp open reading frame, encodes a protein composed of 368 amino acids (41 kDa) with a glycosyl hydrolase family 10 (GH10) domain, consisting of a "salad-bowl" shaped tertiary structure (a typical 8-fold α/β barrel (α/β)8) and two catalytic residues. KG42 xylanase protein has at best 40% sequence identity with other homologous GH10 xylanase proteins. The enzyme displayed its optimum activity at pH 5.0 and 50 °C. The enzyme was thermally stable at pH and temperature ranges of 5.0-10.0 and 20-60 °C, respectively. Substrate specificity and hydrolytic patterns implied that the KG42 xylanase functions as an endo-β-1,4-xylanase (EC 3.2.1.8). The KG42 xylanase was also used for the preparation of bifidogenic xylan hydrolysates, demonstrating its potential applications toward preparing prebiotic xylooligosaccharides.
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Affiliation(s)
- Hye-Bin Kim
- Department of Food Science and Technology, Chung-Ang University, Ansung, 456-756, South Korea
| | - Kyung-Tai Lee
- Animal Genomics and Bioinformatics Division, National Institute of Animal Science, Rural Development Administration, Wanju, 565-851, South Korea
| | - Min-Ju Kim
- Department of Food Science and Technology, Chung-Ang University, Ansung, 456-756, South Korea
| | - Jin-Sung Lee
- Department of Biological Sciences, Kyonggi University, Suwon, 442-760, South Korea
| | - Keun-Sung Kim
- Department of Food Science and Technology, Chung-Ang University, Ansung, 456-756, South Korea.
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17
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Low-resolution SAXS and comparative modeling based structure analysis of endo-β-1,4-xylanase a family 10 glycoside hydrolase from Pseudopedobacter saltans comb. nov. Int J Biol Macromol 2018; 112:1104-1114. [DOI: 10.1016/j.ijbiomac.2018.02.037] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2017] [Revised: 02/05/2018] [Accepted: 02/07/2018] [Indexed: 11/20/2022]
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Basit A, Liu J, Rahim K, Jiang W, Lou H. Thermophilic xylanases: from bench to bottle. Crit Rev Biotechnol 2018; 38:989-1002. [DOI: 10.1080/07388551.2018.1425662] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Abdul Basit
- Beijing Advanced Innovation Center for Food Nutrition and Human Health and State Key Laboratory of Agro-Biotechnology, College of Biological Sciences, China Agricultural University, Beijing, China
| | - Junquan Liu
- Beijing Advanced Innovation Center for Food Nutrition and Human Health and State Key Laboratory of Agro-Biotechnology, College of Biological Sciences, China Agricultural University, Beijing, China
| | - Kashif Rahim
- Beijing Key Laboratory of Genetic Engineering Drug and Biotechnology, Institute of Biochemistry and Biotechnology, College of Life Sciences, Beijing Normal University, Beijing, China
| | - Wei Jiang
- Beijing Advanced Innovation Center for Food Nutrition and Human Health and State Key Laboratory of Agro-Biotechnology, College of Biological Sciences, China Agricultural University, Beijing, China
| | - Huiqiang Lou
- Beijing Advanced Innovation Center for Food Nutrition and Human Health and State Key Laboratory of Agro-Biotechnology, College of Biological Sciences, China Agricultural University, Beijing, China
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Liu X, Liu T, Zhang Y, Xin F, Mi S, Wen B, Gu T, Shi X, Wang F, Sun L. Structural Insights into the Thermophilic Adaption Mechanism of Endo-1,4-β-Xylanase from Caldicellulosiruptor owensensis. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2018; 66:187-193. [PMID: 29236500 DOI: 10.1021/acs.jafc.7b03607] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Xylanases (EC 3.2.1.8) are a kind of enzymes degrading xylan to xylooligosaccharides (XOS) and have been widely used in a variety of industrial applications. Among them, xylanases from thermophilic microorganisms have distinct advantages in industries that require high temperature conditions. The CoXynA gene, encoding a glycoside hydrolase (GH) family 10 xylanase, was identified from thermophilic Caldicellulosiruptor owensensis and was overexpressed in Escherichia coli. Recombinant CoXynA showed optimal activity at 90 °C with a half-life of about 1 h at 80 °C and exhibited highest activity at pH 7.0. The activity of CoXynA activity was affected by a variety of cations. CoXynA showed distinct substrate specificities for beechwood xylan and birchwood xylan. The crystal structure of CoXynA was solved and a molecular dynamics simulation of CoXynA was performed. The relatively high thermostability of CoXynA was proposed to be due to the increased overall protein rigidity resulting from the reduced length and fluctuation of Loop 7.
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Affiliation(s)
- Xin Liu
- Laboratory of Biomanufacturing and Food Engineering, Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences , Beijing 100193, P.R. China
| | - Tengfei Liu
- School of Chinese Materia Medica, Beijing University of Chinese Medicine , Beijing 100102, P.R. China
| | - Yuebin Zhang
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences , 457 Zhongshan Rd, Dalian 116023, P.R. China
| | - Fengjiao Xin
- Laboratory of Biomanufacturing and Food Engineering, Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences , Beijing 100193, P.R. China
| | - Shuofu Mi
- National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences , Beijing 100190, P.R. China
| | - Boting Wen
- Laboratory of Biomanufacturing and Food Engineering, Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences , Beijing 100193, P.R. China
| | - Tianyi Gu
- Laboratory of Biomanufacturing and Food Engineering, Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences , Beijing 100193, P.R. China
| | - Xinyuan Shi
- School of Chinese Materia Medica, Beijing University of Chinese Medicine , Beijing 100102, P.R. China
| | - Fengzhong Wang
- Laboratory of Biomanufacturing and Food Engineering, Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences , Beijing 100193, P.R. China
| | - Lichao Sun
- Laboratory of Biomanufacturing and Food Engineering, Institute of Food Science and Technology, Chinese Academy of Agricultural Sciences , Beijing 100193, P.R. China
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