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St John FJ, Bynum L, Tauscheck DA, Crooks C. Use of xylosidase 3C from Segatella baroniae to discriminate xylan non-reducing terminus substitution characteristics. BMC Res Notes 2024; 17:175. [PMID: 38915023 PMCID: PMC11197168 DOI: 10.1186/s13104-024-06835-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Accepted: 06/17/2024] [Indexed: 06/26/2024] Open
Abstract
OBJECTIVE New characterized carbohydrate-active enzymes are needed for use as tools to discriminate complex carbohydrate structural features. Fungal glycoside hydrolase family 3 (GH3) β-xylosidases have been shown to be useful for the structural elucidation of glucuronic acid (GlcA) and arabinofuranose (Araf) substituted oligoxylosides. A homolog of these GH3 fungal enzymes from the bacterium Segatella baroniae (basonym Prevotella bryantii), Xyl3C, has been previously characterized, but those studies did not address important functional specificity features. In an interest to utilize this enzyme for laboratory methods intended to discriminate the structure of the non-reducing terminus of substituted xylooligosaccharides, we have further characterized this GH3 xylosidase. RESULTS In addition to verification of basic functional characteristics of this xylosidase we have determined its mode of action as it relates to non-reducing end xylose release from GlcA and Araf substituted oligoxylosides. Xyl3C cleaves xylose from the non-reducing terminus of β-1,4-xylan until occurrence of a penultimate substituted xylose. If this substitution is O2 linked, then Xyl3C removes the non-reducing xylose to leave the substituted xylose as the new non-reducing terminus. However, if the substitution is O3 linked, Xyl3C does not hydrolyze, thus leaving the substitution one-xylose (penultimate) from the non-reducing terminus. Hence, Xyl3C enables discrimination between O2 and O3 linked substitutions on the xylose penultimate to the non-reducing end. These findings are contrasted using a homologous enzyme also from S. baroniae, Xyl3B, which is found to yield a penultimate substituted nonreducing terminus regardless of which GlcA or Araf substitution exists.
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Affiliation(s)
- Franz J St John
- Institute for Microbial and Biochemical Technology, Forest Products Laboratory, USDA Forest Service, One Gifford Pinchot Dr, Madison, WI, 53726, USA.
| | - Loreen Bynum
- Institute for Microbial and Biochemical Technology, Forest Products Laboratory, USDA Forest Service, One Gifford Pinchot Dr, Madison, WI, 53726, USA
| | - Dante A Tauscheck
- Institute for Microbial and Biochemical Technology, Forest Products Laboratory, USDA Forest Service, One Gifford Pinchot Dr, Madison, WI, 53726, USA
| | - Casey Crooks
- Institute for Microbial and Biochemical Technology, Forest Products Laboratory, USDA Forest Service, One Gifford Pinchot Dr, Madison, WI, 53726, USA
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Mendonça M, Barroca M, Collins T. Endo-1,4-β-xylanase-containing glycoside hydrolase families: Characteristics, singularities and similarities. Biotechnol Adv 2023; 65:108148. [PMID: 37030552 DOI: 10.1016/j.biotechadv.2023.108148] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 04/02/2023] [Accepted: 04/04/2023] [Indexed: 04/09/2023]
Abstract
Endo-1,4-β-xylanases (EC 3.2.1.8) are O-glycoside hydrolases that cleave the internal β-1,4-D-xylosidic linkages of the complex plant polysaccharide xylan. They are produced by a vast array of organisms where they play critical roles in xylan saccharification and plant cell wall hydrolysis. They are also important industrial biocatalysts with widespread application. A large and ever growing number of xylanases with wildly different properties and functionalites are known and a better understanding of these would enable a more effective use in various applications. The Carbohydrate-Active enZYmes database (CAZy), which classifies evolutionarily related proteins into a glycoside hydrolase family-subfamily organisational scheme has proven powerful in understanding these enzymes. Nevertheless, ambiguity currently exists as to the number of glycoside hydrolase families and subfamilies harbouring catalytic domains with true endoxylanase activity and as to the specific characteristics of each of these families/subfamilies. This review seeks to clarify this, identifying 9 glycoside hydrolase families containing enzymes with endo-1,4-β-xylanase activity and discussing their properties, similarities, differences and biotechnological perspectives. In particular, substrate specificities and hydrolysis patterns and the structural determinants of these are detailed, with taxonomic aspects of source organisms being also presented. Shortcomings in current knowledge and research areas that require further clarification are highlighted and suggestions for future directions provided. This review seeks to motivate further research on these enzymes and especially of the lesser known endo-1,4-β-xylanase containing families. A better understanding of these enzymes will serve as a foundation for the knowledge-based development of process-fitted endo-1,4-β-xylanases and will accelerate their development for use with even the most recalcitrant of substrates in the biobased industries of the future.
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Li X, Dilokpimol A, Kabel MA, de Vries RP. Fungal xylanolytic enzymes: Diversity and applications. BIORESOURCE TECHNOLOGY 2022; 344:126290. [PMID: 34748977 DOI: 10.1016/j.biortech.2021.126290] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Revised: 10/29/2021] [Accepted: 11/01/2021] [Indexed: 05/26/2023]
Abstract
As important polysaccharide degraders in nature, fungi can diversify their extensive set of carbohydrate-active enzymes to survive in ecological habitats of various composition. Among these enzymes, xylanolytic ones can efficiently and sustainably degrade xylans into (fermentable) monosaccharides to produce valuable chemicals or fuels from, for example relevant for upgrading agro-food industrial side streams. Moreover, xylanolytic enzymes are being used in various industrial applications beyond biomass saccharification, e.g. food, animal feed, biofuel, pulp and paper. As a reference for researchers working in related areas, this review summarized the current knowledge on substrate specificity of xylanolytic enzymes from different families of the Carbohydrate-Active enZyme database. Additionally, the diversity of enzyme sets in fungi were discussed by comparing the number of genes encoding xylanolytic enzymes in selected fungal genomes. Finally, to support bio-economy, the current applications of fungal xylanolytic enzymes in industry were reviewed.
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Affiliation(s)
- Xinxin Li
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands
| | - Adiphol Dilokpimol
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands
| | - Mirjam A Kabel
- Laboratory of Food Chemistry, Wageningen University & Research, Bornse Weilanden 9, 6708 WG Wageningen, The Netherlands
| | - Ronald P de Vries
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands.
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Koh S, Mizuno M, Izuoka Y, Fujino N, Hamada-Sato N, Amano Y. Xylanase from Marine Filamentous Fungus Pestalotiopsis sp. AN-7 Was Activated with Diluted Salt Solution Like Brackish Water. J Appl Glycosci (1999) 2021; 68:11-18. [PMID: 34354541 PMCID: PMC8116177 DOI: 10.5458/jag.jag.jag-2020_0011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Accepted: 11/16/2020] [Indexed: 11/14/2022] Open
Abstract
The genus Pestalotiopsis are endophytic fungi that have recently been identified as cellulolytic system producers. We herein cloned a gene coding for a xylanase belonging to glycoside hydrolase (GH) family 10 (PesXyn10A) from Pestalotiopsis sp. AN-7, which was isolated from the soil of a mangrove forest. This protein was heterologously expressed by Pichia pastoris as a host, and its enzymatic properties were characterized. PesXyn10A was produced as a glycosylated protein and coincident to theoretical molecular weight (35.3 kDa) after deglycosylation by peptide-NfF-glycosidase F. Purified recombinant PesXyn10A exhibited maximal activity at pH 6.0 and 50 °C, and activity was maintained at 90 % at pH 5.0 and temperatures lower than 30 °C for 24 h. The substrate specificity of PesXyn10A was limited and it hydrolyzed glucuronoxylan and arabinoxylan, but not β-glucan. The final hydrolysis products from birchwood xylan were xylose, xylobiose, and 1,23-α-D-(4-O-methyl-glucuronyl)-1,4-β-D-xylotriose. The addition of metallic salts (NaCl, KCl, MgCl2, and CaCl2) activated PesXyn10A for xylan degradation, and maximal activation by these divalent cations was approximately 160 % at a concentration of 5 mM. The thermostability of PesXyn10A significantly increased in the presence of 50 mM NaCl or 5 mM MgCl2. The present results suggest that the presence of metallic salts at a low concentration, similar to brackish water, exerts positive effects on the enzyme activity and thermal stability of PesXyn10A.
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Affiliation(s)
- Sangho Koh
- 1 Department of Bioscience and Textile Technology, Interdisciplinary Graduate School of Science and Technology. Shinshu University
| | - Masahiro Mizuno
- 1 Department of Bioscience and Textile Technology, Interdisciplinary Graduate School of Science and Technology. Shinshu University.,2 Department of Chemistry and Material Engineering, Faculty of Engineering, Shinshu University
| | - Yuto Izuoka
- 2 Department of Chemistry and Material Engineering, Faculty of Engineering, Shinshu University
| | - Naoto Fujino
- 2 Department of Chemistry and Material Engineering, Faculty of Engineering, Shinshu University.,4 Present address: Biomaterial in Tokyo Co., Ltd
| | - Naoko Hamada-Sato
- 3 Graduate School of Marine Science and Technology, Tokyo University of Marine Science and Technology
| | - Yoshihiko Amano
- 1 Department of Bioscience and Textile Technology, Interdisciplinary Graduate School of Science and Technology. Shinshu University.,2 Department of Chemistry and Material Engineering, Faculty of Engineering, Shinshu University
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Brandt SC, Ellinger B, van Nguyen T, Harder S, Schlüter H, Hahnke RL, Rühl M, Schäfer W, Gand M. Aspergillus sydowii: Genome Analysis and Characterization of Two Heterologous Expressed, Non-redundant Xylanases. Front Microbiol 2020; 11:2154. [PMID: 33071998 PMCID: PMC7531221 DOI: 10.3389/fmicb.2020.573482] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Accepted: 08/14/2020] [Indexed: 12/28/2022] Open
Abstract
A prerequisite for the transition toward a biobased economy is the identification and development of efficient enzymes for the usage of renewable resources as raw material. Therefore, different xylanolytic enzymes are important for efficient enzymatic hydrolysis of xylan-heteropolymers. A powerful tool to overcome the limited enzymatic toolbox lies in exhausting the potential of unexplored habitats. By screening a Vietnamese fungal culture collection of 295 undiscovered fungal isolates, 12 highly active xylan degraders were identified. One of the best xylanase producing strains proved to be an Aspergillus sydowii strain from shrimp shell (Fsh102), showing a specific activity of 0.6 U/mg. Illumina dye sequencing was used to identify our Fsh102 strain and determine differences to the A. sydowii CBS 593.65 reference strain. With activity based in-gel zymography and subsequent mass spectrometric identification, three potential proteins responsible for xylan degradation were identified. Two of these proteins were cloned from the cDNA and, furthermore, expressed heterologously in Escherichia coli and characterized. Both xylanases, were entirely different from each other, including glycoside hydrolases (GH) families, folds, substrate specificity, and inhibition patterns. The specific enzyme activity applying 0.1% birch xylan of both purified enzymes were determined with 181.1 ± 37.8 or 121.5 ± 10.9 U/mg for xylanase I and xylanase II, respectively. Xylanase I belongs to the GH11 family, while xylanase II is member of the GH10 family. Both enzymes showed typical endo-xylanase activity, the main products of xylanase I are xylobiose, xylotriose, and xylohexose, while xylobiose, xylotriose, and xylopentose are formed by xylanase II. Additionally, xylanase II showed remarkable activity toward xylotriose. Xylanase I is stable when stored up to 30°C and pH value of 9, while xylanase II started to lose significant activity stored at pH 9 after exceeding 3 days of storage. Xylanase II displayed about 40% activity when stored at 50°C for 24 h. The enzymes are tolerant toward mesophilic temperatures, while acting in a broad pH range. With site directed mutagenesis, the active site residues in both enzymes were confirmed. The presented activity and stability justify the classification of both xylanases as highly interesting for further development.
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Affiliation(s)
- Sophie C. Brandt
- Department of Molecular Phytopathology, University of Hamburg, Hamburg, Germany
| | - Bernhard Ellinger
- Department ScreeningPort, Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Hamburg, Germany
| | - Thuat van Nguyen
- Department of Molecular Phytopathology, University of Hamburg, Hamburg, Germany
| | - Sönke Harder
- Mass Spectrometric Proteomics Group, Institute of Clinical Chemistry and Laboratory Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Hartmut Schlüter
- Mass Spectrometric Proteomics Group, Institute of Clinical Chemistry and Laboratory Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Richard L. Hahnke
- Department of Microorganisms, Leibniz Institute DSMZ – German Collection of Microorganisms and Cell Cultures, Braunschweig, Germany
| | - Martin Rühl
- Institute of Food Chemistry and Food Biotechnology, Justus Liebig University Giessen, Giessen, Germany
| | - Wilhelm Schäfer
- Department of Molecular Phytopathology, University of Hamburg, Hamburg, Germany
| | - Martin Gand
- Department of Molecular Phytopathology, University of Hamburg, Hamburg, Germany
- Institute of Food Chemistry and Food Biotechnology, Justus Liebig University Giessen, Giessen, Germany
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Enjalbert T, De La Mare M, Roblin P, Badruna L, Vernet T, Dumon C, Montanier CY. Characterisation of the Effect of the Spatial Organisation of Hemicellulases on the Hydrolysis of Plant Biomass Polymer. Int J Mol Sci 2020; 21:ijms21124360. [PMID: 32575393 PMCID: PMC7353053 DOI: 10.3390/ijms21124360] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 06/15/2020] [Accepted: 06/15/2020] [Indexed: 01/21/2023] Open
Abstract
Synergism between enzymes is of crucial importance in cell metabolism. This synergism occurs often through a spatial organisation favouring proximity and substrate channelling. In this context, we developed a strategy for evaluating the impact of the geometry between two enzymes involved in nature in the recycling of the carbon derived from plant cell wall polymers. By using an innovative covalent association process using two protein fragments, Jo and In, we produced two bi-modular chimeric complexes connecting a xylanase and a xylosidase, involved in the deconstruction of xylose-based plant cell wall polymer. We first show that the intrinsic activity of the individual enzymes was preserved. Small Angle X-rays Scattering (SAXS) analysis of the complexes highlighted two different spatial organisations in solution, affecting both the distance between the enzymes (53 Å and 28 Å) and the distance between the catalytic pockets (94 Å and 75 Å). Reducing sugar and HPAEC-PAD analysis revealed different behaviour regarding the hydrolysis of Beechwood xylan. After 24 h of hydrolysis, one complex was able to release a higher amount of reducing sugar compare to the free enzymes (i.e., 15,640 and 14,549 µM of equivalent xylose, respectively). However, more interestingly, the two complexes were able to release variable percentages of xylooligosaccharides compared to the free enzymes. The structure of the complexes revealed some putative steric hindrance, which impacted both enzymatic efficiency and the product profile. This report shows that controlling the spatial geometry between two enzymes would help to better investigate synergism effect within complex multi-enzymatic machinery and control the final product.
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Affiliation(s)
- Thomas Enjalbert
- Toulouse Biotechnology Institute (TBI), Université de Toulouse, CNRS, INRAE, INSA, 31077 Toulouse, France; (T.E.); (L.B.); (C.D.)
| | - Marion De La Mare
- Toulouse White Biotechnology, UMS INRA 1337, UMS CNRS 3582, Institut National des Sciences Appliquées de Toulouse, 31077 Toulouse, France;
| | - Pierre Roblin
- Laboratoire de Génie Chimique, Université de Toulouse, CNRS, INPT, UPS, 31077 Toulouse, France;
| | - Louise Badruna
- Toulouse Biotechnology Institute (TBI), Université de Toulouse, CNRS, INRAE, INSA, 31077 Toulouse, France; (T.E.); (L.B.); (C.D.)
| | - Thierry Vernet
- Institut de Biologie Structurale, Univ., Grenoble Alpes, CEA, CNRS, IBS, F-38000 Grenoble, France;
| | - Claire Dumon
- Toulouse Biotechnology Institute (TBI), Université de Toulouse, CNRS, INRAE, INSA, 31077 Toulouse, France; (T.E.); (L.B.); (C.D.)
| | - Cédric Y. Montanier
- Toulouse Biotechnology Institute (TBI), Université de Toulouse, CNRS, INRAE, INSA, 31077 Toulouse, France; (T.E.); (L.B.); (C.D.)
- Correspondence: ; Tel.: +33-(0)5-61-55-97-13
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Underlin EN, d'Errico C, Böhm M, Madsen R. Synthesis of Glucuronoxylan Hexasaccharides by Preactivation-Based Glycosylations. European J Org Chem 2020. [DOI: 10.1002/ejoc.202000211] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Emilie N. Underlin
- Department of Chemistry; Technical University of Denmark; 2800 Kgs. Lyngby Denmark
| | - Clotilde d'Errico
- Department of Chemistry; Technical University of Denmark; 2800 Kgs. Lyngby Denmark
| | - Maximilian Böhm
- Department of Chemistry; Technical University of Denmark; 2800 Kgs. Lyngby Denmark
| | - Robert Madsen
- Department of Chemistry; Technical University of Denmark; 2800 Kgs. Lyngby Denmark
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Poletto P, Pereira GN, Monteiro CR, Pereira MAF, Bordignon SE, de Oliveira D. Xylooligosaccharides: Transforming the lignocellulosic biomasses into valuable 5-carbon sugar prebiotics. Process Biochem 2020. [DOI: 10.1016/j.procbio.2020.01.005] [Citation(s) in RCA: 67] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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9
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You S, Xie C, Ma R, Huang HQ, Herman RA, Su XY, Ge Y, Cai HY, Yao B, Wang J, Luo HY. Improvement in catalytic activity and thermostability of a GH10 xylanase and its synergistic degradation of biomass with cellulase. BIOTECHNOLOGY FOR BIOFUELS 2019; 12:278. [PMID: 31827606 PMCID: PMC6892236 DOI: 10.1186/s13068-019-1620-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Accepted: 11/25/2019] [Indexed: 05/29/2023]
Abstract
BACKGROUND Xylanase is one of the most extensively used biocatalysts for biomass degradation. However, its low catalytic efficiency and poor thermostability limit its applications. Therefore, improving the properties of xylanases to enable synergistic degradation of lignocellulosic biomass with cellulase is of considerable significance in the field of bioenergy. RESULTS Using fragment replacement, we improved the catalytic performance and thermostability of a GH10 xylanase, XylE. Of the ten hybrid enzymes obtained, seven showed xylanase activity. Substitution of fragments, M3, M6, M9, and their combinations enhanced the catalytic efficiency (by 2.4- to fourfold) as well as the specific activity (by 1.2- to 3.3-fold) of XylE. The hybrids, XylE-M3, XylE-M3/M6, XylE-M3/M9, and XylE-M3/M6/M9, showed enhanced thermostability, as observed by the increase in the T 50 (3-4.7 °C) and T m (1.1-4.7 °C), and extended t 1/2 (by 1.8-2.3 h). In addition, the synergistic effect of the mutant xylanase and cellulase on the degradation of mulberry bark showed that treatment with both XylE-M3/M6 and cellulase exhibited the highest synergistic effect. In this case, the degree of synergy reached 1.3, and the reducing sugar production and dry matter reduction increased by 148% and 185%, respectively, compared to treatment with only cellulase. CONCLUSIONS This study provides a successful strategy to improve the catalytic properties and thermostability of enzymes. We identified several xylanase candidates for applications in bioenergy and biorefinery. Synergistic degradation experiments elucidated a possible mechanism of cellulase inhibition by xylan and xylo-oligomers.
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Affiliation(s)
- Shuai You
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081 China
- School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang, 212018 People’s Republic of China
- Sericultural Research Institute, Chinese Academy of Agricultural Sciences, Zhenjiang, 212018 People’s Republic of China
| | - Chen Xie
- School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang, 212018 People’s Republic of China
- Sericultural Research Institute, Chinese Academy of Agricultural Sciences, Zhenjiang, 212018 People’s Republic of China
| | - Rui Ma
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081 China
| | - Huo-qing Huang
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081 China
| | - Richard Ansah Herman
- School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang, 212018 People’s Republic of China
- Sericultural Research Institute, Chinese Academy of Agricultural Sciences, Zhenjiang, 212018 People’s Republic of China
| | - Xiao-yun Su
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081 China
| | - Yan Ge
- School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang, 212018 People’s Republic of China
- Sericultural Research Institute, Chinese Academy of Agricultural Sciences, Zhenjiang, 212018 People’s Republic of China
| | - Hui-yi Cai
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081 China
| | - Bin Yao
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081 China
| | - Jun Wang
- School of Biotechnology, Jiangsu University of Science and Technology, Zhenjiang, 212018 People’s Republic of China
- Sericultural Research Institute, Chinese Academy of Agricultural Sciences, Zhenjiang, 212018 People’s Republic of China
| | - Hui-ying Luo
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081 China
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Botto E, Gioia L, Menéndez MDP, Rodríguez P. Pseudozyma sp. isolation from Eucalyptus leaves and its hydrolytic activity over xylan. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2019. [DOI: 10.1016/j.bcab.2019.101282] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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11
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Ito T, Sato A, Takahashi I, Ito T, Takano K, Noge K, Okuda M, Hashizume K. Identification of enzymes from genus Trichoderma that can accelerate formation of ferulic acid and ethyl ferulate in collaboration with rice koji enzyme in sake mash. J Biosci Bioeng 2019; 128:177-182. [DOI: 10.1016/j.jbiosc.2019.01.014] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Revised: 12/22/2018] [Accepted: 01/18/2019] [Indexed: 11/28/2022]
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Mode of Action of GH30-7 Reducing-End Xylose-Releasing Exoxylanase A (Xyn30A) from the Filamentous Fungus Talaromyces cellulolyticus. Appl Environ Microbiol 2019; 85:AEM.00552-19. [PMID: 31003983 DOI: 10.1128/aem.00552-19] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Accepted: 04/14/2019] [Indexed: 11/20/2022] Open
Abstract
In this study, we characterized the mode of action of reducing-end xylose-releasing exoxylanase (Rex), which belongs to the glycoside hydrolase family 30-7 (GH30-7). GH30-7 Rex, isolated from the cellulolytic fungus Talaromyces cellulolyticus (Xyn30A), exists as a dimer. The purified Xyn30A released xylose from linear xylooligosaccharides (XOSs) 3 to 6 xylose units in length with similar kinetic constants. Hydrolysis of branched, borohydride-reduced, and p-nitrophenyl XOSs clarified that Xyn30A possesses a Rex activity. 1H nuclear magnetic resonance (1H NMR) analysis of xylotriose hydrolysate indicated that Xyn30A degraded XOSs via a retaining mechanism and without recognizing an anomeric structure at the reducing end. Hydrolysis of xylan by Xyn30A revealed that the enzyme continuously liberated both xylose and two types of acidic XOSs: 22-(4-O-methyl-α-d-glucuronyl)-xylotriose (MeGlcA2Xyl3) and 22-(MeGlcA)-xylobiose (MeGlcA2Xyl2). These acidic products were also detected during hydrolysis using a mixture of MeGlcA2Xyl n (n = 2 to 14) as the substrate. This indicates that Xyn30A can release MeGlcA2Xyl n (n = 2 and 3) in an exo manner. Comparison of subsites in Xyn30A and GH30-7 glucuronoxylanase using homology modeling suggested that the binding of the reducing-end residue at subsite +2 was partially prevented by a Gln residue conserved in GH30-7 Rex; additionally, the Arg residue at subsite -2b, which is conserved in glucuronoxylanase, was not found in Xyn30A. Our results lead us to propose that GH30-7 Rex plays a complementary role in hydrolysis of xylan by fungal cellulolytic systems.IMPORTANCE Endo- and exo-type xylanases depolymerize xylan and play crucial roles in the assimilation of xylan in bacteria and fungi. Exoxylanases release xylose from the reducing or nonreducing ends of xylooligosaccharides; this is generated by the activity of endoxylanases. β-Xylosidase, which hydrolyzes xylose residues on the nonreducing end of a substrate, is well studied. However, the function of reducing-end xylose-releasing exoxylanases (Rex), especially in fungal cellulolytic systems, remains unclear. This study revealed the mode of xylan hydrolysis by Rex from the cellulolytic fungus Talaromyces cellulolyticus (Xyn30A), which belongs to the glycoside hydrolase family 30-7 (GH30-7). A conserved residue related to Rex activity is found in the substrate-binding site of Xyn30A. These findings will enhance our understanding of the function of GH30-7 Rex in the cooperative hydrolysis of xylan by fungal enzymes.
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13
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Changing surface grafting density has an effect on the activity of immobilized xylanase towards natural polysaccharides. Sci Rep 2019; 9:5763. [PMID: 30962508 PMCID: PMC6453946 DOI: 10.1038/s41598-019-42206-w] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Accepted: 03/25/2019] [Indexed: 12/22/2022] Open
Abstract
Enzymes are involved in various types of biological processes. In many cases, they are part of multi-component machineries where enzymes are localized in close proximity to each-other. In such situations, it is still not clear whether inter-enzyme spacing actually plays a role or if the colocalization of complementary activities is sufficient to explain the efficiency of the system. Here, we focus on the effect of spatial proximity when identical enzymes are immobilized onto a surface. By using an innovative grafting procedure based on the use of two engineered protein fragments, Jo and In, we produce model systems in which enzymes are immobilized at surface densities that can be controlled precisely. The enzyme used is a xylanase that participates to the hydrolysis of plant cell wall polymers. By using a small chromogenic substrate, we first show that the intrinsic activity of the enzymes is fully preserved upon immobilization and does not depend on surface density. However, when using beechwood xylan, a naturally occurring polysaccharide, as substrate, we find that the enzymatic efficiency decreases by 10–60% with the density of grafting. This unexpected result is probably explained through steric hindrance effects at the nanoscale that hinder proper interaction between the enzymes and the polymer. A second effect of enzyme immobilization at high densities is the clear tendency for the system to release preferentially shorter oligosaccharides from beechwood xylan as compared to enzymes in solution.
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Ray S, Vigouroux J, Bouder A, Francin Allami M, Geairon A, Fanuel M, Ropartz D, Helbert W, Lahaye M, Bonnin E. Functional exploration of Pseudoalteromonas atlantica as a source of hemicellulose-active enzymes: Evidence for a GH8 xylanase with unusual mode of action. Enzyme Microb Technol 2019; 127:6-16. [PMID: 31088618 DOI: 10.1016/j.enzmictec.2019.04.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Revised: 03/26/2019] [Accepted: 04/07/2019] [Indexed: 11/18/2022]
Abstract
To address the need for efficient enzymes exhibiting novel activities towards cell wall polysaccharides, the bacterium Pseudoalteromonas atlantica was selected based on the presence of potential hemicellulases in its annotated genome. It was grown in the presence or not of hemicelluloses and the culture filtrates were screened towards 42 polysaccharides. P. atlantica showed appreciable diversity of enzymes active towards hemicelluloses from Monocot and Dicot origin, in agreement with its genome annotation. After growth on beechwood glucuronoxylan and fractionation of the secretome, a β-xylosidase, a α-arabinofuranosidase and an acetylesterase activities were evidenced. A GH8 enzyme obtained in the same growth conditions was further cloned and heterologously overexpressed. It was shown to be a xylanase active on heteroxylans from various sources. The detailed study of its mode of action demonstrated that the oligosaccharides produced carried a long tail of un-substituted xylose residues on the reducing end.
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Affiliation(s)
- Sayani Ray
- INRA, UR 1268 Biopolymères - Interactions - Assemblages, 44 316 Nantes, France; Department of Chemistry, The University of Burdwan, Burdwan, 713104 West Bengal, India
| | | | - Axelle Bouder
- INRA, UR 1268 Biopolymères - Interactions - Assemblages, 44 316 Nantes, France
| | | | - Audrey Geairon
- INRA, UR 1268 Biopolymères - Interactions - Assemblages, 44 316 Nantes, France
| | - Mathieu Fanuel
- INRA, UR 1268 Biopolymères - Interactions - Assemblages, 44 316 Nantes, France
| | - David Ropartz
- INRA, UR 1268 Biopolymères - Interactions - Assemblages, 44 316 Nantes, France
| | - William Helbert
- CERMAV-CNRS, 601 rue de la Chimie, BP53, 38041 Grenoble, France
| | - Marc Lahaye
- INRA, UR 1268 Biopolymères - Interactions - Assemblages, 44 316 Nantes, France
| | - Estelle Bonnin
- INRA, UR 1268 Biopolymères - Interactions - Assemblages, 44 316 Nantes, France.
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Fouquet T, Sato H, Nakamichi Y, Matsushika A, Inoue H. Electrospray multistage mass spectrometry in the negative ion mode for the unambiguous molecular and structural characterization of acidic hydrolysates from 4-O-methylglucuronoxylan generated by endoxylanases. JOURNAL OF MASS SPECTROMETRY : JMS 2019; 54:213-221. [PMID: 30597672 DOI: 10.1002/jms.4321] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Revised: 12/14/2018] [Accepted: 12/16/2018] [Indexed: 06/09/2023]
Abstract
A rapid analytical methodology is proposed to answer the two questions about the molecular and structural features of the acidic xylo-oligosaccharides (XOSs) formed upon the enzymatic hydrolysis of 4-O-methylglucuronoxylan. The shortest acidic XOSs carrying a methylglucuronic acid moiety and the possible distribution of larger products (molecular feature) are instantly found by electrospray ionization mass spectrometry (ESI-MS) in the negative ion mode, which filters the unwanted neutral XOS. The acidic moiety is then unambiguously localized along the xylose backbone (structural feature) by ESI-MSn in the negative ion mode via the selection/activation/dissociation of the product ions formed upon the one-way and stepwise glycosidic bond cleavage at the reducing end. Using the shortest acidic XOS with a known shape generated by glycoside hydrolase family (GH) 10 and GH11 xylanases as a proof of principle, pairs of diagnostic ions are proposed to instantly interpret the MSn fingerprints and localize the acidic moiety along the xylose chain of the activated ion. The original structure of the acidic XOS is then reconstructed by adding as many xylose units at the reducing end as MSn steps. Relying on pairs of ions, the methodology is robust enough to highlight the presence of isomeric products. Mass spectra reported in the present article will be conveniently used as reference data for the forthcoming analysis of acidic XOS generated by new classes of enzymes using this multistage mass spectrometry methodology.
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Affiliation(s)
- Thierry Fouquet
- Polymer Chemistry Group, Research Institute for Sustainable Chemistry, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba Ibaraki, Japan
| | - Hiroaki Sato
- Polymer Chemistry Group, Research Institute for Sustainable Chemistry, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba Ibaraki, Japan
| | - Yusuke Nakamichi
- Bioconversion Group, Research Institute for Sustainable Chemistry, National Institute of Advanced Industrial Science and Technology (AIST), Hiroshima, Japan
| | - Akinori Matsushika
- Bioconversion Group, Research Institute for Sustainable Chemistry, National Institute of Advanced Industrial Science and Technology (AIST), Hiroshima, Japan
| | - Hiroyuki Inoue
- Bioconversion Group, Research Institute for Sustainable Chemistry, National Institute of Advanced Industrial Science and Technology (AIST), Hiroshima, Japan
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Arai T, Biely P, Uhliariková I, Sato N, Makishima S, Mizuno M, Nozaki K, Kaneko S, Amano Y. Structural characterization of hemicellulose released from corn cob in continuous flow type hydrothermal reactor. J Biosci Bioeng 2018; 127:222-230. [PMID: 30143337 DOI: 10.1016/j.jbiosc.2018.07.016] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Revised: 06/22/2018] [Accepted: 07/18/2018] [Indexed: 11/18/2022]
Abstract
Hydrothermal reaction is known to be one of the most efficient procedures to extract hemicelluloses from lignocellulosic biomass. We investigated the molecular structure of xylooligosaccharides released from corn cob in a continuous flow type hydrothermal reactor designed in our group. The fraction precipitable from the extract with four volumes of ethanol was examined by 1H-NMR spectroscopy and MALDI-TOF MS before and after enzymatic treatment with different purified enzymes. The released water-soluble hemicellulose was found to correspond to a mixture of wide degree of polymerization range of acetylarabinoglucuronoxylan fragments (further as corn cob xylan abbreviated CX). Analysis of enzymatic hydrolyzates of CX with an acetylxylan esterase, GH3 β-xylosidase, GH10 and GH11 xylanases revealed that the main chain contains unsubstituted regions mixed with regions of xylopyranosyl residues partially acetylated and occasionally substituted by 4-O-methyl-d-glucuronic acid and arabinofuranose esterified with ferulic or coumaric acid. Single 2- and 3-O-acetylation was accompanied by 2,3-di-O-acetylation and 3-O-acetylation of Xylp residues substituted with MeGlcA. Most of the non-esterified arabinofuranose side residues were lost during the hydrodynamic process. Despite reduced branching, the acetylation and ferulic acid modification of pentose residues contribute to high yields and high solubility of the extracted CX. It is also shown that different enzyme treatments of CX may lead to various types of xylooligosaccharides of different biomedical potential.
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Affiliation(s)
- Tsutomu Arai
- Department of Chemistry and Material Engineering, Faculty of Engineering, Shinshu University, 4-17-1 Wakasato, Nagano 380-8553, Japan
| | - Peter Biely
- Institute of Chemistry, Slovak Academy of Sciences, Dúbravská Cesta 9, 845 38 Bratislava, Slovak Republic
| | - Iveta Uhliariková
- Institute of Chemistry, Slovak Academy of Sciences, Dúbravská Cesta 9, 845 38 Bratislava, Slovak Republic
| | - Nobuaki Sato
- Department of Chemistry and Material Engineering, Faculty of Engineering, Shinshu University, 4-17-1 Wakasato, Nagano 380-8553, Japan; B Food Science Co. Ltd., 24-12 Kitahamamachi, Chita 478-0046, Japan
| | - Satoshi Makishima
- Department of Chemistry and Material Engineering, Faculty of Engineering, Shinshu University, 4-17-1 Wakasato, Nagano 380-8553, Japan; B Food Science Co. Ltd., 24-12 Kitahamamachi, Chita 478-0046, Japan
| | - Masahiro Mizuno
- Department of Chemistry and Material Engineering, Faculty of Engineering, Shinshu University, 4-17-1 Wakasato, Nagano 380-8553, Japan; Institute of Engineering, Academic Assembly, Shinshu University, 4-17-1 Wakasato, Nagano 380-8553, Japan
| | - Kouichi Nozaki
- Department of Chemistry and Material Engineering, Faculty of Engineering, Shinshu University, 4-17-1 Wakasato, Nagano 380-8553, Japan; Institute of Engineering, Academic Assembly, Shinshu University, 4-17-1 Wakasato, Nagano 380-8553, Japan
| | - Satoshi Kaneko
- Department of Subtropical Bioscience and Biotechnology, University of the Ryukyus, Nishiara, Okinawa 903-0213, Japan
| | - Yoshihiko Amano
- Department of Chemistry and Material Engineering, Faculty of Engineering, Shinshu University, 4-17-1 Wakasato, Nagano 380-8553, Japan; Institute of Engineering, Academic Assembly, Shinshu University, 4-17-1 Wakasato, Nagano 380-8553, Japan.
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Valls C, Pastor FJ, Vidal T, Roncero MB, Díaz P, Martínez J, Valenzuela SV. Antioxidant activity of xylooligosaccharides produced from glucuronoxylan by Xyn10A and Xyn30D xylanases and eucalyptus autohydrolysates. Carbohydr Polym 2018; 194:43-50. [DOI: 10.1016/j.carbpol.2018.04.028] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 04/04/2018] [Accepted: 04/05/2018] [Indexed: 01/07/2023]
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19
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Long L, Tian D, Zhai R, Li X, Zhang Y, Hu J, Wang F, Saddler J. Thermostable xylanase-aided two-stage hydrolysis approach enhances sugar release of pretreated lignocellulosic biomass. BIORESOURCE TECHNOLOGY 2018; 257:334-338. [PMID: 29500062 DOI: 10.1016/j.biortech.2018.02.104] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Revised: 02/21/2018] [Accepted: 02/22/2018] [Indexed: 05/16/2023]
Abstract
One of the challenges in biorefinery is the still too much enzyme involved in the saccharification of the cellulosic component. High-temperature hydrolysis with thermostable enzyme showed promise. In this study, a temperature-elevated two-stage hydrolysis, including xylan "coat" removal at high-temperature by thermostable xylanase (Xyn10A) from Thermotoga thermarum DSM 5069 followed with saccharification step by commercial cellulase, was introduced to improve biomass deconstruction. Results showed that high-temperature xylanase treatment considerably increased cellulose accessibility/hydrolyzability towards cellulases, with smoothed fiber surface morphology. Comparing with commercial xylanase (HTec) treatment at 50 °C, thermostable Xyn10A pre-hydrolysis at 85 °C was able to achieve a slightly better improvement of cellulose hydrolysis with much lower xylanase loading (about 5 times lower than HTec). It appeared that the increased temperature during thermostable xylanase treatment facilitated biomass slurry viscosity reduction, which exhibited more benefits during hydrolysis of various steam pretreated substrates at increased solid content (up to 10% w/w).
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Affiliation(s)
- Lingfeng Long
- College of Chemical Engineering, Nanjing Forestry University, Jiangsu Key Lab for the Chemistry and Utilization of Agro-forest Biomass, Nanjing 210037, PR China; Department of Wood Science, University of British Columbia, Vancouver V6T 1Z4, Canada
| | - Dong Tian
- Department of Wood Science, University of British Columbia, Vancouver V6T 1Z4, Canada
| | - Rui Zhai
- Department of Wood Science, University of British Columbia, Vancouver V6T 1Z4, Canada
| | - Xun Li
- College of Chemical Engineering, Nanjing Forestry University, Jiangsu Key Lab for the Chemistry and Utilization of Agro-forest Biomass, Nanjing 210037, PR China
| | - Yu Zhang
- College of Chemical Engineering, Nanjing Forestry University, Jiangsu Key Lab for the Chemistry and Utilization of Agro-forest Biomass, Nanjing 210037, PR China
| | - Jinguang Hu
- Department of Wood Science, University of British Columbia, Vancouver V6T 1Z4, Canada.
| | - Fei Wang
- College of Chemical Engineering, Nanjing Forestry University, Jiangsu Key Lab for the Chemistry and Utilization of Agro-forest Biomass, Nanjing 210037, PR China
| | - Jack Saddler
- Department of Wood Science, University of British Columbia, Vancouver V6T 1Z4, Canada
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Zhou T, Xue Y, Ren F, Dong Y. Antioxidant activity of xylooligosaccharides prepared fromThermotoga maritimausing recombinant enzyme cocktail of β-xylanase and α-glucuronidase. J Carbohydr Chem 2018. [DOI: 10.1080/07328303.2018.1455843] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Affiliation(s)
- Tao Zhou
- Department of Food Science and Nutrition, GinLing College, Nanjing Normal University, Nanjing, PR China
| | - Yemin Xue
- Department of Food Science and Nutrition, GinLing College, Nanjing Normal University, Nanjing, PR China
| | - Fengjiao Ren
- Department of Food Science and Nutrition, GinLing College, Nanjing Normal University, Nanjing, PR China
| | - Yuanyuan Dong
- Department of Food Science and Nutrition, GinLing College, Nanjing Normal University, Nanjing, PR China
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A plasmid borne, functionally novel glycoside hydrolase family 30 subfamily 8 endoxylanase from solventogenic Clostridium. Biochem J 2018; 475:1533-1551. [PMID: 29626157 PMCID: PMC5934979 DOI: 10.1042/bcj20180050] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Revised: 03/28/2018] [Accepted: 04/03/2018] [Indexed: 11/24/2022]
Abstract
Glycoside hydrolase family 30 subfamily 8 (GH30-8) β-1,4-endoxylanases are known for their appendage-dependent function requiring recognition of an α-1,2-linked glucuronic acid (GlcA) common to glucuronoxylans for hydrolysis. Structural studies have indicated that the GlcA moiety of glucuronoxylans is coordinated through six hydrogen bonds and a salt bridge. These GlcA-dependent endoxylanases do not have significant activity on xylans that do not bear GlcA substitutions such as unsubstituted linear xylooligosaccharides or cereal bran arabinoxylans. In the present study, we present the structural and biochemical characteristics of xylanase 30A from Clostridium acetobutylicum (CaXyn30A) which was originally selected for study due to predicted structural differences within the GlcA coordination loops. Amino acid sequence comparisons indicated that this Gram-positive-derived GH30-8 more closely resembles Gram-negative derived forms of these endoxylanases: a hypothesis borne out in the developed crystallographic structure model of the CaXyn30A catalytic domain (CaXyn30A-CD). CaXyn30A-CD hydrolyzes xylans to linear and substituted oligoxylosides showing the greatest rate with the highly arabinofuranose (Araf)-substituted cereal arabinoxylans. CaXyn30A-CD hydrolyzes xylooligosaccharides larger than xylotriose and shows an increased relative rate of hydrolysis for xylooligosaccharides containing α-1,2-linked arabinofuranose substitutions. Biochemical analysis confirms that CaXyn30A benefits from five xylose-binding subsites which extend from the −3 subsite to the +2 subsite of the binding cleft. These studies indicate that CaXyn30A is a GlcA-independent endoxylanase that may have evolved for the preferential recognition of α-1,2-Araf substitutions on xylan chains.
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Xiong K, Xiong S, Gao S, Li Q, Sun B, Li X. Improving Hydrolysis Characteristics of Xylanases by Site-Directed Mutagenesis in Binding-Site Subsites from Streptomyces L10608. Int J Mol Sci 2018. [PMID: 29533991 PMCID: PMC5877695 DOI: 10.3390/ijms19030834] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The preparation of oligosaccharides via xylan hydrolysis is an effective way to add value to hemicellulosic material of agricultural waste. The bacterial strain Streptomyces L10608, isolated from soil, contains genes encoding xylanases of glucoside hydrolase family 10/11 (GH10/11), and these have been cloned to catalyze the production of xylooligosaccharide (XOS). To improve the XOS proportion of hydrolysates produced by xylanase, four amino acid residues were substituted by site-directed mutagenesis, and the mutant genes were overexpressed in Escherichia coli. Mutations replaced the codons encoding Asn214 (+2) and Asn86 (−2) by Ala and removed the Ricin B-lectin domain in GH10-xyn, and mutants Y115A (−2) and Y123A (−2) were produced for GH11-xyn. Interestingly, GH10-N86Q had significantly increased hydrolysis of XOS and almost eliminated xylose (X1) to <2.5%, indicating that the −2 binding site of GH10-xyn of L10608 is required for binding with xylotriose (X3). The hydrolytic activity of GH10-N86Q was increased approximately 1.25-fold using beechwood xylan as a substrate and had high affinity for the substrate with a low Km of about 1.85 mg·mL−1. Otherwise, there were no significant differences in enzymatic properties between GH10-N86Q and GH10-xyn. These mutants offer great potential for modification of xylanase with desired XOS hydrolysis.
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Affiliation(s)
- Ke Xiong
- Beijing Innovation Centre of Food Nutrition and Human, Beijing Technology & Business University (BTBU), No. 33 Fucheng Road, Haidian, Beijing 100048, China.
- Beijing Laboratory for Food Quality and Safety, Beijing Technology & Business University (BTBU), No. 33 Fucheng Road, Haidian, Beijing 100048, China.
| | - Suyue Xiong
- Beijing Innovation Centre of Food Nutrition and Human, Beijing Technology & Business University (BTBU), No. 33 Fucheng Road, Haidian, Beijing 100048, China.
- Beijing Engineering and Technology Research Center of Food Additives, Beijing Technology & Business University (BTBU), No. 33 Fucheng Road, Haidian, Beijing 100048, China.
| | - Siyu Gao
- Beijing Innovation Centre of Food Nutrition and Human, Beijing Technology & Business University (BTBU), No. 33 Fucheng Road, Haidian, Beijing 100048, China.
- Beijing Key Laboratory of Flavor Chemistry, Beijing Technology and Business University (BTBU), No. 33 Fucheng Road, Haidian, Beijing 100048, China.
| | - Qin Li
- Beijing Innovation Centre of Food Nutrition and Human, Beijing Technology & Business University (BTBU), No. 33 Fucheng Road, Haidian, Beijing 100048, China.
- Beijing Engineering and Technology Research Center of Food Additives, Beijing Technology & Business University (BTBU), No. 33 Fucheng Road, Haidian, Beijing 100048, China.
| | - Baoguo Sun
- Beijing Innovation Centre of Food Nutrition and Human, Beijing Technology & Business University (BTBU), No. 33 Fucheng Road, Haidian, Beijing 100048, China.
- Beijing Laboratory for Food Quality and Safety, Beijing Technology & Business University (BTBU), No. 33 Fucheng Road, Haidian, Beijing 100048, China.
| | - Xiuting Li
- Beijing Innovation Centre of Food Nutrition and Human, Beijing Technology & Business University (BTBU), No. 33 Fucheng Road, Haidian, Beijing 100048, China.
- Beijing Laboratory for Food Quality and Safety, Beijing Technology & Business University (BTBU), No. 33 Fucheng Road, Haidian, Beijing 100048, China.
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You S, Chen CC, Tu T, Wang X, Ma R, Cai HY, Guo RT, Luo HY, Yao B. Insight into the functional roles of Glu175 in the hyperthermostable xylanase XYL10C-ΔN through structural analysis and site-saturation mutagenesis. BIOTECHNOLOGY FOR BIOFUELS 2018; 11:159. [PMID: 29930705 PMCID: PMC5992652 DOI: 10.1186/s13068-018-1150-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Accepted: 05/23/2018] [Indexed: 05/16/2023]
Abstract
BACKGROUND Improving the hydrolytic performance of hemicellulases to degrade lignocellulosic biomass is of considerable importance for second-generation biorefinery. Xylanase, as the crucial hemicellulase, must be thermostable and have high activity for its potential use in the bioethanol industry. To obtain excellent xylanase candidates, it is necessary to understand the structure-function relationships to provide a meaningful reference to improve the enzyme properties. This study aimed to investigate the catalytic mechanism of a highly active hyperthermophilic xylanase variant, XYL10C-ΔN, for hemicellulose degradation. RESULTS By removing the N-terminal 66 amino acids, the variant XYL10C-ΔN showed a 1.8-fold improvement in catalytic efficiency and could hydrolyze corn stover more efficiently in hydrolysis of corn stover; however, it retained similar thermostability to the wild-type XYL10C. Based on the crystal structures of XYL10C-ΔN and its complex with xylobiose, Glu175 located on loop 3 was found to be specific to GH10 xylanases and probably accounts for the excellent enzyme properties by interacting with Lys135 and Met137 on loop 2. Site-saturation mutagenesis confirmed that XYL10C-ΔN with glutamate acid at position 175 had the highest catalytic efficiency, specific activity, and the broadest pH-activity profile. The functional roles of Glu175 were also verified in the mutants of another two GH10 xylanases, XylE and XynE2, which showed increased catalytic efficiencies and wider pH-activity profiles. CONCLUSIONS XYL10C-ΔN, with excellent thermostability, high catalytic efficiency, and great lignocellulose-degrading capability, is a valuable candidate xylanase for the biofuel industry. The mechanism underlying improved activity of XYN10C-ΔN was thus investigated through structural analysis and functional verification, and Glu175 was identified to play the key role in the improved catalytic efficiency. This study revealed the importance of a key residue (Glu175) in XYN10C-ΔN and provides a reference to modify GH10 xylanases for improved catalytic performance.
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Affiliation(s)
- Shuai You
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081 China
| | - Chun-Chi Chen
- National Engineering Laboratory of Industrial Enzymes, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308 China
- College of Life Sciences, Hubei University, Wuhan, 430062 China
| | - Tao Tu
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081 China
| | - Xiaoyu Wang
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081 China
| | - Rui Ma
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081 China
| | - Hui-yi Cai
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081 China
| | - Rey-Ting Guo
- National Engineering Laboratory of Industrial Enzymes, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin, 300308 China
- College of Life Sciences, Hubei University, Wuhan, 430062 China
| | - Hui-ying Luo
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081 China
| | - Bin Yao
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081 China
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Hassan AS, Houston K, Lahnstein J, Shirley N, Schwerdt JG, Gidley MJ, Waugh R, Little A, Burton RA. A Genome Wide Association Study of arabinoxylan content in 2-row spring barley grain. PLoS One 2017; 12:e0182537. [PMID: 28771585 PMCID: PMC5542645 DOI: 10.1371/journal.pone.0182537] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Accepted: 07/19/2017] [Indexed: 11/18/2022] Open
Abstract
In barley endosperm arabinoxylan (AX) is the second most abundant cell wall polysaccharide and in wheat it is the most abundant polysaccharide in the starchy endosperm walls of the grain. AX is one of the main contributors to grain dietary fibre content providing several health benefits including cholesterol and glucose lowering effects, and antioxidant activities. Due to its complex structural features, AX might also affect the downstream applications of barley grain in malting and brewing. Using a high pressure liquid chromatography (HPLC) method we quantified AX amounts in mature grain in 128 spring 2-row barley accessions. Amounts ranged from ~ 5.2 μg/g to ~ 9 μg/g. We used this data for a Genome Wide Association Study (GWAS) that revealed three significant quantitative trait loci (QTL) associated with grain AX levels which passed a false discovery threshold (FDR) and are located on two of the seven barley chromosomes. Regions underlying the QTLs were scanned for genes likely to be involved in AX biosynthesis or turnover, and strong candidates, including glycosyltransferases from the GT43 and GT61 families and glycoside hydrolases from the GH10 family, were identified. Phylogenetic trees of selected gene families were built based on protein translations and were used to examine the relationship of the barley candidate genes to those in other species. Our data reaffirms the roles of existing genes thought to contribute to AX content, and identifies novel QTL (and candidate genes associated with them) potentially influencing the AX content of barley grain. One potential outcome of this work is the deployment of highly associated single nucleotide polymorphisms markers in breeding programs to guide the modification of AX abundance in barley grain.
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Affiliation(s)
- Ali Saleh Hassan
- ARC Centre of Excellence in Plant Cell Walls, School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, Glen Osmond, South Australia, Australia
| | - Kelly Houston
- The James Hutton Institute, Invergowrie, Dundee, Scotland
| | - Jelle Lahnstein
- ARC Centre of Excellence in Plant Cell Walls, School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, Glen Osmond, South Australia, Australia
| | - Neil Shirley
- ARC Centre of Excellence in Plant Cell Walls, School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, Glen Osmond, South Australia, Australia
| | - Julian G. Schwerdt
- ARC Centre of Excellence in Plant Cell Walls, School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, Glen Osmond, South Australia, Australia
| | - Michael J. Gidley
- ARC Centre of Excellence in Plant Cell Walls, Centre for Nutrition and Food Sciences, Queensland Alliance for Agriculture and Food Innovation, University of Queensland, St Lucia, Queensland, Australia
| | - Robbie Waugh
- Division of Plant Sciences, School of Life Sciences, University of Dundee, Invergowrie, Dundee, Scotland
| | - Alan Little
- ARC Centre of Excellence in Plant Cell Walls, School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, Glen Osmond, South Australia, Australia
| | - Rachel A. Burton
- ARC Centre of Excellence in Plant Cell Walls, School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, Glen Osmond, South Australia, Australia
- * E-mail:
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Morgan NK, Wallace A, Bedford MR, Choct M. Efficiency of xylanases from families 10 and 11 in production of xylo -oligosaccharides from wheat arabinoxylans. Carbohydr Polym 2017; 167:290-296. [DOI: 10.1016/j.carbpol.2017.03.063] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Revised: 02/23/2017] [Accepted: 03/18/2017] [Indexed: 10/19/2022]
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26
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Mechelke M, Koeck DE, Broeker J, Roessler B, Krabichler F, Schwarz WH, Zverlov VV, Liebl W. Characterization of the arabinoxylan-degrading machinery of the thermophilic bacterium Herbinix hemicellulosilytica-Six new xylanases, three arabinofuranosidases and one xylosidase. J Biotechnol 2017; 257:122-130. [PMID: 28450260 DOI: 10.1016/j.jbiotec.2017.04.023] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Revised: 04/20/2017] [Accepted: 04/20/2017] [Indexed: 10/19/2022]
Abstract
Herbinix hemicellulosilytica is a newly isolated, gram-positive, anaerobic bacterium with extensive hemicellulose-degrading capabilities obtained from a thermophilic biogas reactor. In order to exploit its potential as a source for new industrial arabinoxylan-degrading enzymes, six new thermophilic xylanases, four from glycoside hydrolase family 10 (GH10) and two from GH11, three arabinofuranosidases (1x GH43, 2x GH51) and one β-xylosidase (GH43) were selected. The recombinantly produced enzymes were purified and characterized. All enzymes were active on different xylan-based polysaccharides and most of them showed temperature-vs-activity profiles with maxima around 55-65°C. HPAEC-PAD analysis of the hydrolysates of wheat arabinoxylan and of various purified xylooligosaccharides (XOS) and arabinoxylooligosaccharides (AXOS) was used to investigate their substrate and product specificities: among the GH10 xylanases, XynB showed a different product pattern when hydrolysing AXOS compared to XynA, XynC, and XynD. None of the GH11 xylanases was able to degrade any of the tested AXOS. All three arabinofuranosidases, ArfA, ArfB and ArfC, were classified as type AXH-m,d enzymes. None of the arabinofuranosidases was able to degrade the double-arabinosylated xylooligosaccharides XA2+3XX. β-Xylosidase XylA (GH43) was able to degrade unsubstituted XOS, but showed limited activity to degrade AXOS.
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Affiliation(s)
- M Mechelke
- Department of Microbiology, Technical University of Munich, Emil-Ramann-Str. 4, 85354 Freising-Weihenstephan, Germany
| | - D E Koeck
- Department of Microbiology, Technical University of Munich, Emil-Ramann-Str. 4, 85354 Freising-Weihenstephan, Germany
| | - J Broeker
- Department of Microbiology, Technical University of Munich, Emil-Ramann-Str. 4, 85354 Freising-Weihenstephan, Germany
| | - B Roessler
- Department of Microbiology, Technical University of Munich, Emil-Ramann-Str. 4, 85354 Freising-Weihenstephan, Germany
| | - F Krabichler
- Department of Microbiology, Technical University of Munich, Emil-Ramann-Str. 4, 85354 Freising-Weihenstephan, Germany
| | - W H Schwarz
- Department of Microbiology, Technical University of Munich, Emil-Ramann-Str. 4, 85354 Freising-Weihenstephan, Germany
| | - V V Zverlov
- Department of Microbiology, Technical University of Munich, Emil-Ramann-Str. 4, 85354 Freising-Weihenstephan, Germany; Institute of Molecular Genetics, Russian Academy of Science, Kurchatov Sq. 2, 123182 Moscow Russia
| | - W Liebl
- Department of Microbiology, Technical University of Munich, Emil-Ramann-Str. 4, 85354 Freising-Weihenstephan, Germany.
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Flores C, Williams M, Smith K, Pieniazek J, Latham R, Wang J, Tyus J, Lee J. Evaluation of a thermotolerant xylanase on broiler growth performance and dietary ileal digestible energy value. J APPL POULTRY RES 2017. [DOI: 10.3382/japr/pfw046] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Recombinant Thermostable Thermomonospora fusca TF Endo-xylanase A and Its Immobilization on Modified Mesoporous SiO2 Microspheres for Manufacturing Xylooligosaccharides. Catal Letters 2017. [DOI: 10.1007/s10562-017-1979-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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Hachem K, Faugeron C, Kaid-Harche M, Gloaguen V. Structural Investigation of Cell Wall Xylan Polysaccharides from the Leaves of Algerian Argania spinosa. Molecules 2016; 21:molecules21111587. [PMID: 27879638 PMCID: PMC6274131 DOI: 10.3390/molecules21111587] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2016] [Revised: 11/16/2016] [Accepted: 11/16/2016] [Indexed: 11/16/2022] Open
Abstract
Xylan-type polysaccharides were isolated from the leaves of Argania spinosa (L.) Skeels collected in the Tindouf area (southwestern Algeria). Xylan fractions were obtained by sequential alkaline extractions and purified on Sepharose CL-4B. The xylan structure was investigated by enzymatic hydrolysis with an endo-β(1→4)-xylanase followed by chromatography of the resulting fragments on Biogel P2, characterization by sugar analysis and matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS ). The results show that the A. spinosa xylan is composed of a β-(1→4)-d-xylopyranose backbone substituted with 4-O-methyl-d-glucuronic acid and L-arabinose residues.
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Affiliation(s)
- Kadda Hachem
- Laboratoire de Biotoxicologie, Pharmacognosie et Valorisation Biologique des Plantes (LBPVBP), Département de biologie, Faculté des sciences, Université Dr. Tahar Moulay de Saida, BP 138 cité ENNASR, 20000 Saida, Algérie.
- Laboratoire des Productions, Valorisations Végétales et Microbiennes (LP2VM), Département de Biotechnologie, Faculté des sciences de la nature et de la vie, Université des Sciences et de la Technologie d'Oran, BP 1505 El M'Naouar, 31000 Oran, Algérie.
| | - Céline Faugeron
- Laboratoire de Chimie des Substances Naturelles (EA1069), Faculté des Sciences et Techniques, Université de Limoges, 123 avenue Albert Thomas, 87060 Limoges, France.
| | - Meriem Kaid-Harche
- Laboratoire des Productions, Valorisations Végétales et Microbiennes (LP2VM), Département de Biotechnologie, Faculté des sciences de la nature et de la vie, Université des Sciences et de la Technologie d'Oran, BP 1505 El M'Naouar, 31000 Oran, Algérie.
| | - Vincent Gloaguen
- Laboratoire de Chimie des Substances Naturelles (EA1069), Faculté des Sciences et Techniques, Université de Limoges, 123 avenue Albert Thomas, 87060 Limoges, France.
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Changes in the arabinoxylan fraction of wheat grain during alcohol production. Food Chem 2016; 221:1754-1762. [PMID: 27979157 PMCID: PMC5176037 DOI: 10.1016/j.foodchem.2016.10.109] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Revised: 10/13/2016] [Accepted: 10/23/2016] [Indexed: 01/16/2023]
Abstract
Laboratory produced DDGS samples were compared with commercial samples from a distillery and a biofuel plant. Changes in structure, solubility and content of arabinoxylan (AX) was determined. The distillation process results in a relative increase of AX content compared to the starting material. The heating and drying processes involved in the production of DDGS lead to an increased solubility and viscosity of water-extractable AX. Production of DDGS results in structural changes to the AX. There is a decrease in 2- and 3-linked arabinose oligosaccharides, that contributes to around a 50% reduction in arabinosylation in DDGS compared with the starting grains. The current study shows that laboratory-scale DDGS provide an accurate representation of the commercial scale and that the AX composition of DDGS is consistently uniform irrespective of starting material. The uniformity of DDGS and thin stillage makes them a good potential source of AX for production of prebiotics or other novel products.
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The Glycoside Hydrolase Family 8 Reducing-End Xylose-Releasing Exo-oligoxylanase Rex8A from Paenibacillus barcinonensis BP-23 Is Active on Branched Xylooligosaccharides. Appl Environ Microbiol 2016; 82:5116-24. [PMID: 27316951 DOI: 10.1128/aem.01329-16] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Accepted: 05/27/2016] [Indexed: 01/06/2023] Open
Abstract
UNLABELLED A GH8 family enzyme involved in xylan depolymerization has been characterized. The enzyme, Rex8A, is a reducing-end xylose-releasing exo-oligoxylanase (Rex) that efficiently hydrolyzes xylooligosaccharides and shows minor activity on polymeric xylan. Rex8A hydrolyzes xylooligomers of 3 to 6 xylose units to xylose and xylobiose in long-term incubations. Kinetic constants of Rex8A were determined on xylotriose, showing a Km of 1.64 ± 0.03 mM and a kcat value of 118.8 s(-1) Besides linear xylooligosaccharides, the enzyme hydrolyzed decorated xylooligomers. The catalytic activity on branched xylooligosaccharides, i.e., the release of xylose from the reducing end, is a newly described trait of xylose-releasing exo-oligoxylanases, as the exo-activity on these substrates has not been reported for the few of these enzymes characterized to date. Modeling of the three-dimensional (3D) structure of Rex8A shows an (α/α)6 barrel fold where the loops connecting the α-helices contour the active site. These loops, which show high sequence diversity among GH8 enzymes, shape a catalytic cleft with a -2 subsite that can accommodate methyl-glucuronic acid decorations. The hydrolytic ability of Rex8A on branched oligomers can be crucial for the complete depolymerization of highly substituted xylans, which is indispensable to accomplish biomass deconstruction and to generate efficient catalysts. IMPORTANCE A GH8 family enzyme involved in xylan depolymerization has been characterized. The Rex8A enzyme from Paenibacillus barcinonensis is involved in depolymerization of glucuronoxylan, a major component of the lignocellulosic substrates. The study shows that Rex8A is a reducing-end xylose-releasing exo-oligoxylanase that efficiently hydrolyzes xylose from neutral and acidic xylooligosaccharides generated by the action of other xylanases also secreted by the strain. The activity of a Rex enzyme on branched xylooligosaccharides has not been described to date. This report provides original and useful information on the properties of a new example of the rarely studied Rex enzymes. Depolymerization of highly substituted xylans is crucial for biomass valorization as a platform for generation of biofuels, chemicals, and solvents.
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Gong W, Zhang H, Tian L, Liu S, Wu X, Li F, Wang L. Determination of the modes of action and synergies of xylanases by analysis of xylooligosaccharide profiles over time using fluorescence-assisted carbohydrate electrophoresis. Electrophoresis 2016; 37:1640-50. [PMID: 27060349 DOI: 10.1002/elps.201600041] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2016] [Revised: 03/21/2016] [Accepted: 03/23/2016] [Indexed: 01/06/2023]
Abstract
The structure of xylan, which has a 1,4-linked β-xylose backbone with various substituents, is much more heterogeneous and complex than that of cellulose. Because of this, complete degradation of xylan needs a large number of enzymes that includes GH10, GH11, and GH3 family xylanases together with auxiliary enzymes. Fluorescence-assisted carbohydrate electrophoresis (FACE) is able to accurately differentiate unsubstituted and substituted xylooligosaccharides (XOS) in the heterogeneous products generated by different xylanases and allows changes in concentrations of specific XOS to be analyzed quantitatively. Based on a quantitative analysis of XOS profiles over time using FACE, we have demonstrated that GH10 and GH11 family xylanases immediately degrade xylan into sizeable XOS, which are converted into smaller XOS in a much lower speed. The shortest substituted XOS produced by hydrolysis of the substituted xylan backbone by GH10 and GH11 family xylanases were MeGlcA(2) Xyl3 and MeGlcA(2) Xyl4 , respectively. The unsubstituted xylan backbone was degraded into xylose, xylobiose, and xylotriose by both GH10 and GH11 family xylanases; the product profiles are not family-specific but, instead, depend on different subsite binding affinities in the active sites of individual enzymes. Synergystic action between xylanases and β-xylosidase degraded MeGlcA(2) Xyl4 into xylose and MeGlcA(2) Xyl3 but further degradation of MeGlcA(2) Xyl3 required additional enzymes. Synergy between xylanases and β-xylosidase was also found to significantly accelerate the conversion of XOS into xylose.
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Affiliation(s)
- Weili Gong
- The State Key Laboratory of Microbial Technology, Shandong University, Jinan, Shandong, P. R. China
| | - Huaiqiang Zhang
- The State Key Laboratory of Microbial Technology, Shandong University, Jinan, Shandong, P. R. China
| | - Li Tian
- The State Key Laboratory of Microbial Technology, Shandong University, Jinan, Shandong, P. R. China
| | - Shijia Liu
- Taishan College, Shandong University, Jinan, Shandong, P. R. China
| | - Xiuyun Wu
- The State Key Laboratory of Microbial Technology, Shandong University, Jinan, Shandong, P. R. China
| | - Fuli Li
- Key Laboratory of Biofuels, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, P. R. China
| | - Lushan Wang
- The State Key Laboratory of Microbial Technology, Shandong University, Jinan, Shandong, P. R. China
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33
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Revisiting the structural features of arabinoxylans from brewers’ spent grain. Carbohydr Polym 2016; 139:167-76. [DOI: 10.1016/j.carbpol.2015.12.006] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Revised: 11/29/2015] [Accepted: 12/03/2015] [Indexed: 11/19/2022]
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Cobucci-Ponzano B, Strazzulli A, Iacono R, Masturzo G, Giglio R, Rossi M, Moracci M. Novel thermophilic hemicellulases for the conversion of lignocellulose for second generation biorefineries. Enzyme Microb Technol 2015. [PMID: 26215346 DOI: 10.1016/j.enzmictec.2015.06.014] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The biotransformation of lignocellulose biomasses into fermentable sugars is a very complex procedure including, as one of the most critical steps, the (hemi) cellulose hydrolysis by specific enzymatic cocktails. We explored here, the potential of stable glycoside hydrolases from thermophilic organisms, so far not used in commercial enzymatic preparations, for the conversion of glucuronoxylan, the major hemicellulose of several energy crops. Searches in the genomes of thermophilic bacteria led to the identification, efficient production, and detailed characterization of novel xylanase and α-glucuronidase from Alicyclobacillus acidocaldarius (GH10-XA and GH67-GA, respectively) and a α-glucuronidase from Caldicellulosiruptor saccharolyticus (GH67-GC). Remarkably, GH10-XA, if compared to other thermophilic xylanases from this family, coupled good specificity on beechwood xylan and the best stability at 65 °C (3.5 days). In addition, GH67-GC was the most stable α-glucuronidases from this family and the first able to hydrolyse both aldouronic acid and aryl-α-glucuronic acid substrates. These enzymes, led to the very efficient hydrolysis of beechwood xylan by using 7- to 9-fold less protein (concentrations <0.3 μM) and in much less reaction time (2h vs 12h) if compared to other known biotransformations catalyzed by thermophilic enzymes. In addition, remarkably, together with a thermophilic β-xylosidase, they catalyzed the production of xylose from the smart cooking pre-treated biomass of one of the most promising energy crops for second generation biorefineries. We demonstrated that search by the CAZy Data Bank of currently available genomes and detailed enzymatic characterization of recombinant enzymes allow the identification of glycoside hydrolases with novel and interesting properties and applications.
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Affiliation(s)
- Beatrice Cobucci-Ponzano
- Institute of Biosciences and Bioresources, National Research Council of Italy, Via P. Castellino 111, 80131 Naples, Italy.
| | - Andrea Strazzulli
- Institute of Biosciences and Bioresources, National Research Council of Italy, Via P. Castellino 111, 80131 Naples, Italy.
| | - Roberta Iacono
- Institute of Biosciences and Bioresources, National Research Council of Italy, Via P. Castellino 111, 80131 Naples, Italy.
| | - Giuseppe Masturzo
- Institute of Biosciences and Bioresources, National Research Council of Italy, Via P. Castellino 111, 80131 Naples, Italy.
| | - Rosa Giglio
- Institute of Biosciences and Bioresources, National Research Council of Italy, Via P. Castellino 111, 80131 Naples, Italy.
| | - Mosè Rossi
- Institute of Biosciences and Bioresources, National Research Council of Italy, Via P. Castellino 111, 80131 Naples, Italy.
| | - Marco Moracci
- Institute of Biosciences and Bioresources, National Research Council of Italy, Via P. Castellino 111, 80131 Naples, Italy.
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Sainz-Polo MA, Valenzuela SV, González B, Pastor FIJ, Sanz-Aparicio J. Structural analysis of glucuronoxylan-specific Xyn30D and its attached CBM35 domain gives insights into the role of modularity in specificity. J Biol Chem 2014; 289:31088-101. [PMID: 25202007 DOI: 10.1074/jbc.m114.597732] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Glucuronoxylanase Xyn30D is a modular enzyme containing a family 30 glycoside hydrolase catalytic domain and an attached carbohydrate binding module of the CBM35 family. We present here the three-dimensional structure of the full-length Xyn30D at 2.4 Å resolution. The catalytic domain folds into an (α/β)8 barrel with an associated β-structure, whereas the attached CBM35 displays a jellyroll β-sandwich including two calcium ions. Although both domains fold in an independent manner, the linker region makes polar interactions with the catalytic domain, allowing a moderate flexibility. The ancillary Xyn30D-CBM35 domain has been expressed and crystallized, and its binding abilities have been investigated by soaking experiments. Only glucuronic acid-containing ligands produced complexes, and their structures have been solved. A calcium-dependent glucuronic acid binding site shows distinctive structural features as compared with other uronic acid-specific CBM35s, because the presence of two aromatic residues delineates a wider pocket. The nonconserved Glu(129) makes a bidentate link to calcium and defines region E, previously identified as specificity hot spot. The molecular surface of Xyn30D-CBM35 shows a unique stretch of negative charge distribution extending from its binding pocket that might indicate some oriented interaction with its target substrate. The binding ability of Xyn30D-CBM35 to different xylans was analyzed by affinity gel electrophoresis. Some binding was observed with rye glucuronoarabinoxylan in presence of calcium chelating EDTA, which would indicate that Xyn30D-CBM35 might establish interaction to other components of xylan, such as arabinose decorations of glucuronoarabinoxylan. A role in depolymerization of highly substituted chemically complex xylans is proposed.
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Affiliation(s)
- M Angela Sainz-Polo
- From the Departamento de Cristalografía y Biología Estructural, Instituto de Química-Física Rocasolano, CSIC, 28006 Madrid, Spain and
| | - Susana Valeria Valenzuela
- the Departamento de Microbiología, Facultad de Biología. Universidad de Barcelona. 08028 Barcelona, Spain
| | - Beatriz González
- From the Departamento de Cristalografía y Biología Estructural, Instituto de Química-Física Rocasolano, CSIC, 28006 Madrid, Spain and
| | - F I Javier Pastor
- the Departamento de Microbiología, Facultad de Biología. Universidad de Barcelona. 08028 Barcelona, Spain
| | - Julia Sanz-Aparicio
- From the Departamento de Cristalografía y Biología Estructural, Instituto de Química-Física Rocasolano, CSIC, 28006 Madrid, Spain and
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Jia X, Mi S, Wang J, Qiao W, Peng X, Han Y. Insight into glycoside hydrolases for debranched xylan degradation from extremely thermophilic bacterium Caldicellulosiruptor lactoaceticus. PLoS One 2014; 9:e106482. [PMID: 25184498 PMCID: PMC4153629 DOI: 10.1371/journal.pone.0106482] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2014] [Accepted: 08/05/2014] [Indexed: 11/18/2022] Open
Abstract
Caldicellulosiruptor lactoaceticus 6A, an anaerobic and extremely thermophilic bacterium, uses natural xylan as carbon source. The encoded genes of C. lactoaceticus 6A for glycoside hydrolase (GH) provide a platform for xylan degradation. The GH family 10 xylanase (Xyn10A) and GH67 α-glucuronidase (Agu67A) from C. lactoaceticus 6A were heterologously expressed, purified and characterized. Both Xyn10A and Agu67A are predicted as intracellular enzymes as no signal peptides identified. Xyn10A and Agu67A had molecular weight of 47.0 kDa and 80.0 kDa respectively as determined by SDS-PAGE, while both appeared as homodimer when analyzed by gel filtration. Xyn10A displayed the highest activity at 80 °C and pH 6.5, as 75 °C and pH 6.5 for Agu67A. Xyn10A had good stability at 75 °C, 80 °C, and pH 4.5-8.5, respectively, and was sensitive to various metal ions and reagents. Xyn10A possessed hydrolytic activity towards xylo-oligosaccharides (XOs) and beechwood xylan. At optimum conditions, the specific activity of Xyn10A was 44.6 IU/mg with beechwood xylan as substrate, and liberated branched XOs, xylobiose, and xylose. Agu67A was active on branched XOs with methyl-glucuronic acids (MeGlcA) sub-chains, and primarily generated XOs equivalents and MeGlcA. The specific activity of Agu67A was 1.3 IU/mg with aldobiouronic acid as substrate. The synergistic action of Xyn10A and Agu67A was observed with MeGlcA branched XOs and xylan as substrates, both backbone and branched chain of substrates were degraded, and liberated xylose, xylobiose, and MeGlcA. The synergism of Xyn10A and Agu67A provided not only a thermophilic method for natural xylan degradation, but also insight into the mechanisms for xylan utilization of C. lactoaceticus.
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Affiliation(s)
- Xiaojing Jia
- National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, China
| | - Shuofu Mi
- National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, China
| | - Jinzhi Wang
- Institute of Agro-food Science and Technology, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Weibo Qiao
- National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, China
- College of Biosciences and Biotechnology, Shenyang Agricultural University, Shenyang, China
| | - Xiaowei Peng
- National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, China
| | - Yejun Han
- National Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing, China
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MALDI-TOF MS analysis of cellodextrins and xylo-oligosaccharides produced by hindgut homogenates of Reticulitermes santonensis. Molecules 2014; 19:4578-94. [PMID: 24731986 PMCID: PMC6270808 DOI: 10.3390/molecules19044578] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2014] [Revised: 04/02/2014] [Accepted: 04/04/2014] [Indexed: 12/03/2022] Open
Abstract
Hindgut homogenates of the termite Reticulitermes santonensis were incubated with carboxymethyl cellulose (CMC), crystalline celluloses or xylan substrates. Hydrolysates were analyzed with matrix-assisted laser desorption/ionization coupled to time-of-flight mass spectrometry (MALDI-TOF MS). The method was first set up using acid hydrolysis analysis to characterize non-enzymatic profiles. Commercial enzymes of Trichoderma reesei or T. longibrachiatum were also tested to validate the enzymatic hydrolysis analysis. For CMC hydrolysis, data processing and visual display were optimized to obtain comprehensive profiles and allow rapid comparison and evaluation of enzymatic selectivity, according to the number of substituents of each hydrolysis product. Oligosaccharides with degrees of polymerization (DPs) ranging from three to 12 were measured from CMC and the enzymatic selectivity was demonstrated. Neutral and acidic xylo-oligosaccharides with DPs ranging from three to 11 were measured from xylan substrate. These results are of interest for lignocellulose biomass valorization and demonstrated the potential of termites and their symbiotic microbiota as a source of interesting enzymes for oligosaccharides production.
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38
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Chong SL, Virkki L, Maaheimo H, Juvonen M, Derba-Maceluch M, Koutaniemi S, Roach M, Sundberg B, Tuomainen P, Mellerowicz EJ, Tenkanen M. O-Acetylation of glucuronoxylan in Arabidopsis thaliana wild type and its change in xylan biosynthesis mutants. Glycobiology 2014; 24:494-506. [DOI: 10.1093/glycob/cwu017] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
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Valenzuela SV, Diaz P, Pastor FIJ. Xyn11E from Paenibacillus barcinonensis BP-23: a LppX-chaperone-dependent xylanase with potential for upgrading paper pulps. Appl Microbiol Biotechnol 2014; 98:5949-57. [DOI: 10.1007/s00253-014-5565-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Revised: 12/20/2013] [Accepted: 01/21/2014] [Indexed: 12/21/2022]
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40
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Zhao L, Meng K, Shi P, Bai Y, Luo H, Huang H, Wang Y, Yang P, Yao B. A novel thermophilic xylanase from Achaetomium sp. Xz-8 with high catalytic efficiency and application potentials in the brewing and other industries. Process Biochem 2013. [DOI: 10.1016/j.procbio.2013.08.020] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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41
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Takahashi Y, Kawabata H, Murakami S. Analysis of functional xylanases in xylan degradation by Aspergillus niger E-1 and characterization of the GH family 10 xylanase XynVII. SPRINGERPLUS 2013; 2:447. [PMID: 24083101 PMCID: PMC3786065 DOI: 10.1186/2193-1801-2-447] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/30/2013] [Accepted: 09/04/2013] [Indexed: 11/10/2022]
Abstract
Xylanases produced by Aspergillus niger are industrially important and many types of xylanases have been reported. Individual xylanases have been well studied for their enzymatic properties, gene cloning, and heterologous expression. However, less attention has been paid to the relationship between xylanase genes carried on the A. niger genome and xylanases produced by A. niger strains. Therefore, we examined xylanase genes encoded on the genome of A. niger E-1 and xylanases produced in culture. Seven putative xylanase genes, xynI–VII (named in ascending order of the molecular masses of the deduced amino acid sequences), were amplified from the strain E-1 genome using primers designed from the genome sequence of A. niger CBS 513.88 by PCR and phylogenetically classified into three clusters. Additionally, culture supernatant analysis by DE52 anion–exchange column chromatography revealed that this strain produced three xylanases, XynII, XynIII, and XynVII, which were identified by N-terminal amino acid sequencing and MALDI-TOF-MS analyses, in culture when gown in 0.5% xylan medium supplemented with 50 mM succinate. Furthermore, XynVII, the only GH family 10 xylanase in A. niger E-1, was purified and characterized. The purified enzyme showed a single band with a molecular mass of 35 kDa by SDS-PAGE. The highest activity of purified XynVII was observed at 55°C and pH 5.5. The enzyme was stable in the broad pH range of 3–10 and up to 60°C and was resistant to most metal ions and modifying regents. XynVII showed high specificity against beechwood xylan with Km and Vmax values of 2.8 mg mL–1 and 127 μmol min–1mg–1, respectively. TLC and MALDI-TOF-MS analyses showed that the final hydrolyzed products of the enzyme from beechwood xylan were xylose, xylobiose, and xylotriose substituted with a 4-o-metylglucuronic acid residue.
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Affiliation(s)
- Yui Takahashi
- Department of Agricultural Chemistry, Graduate School of Agriculture, Meiji University, 1-1-1, Higashimita, Tama-ku, Kawasaki, 214-8571 Japan
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Hu J, Arantes V, Pribowo A, Saddler JN. The synergistic action of accessory enzymes enhances the hydrolytic potential of a "cellulase mixture" but is highly substrate specific. BIOTECHNOLOGY FOR BIOFUELS 2013; 6:112. [PMID: 23915398 PMCID: PMC3750293 DOI: 10.1186/1754-6834-6-112] [Citation(s) in RCA: 133] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2013] [Accepted: 08/02/2013] [Indexed: 05/05/2023]
Abstract
BACKGROUND Currently, the amount of protein/enzyme required to achieve effective cellulose hydrolysis is still too high. One way to reduce the amount of protein/enzyme required is to formulate a more efficient enzyme cocktail by adding so-called accessory enzymes such as xylanase, lytic polysaccharide monooxygenase (AA9, formerly known as GH61), etc., to the cellulase mixture. Previous work has shown the strong synergism that can occur between cellulase and xylanase mixtures during the hydrolysis of steam pretreated corn stover, requiring lower protein loading to achieve effective hydrolysis. However, relatively high loadings of xylanases were required. When family 10 and 11 endo-xylanases and family 5 xyloglucanase were supplemented to a commercial cellulase mixture varying degrees of improved hydrolysis over a range of pretreated, lignocellulosic substrates were observed. RESULTS The potential synergistic interactions between cellulase monocomponents and hemicellulases from family 10 and 11 endo-xylanases (GH10 EX and GH11 EX) and family 5 xyloglucanase (GH5 XG), during hydrolysis of various steam pretreated lignocellulosic substrates, were assessed. It was apparent that the hydrolytic activity of cellulase monocomponents was enhanced by the addition of accessory enzymes although the "boosting" effect was highly substrate specific. The GH10 EX and GH5 XG both exhibited broad substrate specificity and showed strong synergistic interaction with the cellulases when added individually. The GH10 EX was more effective on steam pretreated agriculture residues and hardwood substrates whereas GH5 XG addition was more effective on softwood substrates. The synergistic interaction between GH10 EX and GH5 XG when added together further enhanced the hydrolytic activity of the cellulase enzymes over a range of pretreated lignocellulosic substrates. GH10 EX addition could also stimulate further cellulose hydrolysis when added to the hydrolysis reactions when the rate of hydrolysis had levelled off. CONCLUSIONS Endo-xylanases and xyloglucanases interacted synergistically with cellulases to improve the hydrolysis of a range of pretreated lignocellulosic substrates. However, the extent of improved hydrolysis was highly substrate dependent. It appears that those accessory enzymes, such as GH10 EX and GH5 XG, with broader substrate specificities promoted the greatest improvements in the hydrolytic performance of the cellulase mixture on all of the pretreated biomass substrates.
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Affiliation(s)
- Jinguang Hu
- Forestry Products Biotechnology/Bioenergy Group, Wood Science Department, University of British Columbia, 2424 Main Mall, Vancouver, BC V6T 1Z4, Canada
| | - Valdeir Arantes
- Forestry Products Biotechnology/Bioenergy Group, Wood Science Department, University of British Columbia, 2424 Main Mall, Vancouver, BC V6T 1Z4, Canada
| | - Amadeus Pribowo
- Forestry Products Biotechnology/Bioenergy Group, Wood Science Department, University of British Columbia, 2424 Main Mall, Vancouver, BC V6T 1Z4, Canada
| | - Jack N Saddler
- Forestry Products Biotechnology/Bioenergy Group, Wood Science Department, University of British Columbia, 2424 Main Mall, Vancouver, BC V6T 1Z4, Canada
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Novel structural features of xylanase A1 from Paenibacillus sp. JDR-2. J Struct Biol 2012; 180:303-11. [PMID: 23000703 DOI: 10.1016/j.jsb.2012.09.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2012] [Revised: 08/28/2012] [Accepted: 09/03/2012] [Indexed: 11/24/2022]
Abstract
The Gram-positive bacterium Paenibacillus sp. JDR-2 (PbJDR2) has been shown to have novel properties in the utilization of the abundant but chemically complex hemicellulosic sugar glucuronoxylan. Xylanase A1 of PbJDR2 (PbXynA1) has been implicated in an efficient process in which extracellular depolymerization of this polysaccharide is coupled to assimilation and intracellular metabolism. PbXynA1is a 154kDa cell wall anchored multimodular glycosyl hydrolase family 10 (GH10) xylanase. In this work, the 38kDa catalytic module of PbXynA1 has been structurally characterized revealing several new features not previously observed in structures of GH10 xylanases. These features are thought to facilitate hydrolysis of highly substituted, chemically complex xylans that may be the form found in close proximity to the cell wall of PbJDR2, an organism shown to have a preference for growth on polymeric glucuronoxylan.
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Peng F, Peng P, Xu F, Sun RC. Fractional purification and bioconversion of hemicelluloses. Biotechnol Adv 2012; 30:879-903. [PMID: 22306329 DOI: 10.1016/j.biotechadv.2012.01.018] [Citation(s) in RCA: 180] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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Modular glucuronoxylan-specific xylanase with a family CBM35 carbohydrate-binding module. Appl Environ Microbiol 2012; 78:3923-31. [PMID: 22447606 DOI: 10.1128/aem.07932-11] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Xyn30D from the xylanolytic strain Paenibacillus barcinonensis has been identified and characterized. The enzyme shows a modular structure comprising a catalytic module family 30 (GH30) and a carbohydrate-binding module family 35 (CBM35). Like GH30 xylanases, recombinant Xyn30D efficiently hydrolyzed glucuronoxylans and methyl-glucuronic acid branched xylooligosaccharides but showed no catalytic activity on arabinose-substituted xylans. Kinetic parameters of Xyn30D were determined on beechwood xylan, showing a K(m) of 14.72 mg/ml and a k(cat) value of 1,510 min(-1). The multidomain structure of Xyn30D clearly distinguishes it from the GH30 xylanases characterized to date, which are single-domain enzymes. The modules of the enzyme were individually expressed in a recombinant host and characterized. The isolated GH30 catalytic module showed specific activity, mode of action on xylan, and kinetic parameters that were similar to those of the full-length enzyme. Computer modeling of the three-dimensional structure of Xyn30D showed that the catalytic module is comprised of a common (β/α)(8) barrel linked to a side-associated β-structure. Several derivatives of the catalytic module with decreasing deletions of this associated structure were constructed. None of them showed catalytic activity, indicating the importance of the side β-structure in the catalysis of Xyn30D. Binding properties of the isolated carbohydrate-binding module were analyzed by affinity gel electrophoresis, which showed that the CBM35 of the enzyme binds to soluble glucuronoxylans and arabinoxylans. Analysis by isothermal titration calorimetry showed that CBM35 binds to glucuronic acid and requires calcium ions for binding. Occurrence of a CBM35 in a glucuronoxylan-specific xylanase is a differential trait of the enzyme characterized.
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Yamasaki T, Enomoto A, Kato A, Ishii T, Kameyama M, Anzai H, Shimizu K. Enzymatically derived aldouronic acids from Cryptomeria japonica arabinoglucuronoxylan. Carbohydr Polym 2012. [DOI: 10.1016/j.carbpol.2011.09.033] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Chong SL, Battaglia E, Coutinho PM, Henrissat B, Tenkanen M, de Vries RP. The α-glucuronidase Agu1 from Schizophyllum commune is a member of a novel glycoside hydrolase family (GH115). Appl Microbiol Biotechnol 2011; 90:1323-32. [DOI: 10.1007/s00253-011-3157-y] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2010] [Revised: 01/28/2011] [Accepted: 01/29/2011] [Indexed: 10/18/2022]
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St John FJ, Hurlbert JC, Rice JD, Preston JF, Pozharski E. Ligand bound structures of a glycosyl hydrolase family 30 glucuronoxylan xylanohydrolase. J Mol Biol 2011; 407:92-109. [PMID: 21256135 DOI: 10.1016/j.jmb.2011.01.010] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2010] [Revised: 01/04/2011] [Accepted: 01/05/2011] [Indexed: 10/18/2022]
Abstract
Xylanases of glycosyl hydrolase family 30 (GH30) have been shown to cleave β-1,4 linkages of 4-O-methylglucuronoxylan (MeGX(n)) as directed by the position along the xylan chain of an α-1,2-linked 4-O-methylglucuronate (MeGA) moiety. Complete hydrolysis of MeGX(n) by these enzymes results in singly substituted aldouronates having a 4-O-methylglucuronate moiety linked to a xylose penultimate from the reducing terminal xylose and some number of xylose residues toward the nonreducing terminus. This novel mode of action distinguishes GH30 xylanases from the more common xylanase families that cleave MeGX(n) in accessible regions. To help understand this unique biochemical function, we have determined the structure of XynC in its native and ligand-bound forms. XynC structure models derived from diffraction data of XynC crystal soaks with the simple sugar glucuronate (GA) and the tetrameric sugar 4-O-methyl-aldotetrauronate resulted in models containing GA and 4-O-methyl-aldotriuronate, respectively. Each is observed in two locations within XynC surface openings. Ligand coordination occurs within the XynC catalytic substrate binding cleft and on the structurally fused side β-domain, demonstrating a substrate targeting role for this putative carbohydrate binding module. Structural data reveal that GA acts as a primary functional appendage for recognition and hydrolysis of the MeGX(n) polymer by the protein. This work compares the structure of XynC with a previously reported homologous enzyme, XynA, from Erwinia chrysanthemi and analyzes the ligand binding sites. Our results identify the molecular interactions that define the unique function of XynC and homologous GH30 enzymes.
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Affiliation(s)
- Franz J St John
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, Baltimore, MD 21201, USA.
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Sharma M, Chadha BS, Saini HS. Purification and characterization of two thermostable xylanases from Malbranchea flava active under alkaline conditions. BIORESOURCE TECHNOLOGY 2010; 101:8834-8842. [PMID: 20630749 DOI: 10.1016/j.biortech.2010.06.071] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2010] [Revised: 05/31/2010] [Accepted: 06/11/2010] [Indexed: 05/29/2023]
Abstract
Two xylanases, MFX I and MFX II, from the thermophilic fungus Malbranchea flava MTCC 4889 with molecular masses of 25.2 and 30kDa and pIs of 4.5 and 3.7, respectively were purified to homogeneity. The xylanases were optimally active at pH 9.0 and at 60 degrees C, exhibited a half-life of 4h at 60 degrees C, and showed distinct mode of action and product profiles when applied to birchwood, oat spelt, and larchwood xylan, and to wheat and rye arabinoxylan. The xylanases were most active on larchwood xylan with K(m) values of 1.25 and 3.7mg/ml. K(cat)/K(m) values suggested that the xylanases preferentially hydrolyzed rye arabinoxylan. LC-MS/MS (liquid chromatography/mass spectrometry) analysis of tryptic digests of MFX I and MFX II revealed similarity with known fungal xylanases and suggests that that they belonged to the GH 11 and 10 glycosyl hydrolase super families, respectively. These xylanases can potentially be used in enzyme-assisted bleaching of the pulp derived from agro-residues, as well as production of xylooligosaccharides for pre-biotic functional food applications.
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Affiliation(s)
- Manju Sharma
- Department of Microbiology, Guru Nanak Dev University, Amritsar, Punjab, India.
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Najmudin S, Pinheiro BA, Prates JAM, Gilbert HJ, Romão MJ, Fontes CMGA. Putting an N-terminal end to the Clostridium thermocellum xylanase Xyn10B story: crystal structure of the CBM22-1-GH10 modules complexed with xylohexaose. J Struct Biol 2010; 172:353-62. [PMID: 20682344 DOI: 10.1016/j.jsb.2010.07.009] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2010] [Revised: 07/26/2010] [Accepted: 07/29/2010] [Indexed: 10/19/2022]
Abstract
In general, plant cell wall degrading enzymes are modular proteins containing catalytic domains linked to one or more non-catalytic carbohydrate-binding modules (CBMs). Xyn10B from Clostridium thermocellum is a typical modular enzyme containing an N-terminal family 22 CBM (CBM22-1), a family 10 glycoside hydrolase catalytic domain (GH10), a second CBM22 (CBM22-2), a dockerin sequence and a C-terminal family 1 carbohydrate esterase (CE1) catalytic domain. The structure of the N-terminal bi-modular CBM22-1-GH10 component of Xyn10B has been determined using a SeMet derivative by SAD to 2.5Å. The data was extended to 2.0Å for the non-SeMet mutant complexed with xylohexaose. CBM22-1-GH10 is a 60kDa protein with an E337A mutation to render the GH10 subunit inactive. Three of the six xylose residues of xylohexaose are shown to be bound in the inactivated GH10 substrate binding cleft, with the other three sugars presumably disordered in the solvent channel. The protein is a dimer in the asymmetric unit with extensive surface contacts between the two GH10 modules and between the CBM22-1 and GH10 modules. Residues from helix H4 of the GH10 module provide the major contacts by fitting into the minor groove of the CBM22-1 module. The orientation of CBM22-1 is such that it would allow the substrate to be loosely bound and subsequently delivered to the active site in a processive manner.
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Affiliation(s)
- Shabir Najmudin
- CIISA - Faculdade de Medicina Veterinária, Universidade Técnica de Lisboa, Avenida da Universidade Técnica, 1300-477 Lisboa, Portugal.
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