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Shimada N, Kameyama A, Watanabe M, Sahara T, Matsuzawa T. Identification and characterization of xyloglucan-degradation related α-1,2-l-fucosidase in Aspergillus oryzae. J Biosci Bioeng 2024:S1389-1723(24)00159-2. [PMID: 38871579 DOI: 10.1016/j.jbiosc.2024.05.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2024] [Revised: 05/14/2024] [Accepted: 05/25/2024] [Indexed: 06/15/2024]
Abstract
Xyloglucan in plant cell walls has complex side-chain structures; Aspergillus oryzae produces various enzymes to degrade and assimilate xyloglucan. In this study, we identified and characterized α-1,2-l-fucosidase (AfcA) which is involved in xyloglucan degradation in A. oryzae. AfcA expression was induced in the presence of xyloglucan oligosaccharides. AfcA showed specific activity toward α-(1→2)-linked l-fucopyranosyl residues attached to the side chains of xyloglucan oligosaccharides and milk oligosaccharides, but not toward α-(1→3)-, α-(1→4)-, and α-(1→6)-linked l-fucopyranosyl residues. As fucopyranosyl residues in the side chains of xyloglucan oligosaccharides prevent the degradation of xyloglucan oligosaccharides by isoprimeverose-producing oligoxyloglucan hydrolase and β-galactosidase, the cooperative action of AfcA, isoprimeverose-producing oligoxyloglucan hydrolase, and β-galactosidase play a key role in degrading fucosylated xyloglucan in A. oryzae.
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Affiliation(s)
- Naoki Shimada
- Department of Applied Biological Science, Faculty of Agriculture, Kagawa University, 2393 Ikenobe, Miki, Kagawa 761-0795, Japan
| | - Akihiko Kameyama
- Cellular and Molecular Biotechnology Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan
| | - Masahiro Watanabe
- Research Institute for Sustainable Chemistry, National Institute of Advanced Industrial Science and Technology (AIST), 3-11-32 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-0046, Japan
| | - Takehiko Sahara
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Higashi, Tsukuba, Ibaraki 305-8566, Japan
| | - Tomohiko Matsuzawa
- Department of Applied Biological Science, Faculty of Agriculture, Kagawa University, 2393 Ikenobe, Miki, Kagawa 761-0795, Japan.
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Matsuzawa T. Plant polysaccharide degradation-related enzymes in Aspergillus oryzae. Biosci Biotechnol Biochem 2024; 88:276-282. [PMID: 38066701 DOI: 10.1093/bbb/zbad177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Accepted: 12/06/2023] [Indexed: 02/22/2024]
Abstract
Plants synthesize large amounts of stored and structural polysaccharides. Aspergillus oryzae is used in traditional Japanese fermentation and produces many types of plant polysaccharide degradation-related enzymes. The carbohydrate-active enzymes of A. oryzae are important in the fermentation process and biotechnological applications. Because plant polysaccharides have a complex structure, cooperative and synergistic actions of enzymes are crucial for the degradation of plant polysaccharides. For example, the cooperative action of isoprimeverose-producing oligoxyloglucan hydrolase, β-galactosidase, and α-xylosidase is important for the degradation of xyloglucan, and A. oryzae coordinates these enzymes at the expression level. In this review, I focus on the plant polysaccharide degradation-related enzymes identified in A. oryzae.
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Affiliation(s)
- Tomohiko Matsuzawa
- Department of Applied Biological Science, Faculty of Agriculture, Kagawa University, Miki, Kagawa, Japan
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Matsuzawa T, Nakamichi Y, Shimada N. Identification and Characterization of Novel Intracellular α-Xylosidase in Aspergillus oryzae. J Appl Glycosci (1999) 2023; 70:119-125. [PMID: 38239767 PMCID: PMC10792220 DOI: 10.5458/jag.jag.jag-2023_0007] [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: 06/08/2023] [Accepted: 09/03/2023] [Indexed: 01/22/2024] Open
Abstract
α-Xylosidase releases xylopyranosyl side chains from xyloglucan oligosaccharides and is vital for xyloglucan degradation. Previously, we identified and characterized two α-xylosidases, intracellular AxyA and extracellular AxyB, in Aspergillus oryzae. In this study, we identified a third α-xylosidase, termed AxyC, in A. oryzae. These three A. oryzae α-xylosidases belong to the glycoside hydrolase family 31, but there are clear differences in substrate specificity. Both AxyA and AxyB showed much higher hydrolytic activity toward isoprimeverose (α-D-xylopyranosyl-1,6-glucose) than p-nitrophenyl α-D-xylopyranoside. In contrast, the specific activity of AxyC toward the p-nitrophenyl substrate was approximately 950-fold higher than that toward isoprimeverose. Our study revealed that there are multiple α-xylosidases with different substrate specificities in A. oryzae.
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Affiliation(s)
- Tomohiko Matsuzawa
- Department of Applied Biological Science, Faculty of Agriculture, Kagawa University
| | - Yusuke Nakamichi
- Research Institute for Sustainable Chemistry, National Institute of Advanced Industrial Science and Technology (AIST)
| | - Naoki Shimada
- Department of Applied Biological Science, Faculty of Agriculture, Kagawa University
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Li J, Wiebenga A, Lipzen A, Ng V, Tejomurthula S, Zhang Y, Grigoriev IV, Peng M, de Vries RP. Comparative Genomics and Transcriptomics Analyses Reveal Divergent Plant Biomass-Degrading Strategies in Fungi. J Fungi (Basel) 2023; 9:860. [PMID: 37623631 PMCID: PMC10455118 DOI: 10.3390/jof9080860] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 08/15/2023] [Accepted: 08/16/2023] [Indexed: 08/26/2023] Open
Abstract
Plant biomass is one of the most abundant renewable carbon sources, which holds great potential for replacing current fossil-based production of fuels and chemicals. In nature, fungi can efficiently degrade plant polysaccharides by secreting a broad range of carbohydrate-active enzymes (CAZymes), such as cellulases, hemicellulases, and pectinases. Due to the crucial role of plant biomass-degrading (PBD) CAZymes in fungal growth and related biotechnology applications, investigation of their genomic diversity and transcriptional dynamics has attracted increasing attention. In this project, we systematically compared the genome content of PBD CAZymes in six taxonomically distant species, Aspergillus niger, Aspergillus nidulans, Penicillium subrubescens, Trichoderma reesei, Phanerochaete chrysosporium, and Dichomitus squalens, as well as their transcriptome profiles during growth on nine monosaccharides. Considerable genomic variation and remarkable transcriptomic diversity of CAZymes were identified, implying the preferred carbon source of these fungi and their different methods of transcription regulation. In addition, the specific carbon utilization ability inferred from genomics and transcriptomics was compared with fungal growth profiles on corresponding sugars, to improve our understanding of the conversion process. This study enhances our understanding of genomic and transcriptomic diversity of fungal plant polysaccharide-degrading enzymes and provides new insights into designing enzyme mixtures and metabolic engineering of fungi for related industrial applications.
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Affiliation(s)
- Jiajia Li
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands; (J.L.); (M.P.)
| | - Ad Wiebenga
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands; (J.L.); (M.P.)
| | - Anna Lipzen
- USA Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd., Berkeley, CA 94720, USA; (A.L.); (V.N.); (S.T.); (Y.Z.); (I.V.G.)
| | - Vivian Ng
- USA Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd., Berkeley, CA 94720, USA; (A.L.); (V.N.); (S.T.); (Y.Z.); (I.V.G.)
| | - Sravanthi Tejomurthula
- USA Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd., Berkeley, CA 94720, USA; (A.L.); (V.N.); (S.T.); (Y.Z.); (I.V.G.)
| | - Yu Zhang
- USA Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd., Berkeley, CA 94720, USA; (A.L.); (V.N.); (S.T.); (Y.Z.); (I.V.G.)
| | - Igor V. Grigoriev
- USA Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd., Berkeley, CA 94720, USA; (A.L.); (V.N.); (S.T.); (Y.Z.); (I.V.G.)
- Plant and Microbial Biology, University of California Berkeley, Berkeley, CA 94720, USA
| | - Mao Peng
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands; (J.L.); (M.P.)
| | - Ronald P. de Vries
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands; (J.L.); (M.P.)
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Jin X, Wang JK, Wang Q. Microbial β-glucanases: production, properties, and engineering. World J Microbiol Biotechnol 2023; 39:106. [PMID: 36847914 DOI: 10.1007/s11274-023-03550-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Accepted: 02/14/2023] [Indexed: 03/01/2023]
Abstract
Lignocellulosic biomass, which mainly consists of cellulose and hemicellulose, is the most abundant renewable biopolymer on earth. β-Glucanases are glycoside hydrolases (GHs) that hydrolyze β-glucan, one of the dominant components of the plant cell wall, into cello-oligosaccharides and glucose. Among them, endo-β-1,4-glucanase (EC 3.2.1.4), exo-glucanase/cellobiohydrolase (EC 3.2.1.91), and β-glucosidase (EC 3.2.1.21) play critical roles in the digestion of glucan-like substrates. β-Glucanases have attracted considerable interest within the scientific community due to their applications in the feed, food, and textile industries. In the past decade, there has been considerable progress in the discovery, production, and characterization of novel β-glucanases. Advances in the development of next-generation sequencing techniques, including metagenomics and metatranscriptomics, have unveiled novel β-glucanases isolated from the gastrointestinal microbiota. The study of β-glucanases is beneficial for research and development of commercial products. In this study, we review the classification, properties, and engineering of β-glucanases.
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Affiliation(s)
- Xinyi Jin
- Key Laboratory of Molecular Animal Nutrition, Ministry of Education, Zhejiang University, Hangzhou, 310058, China.,Institute of Dairy Science, College of Animal Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Jia-Kun Wang
- Key Laboratory of Molecular Animal Nutrition, Ministry of Education, Zhejiang University, Hangzhou, 310058, China.,Institute of Dairy Science, College of Animal Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Qian Wang
- Key Laboratory of Molecular Animal Nutrition, Ministry of Education, Zhejiang University, Hangzhou, 310058, China. .,Institute of Dairy Science, College of Animal Sciences, Zhejiang University, Hangzhou, 310058, China.
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Harvey DJ. Analysis of carbohydrates and glycoconjugates by matrix-assisted laser desorption/ionization mass spectrometry: An update for 2019-2020. MASS SPECTROMETRY REVIEWS 2022:e21806. [PMID: 36468275 DOI: 10.1002/mas.21806] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
This review is the tenth update of the original article published in 1999 on the application of matrix-assisted laser desorption/ionization (MALDI) mass spectrometry to the analysis of carbohydrates and glycoconjugates and brings coverage of the literature to the end of 2020. Also included are papers that describe methods appropriate to analysis by MALDI, such as sample preparation techniques, even though the ionization method is not MALDI. The review is basically divided into three sections: (1) general aspects such as theory of the MALDI process, matrices, derivatization, MALDI imaging, fragmentation, quantification and the use of arrays. (2) Applications to various structural types such as oligo- and polysaccharides, glycoproteins, glycolipids, glycosides and biopharmaceuticals, and (3) other areas such as medicine, industrial processes and glycan synthesis where MALDI is extensively used. Much of the material relating to applications is presented in tabular form. The reported work shows increasing use of incorporation of new techniques such as ion mobility and the enormous impact that MALDI imaging is having. MALDI, although invented nearly 40 years ago is still an ideal technique for carbohydrate analysis and advancements in the technique and range of applications show little sign of diminishing.
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Affiliation(s)
- David J Harvey
- Nuffield Department of Medicine, Target Discovery Institute, University of Oxford, Oxford, UK
- Department of Chemistry, University of Oxford, Oxford, Oxfordshire, United Kingdom
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7
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Matsuzawa T, Watanabe M, Nakamichi Y, Akita H, Yaoi K. Structural basis for the catalytic mechanism of the glycoside hydrolase family 3 isoprimeverose-producing oligoxyloglucan hydrolase from Aspergillus oryzae. FEBS Lett 2022; 596:1944-1954. [PMID: 35717558 DOI: 10.1002/1873-3468.14427] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Revised: 06/08/2022] [Accepted: 06/08/2022] [Indexed: 11/07/2022]
Abstract
Aspergillus oryzae isoprimeverose-producing oligoxyloglucan hydrolase (IpeA) releases isoprimeverose units (α-d-xylopyranosyl-(1→6)-d-glucose) from the non-reducing end of xyloglucan oligosaccharides and belongs to glycoside hydrolase family 3. In this paper, we report the X-ray crystal structure of the IpeA complexed with a xyloglucan oligosaccharide, (XXXG: Glc4 Xyl3 ). Trp515 of IpeA plays a critical role in XXXG recognition at positive subsites. In addition, docking simulation of IpeA-XXXG suggested that two Tyr residues (Tyr268 and Tyr445) are involved in the catalytic reaction mechanism of IpeA. Tyr268 plays an important role in product turnover, whereas Tyr445 stabilizes the acid/base Glu524 residue, which serves as a proton donor. Our findings indicate that the substrate recognition machinery of IpeA is specifically adapted to xyloglucan oligosaccharides.
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Affiliation(s)
- Tomohiko Matsuzawa
- Department of Applied Biological Science, Faculty of Agriculture, Kagawa University, Miki-cho, Japan
| | - Masahiro Watanabe
- Research Institute for Sustainable Chemistry, National Institute of Advanced Industrial Science and Technology (AIST), Hiroshima, Japan
| | - Yusuke Nakamichi
- Research Institute for Sustainable Chemistry, National Institute of Advanced Industrial Science and Technology (AIST), Hiroshima, Japan
| | - Hironaga Akita
- Research Institute for Sustainable Chemistry, National Institute of Advanced Industrial Science and Technology (AIST), Hiroshima, Japan
| | - Katsuro Yaoi
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Japan
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8
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Comparison of the Biochemical Properties and Roles in the Xyloglucan-Rich Biomass Degradation of a GH74 Xyloglucanase and Its CBM-Deleted Variant from Thielavia terrestris. Int J Mol Sci 2022; 23:ijms23095276. [PMID: 35563667 PMCID: PMC9103125 DOI: 10.3390/ijms23095276] [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: 04/23/2022] [Revised: 05/04/2022] [Accepted: 05/06/2022] [Indexed: 11/17/2022] Open
Abstract
Xyloglucan is closely associated with cellulose and still retained with some modification in pretreated lignocellulose; however, its influence on lignocellulose biodegradation is less understood. TtGH74 from Thielavia terrestris displayed much higher catalytic activity than previously characterized fungal GH74 xyloglucanases. The carbohydrate-binding module 1 (CBM1) deleted variant (TtGH74ΔCBM) had the same optimum temperature and pH but an elevated thermostability. TtGH74 displayed a high binding affinity on xyloglucan and cellulose, while TtGH74ΔCBM completely lost the adsorption capability on cellulose. Their hydrolysis action alone or in combination with other glycoside hydrolases on the free xyloglucan, xyloglucan-coated phosphoric acid-swollen cellulose or pretreated corn bran and apple pomace was compared. CBM1 might not be essential for the hydrolysis of free xyloglucan but still effective for the associated xyloglucan to an extent. TtGH74 alone or synergistically acting with the CBH1/EG1 mixture was more effective in the hydrolysis of xyloglucan in corn bran, while TtGH74ΔCBM showed relatively higher catalytic activity on apple pomace, indicating that the role and significance of CBM1 are substrate-specific. The degrees of synergy for TtGH74 or TtGH74ΔCBM with the CBH1/EG1 mixture reached 1.22–2.02. The addition of GH10 xylanase in TtGH74 or the TtGH74ΔCBM/CBH1/EG1 mixture further improved the overall hydrolysis efficiency, and the degrees of synergy were up to 1.50–2.16.
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Sun P, Li X, Dilokpimol A, Henrissat B, de Vries RP, Kabel MA, Mäkelä MR. Fungal glycoside hydrolase family 44 xyloglucanases are restricted to the phylum Basidiomycota and show a distinct xyloglucan cleavage pattern. iScience 2022; 25:103666. [PMID: 35028537 PMCID: PMC8741620 DOI: 10.1016/j.isci.2021.103666] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Revised: 11/23/2021] [Accepted: 12/16/2021] [Indexed: 11/26/2022] Open
Abstract
Xyloglucan is a prominent matrix heteropolysaccharide binding to cellulose microfibrils in primary plant cell walls. Hence, the hydrolysis of xyloglucan facilitates the overall lignocellulosic biomass degradation. Xyloglucanases (XEGs) are key enzymes classified in several glycoside hydrolase (GH) families. So far, family GH44 has been shown to contain bacterial XEGs only. Detailed genome analysis revealed GH44 members in fungal species from the phylum Basidiomycota, but not in other fungi, which we hypothesized to also be XEGs. Two GH44 enzymes from Dichomitus squalens and Pleurotus ostreatus were heterologously produced and characterized. They exhibited XEG activity and displayed a hydrolytic cleavage pattern different from that observed in fungal XEGs from other GH families. Specifically, the fungal GH44 XEGs were not hindered by substitution of neighboring glucosyl units and generated various "XXXG-type," "GXXX(G)-type," and "XXX-type" oligosaccharides. Overall, these fungal GH44 XEGs represent a novel class of enzymes for plant biomass conversion and valorization.
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Affiliation(s)
- Peicheng Sun
- Laboratory of Food Chemistry, Wageningen University and Research, Bornse Weilanden 9, 6708 WG Wageningen, the Netherlands
| | - Xinxin Li
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute and Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, the Netherlands
| | - Adiphol Dilokpimol
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute and Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, the Netherlands
| | - Bernard Henrissat
- DTU Bioengineering, Technical University of Denmark, Søltofts Plads, 2800 Kongens Lyngby, Denmark.,Department of Biological Sciences, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Ronald P de Vries
- Fungal Physiology, Westerdijk Fungal Biodiversity Institute and Fungal Molecular Physiology, Utrecht University, Uppsalalaan 8, 3584 CT Utrecht, the Netherlands
| | - Mirjam A Kabel
- Laboratory of Food Chemistry, Wageningen University and Research, Bornse Weilanden 9, 6708 WG Wageningen, the Netherlands
| | - Miia R Mäkelä
- Department of Microbiology, University of Helsinki, Viikinkaari 9, 00790 Helsinki, Finland
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Dautt-Castro M, Jijón-Moreno S, Gómez-Hernández N, del Carmen González-López M, Hernández-Hernández EJ, Rosendo-Vargas MM, Rebolledo-Prudencio OG, Casas-Flores S. New Insights on the Duality of Trichoderma as a Phytopathogen Killer and a Plant Protector Based on an Integrated Multi-omics Perspective. Fungal Biol 2022. [DOI: 10.1007/978-3-030-91650-3_5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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11
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Characterization of an extracellular α-xylosidase involved in xyloglucan degradation in Aspergillus oryzae. Appl Microbiol Biotechnol 2021; 106:675-687. [PMID: 34971412 DOI: 10.1007/s00253-021-11744-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2021] [Revised: 12/08/2021] [Accepted: 12/12/2021] [Indexed: 10/19/2022]
Abstract
α-Xylosidases release the α-D-xylopyranosyl side chain from di- and oligosaccharides derived from xyloglucans and are involved in xyloglucan degradation. In this study, an extracellular α-xylosidase, named AxyB, is identified and characterized in Aspergillus oryzae. AxyB belongs to the glycoside hydrolase family 31 and releases D-xylose from isoprimeverose (α-D-xylopyranosyl-(1 → 6)-D-glucopyranose) and xyloglucan oligosaccharides. In the hydrolysis of xyloglucan oligosaccharides (XLLG, Glc4Xyl3Gal2 nonasaccharide; XLXG/XXLG, Glc4Xyl3Gal1 octasaccharide; and XXXG, Glc4Xyl3 heptasaccharide), AxyB releases one molecule of the xylopyranosyl side chain attached to the non-reducing end of the β-1,4-glucan main chain of these xyloglucan oligosaccharides to yield GLLG (Glc4Xyl2Gal2), GLXG/GXLG (Glc4Xyl2Gal1), and GXXG (Glc4Xyl2). A. oryzae has both extracellular and intracellular α-xylosidase, suggesting that xyloglucan oligosaccharides are degraded by a combination of isoprimeverose-producing oligoxyloglucan hydrolase and intracellular α-xylosidase and a combination of extracellular α-xylosidase and β-glucosidase(s) in A. oryzae. KEY POINTS: • An extracellular α-xylosidase, AxyB, is identified in Aspergillus oryzae. • AxyB releases the xylopyranosyl side chain from xyloglucan oligosaccharides. • Different sets of glycosidases degrade xyloglucan oligosaccharides in A. oryzae.
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Moreira EA, Persinoti GF, Menezes LR, Paixão DAA, Alvarez TM, Cairo JPLF, Squina FM, Costa-Leonardo AM, Rodrigues A, Sillam-Dussès D, Arab A. Complementary Contribution of Fungi and Bacteria to Lignocellulose Digestion in the Food Stored by a Neotropical Higher Termite. Front Ecol Evol 2021. [DOI: 10.3389/fevo.2021.632590] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Lignocellulose digestion in termites is achieved through the functional synergy between gut symbionts and host enzymes. However, some species have evolved additional associations with nest microorganisms that collaborate in the decomposition of plant biomass. In a previous study, we determined that plant material packed with feces inside the nests of Cornitermes cumulans (Syntermitinae) harbors a distinct microbial assemblage. These food nodules also showed a high hemicellulolytic activity, possibly acting as an external place for complementary lignocellulose digestion. In this study, we used a combination of ITS sequence analysis, metagenomics, and metatranscriptomics to investigate the presence and differential expression of genes coding for carbohydrate-active enzymes (CAZy) in the food nodules and the gut of workers and soldiers. Our results confirm that food nodules express a distinct set of CAZy genes suggesting that stored plant material is initially decomposed by enzymes that target the lignin and complex polysaccharides from fungi and bacteria before the passage through the gut, where it is further targeted by a complementary set of cellulases, xylanases, and esterases produced by the gut microbiota and the termite host. We also showed that the expression of CAZy transcripts associated to endoglucanases and xylanases was higher in the gut of termites than in the food nodules. An additional finding in this study was the presence of fungi in the termite gut that expressed CAZy genes. This study highlights the importance of externalization of digestion by nest microbes and provides new evidence of complementary digestion in the context of higher termite evolution.
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Enzymatic degradation of xyloglucans by Aspergillus species: a comparative view of this genus. Appl Microbiol Biotechnol 2021; 105:2701-2711. [PMID: 33760931 DOI: 10.1007/s00253-021-11236-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2021] [Revised: 02/25/2021] [Accepted: 03/14/2021] [Indexed: 10/21/2022]
Abstract
Aspergillus species are closely associated with humanity through fermentation, infectious disease, and mycotoxin contamination of food. Members of this genus produce various enzymes to degrade plant polysaccharides, including starch, cellulose, xylan, and xyloglucan. This review focus on the machinery of the xyloglucan degradation using glycoside hydrolases, such as xyloglucanases, isoprimeverose-producing oligoxyloglucan hydrolases, and α-xylosidases, in Aspergillus species. Some xyloglucan degradation-related glycoside hydrolases are well conserved in this genus; however, other enzymes are not. Cooperative actions of these glycoside hydrolases are crucial for xyloglucan degradation in Aspergillus species. KEY POINTS: •Xyloglucan degradation-related enzymes of Aspergillus species are reviewed. •Each Aspergillus species possesses a different set of glycoside hydrolases. •The machinery of xyloglucan degradation of A. oryzae is overviewed.
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