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Hamre AG, Al-Sadawi R, Johannesen KM, Bisarro B, Kjendseth ÅR, Leiros HKS, Sørlie M. Initial characterization of an iron superoxide dismutase from Thermobifida fusca. J Biol Inorg Chem 2023; 28:689-698. [PMID: 37725277 PMCID: PMC10520107 DOI: 10.1007/s00775-023-02019-9] [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: 11/16/2022] [Accepted: 08/24/2023] [Indexed: 09/21/2023]
Abstract
Superoxide dismutases (SODs) are enzymes that catalyze the dismutation of the superoxide radical anion into O2 and H2O2 in a two-step reaction. They are ubiquitous to all forms of life and four different types of metal centers are detected, dividing this class of enzymes into Cu-/Zn-, Ni-, Mn-, and Fe-SODs. In this study, a superoxide dismutase from the thermophilic bacteria Thermobifida fusca (TfSOD) was cloned and expressed before the recombinant enzyme was characterized. The enzyme was found to be active for superoxide dismutation measured by inhibition of cytochrome c oxidation and the inhibition of the autoxidation of pyrogallol. Its pH-optimum was determined to be 7.5, while it has a broad temperature optimum ranging from 20 to 90 °C. Combined with the Tm that was found to be 78.5 ± 0.5 °C at pH 8.0, TfSOD can be defined as a thermostable enzyme. Moreover, the crystal structure of TfSOD was determined and refined to 1.25 Å resolution. With electron paramagnetic resonance spectroscopy, it was confirmed that iron is the metal co-factor of TfSOD. The cell potential (Em) for the TfSOD-Fe3+/TfSOD-Fe2+ redox couple was determined to be 287 mV.
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Affiliation(s)
- Anne Grethe Hamre
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, PO 5003, 1432, Ås, Norway
| | - Rim Al-Sadawi
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, PO 5003, 1432, Ås, Norway
| | - Kirsti Merete Johannesen
- Department of Chemistry, Faculty of Science and Technology, UiT The Arctic University of Norway, 9037, Tromsö, Norway
| | - Bastien Bisarro
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, PO 5003, 1432, Ås, Norway
| | - Åsmund Røhr Kjendseth
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, PO 5003, 1432, Ås, Norway
| | - Hanna-Kirsti S Leiros
- Department of Chemistry, Faculty of Science and Technology, UiT The Arctic University of Norway, 9037, Tromsö, Norway
| | - Morten Sørlie
- Department of Chemistry, Biotechnology and Food Science, Norwegian University of Life Sciences, PO 5003, 1432, Ås, Norway.
- Department for Physics and Technology, Faculty of Science and Technology, UiT The Arctic University of Norway, 9037, Tromsö, Norway.
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2
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Qiao J, Sheng Y, Wang M, Li A, Li X, Huang H. Evolving Robust and Interpretable Enzymes for the Bioethanol Industry. Angew Chem Int Ed Engl 2023; 62:e202300320. [PMID: 36701239 DOI: 10.1002/anie.202300320] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2023] [Revised: 01/19/2023] [Accepted: 01/26/2023] [Indexed: 01/27/2023]
Abstract
Obtaining a robust and applicable enzyme for bioethanol production is a dream for biorefinery engineers. Herein, we describe a general method to evolve an all-round and interpretable enzyme that can be directly employed in the bioethanol industry. By integrating the transferable protein evolution strategy InSiReP 2.0 (In Silico guided Recombination Process), enzymatic characterization for actual production, and computational molecular understanding, the model cellulase PvCel5A (endoglucanase II Cel5A from Penicillium verruculosum) was successfully evolved to overcome the remaining challenges of low ethanol and temperature tolerance, which primarily limited biomass transformation and bioethanol yield. Remarkably, application of the PvCel5A variants in both first- and second-generation bioethanol production processes (i. Conventional corn ethanol fermentation combined with the in situ pretreatment process; ii. cellulosic ethanol fermentation process) resulted in a 5.7-10.1 % increase in the ethanol yield, which was unlikely to be achieved by other optimization techniques.
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Affiliation(s)
- Jie Qiao
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, No. 2 Xuelin Road, Nanjing, 210097, China
| | - Yijie Sheng
- 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
| | - Anni Li
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, No. 2 Xuelin Road, Nanjing, 210097, China
| | - Xiujuan Li
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, No. 2 Xuelin Road, Nanjing, 210097, China
| | - He Huang
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, No. 2 Xuelin Road, Nanjing, 210097, China.,School of Pharmaceutical Science, Nanjing Tech University, Nanjing, 211816, China
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3
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Sakarika M, Regueira A, Rabaey K, Ganigué R. Thermophilic caproic acid production from grass juice by sugar-based chain elongation. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 860:160501. [PMID: 36436634 DOI: 10.1016/j.scitotenv.2022.160501] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Revised: 11/04/2022] [Accepted: 11/21/2022] [Indexed: 06/16/2023]
Abstract
Medium chain carboxylic acids (MCCA) such as caproic acid have a plethora of applications, ranging from food additives to bioplastics. MCCA can be produced via microbial chain elongation using waste and side-streams as substrates, a process that can be more sustainable than conventional production routes. Most chain elongation studies have focused on mesophilic conditions, with only two recent studies hinting at the possibility of thermophilic chain elongation, but a systematic study of its mechanisms is lacking. Here, we investigated thermophilic chain elongation from grass juice, to understand the effect of key operational parameters (pH, temperature, substrate) on the process performance and to establish the key microbial genera and their role in the system. The genus Caproiciproducens was identified as responsible for thermophilic chain elongation, and caproic acid production was most favorable at pH 6.0 and 50 °C among the conditions tested, reaching an average concentration of 3.4 g/L. Batch experiments showed that the substrate for caproic acid production were glucose and xylose, while lactic acid led to the production of only butyric acid. Fed-batch experiments showed that substrate availability and the presence of caproic acid in the system play a major role in shaping the profile of thermophilic chain elongation. The increase of the total sugar concentration by glucose addition (without changing the organic load) during continuous operation led to a microbial community dominated (75 %) by Caproiciproducens and increased by 76 % the final average caproic acid concentration to 6.0 g/L (13 gCOD/L) which represented 32 % (g/g) of the total carboxylic acids. The highest concentration achieved was 7.2 g/L (day 197) which is the highest concentration reported under thermophilic conditions thus far. The results of this work pave the way to the potential development of thermophilic systems for upgrading various underexplored abundant and cheap sugar-rich side-streams to caproic acid.
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Affiliation(s)
- Myrsini Sakarika
- Center for Microbial Ecology and Technology (CMET), Faculty of Bioscience Engineering Ghent University, Coupure Links 653, 9000 Ghent, Belgium; Center for Advanced Process Technology for Urban Resource recovery (CAPTURE), Frieda Saeysstraat, 9052 Ghent, Belgium
| | - Alberte Regueira
- Center for Microbial Ecology and Technology (CMET), Faculty of Bioscience Engineering Ghent University, Coupure Links 653, 9000 Ghent, Belgium; Center for Advanced Process Technology for Urban Resource recovery (CAPTURE), Frieda Saeysstraat, 9052 Ghent, Belgium; Cross-disciplinary Research in Environmental Technologies (CRETUS), Department of Chemical Engineering, Universidade de Santiago de Compostela, Spain
| | - Korneel Rabaey
- Center for Microbial Ecology and Technology (CMET), Faculty of Bioscience Engineering Ghent University, Coupure Links 653, 9000 Ghent, Belgium; Center for Advanced Process Technology for Urban Resource recovery (CAPTURE), Frieda Saeysstraat, 9052 Ghent, Belgium
| | - Ramon Ganigué
- Center for Microbial Ecology and Technology (CMET), Faculty of Bioscience Engineering Ghent University, Coupure Links 653, 9000 Ghent, Belgium; Center for Advanced Process Technology for Urban Resource recovery (CAPTURE), Frieda Saeysstraat, 9052 Ghent, Belgium.
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4
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Zhu W, Qin L, Xu Y, Lu H, Wu Q, Li W, Zhang C, Li X. Three Molecular Modification Strategies to Improve the Thermostability of Xylanase XynA from Streptomyces rameus L2001. Foods 2023; 12:foods12040879. [PMID: 36832954 PMCID: PMC9957083 DOI: 10.3390/foods12040879] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Revised: 02/07/2023] [Accepted: 02/13/2023] [Indexed: 02/22/2023] Open
Abstract
Glycoside hydrolase family 11 (GH11) xylanases are the preferred candidates for the production of functional oligosaccharides. However, the low thermostability of natural GH11 xylanases limits their industrial applications. In this study, we investigated the following three strategies to modify the thermostability of xylanase XynA from Streptomyces rameus L2001 mutation to reduce surface entropy, intramolecular disulfide bond construction, and molecular cyclization. Changes in the thermostability of XynA mutants were analyzed using molecular simulations. All mutants showed improved thermostability and catalytic efficiency compared with XynA, except for molecular cyclization. The residual activities of high-entropy amino acid-replacement mutants Q24A and K104A increased from 18.70% to more than 41.23% when kept at 65 °C for 30 min. The catalytic efficiencies of Q24A and K143A increased to 129.99 and 92.26 mL/s/mg, respectively, compared with XynA (62.97 mL/s/mg) when using beechwood xylan as the substrate. The mutant enzyme with disulfide bonds formed between Val3 and Thr30 increased the t1/260 °C by 13.33-fold and the catalytic efficiency by 1.80-fold compared with the wild-type XynA. The high thermostabilities and hydrolytic activities of XynA mutants will be useful for enzymatic production of functional xylo-oligosaccharides.
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Affiliation(s)
- Weijia Zhu
- School of Food and Health, Beijing Technology and Business University (BTBU), Beijing 100048, China
| | - Liqin Qin
- School of Food and Health, Beijing Technology and Business University (BTBU), Beijing 100048, China
| | - Youqiang Xu
- School of Food and Health, Beijing Technology and Business University (BTBU), Beijing 100048, China
| | - Hongyun Lu
- School of Food and Health, Beijing Technology and Business University (BTBU), Beijing 100048, China
| | - Qiuhua Wu
- School of Food and Health, Beijing Technology and Business University (BTBU), Beijing 100048, China
| | - Weiwei Li
- Key Laboratory of Brewing Microbiome and Enzymatic Molecular Engineering, China General Chamber of Commerce, Beijing 100048, China
- Key Laboratory of Brewing Molecular Engineering of China Light Industry, Beijing Technology and Business University, Beijing 100048, China
| | - Chengnan Zhang
- Key Laboratory of Brewing Microbiome and Enzymatic Molecular Engineering, China General Chamber of Commerce, Beijing 100048, China
- Key Laboratory of Brewing Molecular Engineering of China Light Industry, Beijing Technology and Business University, Beijing 100048, China
| | - Xiuting Li
- School of Food and Health, Beijing Technology and Business University (BTBU), Beijing 100048, China
- Key Laboratory of Brewing Microbiome and Enzymatic Molecular Engineering, China General Chamber of Commerce, Beijing 100048, China
- Key Laboratory of Brewing Molecular Engineering of China Light Industry, Beijing Technology and Business University, Beijing 100048, China
- Correspondence:
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Sürmeli Y, Şanlı-Mohamed G. Engineering of xylanases for the development of biotechnologically important characteristics. Biotechnol Bioeng 2023; 120:1171-1188. [PMID: 36715367 DOI: 10.1002/bit.28339] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2022] [Revised: 12/19/2022] [Accepted: 01/26/2023] [Indexed: 01/31/2023]
Abstract
Xylanases are the main biocatalysts used for the reduction of the xylan backbone from hemicellulose, randomly splitting off β-1,4-glycosidic linkages between xylopyranosyl residues. Xylanase market has been annually estimated at 500 million US Dollars and they are potentially used in broad industrial process ranges such as paper pulp biobleaching, xylo-oligosaccharide production, and biofuel manufacture from lignocellulose. The highly stable xylanases are preferred in the downstream procedure of industrial processes because they can tolerate severe conditions. Almost all native xylanases can not endure adverse conditions thus they are industrially not proper to be utilized. Protein engineering is a powerful technology for developing xylanases, which can effectively work in adverse conditions and can meet requirements for industrial processes. This study considered state-of-the-art strategies of protein engineering for creating the xylanase gene diversity, high-throughput screening systems toward upgraded traits of the xylanases, and the prediction and comprehensive analysis of the target mutations in xylanases by in silico methods. Also, key molecular factors have been elucidated for industrial characteristics (alkaliphilic enhancement, thermal stability, and catalytic performance) of GH11 family xylanases. The present review explores industrial characteristics improved by directed evolution, rational design, and semi-rational design as protein engineering approaches for pulp bleaching process, xylooligosaccharides production, and biorefinery & bioenergy production.
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Affiliation(s)
- Yusuf Sürmeli
- Department of Agricultural Biotechnology, Tekirdağ Namık Kemal University, Tekirdağ, Turkey
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6
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Abedi E, Fatemi F, Sefidbakht Y, Siadat SER. Development and characterization of a thermostable GH11/GH10 xylan degrading chimeric enzyme. Enzyme Microb Technol 2021; 149:109854. [PMID: 34311891 DOI: 10.1016/j.enzmictec.2021.109854] [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: 06/23/2020] [Revised: 05/24/2021] [Accepted: 06/11/2021] [Indexed: 11/26/2022]
Abstract
Xylanases are categorized into different family groups, two of which are glycoside hydrolases 10 (GH10) and 11 (GH11) families. These well-characterized xylanases demonstrate different modes of action in hydrolysis of xylans. Imitating certain types of microorganisms to produce bifunctional enzymes such as engineered xylanases has gained considerable attention among researchers. In this study, a recombinant chimeric enzyme (X11-10) was designed by fusing two thermostable xylanases through a peptide linker. The recombinant parental enzymes, xylanase 10 from fungus Bispora sp. MEY-1 (X10) and xylanase 11 from bacterium Thermobacillus xylanilyticus (X11), and their chimera were successfully expressed in Pichia pastoris (P. pastoris), purified, and characterized. Being active over a wide pH range, X11-10 chimera showed higher thermal stability, possessed a lower Km, and a higher catalytic efficiency (kcat/Km) in comparison to the parental enzymes. Also, molecular dynamics simulation (MDS) of X11-10 revealed that its active site residues were free to interact with substrate. This novel chimeric xylanase may have potential applications in different industrial processes since it can substitute two separate enzymes and therefore minimize the production costs.
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Affiliation(s)
- Ehsan Abedi
- Protein Research Center, Shahid Beheshti University G.C., Tehran, Iran
| | - Fataneh Fatemi
- Protein Research Center, Shahid Beheshti University G.C., Tehran, Iran.
| | - Yahya Sefidbakht
- Protein Research Center, Shahid Beheshti University G.C., Tehran, Iran
| | - Seyed Ehsan Ranaei Siadat
- Sobhan Recombinant Protein, No. 22, 2nd Noavari St, Pardis Technology Park, 20th Km of Damavand Road, Tehran, Iran.
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7
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Talens-Perales D, Jiménez-Ortega E, Sánchez-Torres P, Sanz-Aparicio J, Polaina J. Phylogenetic, functional and structural characterization of a GH10 xylanase active at extreme conditions of temperature and alkalinity. Comput Struct Biotechnol J 2021; 19:2676-2686. [PMID: 34093984 PMCID: PMC8148631 DOI: 10.1016/j.csbj.2021.05.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Revised: 04/29/2021] [Accepted: 05/01/2021] [Indexed: 01/31/2023] Open
Abstract
Endoxylanases active under extreme conditions of
temperature and alkalinity can replace the use of highly pollutant chemicals in
the pulp and paper industry. Searching for enzymes with these properties, we
carried out a comprehensive bioinformatics study of the GH10 family. The
phylogenetic analysis allowed the construction of a radial cladogram in which
protein sequences putatively ascribed as thermophilic and alkaliphilic appeared
grouped in a well-defined region of the cladogram, designated TAK Cluster. One
among five TAK sequences selected for experimental analysis (Xyn11) showed
extraordinary xylanolytic activity under simultaneous conditions of high
temperature (90 °C) and alkalinity (pH 10.5). Addition of a carbohydrate binding
domain (CBM2) at the C-terminus of the protein sequence further improved the
activity of the enzyme at high pH. Xyn11 structure, which has been solved at
1.8 Å resolution by X-ray crystallography, reveals an unusually high number of
hydrophobic, ionic and hydrogen bond atomic interactions that could account for
the enzyme’s extremophilic nature.
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Affiliation(s)
- David Talens-Perales
- Institute of Agrochemistry and Food Technology, Spanish National Research Council (CSIC), Paterna, Valencia, Spain
| | - Elena Jiménez-Ortega
- Institute of Physical-Chemistry Rocasolano, Spanish National Research Council (CSIC), Madrid, Spain
| | - Paloma Sánchez-Torres
- Institute of Agrochemistry and Food Technology, Spanish National Research Council (CSIC), Paterna, Valencia, Spain
| | - Julia Sanz-Aparicio
- Institute of Physical-Chemistry Rocasolano, Spanish National Research Council (CSIC), Madrid, Spain
| | - Julio Polaina
- Institute of Agrochemistry and Food Technology, Spanish National Research Council (CSIC), Paterna, Valencia, Spain
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Complete Genome Sequence of Pedobacter sp. PAMC26386 and Their Low Temperature Application in Arabinose-containing Polysaccharides Degradation. Curr Microbiol 2021; 78:944-953. [PMID: 33638002 DOI: 10.1007/s00284-021-02364-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Accepted: 01/29/2021] [Indexed: 10/22/2022]
Abstract
Pedobacter are a representative genus of soil-associated bacteria. Here we have provided the complete genome sequence of Pedobacter sp. PAMC26386 isolated from Antarctic soil, and functionally annotated the genome, describing the unique features of carbohydrate active enzymes (CAZymes) and α-L-arabinofuranosidase (α-L-ABF). The genome of Pedobacter sp. PAMC26386 is circular and comprises 4,796,773 bp, with a 38.2% GC content. The genome encodes 4,175 genes, including 7 rRNA and 44 tRNA genes. We identified 172 genes (8 auxiliary activities, 8 carbohydrate binding modules, 23 carbohydrate esterases, 86 glycoside hydrolases, 42 glycosyl transferases, and 5 polysaccharide lyases) related to CAZymes using the dbCAN2 tool. We checked enzyme activity on 11 substrates using the AZCL assay and obtained strong activity for arabinooligosaccharide and hemicellulose. This includes information regarding α-L-ABF, which is active at low temperatures, based on the annotation results. Our findings on Pedobacter sp. PAMC26386 provide the basis for research in the future. The favorable properties of Pedobacter sp. PAMC26386 make it a good candidate for industrial applications involving low temperatures.
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Hebal H, Boucherba N, Binay B, Turunen O. Activity and stability of hyperthermostable cellulases and xylanases in ionic liquids. BIOCATAL BIOTRANSFOR 2021. [DOI: 10.1080/10242422.2021.1882430] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- Hakim Hebal
- Laboratoire de Microbiologie Appliquée (LMA), Faculté des Sciences de La Nature et de La Vie (FSNV), Université de Bejaia, Bejaia, Algeria
- Faculty of Exact Sciences and Sciences of Nature and Life, Department of Biology, Mohamed Khider University of Biskra, Biskra, Algeria
| | - Nawel Boucherba
- Laboratoire de Microbiologie Appliquée (LMA), Faculté des Sciences de La Nature et de La Vie (FSNV), Université de Bejaia, Bejaia, Algeria
| | - Baris Binay
- Department of Bioengineering, Gebze Technical University, Kocaeli, Turkey
| | - Ossi Turunen
- School of Forest Sciences, University of Eastern Finland, Joensuu, Finland
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Effects of the outer-cleft aromatic ring deletion on the resistivity of a GH11 xylanase to the lignin-like monolignol aggregates. Chem Phys Lett 2021. [DOI: 10.1016/j.cplett.2020.138141] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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Talens-Perales D, Sánchez-Torres P, Marín-Navarro J, Polaina J. In silico screening and experimental analysis of family GH11 xylanases for applications under conditions of alkaline pH and high temperature. BIOTECHNOLOGY FOR BIOFUELS 2020; 13:198. [PMID: 33372612 PMCID: PMC7720462 DOI: 10.1186/s13068-020-01842-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Accepted: 11/24/2020] [Indexed: 06/12/2023]
Abstract
BACKGROUND Xylanases are one of the most extensively used enzymes for biomass digestion. However, in many instances, their use is limited by poor performance under the conditions of pH and temperature required by the industry. Therefore, the search for xylanases able to function efficiently at alkaline pH and high temperature is an important objective for different processes that use lignocellulosic substrates, such as the production of paper pulp and biofuels. RESULTS A comprehensive in silico analysis of family GH11 sequences from the CAZY database allowed their phylogenetic classification in a radial cladogram in which sequences of known or presumptive thermophilic and alkalophilic xylanases appeared in three clusters. Eight sequences from these clusters were selected for experimental analysis. The coding DNA was synthesized, cloned and the enzymes were produced in E. coli. Some of these showed high xylanolytic activity at pH values > 8.0 and temperature > 80 °C. The best enzymes corresponding to sequences from Dictyoglomus thermophilum (Xyn5) and Thermobifida fusca (Xyn8). The addition of a carbohydrate-binding module (CBM9) to Xyn5 increased 4 times its activity at 90 °C and pH > 9.0. The combination of Xyn5 and Xyn8 was proved to be efficient for the saccharification of alkali pretreated rice straw, yielding xylose and xylooligosaccharides. CONCLUSIONS This study provides a fruitful approach for the selection of enzymes with suitable properties from the information contained in extensive databases. We have characterized two xylanases able to hydrolyze xylan with high efficiency at pH > 8.0 and temperature > 80 °C.
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Affiliation(s)
- David Talens-Perales
- Department of Food Biotechnology. Institute of Agrochemistry and Food Technology, Spanish National Research Council (IATA-CSIC), Paterna, Valencia, Spain
| | - Paloma Sánchez-Torres
- Department of Food Biotechnology. Institute of Agrochemistry and Food Technology, Spanish National Research Council (IATA-CSIC), Paterna, Valencia, Spain
| | - Julia Marín-Navarro
- Department of Food Biotechnology. Institute of Agrochemistry and Food Technology, Spanish National Research Council (IATA-CSIC), Paterna, Valencia, Spain
- Department of Biochemistry and Molecular Biology, University of Valencia, Valencia, Spain
| | - Julio Polaina
- Department of Food Biotechnology. Institute of Agrochemistry and Food Technology, Spanish National Research Council (IATA-CSIC), Paterna, Valencia, Spain.
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High-resolution crystal structure and biochemical characterization of a GH11 endoxylanase from Nectria haematococca. Sci Rep 2020; 10:15658. [PMID: 32973265 PMCID: PMC7519127 DOI: 10.1038/s41598-020-72644-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Accepted: 08/28/2020] [Indexed: 11/08/2022] Open
Abstract
Enzymatic degradation of vegetal biomass offers versatile procedures to improve the production of alternative fuels and other biomass-based products. Here we present the three-dimensional structure of a xylanase from Nectria haematococca (NhGH11) at 1.0 Å resolution and its functional properties. The atomic resolution structure provides details and insights about the complex hydrogen bonding network of the active site region and allowed a detailed comparison with homologous structures. Complementary biochemical studies showed that the xylanase can catalyze the hydrolysis of complex xylan into simple xylose aldopentose subunits of different lengths. NhGH11 can catalyze the efficient breakdown of beechwood xylan, xylan polysaccharide, and wheat arabinoxylan with turnover numbers of 1730.6 ± 318.1 min-1, 1648.2 ± 249.3 min-1 and 2410.8 ± 517.5 min-1 respectively. NhGH11 showed maximum catalytic activity at pH 6.0 and 45 °C. The mesophilic character of NhGH11 can be explained by distinct structural features in comparison to thermophilic GH11 enzymes, including the number of hydrogen bonds, side chain interactions and number of buried water molecules. The enzymatic activity of NhGH11 is not very sensitive to metal ions and chemical reagents that are typically present in associated industrial production processes. The data we present highlights the potential of NhGH11 to be applied in industrial biomass degradation processes.
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13
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Enhanced Thermostability and Enzymatic Activity of Cel6A Variants from Thermobifida fusca by Empirical Domain Engineering (Short Title: Domain Engineering of Cel6A). BIOLOGY 2020; 9:biology9080214. [PMID: 32784797 PMCID: PMC7464639 DOI: 10.3390/biology9080214] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 07/29/2020] [Accepted: 08/02/2020] [Indexed: 02/07/2023]
Abstract
Cellulases are a set of lignocellulolytic enzymes, capable of producing eco-friendly low-cost renewable bioethanol. However, low stability and hydrolytic activity limit their wide-scale applicability at the industrial scale. In this work, we report the domain engineering of endoglucanase (Cel6A) of Thermobifida fusca to improve their catalytic activity and thermal stability. Later, enzymatic activity and thermostability of the most efficient variant named as Cel6A.CBC was analyzed by molecular dynamics simulations. This variant demonstrated profound activity against soluble and insoluble cellulosic substrates like filter paper, alkali-treated bagasse, regenerated amorphous cellulose (RAC), and bacterial microcrystalline cellulose. The variant Cel6A.CBC showed the highest catalysis of carboxymethyl cellulose (CMC) and other related insoluble substrates at a pH of 6.0 and a temperature of 60 °C. Furthermore, a sound rationale was observed between experimental findings and molecular modeling of Cel6A.CBC which revealed thermostability of Cel6A.CBC at 26.85, 60.85, and 74.85 °C as well as structural flexibility at 126.85 °C. Therefore, a thermostable derivative of Cel6A engineered in the present work has enhanced biological performance and can be a useful construct for the mass production of bioethanol from plant biomass.
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14
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Alokika, Singh B. Production, characteristics, and biotechnological applications of microbial xylanases. Appl Microbiol Biotechnol 2019; 103:8763-8784. [PMID: 31641815 DOI: 10.1007/s00253-019-10108-6] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Revised: 08/09/2019] [Accepted: 08/28/2019] [Indexed: 01/29/2023]
Abstract
Microbial xylanases have gathered great attention due to their biotechnological potential at industrial scale for many processes. A variety of lignocellulosic materials, such as sugarcane bagasse, rice straw, rice bran, wheat straw, wheat bran, corn cob, and ragi bran, are used for xylanase production which also solved the great issue of solid waste management. Both solid-state and submerged fermentation have been used for xylanase production controlled by various physical and nutritional parameters. Majority of xylanases have optimum pH in the range of 4.0-9.0 with optimum temperature at 30-60 °C. For biochemical, molecular studies and also for successful application in industries, purification and characterization of xylanase have been carried out using various appropriate techniques. Cloning and genetic engineering are used for commercial-level production of xylanase, to meet specific economic viability and industrial needs. Microbial xylanases are used in various biotechnological applications like biofuel production, pulp and paper industry, baking and brewing industry, food and feed industry, and deinking of waste paper. This review describes production, characteristics, and biotechnological applications of microbial xylanases.
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Affiliation(s)
- Alokika
- Laboratory of Bioprocess Technology, Department of Microbiology, Maharshi Dayanand University, Rohtak, Haryana, 124001, India
| | - Bijender Singh
- Laboratory of Bioprocess Technology, Department of Microbiology, Maharshi Dayanand University, Rohtak, Haryana, 124001, India. .,Department of Biotechnology, School of Interdisciplinary and Applied Life Sciences, Central University of Haryana, Jant-Pali, Mahendergarh, Haryana, 123031, India.
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15
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Synergistic effects between the additions of a disulphide bridge and an N-terminal hydrophobic sidechain on the binding pocket tilting and enhanced Xyn11A activity. Arch Biochem Biophys 2019; 672:108068. [DOI: 10.1016/j.abb.2019.108068] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Revised: 07/20/2019] [Accepted: 08/07/2019] [Indexed: 11/22/2022]
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16
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Xiong K, Hou J, Jiang Y, Li X, Teng C, Li Q, Fan G, Yang R, Zhang C. Mutagenesis of N-terminal residues confer thermostability on a Penicillium janthinellum MA21601 xylanase. BMC Biotechnol 2019; 19:51. [PMID: 31345213 PMCID: PMC6659274 DOI: 10.1186/s12896-019-0541-7] [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: 04/12/2019] [Accepted: 07/05/2019] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND A mesophilic xylanase PjxA from Penicillium janthinellum MA21601 has high specific activity under acidic condition and holds great potential for applications in the animal feed industry. To enhance the thermostability of xylanase PjxA, two mutation strategies in the N-terminal region were examined and then integrated into the xylanase to further improvement. The recombinant xylanase PTxA-DB (The meaning of DB is disulfide-bridge.) was constructed by replacement of five residues in the mutated region in TfxA (T10Y, N11H, N12D, Y15F, N30 L), combined with an additional disulfide bridge in the N-terminal region. RESULTS The Tm value of mutant PTxA-DB was improved from 21.3 °C to 76.6 °C, and its half-life was found to be 53.6 min at 60 °C, 107-fold higher than the wild type strain. The location of the disulfide bridge (T2C-T29C) was between the irregular loop and the β-strand A2, accounting for most of the improvement in thermostability of PjxA. Further analysis indicated T2C, T29C, N30 L and Y15F lead to increase N-terminal hydrophobicity. Moreover, the specific activity and substrate affinity of PTxA-DB were also enhanced under the acidic pH values. CONCLUSIONS These results indicated PTxA-DB could be a prospective additive to industrial animal feeds.
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Affiliation(s)
- Ke Xiong
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, Beijing Technology and Business University, No 11 Fucheng Street, Haidian District, Beijing, 100084, China.,Beijing Engineering and Technology Research Center of Food Additives, Beijing Technology and Business University, No 11 Fucheng Street, Haidian District, Beijing, 100084, China.,Beijing Key Laboratory of Flavor Chemistry, Beijing Technology and Business University, No 11 Fucheng Street, Haidian District, Beijing, 100084, China
| | - Jie Hou
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, Beijing Technology and Business University, No 11 Fucheng Street, Haidian District, Beijing, 100084, China.,Beijing Engineering and Technology Research Center of Food Additives, Beijing Technology and Business University, No 11 Fucheng Street, Haidian District, Beijing, 100084, China
| | - Yuefeng Jiang
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, Beijing Technology and Business University, No 11 Fucheng Street, Haidian District, Beijing, 100084, China.,Beijing Engineering and Technology Research Center of Food Additives, Beijing Technology and Business University, No 11 Fucheng Street, Haidian District, Beijing, 100084, China
| | - Xiuting Li
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, Beijing Technology and Business University, No 11 Fucheng Street, Haidian District, Beijing, 100084, China. .,Beijing Engineering and Technology Research Center of Food Additives, Beijing Technology and Business University, No 11 Fucheng Street, Haidian District, Beijing, 100084, China. .,Beijing Key Laboratory of Flavor Chemistry, Beijing Technology and Business University, No 11 Fucheng Street, Haidian District, Beijing, 100084, China.
| | - Chao Teng
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, Beijing Technology and Business University, No 11 Fucheng Street, Haidian District, Beijing, 100084, China.,Beijing Engineering and Technology Research Center of Food Additives, Beijing Technology and Business University, No 11 Fucheng Street, Haidian District, Beijing, 100084, China
| | - Qin Li
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, Beijing Technology and Business University, No 11 Fucheng Street, Haidian District, Beijing, 100084, China.,Beijing Engineering and Technology Research Center of Food Additives, Beijing Technology and Business University, No 11 Fucheng Street, Haidian District, Beijing, 100084, China
| | - Guangsen Fan
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, Beijing Technology and Business University, No 11 Fucheng Street, Haidian District, Beijing, 100084, China.,School of Food and Chemical Engineering, Beijing Technology and Business University, Beijing, 100048, China
| | - Ran Yang
- Beijing Engineering and Technology Research Center of Food Additives, Beijing Technology and Business University, No 11 Fucheng Street, Haidian District, Beijing, 100084, China.,Beijing Key Laboratory of Flavor Chemistry, Beijing Technology and Business University, No 11 Fucheng Street, Haidian District, Beijing, 100084, China.,School of Food and Chemical Engineering, Beijing Technology and Business University, Beijing, 100048, China
| | - Chengnan Zhang
- Beijing Engineering and Technology Research Center of Food Additives, Beijing Technology and Business University, No 11 Fucheng Street, Haidian District, Beijing, 100084, China.,Beijing Key Laboratory of Flavor Chemistry, Beijing Technology and Business University, No 11 Fucheng Street, Haidian District, Beijing, 100084, China.,School of Food and Chemical Engineering, Beijing Technology and Business University, Beijing, 100048, China
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17
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Improving the thermostability and catalytic efficiency of GH11 xylanase PjxA by adding disulfide bridges. Int J Biol Macromol 2019; 128:354-362. [DOI: 10.1016/j.ijbiomac.2019.01.087] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Revised: 01/17/2019] [Accepted: 01/19/2019] [Indexed: 11/24/2022]
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18
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Optimization of cell culture and cell disruption processes to enhance the production of thermophilic cellulase FnCel5A in E.coli using response surface methodology. PLoS One 2019; 14:e0210595. [PMID: 30653549 PMCID: PMC6336418 DOI: 10.1371/journal.pone.0210595] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2018] [Accepted: 12/28/2018] [Indexed: 12/31/2022] Open
Abstract
FnCel5A from Fervidobacterium nodosum is one of the most thermostable endoglucanases that have phenomenal characteristics, such as high activity, pH stability, and multi-specificity towards various substrates. However, large-scale thermophilic enzyme production is still a challenge. Herein, we focus on an optimization approach based on response surface methodology to improve the production of this enzyme. First, a Box-Behnken design was used to examine physiochemical parameters such as induction temperatures, isopropylβ-D-1-thiogalactopyranoside concentrations and induction times on the heterogeneous expression of FnCel5A gene in E. coli. The best culture was collected after adding 0.56 mM IPTG and incubating it for 29.5 h at 24°C. The highest enzymatic activity observed was 3.31 IU/mL. Second, an economical "thermolysis" cell lysis method for the liberation of the enzymes was also optimized using Box-Behnken design. The optimal levels of the variables were temperature 77°C, pH 7.71, and incubation time of 20 min, which gave about 74.3% higher activity than the well-established bead-milling cell disruption method. The maximum productivity of FnCel5A achieved (5772 IU/L) illustrated that its production increased significantly after combining both optimal models. This strategy can be scaled-up readily for overproduction of FnCel5A from recombinant E.coli to facilitate its usage in biomass energy production.
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19
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Effect of disulfide bridge on hydrolytic characteristics of xylanase from Penicillium janthinellum. Int J Biol Macromol 2018; 120:405-413. [PMID: 30145159 DOI: 10.1016/j.ijbiomac.2018.08.099] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Revised: 07/02/2018] [Accepted: 08/21/2018] [Indexed: 11/20/2022]
Abstract
Highly efficient and stable enzymes are required for application in biotechnology, to meet the technical, environmental, and economic industrial demands. Xylanases are hemicellulolytic enzymes that degrade the heteroxylan constituent of the lignocellulosic plant cell wall. In this study, an acidic xylanase designated Pjxyn (pH 4.0) from Penicillium janthinellum was engineered by the introduction of a disulfide bridge. This strategy exploited the influence of the bridge on hydrolysis characteristics and enhanced hydrolysis was achieved. Three mutants [PjxynS(27)S(39), PjxynS(27)S(186), and PjxynS(39)S(186)] produced more xylose and xylobiose as hydrolysis products compared with the wild-type Pjxyn, when commercial xylans and lab-prepared water-insoluble corncob-xylan were used as the substrates, especial for the PjxynS(27)S(39) mutant, the content of xylose and xylobiose was 87.62% (using beechwood xylan) and 69.91% (using oat-spelt xylan) higher than that in the hydrolysis products of Pjxyn. Moreover, each mutant combined with the xylanase mutant T-XynFM effectively decreased the production of xylose with an optimum xylobiose yield. The findings demonstrate the potential industrial value of engineering xylanase to improve its hydrolytic properties and thermostability.
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20
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Suzuki K, Michikawa M, Sato H, Yuki M, Kamino K, Ogasawara W, Fushinobu S, Kaneko S. Purification, Cloning, Functional Expression, Structure, and Characterization of a Thermostable β-Mannanase from Talaromyces trachyspermus B168 and Its Efficiency in Production of Mannooligosaccharides from Coffee Wastes. J Appl Glycosci (1999) 2018; 65:13-21. [PMID: 34354508 PMCID: PMC8056896 DOI: 10.5458/jag.jag.jag-2017_018] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Accepted: 12/27/2017] [Indexed: 11/16/2022] Open
Abstract
Highly thermostable β-mannanase, belonging to glycoside hydrolase family 5 subfamily 7, was purified from the culture supernatant of Talaromyces trachyspermus B168 and the cDNA of its transcript was cloned. The recombinant enzyme showed maximal activity at pH 4.5 and 85 °C. It retained more than 90 % of its activity below 60 °C. Obtaining the crystal structure of the enzyme helped us to understand the mechanism of its thermostability. An antiparallel β-sheet, salt-bridges, hydrophobic packing, proline residues in the loops, and loop shortening are considered to be related to the thermostability of the enzyme. The enzyme hydrolyzed mannans such as locust bean gum, carob galactomannan, guar gum, konjac glucomannan, and ivory nut mannan. It hydrolyzed 50.7 % of the total mannans from coffee waste, producing mannooligosaccharides. The enzyme has the highest optimum temperature among the known fungal β-mannanases and has potential for use in industrial applications.
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Affiliation(s)
| | - Mari Michikawa
- 2 Food Biotechnology Division, National Food Research Institute
| | - Haruna Sato
- 3 Department of Bioengineering, Nagaoka University of Technology
| | - Masahiro Yuki
- 3 Department of Bioengineering, Nagaoka University of Technology
| | - Kei Kamino
- 4 Department of Biotechnology, National Institute of Technology and Evaluation
| | - Wataru Ogasawara
- 3 Department of Bioengineering, Nagaoka University of Technology
| | | | - Satoshi Kaneko
- 2 Food Biotechnology Division, National Food Research Institute.,5 Department of Subtropical Biochemistry and Biotechnology, Faculty of Agriculture, University of the Ryukyus
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21
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Production and characterization of a novel acidophilic and thermostable xylanase from Thermoascus aurantiacu. Int J Biol Macromol 2018; 109:1270-1279. [DOI: 10.1016/j.ijbiomac.2017.11.130] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2017] [Revised: 11/16/2017] [Accepted: 11/20/2017] [Indexed: 01/24/2023]
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22
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Engineering improved thermostability of the GH11 xylanase from Neocallimastix patriciarum via computational library design. Appl Microbiol Biotechnol 2018; 102:3675-3685. [DOI: 10.1007/s00253-018-8872-1] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2017] [Revised: 02/12/2018] [Accepted: 02/13/2018] [Indexed: 12/26/2022]
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23
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Exploring the aglycone subsite of a GH11 xylanase for the synthesis of xylosides by transglycosylation reactions. J Biotechnol 2018; 272-273:56-63. [PMID: 29501471 DOI: 10.1016/j.jbiotec.2018.02.013] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Revised: 02/18/2018] [Accepted: 02/27/2018] [Indexed: 11/22/2022]
Abstract
Xylanases Tx-xyn10 and Tx-xyn11 were compared for their transxylosylation abilities in the presence of various acceptors. Tx-xyn10 exhibited a broad specificity for various acceptors, whereas xylanase Tx-xyn11 catalysed transxylosylation reactions only in presence of polyphenolic acceptors. A modelling approach was developed to study the molecular bottlenecks into the active site of the enzyme that could be responsible for this restricted specificity. The glycosyl-enzyme intermediate of Tx-xyn11 was modelled, and a rotamer of the Y78 residue was integrated. In silico mutations of some residues from the (+1) and (+2) subsites were tested for the deglycosylation step in the presence of non-polyphenolic acceptors. The results indicated that the mutant W126A was able to use aliphatic alcohols and benzyl alcohol as acceptors for transxylosylation. Experimental validation was tested by mutating the xylanase Tx-xyn11 at position W126 into alanine. The specific activity and catalytic efficiency of the W126A mutant during the hydrolysis of xylans decreased by 2-fold and 4-fold, respectively, compared to wild-type xylanase. Among tested acceptors, transxylosylation catalysed by mutant W126A was improved with benzyl alcohol leading to a 2-fold higher concentration of benzyl xylobioside, as predicted by in silico mutation. This improved transxylosylation in the presence of benzyl alcohol leading to higher synthesis of benzyl xylobioside could likely be explained by lowest steric hindrance in the aglycone subsite of the mutated xylanase. No secondary hydrolysis of benzyl xylobioside occurred for both wild-type and mutant xylanases. Finally, our results demonstrated that the modelling approach was limited and that accounting for protein dynamics can lead to improved models.
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24
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Tanghe M, Danneels B, Last M, Beerens K, Stals I, Desmet T. Disulfide bridges as essential elements for the thermostability of lytic polysaccharide monooxygenase LPMO10C from Streptomyces coelicolor. Protein Eng Des Sel 2017; 30:401-408. [PMID: 28338903 DOI: 10.1093/protein/gzx014] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Accepted: 02/20/2017] [Indexed: 12/17/2022] Open
Abstract
Lytic polysaccharide monooxygenases (LPMOs) are crucial components of cellulase mixtures but their stability has not yet been studied in detail, let alone been engineered for industrial applications. In this work, we have evaluated the importance of disulfide bridges for the thermodynamic stability of Streptomyces coelicolor LPMO10C. Interestingly, this enzyme was found to retain 34% of its activity after 2-h incubation at 80°C while its apparent melting temperature (Tm) is only 51°C. When its three disulfide bridges were broken, however, irreversible unfolding occurred and no residual activity could be detected after a similar heat treatment. Based on these findings, additional disulfide bridges were introduced, as predicted by computational tools (MOdelling of DIsulfide bridges in Proteins (MODiP) and Disulfide by Design (DbD)) and using the most flexible positions in the structure as target sites. Four out of 16 variants displayed an improvement in Tm, ranging from 2 to 9°C. Combining the positive mutations yielded additional improvements (up to 19°C) but aberrant unfolding patterns became apparent in some cases, resulting in a diminished capacity for heat resistance. Nonetheless, the best variant, a combination of A143C-P183C and S73C-A115C, displayed a 12°C increase in Tm and was able to retain and was able to retain no less than 60% of its activity after heat treatment.
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Affiliation(s)
- Magali Tanghe
- Centre for Synthetic Biology (CSB), Department of Biochemical and Microbial Technology, Ghent University, Coupure Links 653, B-9000 Ghent, Belgium
| | - Barbara Danneels
- Centre for Synthetic Biology (CSB), Department of Biochemical and Microbial Technology, Ghent University, Coupure Links 653, B-9000 Ghent, Belgium
| | - Matthias Last
- Centre for Synthetic Biology (CSB), Department of Biochemical and Microbial Technology, Ghent University, Coupure Links 653, B-9000 Ghent, Belgium
| | - Koen Beerens
- Centre for Synthetic Biology (CSB), Department of Biochemical and Microbial Technology, Ghent University, Coupure Links 653, B-9000 Ghent, Belgium
| | - Ingeborg Stals
- Industrial Catalysis and Adsorption Technology (INCAT), Faculty of Engineering and Architecture, Ghent University, Valentin Vaerwyckweg 1, B-9000 Ghent, Belgium
| | - Tom Desmet
- Centre for Synthetic Biology (CSB), Department of Biochemical and Microbial Technology, Ghent University, Coupure Links 653, B-9000 Ghent, Belgium
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25
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Lemos LN, Pereira RV, Quaggio RB, Martins LF, Moura LMS, da Silva AR, Antunes LP, da Silva AM, Setubal JC. Genome-Centric Analysis of a Thermophilic and Cellulolytic Bacterial Consortium Derived from Composting. Front Microbiol 2017; 8:644. [PMID: 28469608 PMCID: PMC5395642 DOI: 10.3389/fmicb.2017.00644] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Accepted: 03/29/2017] [Indexed: 11/22/2022] Open
Abstract
Microbial consortia selected from complex lignocellulolytic microbial communities are promising alternatives to deconstruct plant waste, since synergistic action of different enzymes is required for full degradation of plant biomass in biorefining applications. Culture enrichment also facilitates the study of interactions among consortium members, and can be a good source of novel microbial species. Here, we used a sample from a plant waste composting operation in the São Paulo Zoo (Brazil) as inoculum to obtain a thermophilic aerobic consortium enriched through multiple passages at 60°C in carboxymethylcellulose as sole carbon source. The microbial community composition of this consortium was investigated by shotgun metagenomics and genome-centric analysis. Six near-complete (over 90%) genomes were reconstructed. Similarity and phylogenetic analyses show that four of these six genomes are novel, with the following hypothesized identifications: a new Thermobacillus species; the first Bacillus thermozeamaize genome (for which currently only 16S sequences are available) or else the first representative of a new family in the Bacillales order; the first representative of a new genus in the Paenibacillaceae family; and the first representative of a new deep-branching family in the Clostridia class. The reconstructed genomes from known species were identified as Geobacillus thermoglucosidasius and Caldibacillus debilis. The metabolic potential of these recovered genomes based on COG and CAZy analyses show that these genomes encode several glycoside hydrolases (GHs) as well as other genes related to lignocellulose breakdown. The new Thermobacillus species stands out for being the richest in diversity and abundance of GHs, possessing the greatest potential for biomass degradation among the six recovered genomes. We also investigated the presence and activity of the organisms corresponding to these genomes in the composting operation from which the consortium was built, using compost metagenome and metatranscriptome datasets generated in a previous study. We obtained strong evidence that five of the six recovered genomes are indeed present and active in that composting process. We have thus discovered three (perhaps four) new thermophillic bacterial species that add to the increasing repertoire of known lignocellulose degraders, whose biotechnological potential can now be investigated in further studies.
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Affiliation(s)
- Leandro N Lemos
- Departamento de Bioquímica, Instituto de Química, Universidade de São PauloSão Paulo, Brazil.,Programa de Pós-Graduação Interunidades em Bioinformática, Universidade de São PauloSão Paulo, Brazil
| | - Roberta V Pereira
- Departamento de Bioquímica, Instituto de Química, Universidade de São PauloSão Paulo, Brazil
| | - Ronaldo B Quaggio
- Departamento de Bioquímica, Instituto de Química, Universidade de São PauloSão Paulo, Brazil
| | - Layla F Martins
- Departamento de Bioquímica, Instituto de Química, Universidade de São PauloSão Paulo, Brazil
| | - Livia M S Moura
- Departamento de Bioquímica, Instituto de Química, Universidade de São PauloSão Paulo, Brazil.,Programa de Pós-Graduação Interunidades em Bioinformática, Universidade de São PauloSão Paulo, Brazil
| | - Amanda R da Silva
- Departamento de Bioquímica, Instituto de Química, Universidade de São PauloSão Paulo, Brazil.,Programa de Pós-Graduação Interunidades em Bioinformática, Universidade de São PauloSão Paulo, Brazil
| | - Luciana P Antunes
- Departamento de Bioquímica, Instituto de Química, Universidade de São PauloSão Paulo, Brazil
| | - Aline M da Silva
- Departamento de Bioquímica, Instituto de Química, Universidade de São PauloSão Paulo, Brazil
| | - João C Setubal
- Departamento de Bioquímica, Instituto de Química, Universidade de São PauloSão Paulo, Brazil.,Biocomplexity Institute, Virginia TechBlacksburg, VA, USA
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26
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Li Q, Sun B, Jia H, Hou J, Yang R, Xiong K, Xu Y, Li X. Engineering a xylanase from Streptomyce rochei L10904 by mutation to improve its catalytic characteristics. Int J Biol Macromol 2017; 101:366-372. [PMID: 28356235 DOI: 10.1016/j.ijbiomac.2017.03.135] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Revised: 03/21/2017] [Accepted: 03/24/2017] [Indexed: 11/18/2022]
Abstract
Protein engineering was performed by N-terminal region replacement and site-directed mutagenesis in the cord of a xylanase (Srxyn) from Streptomyce rochei L10904 to improve its catalytic characteristics. Three mutants SrxynF, SrxynM and SrxynFM displayed 2.1-fold, 3.2-fold and 5.3-fold higher specific activities than that of Srxyn, respectively. Moreover, all of the mutants showed greater substrate affinity and kcat/Km than the native Srxyn. In addition, the enzymes showed improved hydrolysis characteristics, of which the most noteworthy is the enhanced ability of producing xylobiose (X2) and xylotriose (X3) from polymeric substrates. The engineered xylanases have greater potential for applications in oligosaccharide preparation industry.
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Affiliation(s)
- Qin Li
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, Beijing Technology and Business University (BTBU), Beijing 100048, China; School of Food and Chemical Engineering, Beijing Technology and Business University, No.33, Fucheng Road, Beijing 100048, China
| | - Baoguo Sun
- School of Food and Chemical Engineering, Beijing Technology and Business University, No.33, Fucheng Road, Beijing 100048, China; Beijing Engineering and Technology Research Center of Food Additives, Beijing Technology and Business University (BTBU), Beijing 100048, China
| | - Huiyong Jia
- Department of Biology, Emory University, 1510 Clifton Road, Atlanta, GA 30322, USA
| | - Jie Hou
- School of Food and Chemical Engineering, Beijing Technology and Business University, No.33, Fucheng Road, Beijing 100048, China
| | - Ran Yang
- School of Food and Chemical Engineering, Beijing Technology and Business University, No.33, Fucheng Road, Beijing 100048, China
| | - Ke Xiong
- School of Food and Chemical Engineering, Beijing Technology and Business University, No.33, Fucheng Road, Beijing 100048, China
| | - Youqiang Xu
- Beijing Engineering and Technology Research Center of Food Additives, Beijing Technology and Business University (BTBU), Beijing 100048, China
| | - Xiuting Li
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, Beijing Technology and Business University (BTBU), Beijing 100048, China; School of Food and Chemical Engineering, Beijing Technology and Business University, No.33, Fucheng Road, Beijing 100048, China.
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27
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Improving special hydrolysis characterization into Talaromyces thermophilus F1208 xylanase by engineering of N-terminal extension and site-directed mutagenesis in C-terminal. Int J Biol Macromol 2017; 96:451-458. [DOI: 10.1016/j.ijbiomac.2016.12.050] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2016] [Revised: 12/16/2016] [Accepted: 12/17/2016] [Indexed: 11/22/2022]
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28
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Thermus thermophilus as source of thermozymes for biotechnological applications: homologous expression and biochemical characterization of an α-galactosidase. Microb Cell Fact 2017; 16:28. [PMID: 28193276 PMCID: PMC5307791 DOI: 10.1186/s12934-017-0638-4] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Accepted: 01/25/2017] [Indexed: 11/17/2022] Open
Abstract
Background The genus Thermus, which has been considered for a long time as a fruitful source of biotechnological relevant enzymes, has emerged more recently as suitable host to overproduce thermozymes. Among these, α-galactosidases are widely used in several industrial bioprocesses that require high working temperatures and for which thermostable variants offer considerable advantages over their thermolabile counterparts. Results Thermus thermophilus HB27 strain was used for the homologous expression of the TTP0072 gene encoding for an α-galactosidase (TtGalA). Interestingly, a soluble and active histidine-tagged enzyme was produced in larger amounts (5 mg/L) in this thermophilic host than in Escherichia coli (0.5 mg/L). The purified recombinant enzyme showed an optimal activity at 90 °C and retained more than 40% of activity over a broad range of pH (from 5 to 8). Conclusions TtGalA is among the most thermoactive and thermostable α-galactosidases discovered so far, thus pointing to T. thermophilus as cell factory for the recombinant production of biocatalysts active at temperature values over 90 °C. Electronic supplementary material The online version of this article (doi:10.1186/s12934-017-0638-4) contains supplementary material, which is available to authorized users.
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Zhou CY, Li TB, Wang YT, Zhu XS, Kang J. Exploration of a N-terminal disulfide bridge to improve the thermostability of a GH11 xylanase from Aspergillus niger. J GEN APPL MICROBIOL 2016; 62:83-9. [DOI: 10.2323/jgam.62.83] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Chen-Yan Zhou
- School of Life Science and Technology, Xinxiang Medical University
| | - Tong-Biao Li
- School of Life Science and Technology, Xinxiang Medical University
| | - Yong-Tao Wang
- The First Affiliated Hospital, Xinxiang Medical University
| | - Xin-Shu Zhu
- School of Life Science and Technology, Xinxiang Medical University
| | - Jing Kang
- School of Life Science and Technology, Xinxiang Medical University
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White biotechnology: State of the art strategies for the development of biocatalysts for biorefining. Biotechnol Adv 2015; 33:1653-70. [PMID: 26303096 DOI: 10.1016/j.biotechadv.2015.08.004] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Revised: 07/31/2015] [Accepted: 08/17/2015] [Indexed: 12/31/2022]
Abstract
White biotechnology is a term that is now often used to describe the implementation of biotechnology in the industrial sphere. Biocatalysts (enzymes and microorganisms) are the key tools of white biotechnology, which is considered to be one of the key technological drivers for the growing bioeconomy. Biocatalysts are already present in sectors such as the chemical and agro-food industries, and are used to manufacture products as diverse as antibiotics, paper pulp, bread or advanced polymers. This review proposes an original and global overview of highly complementary fields of biotechnology at both enzyme and microorganism level. A certain number of state of the art approaches that are now being used to improve the industrial fitness of biocatalysts particularly focused on the biorefinery sector are presented. The first part deals with the technologies that underpin the development of industrial biocatalysts, notably the discovery of new enzymes and enzyme improvement using directed evolution techniques. The second part describes the toolbox available by the cell engineer to shape the metabolism of microorganisms. And finally the last part focuses on the 'omic' technologies that are vital for understanding and guide microbial engineering toward more efficient microbial biocatalysts. Altogether, these techniques and strategies will undoubtedly help to achieve the challenging task of developing consolidated bioprocessing (i.e. CBP) readily available for industrial purpose.
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Cheng YS, Chen CC, Huang JW, Ko TP, Huang Z, Guo RT. Improving the catalytic performance of a GH11 xylanase by rational protein engineering. Appl Microbiol Biotechnol 2015; 99:9503-10. [DOI: 10.1007/s00253-015-6712-0] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Revised: 05/18/2015] [Accepted: 05/21/2015] [Indexed: 11/28/2022]
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Bhalla A, Bischoff KM, Sani RK. Highly Thermostable Xylanase Production from A Thermophilic Geobacillus sp. Strain WSUCF1 Utilizing Lignocellulosic Biomass. Front Bioeng Biotechnol 2015; 3:84. [PMID: 26137456 PMCID: PMC4468944 DOI: 10.3389/fbioe.2015.00084] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Accepted: 05/22/2015] [Indexed: 01/04/2023] Open
Abstract
Efficient enzymatic hydrolysis of lignocellulose to fermentable sugars requires a complete repertoire of biomass deconstruction enzymes. Hemicellulases play an important role in hydrolyzing hemicellulose component of lignocellulose to xylooligosaccharides and xylose. Thermostable xylanases have been a focus of attention as industrially important enzymes due to their long shelf life at high temperatures. Geobacillus sp. strain WSUCF1 produced thermostable xylanase activity (crude xylanase cocktail) when grown on xylan or various inexpensive untreated and pretreated lignocellulosic biomasses such as prairie cord grass and corn stover. The optimum pH and temperature for the crude xylanase cocktail were 6.5 and 70°C, respectively. The WSUCF1 crude xylanase was found to be highly thermostable with half-lives of 18 and 12 days at 60 and 70°C, respectively. At 70°C, rates of xylan hydrolysis were also found to be better with the WSUCF1 secretome than those with commercial enzymes, i.e., for WSUCF1 crude xylanase, Cellic-HTec2, and AccelleraseXY, the percent xylan conversions were 68.9, 49.4, and 28.92, respectively. To the best of our knowledge, WSUCF1 crude xylanase cocktail is among the most thermostable xylanases produced by thermophilic Geobacillus spp. and other thermophilic microbes (optimum growth temperature ≤70°C). High thermostability, activity over wide range of temperatures, and better xylan hydrolysis than commercial enzymes make WSUCF1 crude xylanase suitable for thermophilic lignocellulose bioconversion processes.
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Affiliation(s)
- Aditya Bhalla
- Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology , Rapid City, SD , USA
| | - Kenneth M Bischoff
- Renewable Product Technology Research Unit, Agricultural Research Service, National Center for Agricultural Utilization Research, U.S. Department of Agriculture , Peoria, IL , USA
| | - Rajesh Kumar Sani
- Department of Chemical and Biological Engineering, South Dakota School of Mines and Technology , Rapid City, SD , USA
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Song L, Tsang A, Sylvestre M. Engineering a thermostable fungal GH10 xylanase, importance of N-terminal amino acids. Biotechnol Bioeng 2015; 112:1081-91. [DOI: 10.1002/bit.25533] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Letian Song
- Institut National de la Recherche Scientifique; INRS-Institut Armand-Frappier; Laval QC H7V 1B7 Canada
| | - Adrian Tsang
- Centre for Structural and Functional Genomics; Concordia University; Sherbrooke Canada
| | - Michel Sylvestre
- Institut National de la Recherche Scientifique; INRS-Institut Armand-Frappier; Laval QC H7V 1B7 Canada
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Quantitative proteomic study of Aspergillus Fumigatus secretome revealed deamidation of secretory enzymes. J Proteomics 2015; 119:154-68. [DOI: 10.1016/j.jprot.2015.02.007] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2014] [Revised: 02/07/2015] [Accepted: 02/15/2015] [Indexed: 01/30/2023]
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Chen CC, Ko TP, Huang JW, Guo RT. Heat- and Alkaline-Stable Xylanases: Application, Protein Structure and Engineering. CHEMBIOENG REVIEWS 2015. [DOI: 10.1002/cben.201400035] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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Joshi S, Satyanarayana T. In vitro engineering of microbial enzymes with multifarious applications: prospects and perspectives. BIORESOURCE TECHNOLOGY 2015; 176:273-283. [PMID: 25435065 DOI: 10.1016/j.biortech.2014.10.151] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2014] [Revised: 10/28/2014] [Accepted: 10/29/2014] [Indexed: 06/04/2023]
Abstract
The discovery of a novel enzyme from a microbial source takes anywhere between months to years, and therefore, there has been an immense interest in modifying the existing microbial enzymes to suit the present day needs of the industry. The redesigning of industrially useful enzymes for improving their performance has become a challenge because bioinformatics databases have been revealing new facts on a day-to-day basis. Modification of the existing enzymes has become a trend for fine tuning of biocatalysts in the biotech industry. Hydrolases are employed in pharmaceutical, biofuel, detergent, food and feed industries that significantly contribute to the global annual revenue, and therefore, the emphasis has been on engineering them. Although a large data is accumulating on making alterations in microbial enzymes, there is a lack of definite information on redesigning industrial enzymes. This review focuses on the recent developments in improving the characteristics of various biotechnologically important enzymes.
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Affiliation(s)
- Swati Joshi
- Department of Microbiology, University of Delhi South Campus, Benito Juarez Road, New Delhi 110 021, India
| | - Tulasi Satyanarayana
- Department of Microbiology, University of Delhi South Campus, Benito Juarez Road, New Delhi 110 021, India.
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Stern J, Anbar M, Moraïs S, Lamed R, Bayer EA. Insights into enhanced thermostability of a cellulosomal enzyme. Carbohydr Res 2014; 389:78-84. [DOI: 10.1016/j.carres.2014.01.014] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Revised: 01/13/2014] [Accepted: 01/17/2014] [Indexed: 10/25/2022]
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Duquesne S, Bozonnet S, Bordes F, Dumon C, Nicaud JM, Marty A. Construction of a highly active xylanase displaying oleaginous yeast: comparison of anchoring systems. PLoS One 2014; 9:e95128. [PMID: 24743311 PMCID: PMC3990623 DOI: 10.1371/journal.pone.0095128] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2013] [Accepted: 03/24/2014] [Indexed: 11/24/2022] Open
Abstract
Three Yarrowia lipolytica cell wall proteins (YlPir, YlCWP1 and YlCBM) were evaluated for their ability to display the xylanase TxXYN from Thermobacillus xylanilyticus on the cell surface of Y. lipolytica. The fusion proteins were produced in Y. lipolytica JMY1212, a strain engineered for mono-copy chromosomal insertion, and enabling accurate comparison of anchoring systems. The construction using YlPir enabled cell bound xylanase activity to be maximised (71.6 U/g). Although 48% of the activity was released in the supernatant, probably due to proteolysis at the fusion zone, this system is three times more efficient for the anchoring of TxXYN than the YlCWP1 system formerly developed for Y. lipolytica. As far as we know it represents the best displayed xylanase activity ever published. It could be an attractive alternative anchoring system to display enzymes in Y. lipolytica.
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Affiliation(s)
- Sophie Duquesne
- Université de Toulouse; INSA, UPS, INP; LISBP, Toulouse, France
- INRA, UMR792 Ingénierie des Systèmes Biologiques et des Procédés, Toulouse, France
- CNRS, UMR5504, Toulouse, France
- * E-mail:
| | - Sophie Bozonnet
- Université de Toulouse; INSA, UPS, INP; LISBP, Toulouse, France
- INRA, UMR792 Ingénierie des Systèmes Biologiques et des Procédés, Toulouse, France
- CNRS, UMR5504, Toulouse, France
| | - Florence Bordes
- Université de Toulouse; INSA, UPS, INP; LISBP, Toulouse, France
- INRA, UMR792 Ingénierie des Systèmes Biologiques et des Procédés, Toulouse, France
- CNRS, UMR5504, Toulouse, France
| | - Claire Dumon
- Université de Toulouse; INSA, UPS, INP; LISBP, Toulouse, France
- INRA, UMR792 Ingénierie des Systèmes Biologiques et des Procédés, Toulouse, France
- CNRS, UMR5504, Toulouse, France
| | - Jean-Marc Nicaud
- INRA, UMR1319 Micalis, Domaine de Vilvert, Jouy-en-Josas, France
- AgroParisTech, UMR Micalis, Jouy-en-Josas, France
| | - Alain Marty
- Université de Toulouse; INSA, UPS, INP; LISBP, Toulouse, France
- INRA, UMR792 Ingénierie des Systèmes Biologiques et des Procédés, Toulouse, France
- CNRS, UMR5504, Toulouse, France
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Zhang S, He Y, Yu H, Dong Z. Seven N-terminal residues of a thermophilic xylanase are sufficient to confer hyperthermostability on its mesophilic counterpart. PLoS One 2014; 9:e87632. [PMID: 24498158 PMCID: PMC3907472 DOI: 10.1371/journal.pone.0087632] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2013] [Accepted: 12/27/2013] [Indexed: 11/18/2022] Open
Abstract
Xylanases, and especially thermostable xylanases, are increasingly of interest for the deconstruction of lignocellulosic biomass. In this paper, the termini of a pair of xylanases, mesophilic SoxB and thermophilic TfxA, were studied. Two regions in the N-terminus of TfxA were discovered to be potentially important for the thermostability. By focusing on Region 4, it was demonstrated that only two mutations, N32G and S33P cooperated to improve the thermostability of mesophilic SoxB. By introducing two potential regions into SoxB in combination, the most thermostable mutant, M2-N32G-S33P, was obtained. The M2-N32G-S33P had a melting temperature (Tm) that was 25.6°C higher than the Tm of SoxB. Moreover, M2-N32G-S33P was even three-fold more stable than TfxA and had a Tm value that was 9°C higher than the Tm of TfxA. Thus, for the first time, the mesophilic SoxB "pupil" outperformed its thermophilic TfxA "master" and acquired hyperthermostability simply by introducing seven thermostabilizing residues from the extreme N-terminus of TfxA. This work suggested that mutations in the extreme N-terminus were sufficient for the mesophilic xylanase SoxB to acquire hyperthermostability.
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Affiliation(s)
- Shan Zhang
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, P. R. China
| | - Yongzhi He
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, P. R. China
| | - Haiying Yu
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, P. R. China
| | - Zhiyang Dong
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, P. R. China
- * E-mail:
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40
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Song L, Dumon C, Siguier B, André I, Eneyskaya E, Kulminskaya A, Bozonnet S, O'Donohue MJ. Impact of an N-terminal extension on the stability and activity of the GH11 xylanase from Thermobacillus xylanilyticus. J Biotechnol 2014; 174:64-72. [PMID: 24440633 DOI: 10.1016/j.jbiotec.2014.01.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2013] [Revised: 12/31/2013] [Accepted: 01/03/2014] [Indexed: 01/26/2023]
Abstract
To understand structure-function relationships in the N-terminal region of GH11 xylanases, the 17 N-terminal amino acids of the GH11 xylanase from Neocallimastix patriciarum (Np-Xyn) have been grafted onto the N-terminal extremity of the untypically short GH11 xylanase from Thermobacillus xylanilyticus (Tx-Xyn), creating a hybrid enzyme denoted NTfus. The hybrid xylanase displayed properties (pH and temperature optima) similar to those of the parental enzyme, although thermostability was lowered, with the Tm value, being reduced by 5°C. Kinetic assays using oNP-Xylo-oligosaccharides (DP2 and 3) indicated that the N-extension did not procure more extensive substrate binding, even when further mutagenesis was performed to promote this. However, these experiments confirmed weak subsite -3 for both NTfus and the parental enzyme. The catalytic efficiency of NTfus was shown to be 17% higher than that of the parental enzyme on low viscosity wheat arabinoxylan and trials using milled wheat straw as the substrate revealed that NTfus released more substituted oligosaccharide products (Xyl/Ara=8.97±0.13 compared to Xyl/Ara=9.70±0.21 for the parental enzyme), suggesting that the hybrid enzyme possesses wider substrate selectivity. Combining either the parental enzyme or NTfus with the cellulolytic cocktail Accellerase 1500 boosted the impact of the latter on wheat straw, procuring yields of solubilized xylose and glucose of 23 and 24% of theoretical yield, respectively, thus underlining the benefits of added xylanase activity when using this cellulase cocktail. Overall, in view of the results obtained for NTfus, we propose that the N-terminal extension leads to the modification of a putative secondary substrate binding site, a hypothesis that is highly consistent with previous data.
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Affiliation(s)
- Letian Song
- Université de Toulouse, INSA,UPS,INP, LISBP, 135 Avenue de Rangueil, F-31077 Toulouse, France; INRA, UMR792 Ingénierie des Systèmes Biologiques et des Procédés, F-31400 Toulouse, France; CNRS, UMR5504, F-31400 Toulouse, France
| | - Claire Dumon
- Université de Toulouse, INSA,UPS,INP, LISBP, 135 Avenue de Rangueil, F-31077 Toulouse, France; INRA, UMR792 Ingénierie des Systèmes Biologiques et des Procédés, F-31400 Toulouse, France; CNRS, UMR5504, F-31400 Toulouse, France
| | - Béatrice Siguier
- Université de Toulouse, INSA,UPS,INP, LISBP, 135 Avenue de Rangueil, F-31077 Toulouse, France; INRA, UMR792 Ingénierie des Systèmes Biologiques et des Procédés, F-31400 Toulouse, France; CNRS, UMR5504, F-31400 Toulouse, France; CNRS, Institut de Pharmacologie et de Biologie Structurale, F-31077 Toulouse, France
| | - Isabelle André
- Université de Toulouse, INSA,UPS,INP, LISBP, 135 Avenue de Rangueil, F-31077 Toulouse, France; INRA, UMR792 Ingénierie des Systèmes Biologiques et des Procédés, F-31400 Toulouse, France; CNRS, UMR5504, F-31400 Toulouse, France
| | - Elena Eneyskaya
- National Research Center "Kurchatov Institute", B.P. Konstantinov Petersburg Nuclear Physics Institute, Gatchina, 188350 St. Petersburg, Russia
| | - Anna Kulminskaya
- National Research Center "Kurchatov Institute", B.P. Konstantinov Petersburg Nuclear Physics Institute, Gatchina, 188350 St. Petersburg, Russia
| | - Sophie Bozonnet
- Université de Toulouse, INSA,UPS,INP, LISBP, 135 Avenue de Rangueil, F-31077 Toulouse, France; INRA, UMR792 Ingénierie des Systèmes Biologiques et des Procédés, F-31400 Toulouse, France; CNRS, UMR5504, F-31400 Toulouse, France
| | - Michael Joseph O'Donohue
- Université de Toulouse, INSA,UPS,INP, LISBP, 135 Avenue de Rangueil, F-31077 Toulouse, France; INRA, UMR792 Ingénierie des Systèmes Biologiques et des Procédés, F-31400 Toulouse, France; CNRS, UMR5504, F-31400 Toulouse, France.
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Satyanarayana DVT. Improvement in thermostability of metagenomic GH11 endoxylanase (Mxyl) by site-directed mutagenesis and its applicability in paper pulp bleaching process. J Ind Microbiol Biotechnol 2013; 40:1373-81. [PMID: 24100791 DOI: 10.1007/s10295-013-1347-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2013] [Accepted: 09/12/2013] [Indexed: 11/28/2022]
Abstract
An attempt has been made for enhancing the thermostability of xylanase (Mxyl) retrieved from a compost-soil-based metagenomic library. The analysis of the structure of xylanase by molecular dynamics simulation revealed more structural fluctuations in β-sheets. When the surface of β-sheets was enriched with arginine residues by substituting serine/threonine by site-directed mutagenesis, the enzyme with four arginine substitutions (MxylM4) exhibited enhanced thermostability at 80 °C. The T 1/2 of MxylM4 at 80 °C, in the presence of birchwood xylan, increased from 130 to 150 min at 80 °C without any alteration in optimum pH and temperature and molecular mass. Improvement in thermostability of MxylM4 was corroborated by increase in T m by 6 °C over that of Mxyl. The K m of MxylM4, however, increased from 8.01 ± 0.56 of Mxyl to 12.5 ± 0.32 mg ml(-1), suggesting a decrease in the affinity as well as specific enzyme activity. The Mxyl as well as MxylM4 liberated chromophores and lignin-derived compounds from kraft pulp, indicating their applicability in pulp bleaching.
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Adav SS, Ravindran A, Sze SK. Proteomic analysis of temperature dependent extracellular proteins from Aspergillus fumigatus grown under solid-state culture condition. J Proteome Res 2013; 12:2715-31. [PMID: 23647126 DOI: 10.1021/pr4000762] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Fungal species of the genus Aspergillus are filamentous ubiquitous saprophytes that play a major role in lignocellulosic biomass recycling and also are considered as cell factories for the production of organic acids, pharmaceuticals, and industrially important enzymes. Analysis of extracellular secreted biomass degrading enzymes using complex lignocellulosic biomass as a substrate by solid-state fermentation could be a more practical approach to evaluate application of the enzymes for lignocellulosic biorefinery. This study isolated a fungal strain from compost, identified as Aspergillus fumigatus, and further analyzed it for lignocellulolytic enzymes at different temperatures using label free quantitative proteomics. The profile of secretome composition discovered cellulases, hemicellulases, lignin degrading proteins, peptidases and proteases, and transport and hypothetical proteins; while protein abundances and further their hierarchical clustering analysis revealed temperature dependent expression of these enzymes during solid-state fermentation of sawdust. The enzyme activities and protein abundances as determined by exponentially modified protein abundance index (emPAI) indicated the maximum activities at the range of 40-50 °C, demonstrating the thermophilic nature of the isolate A. fumigatus LF9. Characterization of the thermostability of secretome suggested the potential of the isolated fungal strain in the production of thermophilic biomass degrading enzymes for industrial application.
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Affiliation(s)
- Sunil S Adav
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore 637551.
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43
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Khan S, Lindahl S, Turner C, Karlsson EN. Immobilization of thermostable β-glucosidase variants on acrylic supports for biocatalytic processes in hot water. ACTA ACUST UNITED AC 2012. [DOI: 10.1016/j.molcatb.2012.01.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Paës G, Cortés J, Siméon T, O'Donohue MJ, Tran V. Thumb-loops up for catalysis: a structure/function investigation of a functional loop movement in a GH11 xylanase. Comput Struct Biotechnol J 2012; 1:e201207001. [PMID: 24688637 PMCID: PMC3962102 DOI: 10.5936/csbj.201207001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2012] [Revised: 05/23/2012] [Accepted: 05/27/2012] [Indexed: 12/17/2022] Open
Abstract
Dynamics is a key feature of enzyme catalysis. Unfortunately, current experimental and computational techniques do not yet provide a comprehensive understanding and description of functional macromolecular motions. In this work, we have extended a novel computational technique, which combines molecular modeling methods and robotics algorithms, to investigate functional motions of protein loops. This new approach has been applied to study the functional importance of the so-called thumb-loop in the glycoside hydrolase family 11 xylanase from Thermobacillus xylanilyticus (Tx-xyl). The results obtained provide new insight into the role of the loop in the glycosylation/deglycosylation catalytic cycle, and underline the key importance of the nature of the residue located at the tip of the thumb-loop. The effect of mutations predicted in silico has been validated by in vitro site-directed mutagenesis experiments. Overall, we propose a comprehensive model of Tx-xyl catalysis in terms of substrate and product dynamics by identifying the action of the thumb-loop motion during catalysis.
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Affiliation(s)
- Gabriel Paës
- CNRS, FRE3478 UFIP, Faculté des Sciences et des Techniques, 2 rue de la Houssinière, F-44322 Nantes, France ; University of Nantes, FRE3478 UFIP, Faculté des Sciences et des Techniques, 2 rue de la Houssinière, F-44322 Nantes, France ; INRA, UMR614 FARE, 2 esplanade Roland Garros, F-51686 Reims, France ; University of Reims Champagne-Ardenne, UMR614 FARE, 2 esplanade Roland Garros, F-51686 Reims, France
| | - Juan Cortés
- CNRS, LAAS, 7 avenue du colonel Roche, F-31400 Toulouse, France ; University of Toulouse, LAAS, F-31400 Toulouse, France
| | - Thierry Siméon
- CNRS, LAAS, 7 avenue du colonel Roche, F-31400 Toulouse, France ; University of Toulouse, LAAS, F-31400 Toulouse, France
| | - Michael J O'Donohue
- INRA, UMR614 FARE, 2 esplanade Roland Garros, F-51686 Reims, France ; University of Reims Champagne-Ardenne, UMR614 FARE, 2 esplanade Roland Garros, F-51686 Reims, France ; INRA, UMR792 LISBP, 137 avenue de Rangueil, F-31077 Toulouse, France ; INSA, UMR792 LISBP, 137 avenue de Rangueil, F-31077 Toulouse, France
| | - Vinh Tran
- CNRS, FRE3478 UFIP, Faculté des Sciences et des Techniques, 2 rue de la Houssinière, F-44322 Nantes, France ; University of Nantes, FRE3478 UFIP, Faculté des Sciences et des Techniques, 2 rue de la Houssinière, F-44322 Nantes, France
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Wang Y, Fu Z, Huang H, Zhang H, Yao B, Xiong H, Turunen O. Improved thermal performance of Thermomyces lanuginosus GH11 xylanase by engineering of an N-terminal disulfide bridge. BIORESOURCE TECHNOLOGY 2012; 112:275-279. [PMID: 22425398 DOI: 10.1016/j.biortech.2012.02.092] [Citation(s) in RCA: 77] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2011] [Revised: 02/15/2012] [Accepted: 02/17/2012] [Indexed: 05/31/2023]
Abstract
In order to increase the stability of thermophilic Thermomyces lanuginosus GH11 xylanase, TLX, a disulfide bridge Q1C-Q24C was introduced into the N-terminal region of the enzyme. The apparent temperature optimum shifted upwards at pH 6.5 by about 10°C to 75°C. The resistance to thermal inactivation also increased by about 10°C. The melting temperature measured by CD spectroscopy increased from 66 to 74°C. Therefore the N-terminal disulfide bridge increased both kinetic and thermodynamic stability almost equally. At pH 8 and 70°C, the disulfide bridge increased the enzyme half-life 20-fold in the presence of substrate. In contrast to the situation in acidic-neutral pH, the substrate decreased the thermostability of xylanases in alkaline pH. The upper limit for the performance of the disulfide bridge mutant at pH 9 was 75°C. This study showed that N-terminal disulfide bridges can stabilize even thermostable family GH11 xylanases.
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Affiliation(s)
- Yawei Wang
- Engineering Research Centre of Bioresources in Southern China, College of Life Science, South-central University for Nationalities, Wuhan 430074, China
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Song L, Siguier B, Dumon C, Bozonnet S, O'Donohue MJ. Engineering better biomass-degrading ability into a GH11 xylanase using a directed evolution strategy. BIOTECHNOLOGY FOR BIOFUELS 2012; 5:3. [PMID: 22244361 PMCID: PMC3299623 DOI: 10.1186/1754-6834-5-3] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2011] [Accepted: 01/13/2012] [Indexed: 05/23/2023]
Abstract
BACKGROUND Improving the hydrolytic performance of hemicellulases on lignocellulosic biomass is of considerable importance for second-generation biorefining. To address this problem, and also to gain greater understanding of structure-function relationships, especially related to xylanase action on complex biomass, we have implemented a combinatorial strategy to engineer the GH11 xylanase from Thermobacillus xylanilyticus (Tx-Xyn). RESULTS Following in vitro enzyme evolution and screening on wheat straw, nine best-performing clones were identified, which display mutations at positions 3, 6, 27 and 111. All of these mutants showed increased hydrolytic activity on wheat straw, and solubilized arabinoxylans that were not modified by the parental enzyme. The most active mutants, S27T and Y111T, increased the solubilization of arabinoxylans from depleted wheat straw 2.3-fold and 2.1-fold, respectively, in comparison to the wild-type enzyme. In addition, five mutants, S27T, Y111H, Y111S, Y111T and S27T-Y111H increased total hemicellulose conversion of intact wheat straw from 16.7%tot. xyl (wild-type Tx-Xyn) to 18.6% to 20.4%tot. xyl. Also, all five mutant enzymes exhibited a better ability to act in synergy with a cellulase cocktail (Accellerase 1500), thus procuring increases in overall wheat straw hydrolysis. CONCLUSIONS Analysis of the results allows us to hypothesize that the increased hydrolytic ability of the mutants is linked to (i) improved ligand binding in a putative secondary binding site, (ii) the diminution of surface hydrophobicity, and/or (iii) the modification of thumb flexibility, induced by mutations at position 111. Nevertheless, the relatively modest improvements that were observed also underline the fact that enzyme engineering alone cannot overcome the limits imposed by the complex organization of the plant cell wall and the lignin barrier.
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Affiliation(s)
- Letian Song
- Université de Toulouse; INSA, UPS, INP; LISBP, 135 Avenue de Rangueil, F-31077 Toulouse, France
- INRA, UMR792, F-31400 Toulouse, France
- CNRS, UMR5504, F-31400 Toulouse, France
| | - Béatrice Siguier
- Université de Toulouse; INSA, UPS, INP; LISBP, 135 Avenue de Rangueil, F-31077 Toulouse, France
- INRA, UMR792, F-31400 Toulouse, France
- CNRS, UMR5504, F-31400 Toulouse, France
- CNRS, Institut de Pharmacologie et de Biologie Structurale, F-31077 Toulouse, France
| | - Claire Dumon
- Université de Toulouse; INSA, UPS, INP; LISBP, 135 Avenue de Rangueil, F-31077 Toulouse, France
- INRA, UMR792, F-31400 Toulouse, France
- CNRS, UMR5504, F-31400 Toulouse, France
| | - Sophie Bozonnet
- Université de Toulouse; INSA, UPS, INP; LISBP, 135 Avenue de Rangueil, F-31077 Toulouse, France
- INRA, UMR792, F-31400 Toulouse, France
- CNRS, UMR5504, F-31400 Toulouse, France
| | - Michael J O'Donohue
- Université de Toulouse; INSA, UPS, INP; LISBP, 135 Avenue de Rangueil, F-31077 Toulouse, France
- INRA, UMR792, F-31400 Toulouse, France
- CNRS, UMR5504, F-31400 Toulouse, France
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Paës G, Chabbert B. Characterization of Arabinoxylan/Cellulose Nanocrystals Gels to Investigate Fluorescent Probes Mobility in Bioinspired Models of Plant Secondary Cell Wall. Biomacromolecules 2011; 13:206-14. [DOI: 10.1021/bm201475a] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Gabriel Paës
- INRA, UMR614 Fractionnement des AgroRessources et Environnement, Reims, France
- University of Reims Champagne-Ardenne, UMR614 Fractionnement des AgroRessources
et Environnement, Reims, France
| | - Brigitte Chabbert
- INRA, UMR614 Fractionnement des AgroRessources et Environnement, Reims, France
- University of Reims Champagne-Ardenne, UMR614 Fractionnement des AgroRessources
et Environnement, Reims, France
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Gladden JM, Eichorst SA, Hazen TC, Simmons BA, Singer SW. Substrate perturbation alters the glycoside hydrolase activities and community composition of switchgrass-adapted bacterial consortia. Biotechnol Bioeng 2011; 109:1140-5. [PMID: 22125273 DOI: 10.1002/bit.24388] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2011] [Revised: 11/11/2011] [Accepted: 11/17/2011] [Indexed: 11/11/2022]
Abstract
Bacteria modulate glycoside hydrolase expression in response to the changes in the composition of lignocellulosic biomass. The response of switchgrass-adapted thermophilic bacterial consortia to perturbation with a variety of biomass substrates was characterized to determine if bacterial consortia also responded to changes in biomass composition. Incubation of the switchgrass-adapted consortia with these alternative substrates produced shifts in glycoside hydrolase activities and bacterial community composition. Substantially increased endoglucanase activity was observed upon incubation with microcrystalline cellulose and trifluororacetic acid-pretreated switchgrass. In contrast, culturing the microbial consortia with ionic liquid-pretreated switchgrass increased xylanase activity dramatically. Microbial community analyses of these cultures indicated that the increased endoglucanase activity correlated with an increase in bacteria related to Rhodothermus marinus. Inclusion of simple organic substrates in the culture medium abrogated glycoside hydrolase activity and enriched for bacteria related to Thermus thermophilus. These results demonstrate that the composition of biomass substrates influences the glycoside hydrolase activities and community composition of biomass-deconstructing bacterial consortia.
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Affiliation(s)
- John M Gladden
- Joint BioEnergy Institute, Emeryville, California 94608, USA
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Paës G, Berrin JG, Beaugrand J. GH11 xylanases: Structure/function/properties relationships and applications. Biotechnol Adv 2011; 30:564-92. [PMID: 22067746 DOI: 10.1016/j.biotechadv.2011.10.003] [Citation(s) in RCA: 287] [Impact Index Per Article: 22.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2011] [Revised: 10/06/2011] [Accepted: 10/13/2011] [Indexed: 01/02/2023]
Abstract
For technical, environmental and economical reasons, industrial demands for process-fitted enzymes have evolved drastically in the last decade. Therefore, continuous efforts are made in order to get insights into enzyme structure/function relationships to create improved biocatalysts. Xylanases are hemicellulolytic enzymes, which are responsible for the degradation of the heteroxylans constituting the lignocellulosic plant cell wall. Due to their variety, xylanases have been classified in glycoside hydrolase families GH5, GH8, GH10, GH11, GH30 and GH43 in the CAZy database. In this review, we focus on GH11 family, which is one of the best characterized GH families with bacterial and fungal members considered as true xylanases compared to the other families because of their high substrate specificity. Based on an exhaustive analysis of the sequences and 3D structures available so far, in relation with biochemical properties, we assess biochemical aspects of GH11 xylanases: structure, catalytic machinery, focus on their "thumb" loop of major importance in catalytic efficiency and substrate selectivity, inhibition, stability to pH and temperature. GH11 xylanases have for a long time been used as biotechnological tools in various industrial applications and represent in addition promising candidates for future other uses.
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Affiliation(s)
- Gabriel Paës
- INRA, UMR614 FARE, 2 esplanade Roland-Garros, F-51686 Reims, France.
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Yeoman CJ, Han Y, Dodd D, Schroeder CM, Mackie RI, Cann IKO. Thermostable enzymes as biocatalysts in the biofuel industry. ADVANCES IN APPLIED MICROBIOLOGY 2010; 70:1-55. [PMID: 20359453 DOI: 10.1016/s0065-2164(10)70001-0] [Citation(s) in RCA: 173] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Lignocellulose is the most abundant carbohydrate source in nature and represents an ideal renewable energy source. Thermostable enzymes that hydrolyze lignocellulose to its component sugars have significant advantages for improving the conversion rate of biomass over their mesophilic counterparts. We review here the recent literature on the development and use of thermostable enzymes for the depolymerization of lignocellulosic feedstocks for biofuel production. Furthermore, we discuss the protein structure, mechanisms of thermostability, and specific strategies that can be used to improve the thermal stability of lignocellulosic biocatalysts.
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Affiliation(s)
- Carl J Yeoman
- Institute for Genomic Biology, University of Illinois, Urbana, Illinois, USA
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