1
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Wang S, Robertz S, Seven M, Kraemer F, Kuhn BM, Liu L, Lunde C, Pauly M, Ramírez V. A large-scale forward genetic screen for maize mutants with altered lignocellulosic properties. FRONTIERS IN PLANT SCIENCE 2023; 14:1099009. [PMID: 36959947 PMCID: PMC10028098 DOI: 10.3389/fpls.2023.1099009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Accepted: 02/21/2023] [Indexed: 06/18/2023]
Abstract
The development of efficient pipelines for the bioconversion of grass lignocellulosic feedstocks is challenging due to the limited understanding of the molecular mechanisms controlling the synthesis, deposition, and degradation of the varying polymers unique to grass cell walls. Here, we describe a large-scale forward genetic approach resulting in the identification of a collection of chemically mutagenized maize mutants with diverse alterations in their cell wall attributes such as crystalline cellulose content or hemicellulose composition. Saccharification yield, i.e. the amount of lignocellulosic glucose (Glc) released by means of enzymatic hydrolysis, is increased in two of the mutants and decreased in the remaining six. These mutants, termed candy-leaf (cal), show no obvious plant growth or developmental defects despite associated differences in their lignocellulosic composition. The identified cal mutants are a valuable tool not only to understand recalcitrance of grass lignocellulosics to enzymatic deconstruction but also to decipher grass-specific aspects of cell wall biology once the genetic basis, i.e. the location of the mutation, has been identified.
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Affiliation(s)
- Shaogan Wang
- Institute for Plant Cell Biology and Biotechnology-Cluster of Excellence on Plant Sciences, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Stefan Robertz
- Institute for Plant Cell Biology and Biotechnology-Cluster of Excellence on Plant Sciences, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Merve Seven
- Institute for Plant Cell Biology and Biotechnology-Cluster of Excellence on Plant Sciences, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | - Florian Kraemer
- Department of Plant and Microbial Biology, Energy Biosciences Institute, University of California, Berkeley, Berkeley, CA, United States
| | - Benjamin M. Kuhn
- Department of Plant and Microbial Biology, Energy Biosciences Institute, University of California, Berkeley, Berkeley, CA, United States
| | - Lifeng Liu
- Department of Plant and Microbial Biology, Energy Biosciences Institute, University of California, Berkeley, Berkeley, CA, United States
| | - China Lunde
- Plant Gene Expression Center, Agricultural Research Service, U.S. Department of Agriculture, Albany, CA, United States
| | - Markus Pauly
- Institute for Plant Cell Biology and Biotechnology-Cluster of Excellence on Plant Sciences, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
- Department of Plant and Microbial Biology, Energy Biosciences Institute, University of California, Berkeley, Berkeley, CA, United States
| | - Vicente Ramírez
- Institute for Plant Cell Biology and Biotechnology-Cluster of Excellence on Plant Sciences, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
- Department of Plant and Microbial Biology, Energy Biosciences Institute, University of California, Berkeley, Berkeley, CA, United States
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2
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Li H, Wang Y, Zhao P, Guo L, Huang L, Li X, Gao W. Naturally and chemically acetylated polysaccharides: Structural characteristics, synthesis, activities, and applications in the delivery system: A review. Carbohydr Polym 2023; 313:120746. [PMID: 37182931 DOI: 10.1016/j.carbpol.2023.120746] [Citation(s) in RCA: 18] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Revised: 02/22/2023] [Accepted: 02/22/2023] [Indexed: 03/03/2023]
Abstract
Acetylated polysaccharides refer to polysaccharides containing acetyl groups on sugar units. In the past, the acetylation modification of wall polysaccharides has been a hot research topic for scientists. However, in recent years, many studies have reported that acetylation-modified plant, animal, and microbial polysaccharide show great potential in delivery systems. From the latest perspective, this review systematically presents the different sources of naturally acetylated polysaccharides, the regularity of their modification, the chemical preparation of acetylation modifications, the biological activities and functions of acetylated polysaccharides, and the application in the delivery system. In nature, acetylated polysaccharides are extensively distributed in plants, microorganism, and animals. The level of acetylation modification, the distribution of chains, and the locations of acetylation modification sites differ between species. An increasing number of acetylated polysaccharides were prepared in the aqueous medium, which is safe, environment friendly, and low-cost. In addition to being necessary for plant growth and development, acetylated polysaccharides have immunomodulatory, antioxidant, and anticancer properties. The above-mentioned multiple sources, multifunctional and multi-active acetylated polysaccharides, make them an increasingly important part of delivery systems. We conclude by discussing the future directions for research and development and the potential uses for acetylated polysaccharides.
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3
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Lassfolk R, Pedrón M, Tejero T, Merino P, Wärnå J, Leino R. Acetyl Group Migration in Xylan and Glucan Model Compounds as Studied by Experimental and Computational Methods. J Org Chem 2022; 87:14544-14554. [PMID: 36251002 PMCID: PMC9639004 DOI: 10.1021/acs.joc.2c01956] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
It was recently demonstrated by us that acetyl groups in oligosaccharides can migrate not only within one saccharide unit but also between two different saccharide units. Kinetics of this phenomenon were previously investigated in both mannan model compounds and a naturally occurring polysaccharide. In addition to mannans, there are also several other naturally acetylated polysaccharides, such as xyloglucans and xylans. Both xyloglucans and xylans are some of the most common acetylated polysaccharides in nature, displaying important roles in the plant cells. Considering the various biological roles of natural polysaccharides, it could be hypothesized that the intramolecular migration of acetyl groups might also be associated with regulation of the biological activity of polysaccharides in nature. Consequently, a better understanding of the overall migration phenomenon across the glycosidic bonds could help to understand the potential role of such migrations in the context of the biological activity of polysaccharides. Here, we present a detailed investigation on acetyl group migration in the synthesized xylan and glucan trisaccharide model compounds by a combination of experimental and computational methods, showing that the migration between the saccharide units proceeds from a secondary hydroxyl group of one saccharide unit toward a primary hydroxyl group of the other unit.
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Affiliation(s)
- Robert Lassfolk
- Laboratory
of Molecular Science and Engineering, Åbo
Akademi University, 20500Turku, Finland
| | - Manuel Pedrón
- Institute
of Biocomputation & Physics of Complex Systems (BIFI), University of Zaragoza, 50009Zaragoza, Spain
| | - Tomás Tejero
- Institute
of Chemical Synthesis & Homogeneous Catalysis (ISQCH), University of Zaragoza, 50009Zaragoza, Spain
| | - Pedro Merino
- Institute
of Biocomputation & Physics of Complex Systems (BIFI), University of Zaragoza, 50009Zaragoza, Spain,
| | - Johan Wärnå
- Laboratory
of Industrial Chemistry and Reaction Engineering, Åbo Akademi University, 20500Turku, Finland
| | - Reko Leino
- Laboratory
of Molecular Science and Engineering, Åbo
Akademi University, 20500Turku, Finland,
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4
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Dilokpimol A, Verkerk B, Li X, Bellemare A, Lavallee M, Frommhagen M, Nørmølle Underlin E, Kabel MA, Powlowski J, Tsang A, de Vries RP. Screening of novel fungal Carbohydrate Esterase family 1 enzymes identifies three novel dual feruloyl/acetyl xylan esterases. FEBS Lett 2022; 596:1932-1943. [DOI: 10.1002/1873-3468.14322] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2021] [Revised: 02/09/2022] [Accepted: 02/10/2022] [Indexed: 11/06/2022]
Affiliation(s)
- Adiphol Dilokpimol
- Fungal Physiology Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology Utrecht University Uppsalalaan 8 3584 CT Utrecht The Netherlands
- Current address: Protein Production Team VTT Technical Research Center of Finland Ltd Tietotie 2 02150 Espoo Finland
| | - Bart Verkerk
- Fungal Physiology Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology Utrecht University Uppsalalaan 8 3584 CT Utrecht The Netherlands
| | - Xinxin Li
- Fungal Physiology Westerdijk Fungal Biodiversity Institute & Fungal Molecular Physiology Utrecht University Uppsalalaan 8 3584 CT Utrecht The Netherlands
| | - Annie Bellemare
- Centre for Functional and Structural Genomics Concordia University Sherbrooke St. W. Montreal QC H4B 1R6 Canada
| | - Mathieu Lavallee
- Centre for Functional and Structural Genomics Concordia University Sherbrooke St. W. Montreal QC H4B 1R6 Canada
| | - Matthias Frommhagen
- Laboratory of Food Chemistry Wageningen University and Research Bornse Weilanden 9 6708 WG Wageningen The Netherlands
| | - Emilie Nørmølle Underlin
- Laboratory of Food Chemistry Wageningen University and Research Bornse Weilanden 9 6708 WG Wageningen The Netherlands
- Department of Chemistry Technical University of Denmark Building 207 Kemitorvet DK‐2800 Denmark
| | - Mirjam A. Kabel
- Laboratory of Food Chemistry Wageningen University and Research Bornse Weilanden 9 6708 WG Wageningen The Netherlands
| | - Justin Powlowski
- Centre for Functional and Structural Genomics Concordia University Sherbrooke St. W. Montreal QC H4B 1R6 Canada
| | - Adrian Tsang
- Centre for Functional and Structural Genomics Concordia University Sherbrooke St. W. Montreal QC H4B 1R6 Canada
| | - 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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5
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Rodríguez ES, Díaz-Arenas GL, Makart S, Ghosh D, Patti AF, Garnier G, Tanner J, Paull B. Determination of xylooligosaccharides produced from enzymatic hydrolysis of beechwood xylan using high-performance anion-exchange chromatography tandem mass spectrometry. J Chromatogr A 2022; 1666:462836. [DOI: 10.1016/j.chroma.2022.462836] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Revised: 01/14/2022] [Accepted: 01/18/2022] [Indexed: 01/01/2023]
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6
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Lannuzel C, Smith A, Mary A, Della Pia E, Kabel M, de Vries S. Improving fiber utilization from rapeseed and sunflower seed meals to substitute soybean meal in pig and chicken diets: A review. Anim Feed Sci Technol 2022. [DOI: 10.1016/j.anifeedsci.2022.115213] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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7
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Liu H, Wei X, Zu S, Lin X, Zhang J, Shi A, Wang Q, He N. Separation and identification of neutral oligosaccharides with prebiotic activities from apple pectin. Food Hydrocoll 2021. [DOI: 10.1016/j.foodhyd.2021.107062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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8
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Lassfolk R, Bertuzzi S, Ardá A, Wärnå J, Jiménez‐Barbero J, Leino R. Kinetic Studies of Acetyl Group Migration between the Saccharide Units in an Oligomannoside Trisaccharide Model Compound and a Native Galactoglucomannan Polysaccharide. Chembiochem 2021; 22:2986-2995. [PMID: 34405515 PMCID: PMC8597014 DOI: 10.1002/cbic.202100374] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Indexed: 01/11/2023]
Abstract
Acyl group migration is a fundamental phenomenon in carbohydrate chemistry, recently shown to take place also between two non-adjacent hydroxyl groups, across the glycosidic bond, in a β-(1→4)-linked mannan trisaccharide model compound. With the central mannoside unit containing acetyl groups at the O2 and O3 positions, the O2-acetyl was in the earlier study shown to migrate to O6 of the reducing end. Potential implications of the general acyl migration process on cell signaling events and plant growth in nature are intriguing open questions. In the present work, migration kinetics in this original trisaccharide model system were studied in more detail together with potential interactions of the model compound and the migration products with DC-SIGN lectin. Furthermore, we demonstrate here for the first time that similar migration may also take place in native polysaccharides, here represented by galactoglucomannan from Norway spruce.
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Affiliation(s)
- Robert Lassfolk
- Laboratory of Molecular Science and EngineeringÅbo Akademi University20500TurkuFinland
| | - Sara Bertuzzi
- Chemical Glycobiology LaboratoryCIC bioGUNEBizkaia Technology Park, Building 80048160DerioSpain
| | - Ana Ardá
- Chemical Glycobiology LaboratoryCIC bioGUNEBizkaia Technology Park, Building 80048160DerioSpain
- Ikerbasque, Basque Foundation for SciencePlaza Euskadi 548009BilbaoSpain
| | - Johan Wärnå
- Laboratory of Industrial Chemistry and Reaction EngineeringÅbo Akademi University20500TurkuFinland
| | - Jesús Jiménez‐Barbero
- Chemical Glycobiology LaboratoryCIC bioGUNEBizkaia Technology Park, Building 80048160DerioSpain
- Ikerbasque, Basque Foundation for SciencePlaza Euskadi 548009BilbaoSpain
- Department of Organic & Inorganic ChemistryUniversity of the Basque Country, UPV/EHU48940LeioaBizkaiaSpain
| | - Reko Leino
- Laboratory of Molecular Science and EngineeringÅbo Akademi University20500TurkuFinland
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9
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Deralia PK, Jensen A, Felby C, Thygesen LG. Chemistry of lignin and hemicellulose structures interacts with hydrothermal pretreatment severity and affects cellulose conversion. Biotechnol Prog 2021; 37:e3189. [PMID: 34176230 DOI: 10.1002/btpr.3189] [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: 10/10/2020] [Revised: 06/06/2021] [Accepted: 06/23/2021] [Indexed: 11/09/2022]
Abstract
Understanding of how the plant cell walls of different plant species respond to pretreatment can help improve saccharification in bioconversion processes. Here, we studied the chemical and structural modifications in lignin and hemicellulose in hydrothermally pretreated poplar and wheat straw using wet chemistry and 2D heteronuclear single quantum coherence nuclear magnetic resonance (NMR) and their effects on cellulose conversion. Increased pretreatment severity reduced the levels of β─O─4 linkages with concomitant relatively increased levels of β─5 and β─β structures in the NMR spectra. β─5 structures appeared at medium and high severities for wheat straw while only β─β structures were observed at all pretreatment severities for poplar. These structural differences accounted for the differences in cellulose conversion for these biomasses at different severities. Changes in the hemicellulose component include a complete removal of arabinosyl and 4-O-methyl glucuronosyl substituents at low and medium pretreatment severities while acetyl groups were found to be relatively resistant toward hydrothermal pretreatment. This illustrates the importance of these groups, rather than xylan content, in the detrimental role of xylan in cellulose saccharification and helps explain the higher poplar recalcitrance compared to wheat straw. The results point toward the need for both enzyme preparation development and pretreatment technologies to target specific plant species.
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Affiliation(s)
- Parveen Kumar Deralia
- Department of Geosciences and Natural Resource Management, University of Copenhagen, Frederiksberg, Denmark
| | - Anders Jensen
- Department of Geosciences and Natural Resource Management, University of Copenhagen, Frederiksberg, Denmark
| | - Claus Felby
- Department of Geosciences and Natural Resource Management, University of Copenhagen, Frederiksberg, Denmark
| | - Lisbeth Garbrecht Thygesen
- Department of Geosciences and Natural Resource Management, University of Copenhagen, Frederiksberg, Denmark
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10
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Kmezik C, Mazurkewich S, Meents T, McKee LS, Idström A, Armeni M, Savolainen O, Brändén G, Larsbrink J. A polysaccharide utilization locus from the gut bacterium Dysgonomonas mossii encodes functionally distinct carbohydrate esterases. J Biol Chem 2021; 296:100500. [PMID: 33667545 PMCID: PMC8040265 DOI: 10.1016/j.jbc.2021.100500] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Revised: 01/27/2021] [Accepted: 03/01/2021] [Indexed: 02/06/2023] Open
Abstract
The gut microbiota plays a central role in human health by enzymatically degrading dietary fiber and concomitantly excreting short chain fatty acids that are associated with manifold health benefits. The polysaccharide xylan is abundant in dietary fiber but noncarbohydrate decorations hinder efficient cleavage by glycoside hydrolases (GHs) and need to be addressed by carbohydrate esterases (CEs). Enzymes from carbohydrate esterase families 1 and 6 (CE1 and 6) perform key roles in xylan degradation by removing feruloyl and acetate decorations, yet little is known about these enzyme families especially with regard to their diversity in activity. Bacteroidetes bacteria are dominant members of the microbiota and often encode their carbohydrate-active enzymes in multigene polysaccharide utilization loci (PULs). Here we present the characterization of three CEs found in a PUL encoded by the gut Bacteroidete Dysgonomonas mossii. We demonstrate that the CEs are functionally distinct, with one highly efficient CE6 acetyl esterase and two CE1 enzymes with feruloyl esterase activities. One multidomain CE1 enzyme contains two CE1 domains: an N-terminal domain feruloyl esterase, and a C-terminal domain with minimal activity on model substrates. We present the structure of the C-terminal CE1 domain with the carbohydrate-binding module that bridges the two CE1 domains, as well as a complex of the same protein fragment with methyl ferulate. The investment of D. mossii in producing multiple CEs suggests that improved accessibility of xylan for GHs and cleavage of covalent polysaccharide-polysaccharide and lignin-polysaccharide bonds are important enzyme activities in the gut environment.
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Affiliation(s)
- Cathleen Kmezik
- Division of Industrial Biotechnology, Department of Biology and Biological Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - Scott Mazurkewich
- Division of Industrial Biotechnology, Department of Biology and Biological Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - Tomke Meents
- Division of Industrial Biotechnology, Department of Biology and Biological Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - Lauren Sara McKee
- Division of Glycoscience, Department of Chemistry, Royal Institute of Technology (KTH), AlbaNova University Centre, Stockholm, Sweden; Wallenberg Wood Science Center, Stockholm, Sweden
| | - Alexander Idström
- Department of Chemistry and Chemical Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - Marina Armeni
- Chalmers Mass Spectrometry Infrastructure, Department of Biology and Biological Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - Otto Savolainen
- Chalmers Mass Spectrometry Infrastructure, Department of Biology and Biological Engineering, Chalmers University of Technology, Gothenburg, Sweden; Department of Clinical Nutrition, Institute of Public Health and Clinical Nutrition, University of Eastern Finland, Kuopio, Finland
| | - Gisela Brändén
- Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden
| | - Johan Larsbrink
- Division of Industrial Biotechnology, Department of Biology and Biological Engineering, Chalmers University of Technology, Gothenburg, Sweden; Wallenberg Wood Science Center, Stockholm, Sweden.
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11
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Raji O, Arnling Bååth J, Vuong TV, Larsbrink J, Olsson L, Master ER. The coordinated action of glucuronoyl esterase and α-glucuronidase promotes the disassembly of lignin-carbohydrate complexes. FEBS Lett 2021; 595:351-359. [PMID: 33277689 PMCID: PMC8044923 DOI: 10.1002/1873-3468.14019] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Revised: 11/24/2020] [Accepted: 11/25/2020] [Indexed: 12/19/2022]
Abstract
Glucuronoxylans represent a significant fraction of woody biomass, and its decomposition is complicated by the presence of lignin–carbohydrate complexes (LCCs). Herein, LCCs from birchwood were used to investigate the potential coordinated action of a glucuronoyl esterase (TtCE15A) and two α‐glucuronidases (SdeAgu115A and AxyAgu115A). When supplementing α‐glucuronidase with equimolar quantities of TtCE15A, total MeGlcpA released after 72 h by SdeAgu115A and AxyAgu115A increased from 52% to 67%, and 61% to 95%, respectively. Based on the combined TtCE15A and AxyAgu115A activities, ~ 34% of MeGlcpA in the extracted birchwood glucuronoxylan was occupied as LCCs. Notably, insoluble LCC fractions reduced soluble α‐glucuronidase concentrations by up to 70%, whereas reduction in soluble TtCE15A was less than 30%, indicating different tendencies to adsorb onto the LCC substrate.
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Affiliation(s)
- Olanrewaju Raji
- Department of Chemical Engineering and Applied Science, University of Toronto, ON, Canada
| | - Jenny Arnling Bååth
- Department of Biology and Biological Engineering, Wallenberg Wood Science Center, Chalmers University of Technology, Gothenburg, Sweden
| | - Thu V Vuong
- Department of Chemical Engineering and Applied Science, University of Toronto, ON, Canada
| | - Johan Larsbrink
- Department of Biology and Biological Engineering, Wallenberg Wood Science Center, Chalmers University of Technology, Gothenburg, Sweden
| | - Lisbeth Olsson
- Department of Biology and Biological Engineering, Wallenberg Wood Science Center, Chalmers University of Technology, Gothenburg, Sweden
| | - Emma R Master
- Department of Chemical Engineering and Applied Science, University of Toronto, ON, Canada.,Department of Bioproducts and Biosystems, Aalto University, Espoo, Finland
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12
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Hettikankanamalage AA, Lassfolk R, Ekholm FS, Leino R, Crich D. Mechanisms of Stereodirecting Participation and Ester Migration from Near and Far in Glycosylation and Related Reactions. Chem Rev 2020; 120:7104-7151. [PMID: 32627532 PMCID: PMC7429366 DOI: 10.1021/acs.chemrev.0c00243] [Citation(s) in RCA: 108] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
This review is the counterpart of a 2018 Chemical Reviews article (Adero, P. O.; Amarasekara, H.; Wen, P.; Bohé, L.; Crich, D. Chem. Rev. 2018, 118, 8242-8284) that examined the mechanisms of chemical glycosylation in the absence of stereodirecting participation. Attention is now turned to a critical review of the evidence in support of stereodirecting participation in glycosylation reactions by esters from either the vicinal or more remote positions. As participation by esters is often accompanied by ester migration, the mechanism(s) of migration are also reviewed. Esters are central to the entire review, which accordingly opens with an overview of their structure and their influence on the conformations of six-membered rings. Next the structure and relative energetics of dioxacarbeniun ions are covered with emphasis on the influence of ring size. The existing kinetic evidence for participation is then presented followed by an overview of the various intermediates either isolated or characterized spectroscopically. The evidence supporting participation from remote or distal positions is critically examined, and alternative hypotheses for the stereodirecting effect of such esters are presented. The mechanisms of ester migration are first examined from the perspective of glycosylation reactions and then more broadly in the context of partially acylated polyols.
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Affiliation(s)
- Asiri A. Hettikankanamalage
- Department of Pharmaceutical and Biomedical Sciences, University of Georgia, 250 West Green Street, Athens, GA 30602, USA
- Department of Chemistry, University of Georgia, 140 Cedar Street, Athens, GA 30602, USA
| | - Robert Lassfolk
- Johan Gadolin Process Chemistry Centre, Laboratory of Molecular Science and Technology, Åbo Akademi University, 20500 Åbo, Finland
| | - Filip S. Ekholm
- Department of Chemistry, University of Helsinki, A. I. Virtasen aukio 1, 00014 Helsinki, Finland
| | - Reko Leino
- Johan Gadolin Process Chemistry Centre, Laboratory of Molecular Science and Technology, Åbo Akademi University, 20500 Åbo, Finland
| | - David Crich
- Department of Pharmaceutical and Biomedical Sciences, University of Georgia, 250 West Green Street, Athens, GA 30602, USA
- Department of Chemistry, University of Georgia, 140 Cedar Street, Athens, GA 30602, USA
- Complex Carbohydrate Research Center, University of Georgia, 315 Riverbend Road, Athens, GA 30602, USA
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13
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Wang Z, Pawar PMA, Derba-Maceluch M, Hedenström M, Chong SL, Tenkanen M, Jönsson LJ, Mellerowicz EJ. Hybrid Aspen Expressing a Carbohydrate Esterase Family 5 Acetyl Xylan Esterase Under Control of a Wood-Specific Promoter Shows Improved Saccharification. FRONTIERS IN PLANT SCIENCE 2020; 11:380. [PMID: 32322259 PMCID: PMC7156598 DOI: 10.3389/fpls.2020.00380] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Accepted: 03/17/2020] [Indexed: 05/12/2023]
Abstract
Fast-growing broad-leaf tree species can serve as feedstocks for production of bio-based chemicals and fuels through biochemical conversion of wood to monosaccharides. This conversion is hampered by the xylan acetylation pattern. To reduce xylan acetylation in the wood, the Hypocrea jecorina acetyl xylan esterase (HjAXE) from carbohydrate esterase (CE) family 5 was expressed in hybrid aspen under the control of the wood-specific PtGT43B promoter and targeted to the secretory pathway. The enzyme was predicted to deacetylate polymeric xylan in the vicinity of cellulose due to the presence of a cellulose-binding module. Cell-wall-bound protein fractions from developing wood of transgenic plants were capable of releasing acetyl from finely ground wood powder, indicative of active AXE present in cell walls of these plants, whereas no such activity was detected in wild-type plants. The transgenic lines grew in height and diameter as well as wild-type trees, whereas their internodes were slightly shorter, indicating higher leaf production. The average acetyl content in the wood of these lines was reduced by 13%, mainly due to reductions in di-acetylated xylose units, and in C-2 and C-3 mono-acetylated xylose units. Analysis of soluble cell wall polysaccharides revealed a 4% reduction in the fraction of xylose units and an 18% increase in the fraction of glucose units, whereas the contents of cellulose and lignin were not affected. Enzymatic saccharification of wood from transgenic plants resulted in 27% higher glucose yield than for wild-type plants. Brunauer-Emmett-Teller (BET) analysis and Simons' staining pointed toward larger surface area and improved cellulose accessibility for wood from transgenic plants compared to wood from wild-type plants, which could be achieved by HjAXE deacetylating xylan bound to cellulose. The results show that CE5 family can serve as a source of enzymes for in planta reduction of recalcitrance to saccharification.
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Affiliation(s)
- Zhao Wang
- Department of Chemistry, KBC Chemical-Biological Centre, Umeå University, Umeå, Sweden
| | | | - Marta Derba-Maceluch
- Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, Umeå, Sweden
| | - Mattias Hedenström
- Department of Chemistry, KBC Chemical-Biological Centre, Umeå University, Umeå, Sweden
| | - Sun-Li Chong
- Department of Food and Environmental Sciences, University of Helsinki, Helsinki, Finland
| | - Maija Tenkanen
- Department of Food and Environmental Sciences, University of Helsinki, Helsinki, Finland
| | - Leif J. Jönsson
- Department of Chemistry, KBC Chemical-Biological Centre, Umeå University, Umeå, Sweden
| | - Ewa J. Mellerowicz
- Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences, Umeå, Sweden
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14
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A pair of esterases from a commensal gut bacterium remove acetylations from all positions on complex β-mannans. Proc Natl Acad Sci U S A 2020; 117:7122-7130. [PMID: 32170022 DOI: 10.1073/pnas.1915376117] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
β-mannans and xylans are important components of the plant cell wall and they are acetylated to be protected from degradation by glycoside hydrolases. β-mannans are widely present in human and animal diets as fiber from leguminous plants and as thickeners and stabilizers in processed foods. There are many fully characterized acetylxylan esterases (AcXEs); however, the enzymes deacetylating mannans are less understood. Here we present two carbohydrate esterases, RiCE2 and RiCE17, from the Firmicute Roseburia intestinalis, which together deacetylate complex galactoglucomannan (GGM). The three-dimensional (3D) structure of RiCE17 with a mannopentaose in the active site shows that the CBM35 domain of RiCE17 forms a confined complex, where the axially oriented C2-hydroxyl of a mannose residue points toward the Ser41 of the catalytic triad. Cavities on the RiCE17 surface may accept galactosylations at the C6 positions of mannose adjacent to the mannose residue being deacetylated (subsite -1 and +1). In-depth characterization of the two enzymes using time-resolved NMR, high-performance liquid chromatography (HPLC), and mass spectrometry demonstrates that they work in a complementary manner. RiCE17 exclusively removes the axially oriented 2-O-acetylations on any mannose residue in an oligosaccharide, including double acetylated mannoses, while the RiCE2 is active on 3-O-, 4-O-, and 6-O-acetylations. Activity of RiCE2 is dependent on RiCE17 removing 2-O-acetylations from double acetylated mannose. Furthermore, transacetylation of oligosaccharides with the 2-O-specific RiCE17 provided insight into how temperature and pH affects acetyl migration on manno-oligosaccharides.
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Kmezik C, Bonzom C, Olsson L, Mazurkewich S, Larsbrink J. Multimodular fused acetyl-feruloyl esterases from soil and gut Bacteroidetes improve xylanase depolymerization of recalcitrant biomass. BIOTECHNOLOGY FOR BIOFUELS 2020; 13:60. [PMID: 32266006 PMCID: PMC7110780 DOI: 10.1186/s13068-020-01698-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Accepted: 03/16/2020] [Indexed: 05/04/2023]
Abstract
BACKGROUND Plant biomass is an abundant and renewable carbon source that is recalcitrant towards both chemical and biochemical degradation. Xylan is the second most abundant polysaccharide in biomass after cellulose, and it possesses a variety of carbohydrate substitutions and non-carbohydrate decorations which can impede enzymatic degradation by glycoside hydrolases. Carbohydrate esterases are able to cleave the ester-linked decorations and thereby improve the accessibility of the xylan backbone to glycoside hydrolases, thus improving the degradation process. Enzymes comprising multiple catalytic glycoside hydrolase domains on the same polypeptide have previously been shown to exhibit intramolecular synergism during degradation of biomass. Similarly, natively fused carbohydrate esterase domains are encoded by certain bacteria, but whether these enzymes can result in similar synergistic boosts in biomass degradation has not previously been evaluated. RESULTS Two carbohydrate esterases with similar architectures, each comprising two distinct physically linked catalytic domains from families 1 (CE1) and 6 (CE6), were selected from xylan-targeting polysaccharide utilization loci (PULs) encoded by the Bacteroidetes species Bacteroides ovatus and Flavobacterium johnsoniae. The full-length enzymes as well as the individual catalytic domains showed activity on a range of synthetic model substrates, corn cob biomass, and Japanese beechwood biomass, with predominant acetyl esterase activity for the N-terminal CE6 domains and feruloyl esterase activity for the C-terminal CE1 domains. Moreover, several of the enzyme constructs were able to substantially boost the performance of a commercially available xylanase on corn cob biomass (close to twofold) and Japanese beechwood biomass (up to 20-fold). Interestingly, a significant improvement in xylanase biomass degradation was observed following addition of the full-length multidomain enzyme from B. ovatus versus the addition of its two separated single domains, indicating an intramolecular synergy between the esterase domains. Despite high sequence similarities between the esterase domains from B. ovatus and F. johnsoniae, their addition to the xylanolytic reaction led to different degradation patterns. CONCLUSION We demonstrated that multidomain carbohydrate esterases, targeting the non-carbohydrate decorations on different xylan polysaccharides, can considerably facilitate glycoside hydrolase-mediated hydrolysis of xylan and xylan-rich biomass. Moreover, we demonstrated for the first time a synergistic effect between the two fused catalytic domains of a multidomain carbohydrate esterase.
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Affiliation(s)
- Cathleen Kmezik
- Division of Industrial Biotechnology, Department of Biology and Biological Engineering, Chalmers University of Technology, 412 96 Gothenburg, Sweden
| | - Cyrielle Bonzom
- Division of Industrial Biotechnology, Department of Biology and Biological Engineering, Chalmers University of Technology, 412 96 Gothenburg, Sweden
| | - Lisbeth Olsson
- Division of Industrial Biotechnology, Department of Biology and Biological Engineering, Chalmers University of Technology, 412 96 Gothenburg, Sweden
- Wallenberg Wood Science Center, Chalmers University of Technology, 412 96 Gothenburg, Sweden
| | - Scott Mazurkewich
- Division of Industrial Biotechnology, Department of Biology and Biological Engineering, Chalmers University of Technology, 412 96 Gothenburg, Sweden
- Wallenberg Wood Science Center, Chalmers University of Technology, 412 96 Gothenburg, Sweden
| | - Johan Larsbrink
- Division of Industrial Biotechnology, Department of Biology and Biological Engineering, Chalmers University of Technology, 412 96 Gothenburg, Sweden
- Wallenberg Wood Science Center, Chalmers University of Technology, 412 96 Gothenburg, Sweden
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Glucuronoarabinoxylans and other cell wall polysaccharides from shoots of Guadua chacoensis obtained by extraction in different conditions. Carbohydr Polym 2019; 226:115313. [DOI: 10.1016/j.carbpol.2019.115313] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Revised: 09/06/2019] [Accepted: 09/09/2019] [Indexed: 12/25/2022]
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Lassfolk R, Rahkila J, Johansson MP, Ekholm FS, Wärnå J, Leino R. Acetyl Group Migration across the Saccharide Units in Oligomannoside Model Compound. J Am Chem Soc 2019; 141:1646-1654. [PMID: 30586298 DOI: 10.1021/jacs.8b11563] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Acetylated oligosaccharides are common in nature. While they are involved in several biochemical and biological processes, the role of the acetyl groups and the complexity of their migration has largely gone unnoticed. In this work, by combination of organic synthesis, NMR spectroscopy and quantum chemical modeling, we show that acetyl group migration is a much more complex phenomenon than previously known. By use of synthetic oligomannoside model compounds, we demonstrate, for the first time, that the migration of acetyl groups in oligosaccharides and polysaccharides may not be limited to transfer within a single monosaccharide moiety, but may also involve migration over a glycosidic bond between two different saccharide units. The observed phenomenon is not only interesting from the chemical point of view, but it also raises new questions about the potential biological role of acylated carbohydrates in nature.
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Affiliation(s)
- Robert Lassfolk
- Johan Gadolin Process Chemistry Centre, Laboratory of Organic Chemistry, Åbo Akademi University , FI-20500 Åbo , Finland
| | - Jani Rahkila
- Johan Gadolin Process Chemistry Centre, Laboratory of Organic Chemistry, Åbo Akademi University , FI-20500 Åbo , Finland
| | - Mikael P Johansson
- Department of Chemistry , University of Helsinki , FI-00014 Helsinki , Finland.,Helsinki Institute of Sustainability Science, HELSUS , FI-00014 Helsinki , Finland
| | - Filip S Ekholm
- Department of Chemistry , University of Helsinki , FI-00014 Helsinki , Finland
| | - Johan Wärnå
- Johan Gadolin Process Chemistry Centre, Laboratory of Industrial Chemistry and Reaction Engineering, Åbo Akademi University , FI-20500 Åbo , Finland
| | - Reko Leino
- Johan Gadolin Process Chemistry Centre, Laboratory of Organic Chemistry, Åbo Akademi University , FI-20500 Åbo , Finland
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NMR and ESI–MS spectrometry characterization of autohydrolysis xylo-oligosaccharides separated by gel permeation chromatography. Carbohydr Polym 2018; 195:303-310. [DOI: 10.1016/j.carbpol.2018.04.088] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2018] [Revised: 03/29/2018] [Accepted: 04/23/2018] [Indexed: 11/23/2022]
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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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Pauly M, Ramírez V. New Insights Into Wall Polysaccharide O-Acetylation. FRONTIERS IN PLANT SCIENCE 2018; 9:1210. [PMID: 30186297 PMCID: PMC6110886 DOI: 10.3389/fpls.2018.01210] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Accepted: 07/27/2018] [Indexed: 05/19/2023]
Abstract
The extracellular matrix of plants, algae, bacteria, fungi, and some archaea consist of a semipermeable composite containing polysaccharides. Many of these polysaccharides are O-acetylated imparting important physiochemical properties to the polymers. The position and degree of O-acetylation is genetically determined and varies between organisms, cell types, and developmental stages. Despite the importance of wall polysaccharide O-acetylation, only recently progress has been made to elucidate the molecular mechanism of O-acetylation. In plants, three protein families are involved in the transfer of the acetyl substituents to the various polysaccharides. In other organisms, this mechanism seems to be conserved, although the number of required components varies. In this review, we provide an update on the latest advances on plant polysaccharide O-acetylation and related information from other wall polysaccharide O-acetylating organisms such as bacteria and fungi. The biotechnological impact of understanding wall polysaccharide O-acetylation ranges from the design of novel drugs against human pathogenic bacteria to the development of improved lignocellulosic feedstocks for biofuel production.
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Affiliation(s)
| | - Vicente Ramírez
- Institute for Plant Cell Biology and Biotechnology – Cluster of Excellence on Plant Sciences, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
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21
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Razeq FM, Jurak E, Stogios PJ, Yan R, Tenkanen M, Kabel MA, Wang W, Master ER. A novel acetyl xylan esterase enabling complete deacetylation of substituted xylans. BIOTECHNOLOGY FOR BIOFUELS 2018; 11:74. [PMID: 29588659 PMCID: PMC5863359 DOI: 10.1186/s13068-018-1074-3] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2017] [Accepted: 03/09/2018] [Indexed: 05/02/2023]
Abstract
BACKGROUND Acetylated 4-O-(methyl)glucuronoxylan (GX) is the main hemicellulose in deciduous hardwood, and comprises a β-(1→4)-linked xylopyranosyl (Xylp) backbone substituted by both acetyl groups and α-(1→2)-linked 4-O-methylglucopyranosyluronic acid (MeGlcpA). Whereas enzymes that target singly acetylated Xylp or doubly 2,3-O-acetyl-Xylp have been well characterized, those targeting (2-O-MeGlcpA)3-O-acetyl-Xylp structures in glucuronoxylan have remained elusive. RESULTS An unclassified carbohydrate esterase (FjoAcXE) was identified as a protein of unknown function from a polysaccharide utilization locus (PUL) otherwise comprising carbohydrate-active enzyme families known to target xylan. FjoAcXE was shown to efficiently release acetyl groups from internal (2-O-MeGlcpA)3-O-acetyl-Xylp structures, an activity that has been sought after but lacking in known carbohydrate esterases. FjoAcXE action boosted the activity of α-glucuronidases from families GH67 and GH115 by five and nine times, respectively. Moreover, FjoAcXE activity was not only restricted to GX, but also deacetylated (3-O-Araf)2-O-acetyl-Xylp of feruloylated xylooligomers, confirming the broad substrate range of this new carbohydrate esterase. CONCLUSION This study reports the discovery and characterization of the novel carbohydrate esterase, FjoAcXE. In addition to cleaving singly acetylated Xylp, and doubly 2,3-O-acetyl-Xylp, FjoAcXE efficiently cleaves internal 3-O-acetyl-Xylp linkages in (2-O-MeGlcpA)3-O-acetyl-Xylp residues along with densely substituted and branched xylooligomers; activities that until now were missing from the arsenal of enzymes required for xylan conversion.
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Affiliation(s)
- Fakhria M. Razeq
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, 200 College Street, Toronto, ON M5S 3E5 Canada
| | - Edita Jurak
- Department of Bioproducts and Biosystems, Aalto University, Kemistintie 1, 00076 Aalto Espoo, Finland
| | - Peter J. Stogios
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, 200 College Street, Toronto, ON M5S 3E5 Canada
| | - Ruoyu Yan
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, 200 College Street, Toronto, ON M5S 3E5 Canada
| | - Maija Tenkanen
- Department of Food and Environmental Sciences, University of Helsinki, P.O. Box 66, 00014 Helsinki, Finland
| | - Mirjam A. Kabel
- Laboratory of Food Chemistry, Wageningen University, Bornse Weilanden 9, 6708 WG Wageningen, The Netherlands
| | - Weijun Wang
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, 200 College Street, Toronto, ON M5S 3E5 Canada
| | - Emma R. Master
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, 200 College Street, Toronto, ON M5S 3E5 Canada
- Department of Bioproducts and Biosystems, Aalto University, Kemistintie 1, 00076 Aalto Espoo, Finland
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22
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Perera N, Yang FL, Chern J, Chiu HW, Hsieh CY, Li LH, Zhang YL, Hua KF, Wu SH. Carboxylic and O-acetyl moieties are essential for the immunostimulatory activity of glucuronoxylomannan: a novel TLR4 specific immunostimulator from Auricularia auricula-judae. Chem Commun (Camb) 2018; 54:6995-6998. [DOI: 10.1039/c7cc09927d] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
O-acetyl and carboxylic functionalities of Auricularia auricula-judae glucuronoxylomannan play critical roles in TLR4/MD2 receptor binding for its immunostimulatory activity.
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Affiliation(s)
- Namal Perera
- Institute of Biological Chemistry
- Academia Sinica
- Taipei
- Taiwan
- Chemical Biology and Molecular Biophysics Program
| | - Feng-Ling Yang
- Institute of Biological Chemistry
- Academia Sinica
- Taipei
- Taiwan
| | - Jeffy Chern
- Institute of Biological Chemistry
- Academia Sinica
- Taipei
- Taiwan
- Chemical Biology and Molecular Biophysics Program
| | - Hsiao-Wen Chiu
- Graduate Institute of Life Sciences
- National Defense Medical Center
- Taipei
- Taiwan
- Department of Biotechnology and Animal Science
| | - Chih-Yu Hsieh
- Department of Biotechnology and Animal Science
- National Ilan University
- Ilan
- Taiwan
| | - Lan-Hui Li
- Department of Laboratory Medicine, Linsen
- Chinese Medicine and Kunming Branch
- Taipei City Hospital
- Taipei
- Taiwan
| | - Yan-Long Zhang
- Key Laboratory of Molecular Biology of Heilongjiang Province
- College of Life Sciences
- Heilongjiang University
- Harbin 150080
- China
| | - Kuo-Feng Hua
- Department of Biotechnology and Animal Science
- National Ilan University
- Ilan
- Taiwan
- Department of Pathology
| | - Shih-Hsiung Wu
- Institute of Biological Chemistry
- Academia Sinica
- Taipei
- Taiwan
- Chemical Biology and Molecular Biophysics Program
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23
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Grantham NJ, Wurman-Rodrich J, Terrett OM, Lyczakowski JJ, Stott K, Iuga D, Simmons TJ, Durand-Tardif M, Brown SP, Dupree R, Busse-Wicher M, Dupree P. An even pattern of xylan substitution is critical for interaction with cellulose in plant cell walls. NATURE PLANTS 2017; 3:859-865. [PMID: 28993612 DOI: 10.1038/s41477-017-0030-8] [Citation(s) in RCA: 130] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Accepted: 09/13/2017] [Indexed: 05/18/2023]
Abstract
Xylan and cellulose are abundant polysaccharides in vascular plants and essential for secondary cell wall strength. Acetate or glucuronic acid decorations are exclusively found on even-numbered residues in most of the glucuronoxylan polymer. It has been proposed that this even-specific positioning of the decorations might permit docking of xylan onto the hydrophilic face of a cellulose microfibril 1-3 . Consequently, xylan adopts a flattened ribbon-like twofold screw conformation when bound to cellulose in the cell wall 4 . Here we show that ESKIMO1/XOAT1/TBL29, a xylan-specific O-acetyltransferase, is necessary for generation of the even pattern of acetyl esters on xylan in Arabidopsis. The reduced acetylation in the esk1 mutant deregulates the position-specific activity of the xylan glucuronosyltransferase GUX1, and so the even pattern of glucuronic acid on the xylan is lost. Solid-state NMR of intact cell walls shows that, without the even-patterned xylan decorations, xylan does not interact normally with cellulose fibrils. We conclude that the even pattern of xylan substitutions seen across vascular plants enables the interaction of xylan with hydrophilic faces of cellulose fibrils, and is essential for development of normal plant secondary cell walls.
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Affiliation(s)
- Nicholas J Grantham
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QW, UK
| | - Joel Wurman-Rodrich
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QW, UK
| | - Oliver M Terrett
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QW, UK
| | - Jan J Lyczakowski
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QW, UK
| | - Katherine Stott
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QW, UK
| | - Dinu Iuga
- Department of Physics, University of Warwick, Coventry, CV4 7AL, UK
| | - Thomas J Simmons
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QW, UK
| | - Mylene Durand-Tardif
- Institut Jean-Pierre Bourgin, UMR 1318, INRA AgroParisTech CNRS, Université Paris-Saclay, 78026, Versailles Cedex, France
| | - Steven P Brown
- Department of Physics, University of Warwick, Coventry, CV4 7AL, UK
| | - Ray Dupree
- Department of Physics, University of Warwick, Coventry, CV4 7AL, UK
| | - Marta Busse-Wicher
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QW, UK
| | - Paul Dupree
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QW, UK.
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Smith PJ, Wang HT, York WS, Peña MJ, Urbanowicz BR. Designer biomass for next-generation biorefineries: leveraging recent insights into xylan structure and biosynthesis. BIOTECHNOLOGY FOR BIOFUELS 2017; 10:286. [PMID: 29213325 PMCID: PMC5708106 DOI: 10.1186/s13068-017-0973-z] [Citation(s) in RCA: 64] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Accepted: 11/20/2017] [Indexed: 05/02/2023]
Abstract
Xylans are the most abundant noncellulosic polysaccharides in lignified secondary cell walls of woody dicots and in both primary and secondary cell walls of grasses. These polysaccharides, which comprise 20-35% of terrestrial biomass, present major challenges for the efficient microbial bioconversion of lignocellulosic feedstocks to fuels and other value-added products. Xylans play a significant role in the recalcitrance of biomass to degradation, and their bioconversion requires metabolic pathways that are distinct from those used to metabolize cellulose. In this review, we discuss the key differences in the structural features of xylans across diverse plant species, how these features affect their interactions with cellulose and lignin, and recent developments in understanding their biosynthesis. In particular, we focus on how the combined structural and biosynthetic knowledge can be used as a basis for biomass engineering aimed at developing crops that are better suited as feedstocks for the bioconversion industry.
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Affiliation(s)
- Peter J. Smith
- Complex Carbohydrate Research Center, University of Georgia, 315 Riverbend Road, Athens, GA USA
- BioEnergy Science Center, Oak Ridge National Lab Laboratory, Oak Ridge, TN USA
| | - Hsin-Tzu Wang
- Complex Carbohydrate Research Center, University of Georgia, 315 Riverbend Road, Athens, GA USA
- BioEnergy Science Center, Oak Ridge National Lab Laboratory, Oak Ridge, TN USA
| | - William S. York
- Complex Carbohydrate Research Center, University of Georgia, 315 Riverbend Road, Athens, GA USA
- BioEnergy Science Center, Oak Ridge National Lab Laboratory, Oak Ridge, TN USA
| | - Maria J. Peña
- Complex Carbohydrate Research Center, University of Georgia, 315 Riverbend Road, Athens, GA USA
- BioEnergy Science Center, Oak Ridge National Lab Laboratory, Oak Ridge, TN USA
| | - Breeanna R. Urbanowicz
- Complex Carbohydrate Research Center, University of Georgia, 315 Riverbend Road, Athens, GA USA
- BioEnergy Science Center, Oak Ridge National Lab Laboratory, Oak Ridge, TN USA
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Towards enzymatic breakdown of complex plant xylan structures: State of the art. Biotechnol Adv 2016; 34:1260-1274. [PMID: 27620948 DOI: 10.1016/j.biotechadv.2016.09.001] [Citation(s) in RCA: 169] [Impact Index Per Article: 21.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Revised: 09/02/2016] [Accepted: 09/07/2016] [Indexed: 02/07/2023]
Abstract
Significant progress over the past few years has been achieved in the enzymology of microbial degradation and saccharification of plant xylan, after cellulose being the most abundant natural renewable polysaccharide. Several new types of xylan depolymerizing and debranching enzymes have been described in microorganisms. Despite the increasing variety of known glycoside hydrolases and carbohydrate esterases, some xylan structures still appear quite recalcitrant. This review focuses on the mode of action of different types of depolymerizing endoxylanases and their cooperation with β-xylosidase and accessory enzymes in breakdown of complex highly branched xylan structures. Emphasis is placed on the enzymatic hydrolysis of alkali-extracted deesterified polysaccharide as well as acetylated xylan isolated from plant cell walls under non-alkaline conditions. It is also shown how the combination of selected endoxylanases and debranching enzymes can determine the nature of prebiotic xylooligosaccharides or lead to complete hydrolysis of the polysaccharide. The article also highlights the possibility for discovery of novel xylanolytic enzymes, construction of multifunctional chimeric enzymes and xylanosomes in parallel with increasing knowledge on the fine structure of the polysaccharide.
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Schendel RR, Puchbauer AK, Britscho N, Bunzel M. Feruloylated Wheat Bran Arabinoxylans: Isolation and Characterization of Acetylated andO–2-Monosubstituted Structures. Cereal Chem 2016. [DOI: 10.1094/cchem-12-15-0250-r] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- Rachel R. Schendel
- Karlsruhe Institute of Technology (KIT), Institute of Applied Biosciences, Department of Food Chemistry and Phytochemistry, Adenauerring 20A, 76131 Karlsruhe, Germany
| | - Ann-Katrin Puchbauer
- Karlsruhe Institute of Technology (KIT), Institute of Applied Biosciences, Department of Food Chemistry and Phytochemistry, Adenauerring 20A, 76131 Karlsruhe, Germany
| | - Natalie Britscho
- Karlsruhe Institute of Technology (KIT), Institute of Applied Biosciences, Department of Food Chemistry and Phytochemistry, Adenauerring 20A, 76131 Karlsruhe, Germany
| | - Mirko Bunzel
- Karlsruhe Institute of Technology (KIT), Institute of Applied Biosciences, Department of Food Chemistry and Phytochemistry, Adenauerring 20A, 76131 Karlsruhe, Germany
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Pauly M, Keegstra K. Biosynthesis of the Plant Cell Wall Matrix Polysaccharide Xyloglucan. ANNUAL REVIEW OF PLANT BIOLOGY 2016; 67:235-59. [PMID: 26927904 DOI: 10.1146/annurev-arplant-043015-112222] [Citation(s) in RCA: 130] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Xyloglucan (XyG) is a matrix polysaccharide that is present in the cell walls of all land plants. It consists of a β-1,4-linked glucan backbone that is further substituted with xylosyl residues. These xylosyl residues can be further substituted with other glycosyl and nonglycosyl substituents that vary depending on the plant family and specific tissue. Advances in plant mutant isolation and characterization, functional genomics, and DNA sequencing have led to the identification of nearly all transferases and synthases necessary to synthesize XyG. Thus, in terms of the molecular mechanisms of plant cell wall polysaccharide biosynthesis, XyG is the most well understood. However, much remains to be learned about the molecular mechanisms of polysaccharide assembly and the regulation of these processes. Knowledge of the XyG biosynthetic machinery allows the XyG structure to be tailored in planta to ascertain the functions of this polysaccharide and its substituents in plant growth and interactions with the environment.
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Affiliation(s)
- Markus Pauly
- Department of Plant Cell Biology and Biotechnology, Heinrich Heine University, 40225 Düsseldorf, Germany;
| | - Kenneth Keegstra
- DOE Great Lakes Bioenergy Research Center, DOE Plant Research Laboratory, and Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan 48824
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Xylan decoration patterns and the plant secondary cell wall molecular architecture. Biochem Soc Trans 2016; 44:74-8. [DOI: 10.1042/bst20150183] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The molecular architecture of plant secondary cell walls is still not resolved. There are several proposed structures for cellulose fibrils, the main component of plant cell walls and the conformation of other molecules is even less well known. Glucuronic acid (GlcA) substitution of xylan (GUX) enzymes, in CAZy family glycosyl transferase (GT)8, decorate the xylan backbone with various specific patterns of GlcA. It was recently discovered that dicot xylan has a domain with the side chain decorations distributed on every second unit of the backbone (xylose). If the xylan backbone folds in a similar way to glucan chains in cellulose (2-fold helix), this kind of arrangement may allow the undecorated side of the xylan chain to hydrogen bond with the hydrophilic surface of cellulose microfibrils. MD simulations suggest that such interactions are energetically stable. We discuss the possible role of this xylan decoration pattern in building of the plant cell wall.
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Mori T, Tsuboi Y, Ishida N, Nishikubo N, Demura T, Kikuchi J. Multidimensional High-Resolution Magic Angle Spinning and Solution-State NMR Characterization of (13)C-labeled Plant Metabolites and Lignocellulose. Sci Rep 2015; 5:11848. [PMID: 26143886 PMCID: PMC4491710 DOI: 10.1038/srep11848] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Accepted: 06/08/2015] [Indexed: 01/18/2023] Open
Abstract
Lignocellulose, which includes mainly cellulose, hemicellulose, and lignin, is a potential resource for the production of chemicals and for other applications. For effective production of materials derived from biomass, it is important to characterize the metabolites and polymeric components of the biomass. Nuclear magnetic resonance (NMR) spectroscopy has been used to identify biomass components; however, the NMR spectra of metabolites and lignocellulose components are ambiguously assigned in many cases due to overlapping chemical shift peaks. Using our 13C-labeling technique in higher plants such as poplar samples, we demonstrated that overlapping peaks could be resolved by three-dimensional NMR experiments to more accurately assign chemical shifts compared with two-dimensional NMR measurements. Metabolites of the 13C-poplar were measured by high-resolution magic angle spinning NMR spectroscopy, which allows sample analysis without solvent extraction, while lignocellulose components of the 13C-poplar dissolved in dimethylsulfoxide/pyridine solvent were analyzed by solution-state NMR techniques. Using these methods, we were able to unambiguously assign chemical shifts of small and macromolecular components in 13C-poplar samples. Furthermore, using samples of less than 5 mg, we could differentiate between two kinds of genes that were overexpressed in poplar samples, which produced clearly modified plant cell wall components.
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Affiliation(s)
- Tetsuya Mori
- 1] Graduate School of Bioagricultural Sciences, Nagoya University, 1 Furo-cho, Chikusa-ku, Nagoya 464-0810, Japan [2] Biotechnology Laboratory, Toyota Central R&D Labs, Inc., 41-1, Nagakute 480-1192, Japan
| | - Yuuri Tsuboi
- RIKEN Center for Sustainable Resource Science, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan
| | - Nobuhiro Ishida
- Biotechnology Laboratory, Toyota Central R&D Labs, Inc., 41-1, Nagakute 480-1192, Japan
| | - Nobuyuki Nishikubo
- RIKEN Center for Sustainable Resource Science, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan
| | - Taku Demura
- 1] RIKEN Center for Sustainable Resource Science, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan [2] Biomass Engineering Program, RIKEN Research Cluster for Innovation, 2-1 Hirosawa, Wako 351-0198, Japan
| | - Jun Kikuchi
- 1] Graduate School of Bioagricultural Sciences, Nagoya University, 1 Furo-cho, Chikusa-ku, Nagoya 464-0810, Japan [2] RIKEN Center for Sustainable Resource Science, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan [3] Biomass Engineering Program, RIKEN Research Cluster for Innovation, 2-1 Hirosawa, Wako 351-0198, Japan [4] Graduate School of Medical Life Science, Yokohama City University, 1-7-29 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan
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Structural Diversity and Function of Xyloglucan Sidechain Substituents. PLANTS 2014; 3:526-42. [PMID: 27135518 PMCID: PMC4844278 DOI: 10.3390/plants3040526] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/07/2014] [Revised: 11/03/2014] [Accepted: 11/04/2014] [Indexed: 12/02/2022]
Abstract
Xyloglucan (XyG) is a hemicellulose found in the cell walls of all land plants including early-divergent groups such as liverworts, hornworts and mosses. The basic structure of XyG, a xylosylated glucan, is similar in all of these plants but additional substituents can vary depending on plant family, tissue, and developmental stage. A comprehensive list of known XyG sidechain substituents is assembled including their occurrence within plant families, thereby providing insight into the evolutionary origin of the various sidechains. Recent advances in DNA sequencing have enabled comparative genomics approaches for the identification of XyG biosynthetic enzymes in Arabidopsis thaliana as well as in non-model plant species. Characterization of these biosynthetic genes not only allows the determination of their substrate specificity but also provides insights into the function of the various substituents in plant growth and development.
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Urbanowicz BR, Peña MJ, Moniz HA, Moremen KW, York WS. Two Arabidopsis proteins synthesize acetylated xylan in vitro. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2014; 80:197-206. [PMID: 25141999 PMCID: PMC4184958 DOI: 10.1111/tpj.12643] [Citation(s) in RCA: 148] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Revised: 07/18/2014] [Accepted: 08/01/2014] [Indexed: 05/17/2023]
Abstract
Xylan is the third most abundant glycopolymer on earth after cellulose and chitin. As a major component of wood, grain and forage, this natural biopolymer has far-reaching impacts on human life. This highly acetylated cell wall polysaccharide is a vital component of the plant cell wall, which functions as a molecular scaffold, providing plants with mechanical strength and flexibility. Mutations that impair synthesis of the xylan backbone give rise to plants that fail to grow normally because of collapsed xylem cells in the vascular system. Phenotypic analysis of these mutants has implicated many proteins in xylan biosynthesis; however, the enzymes directly responsible for elongation and acetylation of the xylan backbone have not been unambiguously identified. Here we provide direct biochemical evidence that two Arabidopsis thaliana proteins, IRREGULAR XYLEM 10-L (IRX10-L) and ESKIMO1/TRICOME BIREFRINGENCE 29 (ESK1/TBL29), catalyze these respective processes in vitro. By identifying the elusive xylan synthase and establishing ESK1/TBL29 as the archetypal plant polysaccharide O-acetyltransferase, we have resolved two long-standing questions in plant cell wall biochemistry. These findings shed light on integral steps in the molecular pathways used by plants to synthesize a major component of the world's biomass and expand our toolkit for producing glycopolymers with valuable properties.
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Affiliation(s)
- Breeanna R. Urbanowicz
- Complex Carbohydrate Research Center, University of Georgia, 315 Riverbend Road, Athens, GA 30602, USA
| | - Maria J. Peña
- Complex Carbohydrate Research Center, University of Georgia, 315 Riverbend Road, Athens, GA 30602, USA
- Corresponding authors: Maria J. Peña, Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30602, USA, +01 (706) 542-4419, William S. York, Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30602, USA, +01 (706) 542-4628 ,
| | - Heather A. Moniz
- Complex Carbohydrate Research Center, University of Georgia, 315 Riverbend Road, Athens, GA 30602, USA
| | - Kelley W. Moremen
- Complex Carbohydrate Research Center, University of Georgia, 315 Riverbend Road, Athens, GA 30602, USA
| | - William S. York
- Complex Carbohydrate Research Center, University of Georgia, 315 Riverbend Road, Athens, GA 30602, USA
- Corresponding authors: Maria J. Peña, Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30602, USA, +01 (706) 542-4419, William S. York, Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30602, USA, +01 (706) 542-4628 ,
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Sénéchal F, Wattier C, Rustérucci C, Pelloux J. Homogalacturonan-modifying enzymes: structure, expression, and roles in plants. JOURNAL OF EXPERIMENTAL BOTANY 2014; 65:5125-60. [PMID: 25056773 PMCID: PMC4400535 DOI: 10.1093/jxb/eru272] [Citation(s) in RCA: 155] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Revised: 05/20/2014] [Accepted: 05/22/2014] [Indexed: 05/18/2023]
Abstract
Understanding the changes affecting the plant cell wall is a key element in addressing its functional role in plant growth and in the response to stress. Pectins, which are the main constituents of the primary cell wall in dicot species, play a central role in the control of cellular adhesion and thereby of the rheological properties of the wall. This is likely to be a major determinant of plant growth. How the discrete changes in pectin structure are mediated is thus a key issue in our understanding of plant development and plant responses to changes in the environment. In particular, understanding the remodelling of homogalacturonan (HG), the most abundant pectic polymer, by specific enzymes is a current challenge in addressing its fundamental role. HG, a polymer that can be methylesterified or acetylated, can be modified by HGMEs (HG-modifying enzymes) which all belong to large multigenic families in all species sequenced to date. In particular, both the degrees of substitution (methylesterification and/or acetylation) and polymerization can be controlled by specific enzymes such as pectin methylesterases (PMEs), pectin acetylesterases (PAEs), polygalacturonases (PGs), or pectate lyases-like (PLLs). Major advances in the biochemical and functional characterization of these enzymes have been made over the last 10 years. This review aims to provide a comprehensive, up to date summary of the recent data concerning the structure, regulation, and function of these fascinating enzymes in plant development and in response to biotic stresses.
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Affiliation(s)
- Fabien Sénéchal
- EA3900 BIOPI Biologie des Plantes et Innovation, Université de Picardie Jules Verne, 33 Rue St Leu, F-80039 Amiens, France
| | - Christopher Wattier
- EA3900 BIOPI Biologie des Plantes et Innovation, Université de Picardie Jules Verne, 33 Rue St Leu, F-80039 Amiens, France
| | - Christine Rustérucci
- EA3900 BIOPI Biologie des Plantes et Innovation, Université de Picardie Jules Verne, 33 Rue St Leu, F-80039 Amiens, France
| | - Jérôme Pelloux
- EA3900 BIOPI Biologie des Plantes et Innovation, Université de Picardie Jules Verne, 33 Rue St Leu, F-80039 Amiens, France
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Wang T, Salazar A, Zabotina OA, Hong M. Structure and dynamics of Brachypodium primary cell wall polysaccharides from two-dimensional (13)C solid-state nuclear magnetic resonance spectroscopy. Biochemistry 2014; 53:2840-54. [PMID: 24720372 DOI: 10.1021/bi500231b] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
The polysaccharide structure and dynamics in the primary cell wall of the model grass Brachypodium distachyon are investigated for the first time using solid-state nuclear magnetic resonance (NMR). While both grass and non-grass cell walls contain cellulose as the main structural scaffold, the former contains xylan with arabinose and glucuronic acid substitutions as the main hemicellulose, with a small amount of xyloglucan (XyG) and pectins, while the latter contains XyG as the main hemicellulose and significant amounts of pectins. We labeled the Brachypodium cell wall with (13)C to allow two-dimensional (2D) (13)C correlation NMR experiments under magic-angle spinning. Well-resolved 2D spectra are obtained in which the (13)C signals of cellulose, glucuronoarabinoxylan (GAX), and other matrix polysaccharides can be assigned. The assigned (13)C chemical shifts indicate that there are a large number of arabinose and xylose linkages in the wall, and GAX is significantly branched at the developmental stage of 2 weeks. 2D (13)C-(13)C correlation spectra measured with long spin diffusion mixing times indicate that the branched GAX approaches cellulose microfibrils on the nanometer scale, contrary to the conventional model in which only unbranched GAX can bind cellulose. The GAX chains are highly dynamic, with average order parameters of ~0.4. Biexponential (13)C T1 and (1)H T1ρ relaxation indicates that there are two dynamically distinct domains in GAX: the more rigid domain may be responsible for cross-linking cellulose microfibrils, while the more mobile domain may fill the interfibrillar space. This dynamic heterogeneity is more pronounced than that of the non-grass hemicellulose, XyG, suggesting that GAX adopts the mixed characteristics of XyG and pectins. Moderate differences in cellulose rigidity are observed between the Brachypodium and Arabidopsis cell walls, suggesting different effects of the matrix polysaccharides on cellulose. These data provide the first molecular-level structural information about the three-dimensional organization of the polysaccharides in the grass primary wall.
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Affiliation(s)
- Tuo Wang
- Department of Chemistry and Ames Laboratory and ‡Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University , Ames, Iowa 50011, United States
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Koutaniemi S, van Gool MP, Juvonen M, Jokela J, Hinz SW, Schols HA, Tenkanen M. Distinct roles of carbohydrate esterase family CE16 acetyl esterases and polymer-acting acetyl xylan esterases in xylan deacetylation. J Biotechnol 2013; 168:684-92. [PMID: 24140638 DOI: 10.1016/j.jbiotec.2013.10.009] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2013] [Revised: 10/02/2013] [Accepted: 10/07/2013] [Indexed: 10/26/2022]
Abstract
Mass spectrometric analysis was used to compare the roles of two acetyl esterases (AE, carbohydrate esterase family CE16) and three acetyl xylan esterases (AXE, families CE1 and CE5) in deacetylation of natural substrates, neutral (linear) and 4-O-methyl glucuronic acid (MeGlcA) substituted xylooligosaccharides (XOS). AEs were similarly restricted in their action and apparently removed in most cases only one acetyl group from the non-reducing end of XOS, acting as exo-deacetylases. In contrast, AXEs completely deacetylated longer neutral XOS but had difficulties with the shorter ones. Complete deacetylation of neutral XOS was obtained after the combined action of AEs and AXEs. MeGlcA substituents partially restricted the action of both types of esterases and the remaining acidic XOS were mainly substituted with one MeGlcA and one acetyl group, supposedly on the same xylopyranosyl residue. These resisting structures were degraded to great extent only after inclusion of α-glucuronidase, which acted with the esterases in a synergistic manner. When used together with xylan backbone degrading endoxylanase and β-xylosidase, both AE and AXE enhanced the hydrolysis of complex XOS equally.
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Affiliation(s)
- S Koutaniemi
- Department of Food and Environmental Chemistry, University of Helsinki, P.O. Box 27, 00014 Helsinki, Finland.
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Efficient separation of oxidized cello-oligosaccharides generated by cellulose degrading lytic polysaccharide monooxygenases. J Chromatogr A 2013; 1271:144-52. [DOI: 10.1016/j.chroma.2012.11.048] [Citation(s) in RCA: 127] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2012] [Revised: 11/15/2012] [Accepted: 11/18/2012] [Indexed: 11/23/2022]
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Gille S, Pauly M. O-acetylation of plant cell wall polysaccharides. FRONTIERS IN PLANT SCIENCE 2012; 3:12. [PMID: 22639638 PMCID: PMC3355586 DOI: 10.3389/fpls.2012.00012] [Citation(s) in RCA: 147] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2011] [Accepted: 01/12/2012] [Indexed: 05/17/2023]
Abstract
Plant cell walls are composed of structurally diverse polymers, many of which are O-acetylated. How plants O-acetylate wall polymers and what its function is remained elusive until recently, when two protein families were identified in the model plant Arabidopsis that are involved in the O-acetylation of wall polysaccharides - the reduced wall acetylation (RWA) and the trichome birefringence-like (TBL) proteins. This review discusses the role of these two protein families in polysaccharide O-acetylation and outlines the differences and similarities of polymer acetylation mechanisms in plants, fungi, bacteria, and mammals. Members of the TBL protein family had been shown to impact pathogen resistance, freezing tolerance, and cellulose biosynthesis. The connection of TBLs to polysaccharide O-acetylation thus gives crucial leads into the biological function of wall polymer O-acetylation. From a biotechnological point understanding the O-acetylation mechanism is important as acetyl-substituents inhibit the enzymatic degradation of wall polymers and released acetate can be a potent inhibitor in microbial fermentations, thus impacting the economic viability of, e.g., lignocellulosic based biofuel production.
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Affiliation(s)
- Sascha Gille
- Energy Biosciences Institute, University of California BerkeleyBerkeley, CA, USA
| | - Markus Pauly
- Energy Biosciences Institute, University of California BerkeleyBerkeley, CA, USA
- *Correspondence: Markus Pauly, Calvin Lab, Energy Biosciences Institute, University of California Berkeley, Berkeley, CA 94720, USA. e-mail:
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Leijdekkers A, Sanders M, Schols H, Gruppen H. Characterizing plant cell wall derived oligosaccharides using hydrophilic interaction chromatography with mass spectrometry detection. J Chromatogr A 2011; 1218:9227-35. [DOI: 10.1016/j.chroma.2011.10.068] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2011] [Revised: 10/19/2011] [Accepted: 10/24/2011] [Indexed: 10/15/2022]
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Pouvreau L, Jonathan M, Kabel M, Hinz S, Gruppen H, Schols H. Characterization and mode of action of two acetyl xylan esterases from Chrysosporium lucknowense C1 active towards acetylated xylans. Enzyme Microb Technol 2011; 49:312-20. [DOI: 10.1016/j.enzmictec.2011.05.010] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2010] [Revised: 05/10/2011] [Accepted: 05/16/2011] [Indexed: 11/24/2022]
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Structural features and properties of soluble products derived from Eucalyptus globulus hemicelluloses. Food Chem 2011. [DOI: 10.1016/j.foodchem.2011.02.066] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Biochemical characterization and relative expression levels of multiple carbohydrate esterases of the xylanolytic rumen bacterium Prevotella ruminicola 23 grown on an ester-enriched substrate. Appl Environ Microbiol 2011; 77:5671-81. [PMID: 21742923 DOI: 10.1128/aem.05321-11] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We measured expression and used biochemical characterization of multiple carbohydrate esterases by the xylanolytic rumen bacterium Prevotella ruminicola 23 grown on an ester-enriched substrate to gain insight into the carbohydrate esterase activities of this hemicellulolytic rumen bacterium. The P. ruminicola 23 genome contains 16 genes predicted to encode carbohydrate esterase activity, and based on microarray data, four of these were upregulated >2-fold at the transcriptional level during growth on an ester-enriched oligosaccharide (XOS(FA,Ac)) from corn relative to a nonesterified fraction of corn oligosaccharides (AXOS). Four of the 16 esterases (Xyn10D-Fae1A, Axe1-6A, AxeA1, and Axe7A), including the two most highly induced esterases (Xyn10D-Fae1A and Axe1-6A), were heterologously expressed in Escherichia coli, purified, and biochemically characterized. All four enzymes showed the highest activity at physiologically relevant pH (6 to 7) and temperature (30 to 40°C) ranges. The P. ruminicola 23 Xyn10D-Fae1A (a carbohydrate esterase [CE] family 1 enzyme) released ferulic acid from methylferulate, wheat bran, corn fiber, and XOS(FA,Ac), a corn fiber-derived substrate enriched in O-acetyl and ferulic acid esters, but exhibited negligible activity on sugar acetates. As expected, the P. ruminicola Axe1-6A enzyme, which was predicted to possess two distinct esterase family domains (CE1 and CE6), released ferulic acid from the same substrates as Xyn10D-Fae1 and was also able to cleave O-acetyl ester bonds from various acetylated oligosaccharides (AcXOS). The P. ruminicola 23 AxeA1, which is not assigned to a CE family, and Axe7A (CE7) were found to be acetyl esterases that had activity toward a broad range of mostly nonpolymeric acetylated substrates along with AcXOS. All enzymes were inhibited by the proximal location of other side groups like 4-O-methylglucuronic acid, ferulic acid, or acetyl groups. The unique diversity of carbohydrate esterases in P. ruminicola 23 likely gives it the ability to hydrolyze substituents on the xylan backbone and enhances its capacity to efficiently degrade hemicellulose.
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Appeldoorn MM, Kabel MA, Van Eylen D, Gruppen H, Schols HA. Characterization of oligomeric xylan structures from corn fiber resistant to pretreatment and simultaneous saccharification and fermentation. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2010; 58:11294-301. [PMID: 20942461 DOI: 10.1021/jf102849x] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Corn fiber, a byproduct from the corn industry, would be a good source for bioethanol production if the hemicellulose, consisting of polymeric glucoronoarabinoxylans, can be degraded into fermentable sugars. Structural knowledge of the hemicellulose is needed to improve the enzymatic hydrolyses of corn fiber. Oligosaccharides that resisted a mild acid pretreatment and subsequent enzymatic hydrolysis, representing 50% of the starting material, were fractionated on reversed phase and size exclusion material and characterized. The oligosaccharides within each fraction were highly substituted by various compounds. Oligosaccharides containing uronic acid were accumulated in two polar fractions unless also a feruloyl group was present. Feruloylated oligosaccharides, containing mono- and/or diferulic acid, were accumulated within four more apolar fractions. All fractions contained high amounts of acetyl substituents. The data show that complex xylan oligomers are present in which ferulic acid, diferulates, acetic acid, galactose, arabinose, and uronic acids were combined within an oligomer. Hypothetical structures are discussed, demonstrating which enzyme activities are lacking to fully degrade corn glucuronoarabinoxylans.
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Affiliation(s)
- Maaike M Appeldoorn
- Laboratory of Food Chemistry, Wageningen University, Bomenweg 2, 6700 EV Wageningen, The Netherlands
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Sun XF, Fowler P, Rajaratnam M, Zhang G. Extraction and characterisation of hemicelluloses from maize stem. PHYTOCHEMICAL ANALYSIS : PCA 2010; 21:406-415. [PMID: 20333614 DOI: 10.1002/pca.1211] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
INTRODUCTION Extraction and characterisation of hemicelluloses are very important for converting them into functional materials and chemicals. OBJECTIVE To develop a method for isolation of hemicelluloses from all cell walls. METHODOLOGY Sequential steps using 90% dioxane, 80% acidic dioxane, 100% dimethyl sulphoxide and 8% NaOH were used for extraction of the hemicellulosic preparations (H(1), H(2), H(3) and H(4)) from maize stem. Advanced NMR techniques were used for the analysis of native hemicelluloses. RESULTS Hemicelluloses with high yieldd were isolated from all cell walls, and contained arabinoxylan as the major polysaccharide. H(3) was substituted by α-L-arabinofuranose, α-D-xylopyranose, and acetyl groups (degree of saturation = 0.12/0.09) at O-3/O-2 of xylan. H(4) had a long continuous side chain of arabinose residues, and associated closely with non-cellulosic glucose. The hemicelluloses formed more linkages with guaiacyl lignins, and some p-coumaric acids built a bridge between hemicelluloses and lignin in maize stem. CONCLUSION This modified method is successful for the isolation of hemicelluloses with high yields from all cell walls of maize stem.
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Affiliation(s)
- Xiao-Feng Sun
- Department of Applied Chemistry, College of Science, Northwestern Polytechnical University, Xi'an, 710072, China.
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Gullón P, González-Muñoz MJ, van Gool MP, Schols HA, Hirsch J, Ebringerová A, Parajó JC. Production, refining, structural characterization and fermentability of rice husk xylooligosaccharides. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2010; 58:3632-3641. [PMID: 20163183 DOI: 10.1021/jf904508g] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Oligosaccharides produced by hydrothermal processing of rice husks (xylooligosaccharides and glucooligosaccharides) were refined by membrane processing (operating in diafiltration and concentration modes), subjected to xylanase treatment to reduce the average molar mass, and subjected to further purification by ultrafiltration (operating in concentration mode) and ion exchange. The purified products were assayed for composition, molar mass distribution and structural characterization by HPLC, HPAEC-PAD, HPSEC, MALDI-TOF-MS and NMR ((1)H and (13)C). The fermentability of the purified product by fecal inocula was assessed on the basis of the time courses of pH and oligosaccharide concentrations. Succinate, lactate, formiate, acetate, propionate and butyrate were the major products resulting from fermentation experiments.
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Affiliation(s)
- Patricia Gullón
- Department of Chemical Engineering, Faculty of Science, University of Vigo (Campus Ourense), As Lagoas, Ourense, Spain
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Simões J, Nunes FM, Domingues MDRM, Coimbra MA. Structural features of partially acetylated coffee galactomannans presenting immunostimulatory activity. Carbohydr Polym 2010. [DOI: 10.1016/j.carbpol.2009.08.020] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Westphal Y, Schols H, Voragen A, Gruppen H. Introducing porous graphitized carbon liquid chromatography with evaporative light scattering and mass spectrometry detection into cell wall oligosaccharide analysis. J Chromatogr A 2010; 1217:689-95. [DOI: 10.1016/j.chroma.2009.12.005] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2009] [Revised: 11/16/2009] [Accepted: 12/02/2009] [Indexed: 11/16/2022]
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Mittal A, Scott GM, Amidon TE, Kiemle DJ, Stipanovic AJ. Quantitative analysis of sugars in wood hydrolyzates with 1H NMR during the autohydrolysis of hardwoods. BIORESOURCE TECHNOLOGY 2009; 100:6398-406. [PMID: 19674893 DOI: 10.1016/j.biortech.2009.06.107] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2008] [Revised: 06/18/2009] [Accepted: 06/27/2009] [Indexed: 05/16/2023]
Abstract
The focus of this work was to determine the utility of (1)H NMR spectroscopy in the quantification of sugars resulting from the solubilization of hemicelluloses during the autohydrolysis of hardwoods and the use of this technique to evaluate the kinetics of this process over a range of temperatures and times. Yields of residual xylan, xylooligomers, xylose, glucose, and the degraded products of sugars, i.e., furfural and HMF (5-hydroxymethyl furfural), were determined. The monosaccharide and oligomer contents were quantified with a recently developed high resolution (1)H NMR spectroscopic analysis. This method provided precise measurement of the residual xylan and cellulose remaining in the extracted wood samples and xylose and glucose in the hydrolyzates. NMR was found to exhibit good repeatability and provided carbohydrate compositional results comparable to published methods for sugar maple and aspen woods.
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Affiliation(s)
- Ashutosh Mittal
- Department of Paper and Bioprocess Engineering, SUNY College of Environmental Science and Forestry, 1 Forestry Drive, Syracuse, NY 13210, United States.
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Brecker L, Mahut M, Schwarz A, Nidetzky B. In situ proton NMR study of acetyl and formyl group migration in mono-O-acyl D-glucose. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2009; 47:328-332. [PMID: 19172587 DOI: 10.1002/mrc.2395] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Acetyl and formyl group migration, mutarotation, and hydrolysis of mono-O-acylated glucose are studied by in situ 1D and 2D (1)H NMR spectroscopy. Alpha-D-glucosyl-1-acetate and alpha-D-glucosyl-1-formate serve as sole starting materials. They are generated in situ by configuration retaining glucosyltransfer from alpha-D-glucosyl-1-phosphate to formate and acetate, which is catalyzed by the Glu-237 --> Gln mutant of Leuconostoc mesenteroides sucrose phosphorylase. Temporary accumulated regio-isomeric mono-O-acyl D-glucoses are identified, characterized, and quantified directly from the reaction mixture. Time courses of the transformations give insight into pH dependence of acyl group migration and mutarotation as well as into the stability of various regioisomers.
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Affiliation(s)
- Lothar Brecker
- University of Vienna, Department of Organic Chemistry, Währinger Strasse 38, A-1090 Wien, Austria.
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Harvey DJ. Analysis of carbohydrates and glycoconjugates by matrix-assisted laser desorption/ionization mass spectrometry: An update for 2003-2004. MASS SPECTROMETRY REVIEWS 2009; 28:273-361. [PMID: 18825656 PMCID: PMC7168468 DOI: 10.1002/mas.20192] [Citation(s) in RCA: 79] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2008] [Revised: 07/07/2008] [Accepted: 07/07/2008] [Indexed: 05/13/2023]
Abstract
This review is the third update of the original review, published in 1999, on the application of matrix-assisted laser desorption/ionization (MALDI) mass spectrometry to the analysis of carbohydrates and glycoconjugates and brings the topic to the end of 2004. Both fundamental studies and applications are covered. The main topics include methodological developments, matrices, fragmentation of carbohydrates and applications to large polymeric carbohydrates from plants, glycans from glycoproteins and those from various glycolipids. Other topics include the use of MALDI MS to study enzymes related to carbohydrate biosynthesis and degradation, its use in industrial processes, particularly biopharmaceuticals and its use to monitor products of chemical synthesis where glycodendrimers and carbohydrate-protein complexes are highlighted.
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Affiliation(s)
- David J Harvey
- Department of Biochemistry, Oxford Glycobiology Institute, University of Oxford, Oxford OX1 3QU, UK.
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Inoue H, Yano S, Endo T, Sakaki T, Sawayama S. Combining hot-compressed water and ball milling pretreatments to improve the efficiency of the enzymatic hydrolysis of eucalyptus. BIOTECHNOLOGY FOR BIOFUELS 2008; 1:2. [PMID: 18471309 PMCID: PMC2375867 DOI: 10.1186/1754-6834-1-2] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2007] [Accepted: 04/15/2008] [Indexed: 05/08/2023]
Abstract
BACKGROUND Lignocellulosic biomass such as wood is an attractive material for fuel ethanol production. Pretreatment technologies that increase the digestibility of cellulose and hemicellulose in the lignocellulosic biomass have a major influence on the cost of the subsequent enzymatic hydrolysis and ethanol fermentation processes. Pretreatments without chemicals such as acids, bases or organic solvents are less effective for an enzymatic hydrolysis process than those with chemicals, but they have a less negative effect on the environment. RESULTS The enzymatic digestibility of eucalyptus was examined following a combined pretreatment without chemicals comprising a ball milling (BM) and hot-compressed water (HCW) treatment. The BM treatment simultaneously improved the digestibility of both glucan and xylan, and was effective in lowering the enzyme loading compared with the HCW treatment. The combination of HCW and BM treatment reduced the BM time. The eucalyptus treated with HCW (160 degrees C, 30 minutes) followed by BM (20 minutes) had an approximately 70% yield of total sugar with a cellulase loading of 4 FPU/g substrate. This yield was comparable to the yields from samples treated with HCW (200 degrees C, 30 minutes) or BM (40 minutes) hydrolyzed with 40 FPU/g substrate. CONCLUSION The HCW treatment is useful in improving the milling efficiency. The combined HCW-BM treatment can save energy and enzyme loading.
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Affiliation(s)
- Hiroyuki Inoue
- Biomass Technology Research Center, National Institute of Advanced Industrial Science and Technology (AIST), 2-2-2 Hiro-Suehiro, Kure, Hiroshima 737-0197, Japan
| | - Shinichi Yano
- Biomass Technology Research Center, National Institute of Advanced Industrial Science and Technology (AIST), 2-2-2 Hiro-Suehiro, Kure, Hiroshima 737-0197, Japan
| | - Takashi Endo
- Biomass Technology Research Center, National Institute of Advanced Industrial Science and Technology (AIST), 2-2-2 Hiro-Suehiro, Kure, Hiroshima 737-0197, Japan
| | - Tsuyoshi Sakaki
- Biomass Technology Research Center, National Institute of Advanced Industrial Science and Technology (AIST), 2-2-2 Hiro-Suehiro, Kure, Hiroshima 737-0197, Japan
| | - Shigeki Sawayama
- Biomass Technology Research Center, National Institute of Advanced Industrial Science and Technology (AIST), 2-2-2 Hiro-Suehiro, Kure, Hiroshima 737-0197, Japan
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