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Long L, Lin Q, Wang J, Ding S. Microbial α-L-arabinofuranosidases: diversity, properties, and biotechnological applications. World J Microbiol Biotechnol 2024; 40:84. [PMID: 38294733 DOI: 10.1007/s11274-023-03882-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2023] [Accepted: 12/28/2023] [Indexed: 02/01/2024]
Abstract
Arabinoxylans (AXs) are hemicellulosic polysaccharides consisting of a linear backbone of β-1,4-linked xylose residues branched by high content of α-L-arabinofuranosyl (Araf) residues along with other side-chain substituents, and are abundantly found in various agricultural crops especially cereals. The efficient bioconversion of AXs into monosaccharides, oligosaccharides and/or other chemicals depends on the synergism of main-chain enzymes and de-branching enzymes. Exo-α-L-arabinofuranosidases (ABFs) catalyze the hydrolysis of terminal non-reducing α-1,2-, α-1,3- or α-1,5- linked α-L-Araf residues from arabinose-substituted polysaccharides or oligosaccharides. ABFs are critically de-branching enzymes in bioconversion of agricultural biomass, and have received special attention due to their application potentials in biotechnological industries. In recent years, the researches on microbial ABFs have developed quickly in the aspects of the gene mining, properties of novel members, catalytic mechanisms, methodologies, and application technologies. In this review, we systematically summarize the latest advances in microbial ABFs, and discuss the future perspectives of the enzyme research.
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Affiliation(s)
- Liangkun Long
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, People's Republic of China.
- Jiangsu Province Key Laboratory of Green Biomass-Based Fuels and Chemicals, Nanjing, 210037, People's Republic of China.
| | - Qunying Lin
- Nanjing Institute for the Comprehensive Utilization of Wild Plants, China CO-OP, Nanjing, 211111, People's Republic of China
| | - Jing Wang
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, People's Republic of China
| | - Shaojun Ding
- Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, People's Republic of China
- Jiangsu Province Key Laboratory of Green Biomass-Based Fuels and Chemicals, Nanjing, 210037, People's Republic of China
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2
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Bhaiyya R, Sharma SC, Singh RP. Biochemical characterization of bifunctional enzymatic activity of a recombinant protein (Bp0469) from Blautia producta ATCC 27340 and its role in the utilization of arabinogalactan oligosaccharides. Int J Biol Macromol 2023; 253:126736. [PMID: 37678698 DOI: 10.1016/j.ijbiomac.2023.126736] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Revised: 08/28/2023] [Accepted: 09/04/2023] [Indexed: 09/09/2023]
Abstract
Human consumption of larch arabinogalactan has a significant effect on enhancing probiotic microflora in the gut, and it also promotes the production of short-chain fatty acids. Bacterial members of Lachnospiraceae family are important and play significant roles in maintaining our gut health. However, it is less known about biochemistry of members of this family by which they utilize non-cellulosic fiber in the gut. For enhancing this understanding, we studied that B. producta ATCC 27340 grew on arabinogalactan oligosaccharides (AGOs) as compared to polysaccharide form of arabinogalactan. Recombinant protein (Bp0469) was heterologously expressed in Escherichia coli BL21 (DE3) and revealed the optimum pH and temperature at 7.4 in phosphate buffer and 45 °C, respectively. Catalytic efficiency of recombinant Bp0469 for p-nitrophenyl (pNP)-α-L-arabinofuranoside was about half of pNP-β-D-galactopyranoside. It also cleaved natural substrates (lactose, arabinobiose and 3-O-(β-d-galactopyranosyl)-d-galactopyranose) and characterized AGOs in this study. Based on genomic, structural models, and biochemical characteristics, identified Bp0469 is a peculiar enzyme with two distinct domains that cleave α1-5 linked arabinobiose and β-D-Galp-1-3/4 linkages. Overall, the study enhances the knowledge on nutritional perspective of B. producta ATCC 27340 for thriving on non-cellulosic biomass, and identified enzyme can also be used for producing industrial important AGOs.
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Affiliation(s)
- Raja Bhaiyya
- Department of Industrial Biotechnology, Gujarat Biotechnology University, North-Gate Gujarat International Finance Tec (GIFT)-City, Gandhinagar 382355, Gujarat, India; Division of Food and Nutritional Biotechnology, National Agri-Food Biotechnology Institute (NABI), SAS Nagar, Punjab 140306, India; Department of Biochemistry, South Campus, Panjab University, Chandigarh 160014, India
| | - Sukesh Chander Sharma
- Department of Biochemistry, South Campus, Panjab University, Chandigarh 160014, India
| | - Ravindra Pal Singh
- Department of Industrial Biotechnology, Gujarat Biotechnology University, North-Gate Gujarat International Finance Tec (GIFT)-City, Gandhinagar 382355, Gujarat, India; Division of Food and Nutritional Biotechnology, National Agri-Food Biotechnology Institute (NABI), SAS Nagar, Punjab 140306, India.
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3
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Si Z, Cai Y, Zhao L, Han L, Wang F, Yang X, Gao X, Lu M, Liu W. Structure and function characterization of the α-L-arabinofuranosidase from the white-rot fungus Trametes hirsuta. Appl Microbiol Biotechnol 2023:10.1007/s00253-023-12561-w. [PMID: 37178306 DOI: 10.1007/s00253-023-12561-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 04/17/2023] [Accepted: 04/19/2023] [Indexed: 05/15/2023]
Abstract
α-L-Arabinofuranosidases (Abfs) play a crucial role in the degradation of hemicelluloses, especially arabinoxylans (AX). Most of the available characterized Abfs are from bacteria, while fungi, as natural decomposers, contain Abfs with little attention given. An arabinofuranosidase (ThAbf1), belonging to the glycoside hydrolase 51 (GH51) family, from the genome of the white-rot fungus Trametes hirsuta, was recombinantly expressed, characterized, and functionally determined. The general biochemical properties showed that the optimal conditions for ThAbf1 were pH 6.0 and 50°C. In substrate kinetics assays, ThAbf1 preferred small fragment arabinoxylo-oligosaccharides (AXOS) and could surprisingly hydrolyze di-substituted 23,33-di-L-arabinofuranosyl-xylotriose (A2,3XX). It also synergized with commercial xylanase (XYL) and increased the saccharification efficiency of arabinoxylan. The crystal structure of ThAbf1 indicated the presence of an adjacent cavity next to the catalytic pocket which led to the ability of ThAbf1 to degrade di-substituted AXOS. The narrow binding pocket prevents ThAbf1 from binding larger substrates. These findings have strengthened our understanding of the catalytic mechanism of GH51 family Abfs and provided a theoretical foundation for the development of more efficient and versatile Abfs to accelerate the degradation and biotransformation of hemicellulose in biomass. KEY POINTS: • ThAbf1 from Trametes hirsuta degraded di-substituted arabinoxylo-oligosaccharide. • ThAbf1 performed detailed biochemical characterization and kinetics. • ThAbf1 structure has been obtained to illustrate the substrate specificity.
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Affiliation(s)
- Zhenyuan Si
- Jiangsu Key Laboratory of Druggability of Biopharmaceuticals, State Key Laboratory of Natural Medicines, College of Life Science and Technology, China Pharmaceutical University, Nanjing, 210009, PR China
| | - Yang Cai
- Jiangsu Key Laboratory of Druggability of Biopharmaceuticals, State Key Laboratory of Natural Medicines, College of Life Science and Technology, China Pharmaceutical University, Nanjing, 210009, PR China
| | - Lang Zhao
- Jiangsu Key Laboratory of Druggability of Biopharmaceuticals, State Key Laboratory of Natural Medicines, College of Life Science and Technology, China Pharmaceutical University, Nanjing, 210009, PR China
| | - Lu Han
- Jiangsu Key Laboratory of Druggability of Biopharmaceuticals, State Key Laboratory of Natural Medicines, College of Life Science and Technology, China Pharmaceutical University, Nanjing, 210009, PR China
| | - Feng Wang
- Simcere Pharmaceutical Group Limited, Nanjing, 210042, PR China
| | - Xiaobing Yang
- Biology and Medicine Department, Jiangsu Industrial Technology Research Institute, Nanjing, 210031, PR China
| | - Xiangdong Gao
- Jiangsu Key Laboratory of Druggability of Biopharmaceuticals, State Key Laboratory of Natural Medicines, College of Life Science and Technology, China Pharmaceutical University, Nanjing, 210009, PR China.
| | - Meiling Lu
- Jiangsu Key Laboratory of Druggability of Biopharmaceuticals, State Key Laboratory of Natural Medicines, College of Life Science and Technology, China Pharmaceutical University, Nanjing, 210009, PR China.
| | - Wei Liu
- Jiangsu Key Laboratory of Druggability of Biopharmaceuticals, State Key Laboratory of Natural Medicines, College of Life Science and Technology, China Pharmaceutical University, Nanjing, 210009, PR China.
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Dionisi HM, Lozada M, Campos E. Diversity of GH51 α-L-arabinofuranosidase homolog sequences from subantarctic intertidal sediments. Biologia (Bratisl) 2023. [DOI: 10.1007/s11756-023-01382-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/05/2023]
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Structure-function relationships of pectic polysaccharides from broccoli by-products with in vitro B lymphocyte stimulatory activity. Carbohydr Polym 2023; 303:120432. [PMID: 36657866 DOI: 10.1016/j.carbpol.2022.120432] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 11/18/2022] [Accepted: 12/01/2022] [Indexed: 12/12/2022]
Abstract
To study structure-function relationships of pectic polysaccharides with their immunostimulatory activity, broccoli by-products were used. Pectic polysaccharides composed by 64 mol% uronic acids, 18 mol% Ara, and 10 mol% Gal, obtained by hot water extraction, activated B lymphocytes in vitro (25-250 μg/mL). To disclose active structural features, combinations of ethanol and chromatographic fractionation and modification of the polysaccharides were performed. Polysaccharides insoluble in 80 % ethanol (Et80) showed higher immunostimulatory activity than the pristine mixture, which was independent of molecular weight range (12-400 kDa) and removal of terminal or short Ara side chains. Chemical sulfation did not promote B lymphocyte activation. However, the action of pectin methylesterase and endo-polygalacturonase on hot water extracted polysaccharides produced an acidic fraction with a high immunostimulatory activity. The de-esterified homogalacturonan region seem to be an important core to confer pectic polysaccharides immunostimulatory activity. Therefore, agri-food by-products are a source of pectic polysaccharide functional food ingredients.
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Production of a Fungal Punicalagin-Degrading Enzyme by Solid-State Fermentation: Studies of Purification and Characterization. Foods 2023; 12:foods12040903. [PMID: 36832976 PMCID: PMC9956360 DOI: 10.3390/foods12040903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Revised: 02/06/2023] [Accepted: 02/08/2023] [Indexed: 02/22/2023] Open
Abstract
The present work describes the purification of an enzyme capable of degrading punicalagin. The enzyme was produced by Aspergillus niger GH1 by solid-state fermentation, and the enzyme production was induced by using ellagitannins as the sole carbon source. The purification steps included the concentration by lyophilization, desalting, anionic exchange, and gel filtration chromatography. The enzyme kinetic constants were calculated by using punicalagin, methyl gallate, and sugar beet arabinans. The molecular mass of the protein was estimated by SDS-PAGE. The identified bands were excised and digested using trypsin, and the peptides were submitted to HPLC-MS/MS analysis. The docking analysis was conducted, and a 3D model was created. The purification fold increases 75 times compared with the cell-free extract. The obtained Km values were 0.053 mM, 0.53% and 6.66 mM for punicalagin, sugar beet arabinans and methyl gallate, respectively. The optimal pH and temperature for the reaction were 5 and 40 °C, respectively. The SDS-PAGE and native PAGE analysis revealed the presence of two bands identified as α-l-arabinofuranosidase. Both enzymes were capable of degrading punicalagin and releasing ellagic acid.
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The In Silico Characterization of Monocotyledonous α-l-Arabinofuranosidases on the Example of Maize. Life (Basel) 2023; 13:life13020266. [PMID: 36836625 PMCID: PMC9964162 DOI: 10.3390/life13020266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 12/26/2022] [Accepted: 01/14/2023] [Indexed: 01/20/2023] Open
Abstract
Plant α-l-arabinofuranosidases remove terminal arabinose from arabinose-containing substrates such as plant cell wall polysaccharides, including arabinoxylans, arabinogalactans, and arabinans. In plants, de-arabinosylation of cell wall polysaccharides accompanies different physiological processes such as fruit ripening and elongation growth. In this report, we address the diversity of plant α-l-arabinofuranosidases of the glycoside hydrolase (GH) family 51 through their phylogenetic analysis as well as their structural features. The CBM4-like domain at N-terminus was found to exist only in GH51 family proteins and was detected in almost 90% of plant sequences. This domain is similar to bacterial CBM4, but due to substitutions of key amino acid residues, it does not appear to be able to bind carbohydrates. Despite isoenzymes of GH51 being abundant, in particular in cereals, almost half of the GH51 proteins in Poales have a mutation of the acid/base residue in the catalytic site, making them potentially inactive. Open-source data on the transcription and translation of GH51 isoforms in maize were analyzed to discuss possible functions of individual isoenzymes. The results of homology modeling and molecular docking showed that the substrate binding site can accurately accommodate terminal arabinofuranose and that arabinoxylan is a more favorable ligand for all maize GH51 enzymes than arabinan.
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Sürmeli Y, Şanlı-Mohamed G. Structural and functional analyses of GH51 alpha-L-arabinofuranosidase of Geobacillus vulcani GS90 reveal crucial residues for catalytic activity and thermostability. Biotechnol Appl Biochem 2022. [PMID: 36455188 DOI: 10.1002/bab.2423] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Accepted: 06/16/2022] [Indexed: 12/04/2022]
Abstract
Alpha-L-arabinofuranosidase (Abf) is of big interest in various industrial areas. Directed evolution is a powerful strategy to identify significant residues underlying Abf properties. Here, six active variants from GH51 Abf of Geobacillus vulcani GS90 (GvAbf) by directed evolution were overproduced, extracted, and analyzed at biochemical and structural levels. According to the activity and thermostability results, the most-active and the least-active variants were found as GvAbf51 and GvAbf52, respectively. GvAbf63 variant was more active than parent GvAbf by 20% and less active than GvAbf51. Also, the highest thermostability belonged to GvAbf52 with 80% residual activity after 1 h. Comparative sequence and structure analyses revealed that GvAbf51 possessed L307S displacement. Thus, this study suggested that L307 residue may be critical for GvAbf activity. GvAbf63 had H30D, Q90H, and L307S displacements, and H30 was covalently bound to E29 catalytic residue. Thus, H30D may decrease the positive effect of L307S on GvAbf63 activity, preventing E29 action. Besides, GvAbf52 possessed S215N, L307S, H473P, and G476C substitutions and S215 was close to E175 (acid-base residue). S215N may partially disrupt E175 action. Overall effect of all substitutions in GvAbf52 may result in the formation of the C-C bond between C171 and C213 by becoming closer to each other.
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Affiliation(s)
- Yusuf Sürmeli
- Department of Biotechnology and Bioengineering, İzmir Institute of Technology, İzmir, Turkey.,Department of Agricultural Biotechnology, Tekirdağ Namık Kemal University, Tekirdağ, Turkey
| | - Gülşah Şanlı-Mohamed
- Department of Biotechnology and Bioengineering, İzmir Institute of Technology, İzmir, Turkey.,Department of Chemistry, İzmir Institute of Technology, İzmir, Turkey
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Saleh MA, Mahmud S, Albogami S, El-Shehawi AM, Paul GK, Islam S, Dutta AK, Uddin MS, Zaman S. Biochemical and Molecular Dynamics Study of a Novel GH 43 α-l-Arabinofuranosidase/β-Xylosidase From Caldicellulosiruptor saccharolyticus DSM8903. Front Bioeng Biotechnol 2022; 10:810542. [PMID: 35223784 PMCID: PMC8881100 DOI: 10.3389/fbioe.2022.810542] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2021] [Accepted: 01/07/2022] [Indexed: 11/13/2022] Open
Abstract
The complete hydrolysis of xylan can be facilitated by the coordinated action of xylanase and other de-branching enzymes. Here, a GH43 α-l-arabinofuranosidase/β-xylosidase (CAX43) from Caldicellulosiruptor saccharolyticus was cloned, sequenced, and biochemically investigated. The interaction of the enzyme with various substrates was also studied. With a half-life of 120 h at 70°C, the produced protein performed maximum activity at pH 6.0 and 70°C. The enzyme demonstrated a higher activity (271.062 ± 4.83 U/mg) against para nitrophenol (pNP) α-L-arabinofuranosides. With xylanase (XynA), the enzyme had a higher degree of synergy (2.30) in a molar ratio of 10:10 (nM). The interaction of the enzyme with three substrates, pNP α-L-arabinofuranosides, pNP β-D-xylopyranosides, and sugar beet arabinan, was investigated using protein modeling, molecular docking, and molecular dynamics (MD) simulation. During the simulation time, the root mean square deviation (RMSD) of the enzyme was below 2.5 Å, demonstrating structural stability. Six, five, and seven binding-interacting residues were confirmed against pNP α-L-arabinofuranosides, pNP β-D-xylopyranosides, and arabinan, respectively, in molecular docking experiments. This biochemical and in silico study gives a new window for understanding the GH43 family’s structural stability and substrate recognition, potentially leading to biological insights and rational enzyme engineering for a new generation of enzymes that perform better and have greater biorefinery utilization.
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Affiliation(s)
- Md. Abu Saleh
- Microbiology Laboratory, Department of Genetic Engineering and Biotechnology, University of Rajshahi, Rajshahi, Bangladesh
- *Correspondence: Md. Abu Saleh,
| | - Shafi Mahmud
- Microbiology Laboratory, Department of Genetic Engineering and Biotechnology, University of Rajshahi, Rajshahi, Bangladesh
| | - Sarah Albogami
- Department of Biotechnology, College of Science, Taif University, Taif, Saudi Arabia
| | - Ahmed M El-Shehawi
- Department of Biotechnology, College of Science, Taif University, Taif, Saudi Arabia
| | - Gobindo Kumar Paul
- Microbiology Laboratory, Department of Genetic Engineering and Biotechnology, University of Rajshahi, Rajshahi, Bangladesh
| | - Shirmin Islam
- Microbiology Laboratory, Department of Genetic Engineering and Biotechnology, University of Rajshahi, Rajshahi, Bangladesh
| | - Amit Kumar Dutta
- Department of Microbiology, University of Rajshahi, Rajshahi, Bangladesh
| | - Md. Salah Uddin
- Microbiology Laboratory, Department of Genetic Engineering and Biotechnology, University of Rajshahi, Rajshahi, Bangladesh
| | - Shahriar Zaman
- Microbiology Laboratory, Department of Genetic Engineering and Biotechnology, University of Rajshahi, Rajshahi, Bangladesh
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Villa-Rivera MG, Cano-Camacho H, López-Romero E, Zavala-Páramo MG. The Role of Arabinogalactan Type II Degradation in Plant-Microbe Interactions. Front Microbiol 2021; 12:730543. [PMID: 34512607 PMCID: PMC8424115 DOI: 10.3389/fmicb.2021.730543] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Accepted: 08/04/2021] [Indexed: 11/13/2022] Open
Abstract
Arabinogalactans (AGs) are structural polysaccharides of the plant cell wall. A small proportion of the AGs are associated with hemicellulose and pectin. Furthermore, AGs are associated with proteins forming the so-called arabinogalactan proteins (AGPs), which can be found in the plant cell wall or attached through a glycosylphosphatidylinositol (GPI) anchor to the plasma membrane. AGPs are a family of highly glycosylated proteins grouped with cell wall proteins rich in hydroxyproline. These glycoproteins have important and diverse functions in plants, such as growth, cellular differentiation, signaling, and microbe-plant interactions, and several reports suggest that carbohydrate components are crucial for AGP functions. In beneficial plant-microbe interactions, AGPs attract symbiotic species of fungi or bacteria, promote the development of infectious structures and the colonization of root tips, and furthermore, these interactions can activate plant defense mechanisms. On the other hand, plants secrete and accumulate AGPs at infection sites, creating cross-links with pectin. As part of the plant cell wall degradation machinery, beneficial and pathogenic fungi and bacteria can produce the enzymes necessary for the complete depolymerization of AGs including endo-β-(1,3), β-(1,4) and β-(1,6)-galactanases, β-(1,3/1,6) galactanases, α-L-arabinofuranosidases, β-L-arabinopyranosidases, and β-D-glucuronidases. These hydrolytic enzymes are secreted during plant-pathogen interactions and could have implications for the function of AGPs. It has been proposed that AGPs could prevent infection by pathogenic microorganisms because their degradation products generated by hydrolytic enzymes of pathogens function as damage-associated molecular patterns (DAMPs) eliciting the plant defense response. In this review, we describe the structure and function of AGs and AGPs as components of the plant cell wall. Additionally, we describe the set of enzymes secreted by microorganisms to degrade AGs from AGPs and its possible implication for plant-microbe interactions.
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Affiliation(s)
- Maria Guadalupe Villa-Rivera
- Departamento de Ingeniería Genética, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Irapuato, Mexico
| | - Horacio Cano-Camacho
- Centro Multidisciplinario de Estudios en Biotecnología, FMVZ, Universidad Michoacana de San Nicolás de Hidalgo, Tarímbaro, Mexico
| | - Everardo López-Romero
- División de Ciencias Naturales y Exactas, Departamento de Biología, Universidad de Guanajuato, Guanajuato, Mexico
| | - María Guadalupe Zavala-Páramo
- Centro Multidisciplinario de Estudios en Biotecnología, FMVZ, Universidad Michoacana de San Nicolás de Hidalgo, Tarímbaro, Mexico
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Cabezas-Pérusse Y, Daligault F, Ferrières V, Tasseau O, Tranchimand S. Modulation of the Activity and Regioselectivity of a Glycosidase: Development of a Convenient Tool for the Synthesis of Specific Disaccharides. Molecules 2021; 26:5445. [PMID: 34576917 PMCID: PMC8468180 DOI: 10.3390/molecules26185445] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 08/24/2021] [Accepted: 09/02/2021] [Indexed: 11/17/2022] Open
Abstract
The synthesis of disaccharides, particularly those containing hexofuranoside rings, requires a large number of steps by classical chemical means. The use of glycosidases can be an alternative to limit the number of steps, as they catalyze the formation of controlled glycosidic bonds starting from simple and easy to access building blocks; the main drawbacks are the yields, due to the balance between the hydrolysis and transglycosylation of these enzymes, and the enzyme-dependent regioselectivity. To improve the yield of the synthesis of β-d-galactofuranosyl-(1→X)-d-mannopyranosides catalyzed by an arabinofuranosidase, in this study we developed a strategy to mutate, then screen the catalyst, followed by a tailored molecular modeling methodology to rationalize the effects of the identified mutations. Two mutants with a 2.3 to 3.8-fold increase in transglycosylation yield were obtained, and in addition their accumulated regioisomer kinetic profiles were very different from the wild-type enzyme. Those differences were studied in silico by docking and molecular dynamics, and the methodology revealed a good predictive quality in regards with the regioisomer profiles, which is in good agreement with the experimental transglycosylation kinetics. So, by engineering CtAraf51, new biocatalysts were enabled to obtain the attractive central motif from the Leishmania lipophosphoglycan core with a higher yield and regioselectivity.
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Affiliation(s)
- Yari Cabezas-Pérusse
- Ecole Nationale Supérieure de Chimie de Rennes, CNRS, ISCR (Institut des Sciences Chimiques de Rennes)—UMR 6226, Université de Rennes, F-35000 Rennes, France; (Y.C.-P.); (V.F.); (O.T.)
| | - Franck Daligault
- CNRS, UFIP (Unité de Fonctionnalité et Ingénierie des Protéines)—UMR 6286, Université de Nantes, F-44000 Nantes, France;
| | - Vincent Ferrières
- Ecole Nationale Supérieure de Chimie de Rennes, CNRS, ISCR (Institut des Sciences Chimiques de Rennes)—UMR 6226, Université de Rennes, F-35000 Rennes, France; (Y.C.-P.); (V.F.); (O.T.)
| | - Olivier Tasseau
- Ecole Nationale Supérieure de Chimie de Rennes, CNRS, ISCR (Institut des Sciences Chimiques de Rennes)—UMR 6226, Université de Rennes, F-35000 Rennes, France; (Y.C.-P.); (V.F.); (O.T.)
| | - Sylvain Tranchimand
- Ecole Nationale Supérieure de Chimie de Rennes, CNRS, ISCR (Institut des Sciences Chimiques de Rennes)—UMR 6226, Université de Rennes, F-35000 Rennes, France; (Y.C.-P.); (V.F.); (O.T.)
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Liu Y, Vanderhaeghen S, Feiler W, Angelov A, Baudrexl M, Zverlov V, Liebl W. Characterization of Two α-l-Arabinofuranosidases from Acetivibrio mesophilus and Their Synergistic Effect in Degradation of Arabinose-Containing Substrates. Microorganisms 2021; 9:microorganisms9071467. [PMID: 34361903 PMCID: PMC8307384 DOI: 10.3390/microorganisms9071467] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 07/05/2021] [Accepted: 07/06/2021] [Indexed: 11/16/2022] Open
Abstract
Arabinofuranosidases are important accessory enzymes involved in the degradation of arabinose-containing poly- and oligosaccharides. Two arabinofuranosidases from the recently described novel anaerobic cellulolytic bacterium Acetivibrio mesophilus, designated AmAraf51 and AmAraf43, were heterologously expressed in Escherichia coli and biochemically characterized. AmAraf51 not only removed arabinose moieties at O-3, O-2 and terminal O-5 positions of arabinose-containing oligosaccharides, but also exhibited exo-β-xylosidase side activity. In comparison, AmAraf43 preferably cleaved 1,3-linkages from arabinosyl disubstitutions. AmAraf51 and AmAraf43 demonstrated maximum activity at 70 °C and 57 °C, respectively. Judging from the genetic context and substrate specificity, AmAraf51 may decompose internalized arabino/xylo-oligosaccharides. The embedding of the AmAraf43 gene between genes for several putative xylanolytic enzymes, along with its enzymatic properties suggests that AmAraf43 cleaves arabinose decorations from heteroxylans extracellularly. The enzymes revealed completely converse activity profiles towards arabinan/arabinoxylan: AmAraf51 displayed strong activity on arabinan, while AmAraf43 prefers arabinoxylan. AmAraf51 dramatically stimulated the saccharification level of wheat arabinoxylan (WAX-RS) and sugar beet arabinan when administered along with xylanase M_Xyn10 or arabinanase PpAbn43, respectively. For WAX-RS degradation, the yield of arabinose and xylose was boosted 13.77-fold and 4.96-fold, respectively. The bifunctional activity, thermostability and high catalytic efficiency make AmAraf51 an interesting candidate for industrial applications.
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13
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Two Key Amino Acids Variant of α-l-arabinofuranosidase from Bacillus subtilis Str. 168 with Altered Activity for Selective Conversion Ginsenoside Rc to Rd. Molecules 2021; 26:molecules26061733. [PMID: 33808840 PMCID: PMC8003784 DOI: 10.3390/molecules26061733] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2021] [Revised: 03/16/2021] [Accepted: 03/18/2021] [Indexed: 02/08/2023] Open
Abstract
α-l-arabinofuranosidase is a subfamily of glycosidases involved in the hydrolysis of l-arabinofuranosidic bonds, especially in those of the terminal non-reducing arabinofuranosyl residues of glycosides, from which efficient glycoside hydrolases can be screened for the transformation of ginsenosides. In this study, the ginsenoside Rc-hydrolyzing α-l-arabinofuranosidase gene, BsAbfA, was cloned from Bacilus subtilis, and its codons were optimized for efficient expression in E. coli BL21 (DE3). The recombinant protein BsAbfA fused with an N-terminal His-tag was overexpressed and purified, and then subjected to enzymatic characterization. Site-directed mutagenesis of BsAbfA was performed to verify the catalytic site, and the molecular mechanism of BsAbfA catalyzing ginsenoside Rc was analyzed by molecular docking, using the homology model of sequence alignment with other β-glycosidases. The results show that the purified BsAbfA had a specific activity of 32.6 U/mg. Under optimal conditions (pH 5, 40 °C), the kinetic parameters Km of BsAbfA for pNP-α-Araf and ginsenoside Rc were 0.6 mM and 0.4 mM, while the Kcat/Km were 181.5 s-1 mM-1 and 197.8 s-1 mM-1, respectively. More than 90% of ginsenoside Rc could be transformed by 12 U/mL purified BsAbfA at 40 °C and pH 5 in 24 h. The results of molecular docking and site-directed mutagenesis suggested that the E173 and E292 variants for BsAbfA are important in recognizing ginsenoside Rc effectively, and to make it enter the active pocket to hydrolyze the outer arabinofuranosyl moieties at C20 position. These remarkable properties and the catalytic mechanism of BsAbfA provide a good alternative for the effective biotransformation of the major ginsenoside Rc into Rd.
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14
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McGregor NGS, Turkenburg JP, Mørkeberg Krogh KBR, Nielsen JE, Artola M, Stubbs KA, Overkleeft HS, Davies GJ. Structure of a GH51 α-L-arabinofuranosidase from Meripilus giganteus: conserved substrate recognition from bacteria to fungi. Acta Crystallogr D Struct Biol 2020; 76:1124-1133. [PMID: 33135683 PMCID: PMC7604909 DOI: 10.1107/s205979832001253x] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Accepted: 09/14/2020] [Indexed: 03/17/2023] Open
Abstract
α-L-Arabinofuranosidases from glycoside hydrolase family 51 use a stereochemically retaining hydrolytic mechanism to liberate nonreducing terminal α-L-arabinofuranose residues from plant polysaccharides such as arabinoxylan and arabinan. To date, more than ten fungal GH51 α-L-arabinofuranosidases have been functionally characterized, yet no structure of a fungal GH51 enzyme has been solved. In contrast, seven bacterial GH51 enzyme structures, with low sequence similarity to the fungal GH51 enzymes, have been determined. Here, the crystallization and structural characterization of MgGH51, an industrially relevant GH51 α-L-arabinofuranosidase cloned from Meripilus giganteus, are reported. Three crystal forms were grown in different crystallization conditions. The unliganded structure was solved using sulfur SAD data collected from a single crystal using the I23 in vacuo diffraction beamline at Diamond Light Source. Crystal soaks with arabinose, 1,4-dideoxy-1,4-imino-L-arabinitol and two cyclophellitol-derived arabinose mimics reveal a conserved catalytic site and conformational itinerary between fungal and bacterial GH51 α-L-arabinofuranosidases.
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Affiliation(s)
- Nicholas G. S. McGregor
- York Structural Biology Laboratory, University of York, Heslington, York YO10 5DD, United Kingdom
| | - Johan P. Turkenburg
- York Structural Biology Laboratory, University of York, Heslington, York YO10 5DD, United Kingdom
| | | | - Jens Erik Nielsen
- Protein Biochemistry and Stability, Novozymes A/S, Krogshøjvej 36, 2880 Bagsvaerd, Denmark
| | - Marta Artola
- Leiden Institute of Chemistry, Leiden University, Einsteinweg 55, 2300 RA Leiden, The Netherlands
| | - Keith A. Stubbs
- School of Molecular Sciences, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia
| | - Herman S. Overkleeft
- Leiden Institute of Chemistry, Leiden University, Einsteinweg 55, 2300 RA Leiden, The Netherlands
| | - Gideon J. Davies
- York Structural Biology Laboratory, University of York, Heslington, York YO10 5DD, United Kingdom
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15
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Long L, Sun L, Lin Q, Ding S, St John FJ. Characterization and functional analysis of two novel thermotolerant α-L-arabinofuranosidases belonging to glycoside hydrolase family 51 from Thielavia terrestris and family 62 from Eupenicillium parvum. Appl Microbiol Biotechnol 2020; 104:8719-8733. [PMID: 32880690 PMCID: PMC7502447 DOI: 10.1007/s00253-020-10867-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Revised: 08/06/2020] [Accepted: 08/26/2020] [Indexed: 11/26/2022]
Abstract
Abstract Arabinofuranose substitutions on xylan are known to interfere with enzymatic hydrolysis of this primary hemicellulose. In this work, two novel α-l-arabinofuranosidases (ABFs), TtABF51A from Thielavia terrestris and EpABF62C from Eupenicillium parvum, were characterized and functionally analyzed. From sequences analyses, TtABF51A and EpABF62C belong to glycoside hydrolase (GH) families 51 and 62, respectively. Recombinant TtABF51A showed high activity on 4-nitrophenyl-α-l-arabinofuranoside (83.39 U/mg), low-viscosity wheat arabinoxylan (WAX, 39.66 U/mg), high-viscosity rye arabinoxylan (RAX, 32.24 U/mg), and sugarbeet arabinan (25.69 U/mg), while EpABF62C preferred to degrade arabinoxylan. For EpABF62C, the rate of hydrolysis of RAX (94.10 U/mg) was 2.1 times that of WAX (45.46 U/mg). The optimal pH and reaction temperature for the two enzymes was between 4.0 and 4.5 and 65 °C, respectively. Calcium played an important role in the thermal stability of EpABF62C. TtABF51A and EpABF62C showed the highest thermal stabilities at pH 4.5 or 5.0, respectively. At their optimal pHs, TtABF51A and EpABF62C retained greater than 80% of their initial activities after incubation at 55 °C for 96 h or 144 h, respectively. 1H NMR analysis indicated that the two enzymes selectively removed arabinose linked to C-3 of mono-substituted xylose residues in WAX. Compared with the singular application of the GH10 xylanase EpXYN1 from E. parvum, co-digestions of WAX including TtABF51A and/or EpABF62C released 2.49, 3.38, and 4.81 times xylose or 3.38, 1.65, and 2.57 times of xylobiose, respectively. Meanwhile, the amount of arabinose released from WAX by TtABF51A with EpXYN1 was 2.11 times the amount with TtABF51A alone. Key points • Two novel α-l-arabinofuranosidases (ABFs) displayed high thermal stability. • The thermal stability of GH62 family EpABF62C was dependent on calcium. • Buffer pH affects the thermal stability of the two ABFs. • Both ABFs enhance the hydrolysis of WAX by a GH10 xylanase. Electronic supplementary material The online version of this article (10.1007/s00253-020-10867-7) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Liangkun Long
- College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, China
- Institute for Microbial and Biochemical Technology, Forest Products Laboratory, USDA Forest Service, One Gifford Pinchot Drive, Madison, WI, 53726, USA
| | - Lu Sun
- College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, China
| | - Qunying Lin
- Nanjing Institute for the Comprehensive Utilization of Wild Plants, Nanjing, 211111, China
| | - Shaojun Ding
- College of Chemical Engineering, Nanjing Forestry University, Nanjing, 210037, China.
| | - Franz J St John
- Institute for Microbial and Biochemical Technology, Forest Products Laboratory, USDA Forest Service, One Gifford Pinchot Drive, Madison, WI, 53726, USA.
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Thakur A, Sharma K, Jamaldheen SB, Goyal A. Molecular Characterization, Regioselective and Synergistic Action of First Recombinant Type III α-L-arabinofuranosidase of Family 43 Glycoside Hydrolase (PsGH43_12) from Pseudopedobacter saltans. Mol Biotechnol 2020; 62:443-455. [DOI: 10.1007/s12033-020-00263-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/17/2020] [Indexed: 01/26/2023]
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17
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Cloning and Characterization of a Ginsenoside-Hydrolyzing α-L-Arabinofuranosidase, CaAraf51, From Cellulosimicrobium aquatile Lyp51. Curr Microbiol 2020; 77:2783-2791. [PMID: 32535650 DOI: 10.1007/s00284-020-02078-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Accepted: 06/04/2020] [Indexed: 12/22/2022]
Abstract
Moutai Jiuqu is a famous aromatic raw material of Maotai flavor liquor in China. It is brewed at high temperature and contains many kinds of bacteria, molds, and yeasts. There are many useful glycoside hydrolases in these microfloras, from which efficient glycoside hydrolases can be screened for biotransformation of natural saponins. In this study, an α-L-arabinofuranosidase gene (CaAraf51, 1524 bp, 507 amino acid, 55.07 kDa, and pI = 4.8) was cloned from Cellulosimicrobium aquatile Lyp51, which was isolated from the Maotai Jiuqu. The CaAraf51 was heterogeneously expressed in E. coli BL21 (DE3) and purified by N-terminal His-tag with the Ni2+-affinity column chromatography. The results show that purified CaAraf51 has a 6.8-fold purification factor and specific activity of 15 U/mg. Under optimal conditions (pH 5.0, temperature 40 °C), kinetic parameters Km of CaAraf51 for pNPαAraf and Rc were 1.1 and 0.57 mM, the Vmax were 25 and 6.25 μmol/min/mg, respectively. 90% of 0.87 mg Rc substrate can be transformed by 9.6 U purified CaAraf51 in 1 mL reaction system under suitable conditions (30 °C, pH 7.5 phosphate buffer, 1 h). In addition, we also tested the effects of metal ions and chemical agents on the activity of CaAraf51. According to systematically studied its function and enzymatic properties, CaAraf51 has excellent value and potential of biotransformation Rc into Rd.
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18
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Kobayashi M, Kumagai Y, Yamamoto Y, Yasui H, Kishimura H. Identification of a Key Enzyme for the Hydrolysis of β-(1→3)-Xylosyl Linkage in Red Alga Dulse Xylooligosaccharide from Bifidobacterium Adolescentis. Mar Drugs 2020; 18:E174. [PMID: 32245121 PMCID: PMC7142710 DOI: 10.3390/md18030174] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Revised: 03/10/2020] [Accepted: 03/18/2020] [Indexed: 01/15/2023] Open
Abstract
Red alga dulse possesses a unique xylan, which is composed of a linear β-(1→3)/β-(1→4)-xylosyl linkage. We previously prepared characteristic xylooligosaccharide (DX3, (β-(1→3)-xylosyl-xylobiose)) from dulse. In this study, we evaluated the prebiotic effect of DX3 on enteric bacterium. Although DX3 was utilized by Bacteroides sp. and Bifidobacterium adolescentis, Bacteroides Ksp. grew slowly as compared with β-(1→4)-xylotriose (X3) but B. adolescentis grew similar to X3. Therefore, we aimed to find the key DX3 hydrolysis enzymes in B. adolescentis. From bioinformatics analysis, two enzymes from the glycoside hydrolase family 43 (BAD0423: subfamily 12 and BAD0428: subfamily 11) were selected and expressed in Escherichia coli. BAD0423 hydrolyzed β-(1→3)-xylosyl linkage in DX3 with the specific activity of 2988 mU/mg producing xylose (X1) and xylobiose (X2), and showed low activity on X2 and X3. BAD0428 showed high activity on X2 and X3 producing X1, and the activity of BAD0428 on DX3 was 1298 mU/mg producing X1. Cooperative hydrolysis of DX3 was found in the combination of BAD0423 and BAD0428 producing X1 as the main product. From enzymatic character, hydrolysis of X3 was completed by one enzyme BAD0428, whereas hydrolysis of DX3 needed more than two enzymes.
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Affiliation(s)
- Manami Kobayashi
- Chair of Marine Chemical Resource Development, Graduate School of Fisheries Sciences, Hokkaido University, Hakodate 041-8611, Hokkaido, Japan (Y.Y.)
| | - Yuya Kumagai
- Laboratory of Marine Chemical Resource Development, Faculty of Fisheries Sciences, Hokkaido University, Hakodate 041-8611, Hokkaido, Japan;
| | - Yohei Yamamoto
- Chair of Marine Chemical Resource Development, Graduate School of Fisheries Sciences, Hokkaido University, Hakodate 041-8611, Hokkaido, Japan (Y.Y.)
| | - Hajime Yasui
- Laboratory of Humans and the Ocean, Faculty of Fisheries Sciences, Hokkaido University, Hakodate 041-8611, Hokkaido, Japan;
| | - Hideki Kishimura
- Laboratory of Marine Chemical Resource Development, Faculty of Fisheries Sciences, Hokkaido University, Hakodate 041-8611, Hokkaido, Japan;
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19
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Galactofuranosidase from JHA 19 Streptomyces sp.: subcloning and biochemical characterization. Carbohydr Res 2019; 480:35-41. [PMID: 31174175 DOI: 10.1016/j.carres.2019.05.011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Revised: 05/16/2019] [Accepted: 05/22/2019] [Indexed: 02/06/2023]
Abstract
Despite the crucial role of the rare galactofuranose (Galf) in many pathogenic micro-organisms and our increased knowledge of its metabolism, there is still a lack of recombinant and efficient galactofuranoside hydrolase available for chemo-enzymatic synthetic purposes of specific galactofuranosyl-conjugates. Subcloning of the Galf-ase from JHA 19 Streptomyces sp. and its further overexpression lead us to the production of this enzyme with a yield of 0.5 mg/L of culture. It exhibits substrate specificity exclusively towards pNP β-d-Galf, giving a KM value of 250 μM, and the highest enzymatic efficiency ever observed of 14 mM-1 s-1. It proved to be stable to temperature up to 60 °C and to at least 4 freeze-thaw's cycles. Thus, Galf-ase demonstrated to be an efficient and stable biocatalyst with greatly improved specificity toward the galactofuranosyl entity, thus paving the way to the further development of transglycosylation and thioligation reactions.
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20
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Highly thermostable GH51 α-arabinofuranosidase from Hungateiclostridium clariflavum DSM 19732. Appl Microbiol Biotechnol 2019; 103:3783-3793. [DOI: 10.1007/s00253-019-09753-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2018] [Revised: 02/18/2019] [Accepted: 03/06/2019] [Indexed: 10/27/2022]
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21
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α-l-Arabinofuranosidase: A Potential Enzyme for the Food Industry. ENERGY, ENVIRONMENT, AND SUSTAINABILITY 2019. [DOI: 10.1007/978-981-13-3263-0_12] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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22
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Pavic Q, Pillot A, Tasseau O, Legentil L, Tranchimand S. Improvement of the versatility of an arabinofuranosidase against galactofuranose for the synthesis of galactofuranoconjugates. Org Biomol Chem 2019; 17:6799-6808. [DOI: 10.1039/c9ob01162e] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
A new performant biocatalyst was developed for the synthesis ofO-,S- and acyl-galactofuranoconjugates.
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Affiliation(s)
- Quentin Pavic
- Univ Rennes
- Ecole Nationale Supérieure de Chimie de Rennes
- CNRS
- ISCR – UMR 6226
- F-35000 Rennes
| | - Aline Pillot
- Univ Rennes
- Ecole Nationale Supérieure de Chimie de Rennes
- CNRS
- ISCR – UMR 6226
- F-35000 Rennes
| | - Olivier Tasseau
- Univ Rennes
- Ecole Nationale Supérieure de Chimie de Rennes
- CNRS
- ISCR – UMR 6226
- F-35000 Rennes
| | - Laurent Legentil
- Univ Rennes
- Ecole Nationale Supérieure de Chimie de Rennes
- CNRS
- ISCR – UMR 6226
- F-35000 Rennes
| | - Sylvain Tranchimand
- Univ Rennes
- Ecole Nationale Supérieure de Chimie de Rennes
- CNRS
- ISCR – UMR 6226
- F-35000 Rennes
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23
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Gao J, Zhao Y, Zhang G, Li Y, Li Q. Production optimization, purification, expression, and characterization of a novel α-l-arabinofuranosidase from Paenibacillus polymyxa. ELECTRON J BIOTECHN 2018. [DOI: 10.1016/j.ejbt.2018.09.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022] Open
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24
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Mendis M, Leclerc E, Simsek S. Arabinoxylan hydrolyzates as immunomodulators in Caco-2 and HT-29 colon cancer cell lines. Food Funct 2018; 8:220-231. [PMID: 27966731 DOI: 10.1039/c6fo00866f] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The use of plant derived polysaccharides as health promoters has gained immense interest in the past few years. Arabinoxylan (AX) is the predominant non-starch polysaccharide in cereals and grasses including wheat. The current research aimed to investigate the structure-function relationship of arabinoxylan hydrolyzates (AXH), obtained by the enzymatic hydrolysis of AX using xylanase and arabinofuranosidase as immunomodulators in two colon cancer cell lines: Caco-2 and HT-29. Fine structural details had a strong correlation with the immunological properties of the wheat AXH. As a general trend, as the presence of arabinose substitution increased in the AXH, the production of proinflammatory cytokines, IL-8 and TNF-α, decreased in both cell lines. Thus, AXH with a higher degree of arabinose substitution might be better adept in lowering inflammation in colon cancer cells.
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Affiliation(s)
- Mihiri Mendis
- North Dakota State University, Department of Plant Sciences, P.O. Box 6050, Department 7670, Fargo, ND 58105, USA.
| | - Estelle Leclerc
- North Dakota State University, Department of Pharmaceutical Sciences, College of Health Professions, Fargo, ND, USA
| | - Senay Simsek
- North Dakota State University, Department of Plant Sciences, P.O. Box 6050, Department 7670, Fargo, ND 58105, USA.
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25
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A thermophilic α-l-Arabinofuranosidase from Geobacillus vulcani GS90: heterologous expression, biochemical characterization, and its synergistic action in fruit juice enrichment. Eur Food Res Technol 2018. [DOI: 10.1007/s00217-018-3075-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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26
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Ferreira SS, Passos CP, Cepeda MR, Lopes GR, Teixeira-Coelho M, Madureira P, Nunes FM, Vilanova M, Coimbra MA. Structural polymeric features that contribute to in vitro immunostimulatory activity of instant coffee. Food Chem 2018; 242:548-554. [DOI: 10.1016/j.foodchem.2017.09.059] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Revised: 07/31/2017] [Accepted: 09/12/2017] [Indexed: 02/06/2023]
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27
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de Camargo BR, Claassens NJ, Quirino BF, Noronha EF, Kengen SW. Heterologous expression and characterization of a putative glycoside hydrolase family 43 arabinofuranosidase from Clostridium thermocellum B8. Enzyme Microb Technol 2018; 109:74-83. [DOI: 10.1016/j.enzmictec.2017.09.014] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Revised: 09/28/2017] [Accepted: 09/30/2017] [Indexed: 11/30/2022]
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28
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Pavic Q, Tranchimand S, Lemiègre L, Legentil L. Diversion of a thioglycoligase for the synthesis of 1-O-acyl arabinofuranoses. Chem Commun (Camb) 2018; 54:5550-5553. [DOI: 10.1039/c8cc01726c] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
An arabinofuranosylhydrolase from the GH51 family was transformed into an acyl transferase by mutation of the catalytic acid/base amino acid.
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Affiliation(s)
- Quentin Pavic
- Univ Rennes
- Ecole Nationale Supérieure de Chimie de Rennes
- CNRS
- ISCR – UMR 6226
- F-35000 Rennes
| | - Sylvain Tranchimand
- Univ Rennes
- Ecole Nationale Supérieure de Chimie de Rennes
- CNRS
- ISCR – UMR 6226
- F-35000 Rennes
| | - Loïc Lemiègre
- Univ Rennes
- Ecole Nationale Supérieure de Chimie de Rennes
- CNRS
- ISCR – UMR 6226
- F-35000 Rennes
| | - Laurent Legentil
- Univ Rennes
- Ecole Nationale Supérieure de Chimie de Rennes
- CNRS
- ISCR – UMR 6226
- F-35000 Rennes
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29
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Jia L, Minamihata K, Ichinose H, Tsumoto K, Kamiya N. Polymeric SpyCatcher Scaffold Enables Bioconjugation in a Ratio-Controllable Manner. Biotechnol J 2017; 12. [DOI: 10.1002/biot.201700195] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Revised: 09/16/2017] [Indexed: 01/05/2023]
Affiliation(s)
- Lili Jia
- Department of Applied Chemistry; Graduate School of Engineering; Kyushu University; 744 Motooka Fukuoka 819-0395 Japan
| | - Kosuke Minamihata
- Department of Applied Chemistry; Graduate School of Engineering; Kyushu University; 744 Motooka Fukuoka 819-0395 Japan
| | - Hirofumi Ichinose
- Faculty of Agriculture; Kyushu University; Hakozaki 6-10-1 Higashi-ku Fukuoka 812-8581 Japan
| | - Kouhei Tsumoto
- Department of Chemistry and Biotechnology; The University of Tokyo; 7-3-1 Hongo Bunkyo-ku Tokyo 113-8656 Japan
| | - Noriho Kamiya
- Department of Applied Chemistry; Graduate School of Engineering; Kyushu University; 744 Motooka Fukuoka 819-0395 Japan
- Division of Biotechnology; Center for Future Chemistry; Kyushu University; Fukuoka 819-0388 Japan
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30
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Enzymatic Mechanism for Arabinan Degradation and Transport in the Thermophilic Bacterium Caldanaerobius polysaccharolyticus. Appl Environ Microbiol 2017; 83:AEM.00794-17. [PMID: 28710263 DOI: 10.1128/aem.00794-17] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2017] [Accepted: 07/05/2017] [Indexed: 12/21/2022] Open
Abstract
The plant cell wall polysaccharide arabinan provides an important supply of arabinose, and unraveling arabinan-degrading strategies by microbes is important for understanding its use as a source of energy. Here, we explored the arabinan-degrading enzymes in the thermophilic bacterium Caldanaerobius polysaccharolyticus and identified a gene cluster encoding two glycoside hydrolase (GH) family 51 α-l-arabinofuranosidases (CpAbf51A, CpAbf51B), a GH43 endoarabinanase (CpAbn43A), a GH27 β-l-arabinopyranosidase (CpAbp27A), and two GH127 β-l-arabinofuranosidases (CpAbf127A, CpAbf127B). The genes were expressed as recombinant proteins, and the functions of the purified proteins were determined with para-nitrophenyl (pNP)-linked sugars and naturally occurring pectin structural elements as the substrates. The results demonstrated that CpAbn43A is an endoarabinanase while CpAbf51A and CpAbf51B are α-l-arabinofuranosidases that exhibit diverse substrate specificities, cleaving α-1,2, α-1,3, and α-1,5 linkages of purified arabinan-oligosaccharides. Furthermore, both CpAbf127A and CpAbf127B cleaved β-arabinofuranose residues in complex arabinan side chains, thus providing evidence of the function of this family of enzymes on such polysaccharides. The optimal temperatures of the enzymes ranged between 60°C and 75°C, and CpAbf43A and CpAbf51A worked synergistically to release arabinose from branched and debranched arabinan. Furthermore, the hydrolytic activity on branched arabinan oligosaccharides and degradation of pectic substrates by the endoarabinanase and l-arabinofuranosidases suggested a microbe equipped with diverse activities to degrade complex arabinan in the environment. Based on our functional analyses of the genes in the arabinan degradation cluster and the substrate-binding studies on a component of the cognate transporter system, we propose a model for arabinan degradation and transport by C. polysaccharolyticusIMPORTANCE Genomic DNA sequencing and bioinformatic analysis allowed the identification of a gene cluster encoding several proteins predicted to function in arabinan degradation and transport in C. polysaccharolyticus The analysis of the recombinant proteins yielded detailed insights into the putative arabinan metabolism of this thermophilic bacterium. The use of various branched arabinan oligosaccharides provided a detailed understanding of the substrate specificities of the enzymes and allowed assignment of two new GH127 polypeptides as β-l-arabinofuranosidases able to degrade pectic substrates, thus expanding our knowledge of this rare group of glycoside hydrolases. In addition, the enzymes showed synergistic effects for the degradation of arabinans at elevated temperatures. The enzymes characterized from the gene cluster are, therefore, of utility for arabinose production in both the biofuel and food industries.
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Mechelke M, Koeck DE, Broeker J, Roessler B, Krabichler F, Schwarz WH, Zverlov VV, Liebl W. Characterization of the arabinoxylan-degrading machinery of the thermophilic bacterium Herbinix hemicellulosilytica-Six new xylanases, three arabinofuranosidases and one xylosidase. J Biotechnol 2017; 257:122-130. [PMID: 28450260 DOI: 10.1016/j.jbiotec.2017.04.023] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Revised: 04/20/2017] [Accepted: 04/20/2017] [Indexed: 10/19/2022]
Abstract
Herbinix hemicellulosilytica is a newly isolated, gram-positive, anaerobic bacterium with extensive hemicellulose-degrading capabilities obtained from a thermophilic biogas reactor. In order to exploit its potential as a source for new industrial arabinoxylan-degrading enzymes, six new thermophilic xylanases, four from glycoside hydrolase family 10 (GH10) and two from GH11, three arabinofuranosidases (1x GH43, 2x GH51) and one β-xylosidase (GH43) were selected. The recombinantly produced enzymes were purified and characterized. All enzymes were active on different xylan-based polysaccharides and most of them showed temperature-vs-activity profiles with maxima around 55-65°C. HPAEC-PAD analysis of the hydrolysates of wheat arabinoxylan and of various purified xylooligosaccharides (XOS) and arabinoxylooligosaccharides (AXOS) was used to investigate their substrate and product specificities: among the GH10 xylanases, XynB showed a different product pattern when hydrolysing AXOS compared to XynA, XynC, and XynD. None of the GH11 xylanases was able to degrade any of the tested AXOS. All three arabinofuranosidases, ArfA, ArfB and ArfC, were classified as type AXH-m,d enzymes. None of the arabinofuranosidases was able to degrade the double-arabinosylated xylooligosaccharides XA2+3XX. β-Xylosidase XylA (GH43) was able to degrade unsubstituted XOS, but showed limited activity to degrade AXOS.
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Affiliation(s)
- M Mechelke
- Department of Microbiology, Technical University of Munich, Emil-Ramann-Str. 4, 85354 Freising-Weihenstephan, Germany
| | - D E Koeck
- Department of Microbiology, Technical University of Munich, Emil-Ramann-Str. 4, 85354 Freising-Weihenstephan, Germany
| | - J Broeker
- Department of Microbiology, Technical University of Munich, Emil-Ramann-Str. 4, 85354 Freising-Weihenstephan, Germany
| | - B Roessler
- Department of Microbiology, Technical University of Munich, Emil-Ramann-Str. 4, 85354 Freising-Weihenstephan, Germany
| | - F Krabichler
- Department of Microbiology, Technical University of Munich, Emil-Ramann-Str. 4, 85354 Freising-Weihenstephan, Germany
| | - W H Schwarz
- Department of Microbiology, Technical University of Munich, Emil-Ramann-Str. 4, 85354 Freising-Weihenstephan, Germany
| | - V V Zverlov
- Department of Microbiology, Technical University of Munich, Emil-Ramann-Str. 4, 85354 Freising-Weihenstephan, Germany; Institute of Molecular Genetics, Russian Academy of Science, Kurchatov Sq. 2, 123182 Moscow Russia
| | - W Liebl
- Department of Microbiology, Technical University of Munich, Emil-Ramann-Str. 4, 85354 Freising-Weihenstephan, Germany.
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Schendel RR, Puchbauer AK, Bunzel M. Glycoside Hydrolase Family 51 α-l-Arabinofuranosidases fromClostridium thermocellumandCellvibrio japonicusReleaseO–5-Feruloylated Arabinose. Cereal Chem 2016. [DOI: 10.1094/cchem-01-16-0011-n] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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
| | - 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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Synergistic degradation of arabinoxylan by free and immobilized xylanases and arabinofuranosidase. Biochem Eng J 2016. [DOI: 10.1016/j.bej.2016.07.013] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Koutaniemi S, Tenkanen M. Action of three GH51 and one GH54 α-arabinofuranosidases on internally and terminally located arabinofuranosyl branches. J Biotechnol 2016; 229:22-30. [DOI: 10.1016/j.jbiotec.2016.04.050] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Revised: 04/28/2016] [Accepted: 04/29/2016] [Indexed: 01/13/2023]
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Xie J, Zhao D, Zhao L, Pei J, Xiao W, Ding G, Wang Z, Xu J. Characterization of a novel arabinose-tolerant α
-l-
arabinofuranosidase with high ginsenoside Rc to ginsenoside Rd bioconversion productivity. J Appl Microbiol 2016; 120:647-60. [DOI: 10.1111/jam.13040] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2015] [Revised: 11/13/2015] [Accepted: 12/28/2015] [Indexed: 11/30/2022]
Affiliation(s)
- J. Xie
- College of Chemical Engineering; Nanjing Forestry University; Nanjing China
| | - D. Zhao
- College of Chemical Engineering; Nanjing Forestry University; Nanjing China
| | - L. Zhao
- College of Chemical Engineering; Nanjing Forestry University; Nanjing China
- Jiangsu Key Laboratory of Biomass Based Green Fuels and Chemicals; Nanjing China
| | - J. Pei
- College of Chemical Engineering; Nanjing Forestry University; Nanjing China
- Jiangsu Key Laboratory of Biomass Based Green Fuels and Chemicals; Nanjing China
| | - W. Xiao
- Jiangsu Kanion Pharmaceutical Co., Ltd.; Lianyungang China
| | - G. Ding
- Jiangsu Kanion Pharmaceutical Co., Ltd.; Lianyungang China
| | - Z. Wang
- Jiangsu Kanion Pharmaceutical Co., Ltd.; Lianyungang China
| | - J. Xu
- University of Massachusetts Lowell; Lowell MA USA
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Chlubnová I, Králová B, Dvořáková H, Spiwok V, Filipp D, Nugier-Chauvin C, Daniellou R, Ferrières V. Biocatalyzed synthesis of difuranosides and their ability to trigger production of TNF-α. Bioorg Med Chem Lett 2016; 26:1550-1553. [PMID: 26876932 DOI: 10.1016/j.bmcl.2016.02.018] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Revised: 02/05/2016] [Accepted: 02/07/2016] [Indexed: 10/22/2022]
Abstract
Transglycosylation reactions biocatalyzed by the native arabinofuranosidase Araf51 and using d-galactosyl, d-fucosyl and 6-deoxy-6-fluoro-D-galactosyl derivatives as donors and acceptors provided di-to pentahexofuranosides. The immunostimulatory potency of these compounds, and more especially their ability to induce production of TNF-α, was evaluated on the murine macrophage cell line, Raw 264.7. The results obtained showed concentration-dependent and most importantly, structure-dependent responses. Interestingly, oligoarabinofuranosides belonging to the oligopentafuranoside family displayed concentration-, chain length and aglycon-dependent bioactivities irrespective of their fine chemical variations. Thus, neo-oligofuranosides in D-Galf series, as well as their D-Fucf and 6-fluorinated counterparts are indeed potential sources of immunostimulating agents.
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Affiliation(s)
- Ilona Chlubnová
- Ecole Nationale Supérieure de Chimie de Rennes, CNRS, UMR 6226, 11 Allée de Beaulieu, CS 50837, 35708 Rennes Cedex 7, France; Université européenne de Bretagne, France; Department of Biochemistry and Microbiology, Institute of Chemical Technology of Prague, Techniká 3, 166 28 Prague 6, Czech Republic; Laboratory of Immunobiology, Institute of Molecular Genetics AS CR, Videnska 1083, 142 20 Prague 4, Czech Republic
| | - Blanka Králová
- Ecole Nationale Supérieure de Chimie de Rennes, CNRS, UMR 6226, 11 Allée de Beaulieu, CS 50837, 35708 Rennes Cedex 7, France; Department of Biochemistry and Microbiology, Institute of Chemical Technology of Prague, Techniká 3, 166 28 Prague 6, Czech Republic
| | - Hana Dvořáková
- Department of Biochemistry and Microbiology, Institute of Chemical Technology of Prague, Techniká 3, 166 28 Prague 6, Czech Republic; Laboratory of NMR Spectroscopy, Institute of Chemical Technology of Prague, Techniká 5, 166 28 Prague 6, Czech Republic
| | - Vojtěch Spiwok
- Department of Biochemistry and Microbiology, Institute of Chemical Technology of Prague, Techniká 3, 166 28 Prague 6, Czech Republic
| | - Dominik Filipp
- Laboratory of Immunobiology, Institute of Molecular Genetics AS CR, Videnska 1083, 142 20 Prague 4, Czech Republic
| | - Caroline Nugier-Chauvin
- Ecole Nationale Supérieure de Chimie de Rennes, CNRS, UMR 6226, 11 Allée de Beaulieu, CS 50837, 35708 Rennes Cedex 7, France; Université européenne de Bretagne, France
| | - Richard Daniellou
- Ecole Nationale Supérieure de Chimie de Rennes, CNRS, UMR 6226, 11 Allée de Beaulieu, CS 50837, 35708 Rennes Cedex 7, France; Université européenne de Bretagne, France
| | - Vincent Ferrières
- Ecole Nationale Supérieure de Chimie de Rennes, CNRS, UMR 6226, 11 Allée de Beaulieu, CS 50837, 35708 Rennes Cedex 7, France; Université européenne de Bretagne, France.
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Yang W, Bai Y, Yang P, Luo H, Huang H, Meng K, Shi P, Wang Y, Yao B. A novel bifunctional GH51 exo-α-l-arabinofuranosidase/endo-xylanase from Alicyclobacillus sp. A4 with significant biomass-degrading capacity. BIOTECHNOLOGY FOR BIOFUELS 2015; 8:197. [PMID: 26628911 PMCID: PMC4666033 DOI: 10.1186/s13068-015-0366-0] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2014] [Accepted: 10/27/2015] [Indexed: 05/11/2023]
Abstract
BACKGROUND Improving the hydrolytic performance of xylanolytic enzymes on arabinoxylan is of importance in the ethanol fermentation industry. Supplementation of debranching (arabinofuranosidase) and depolymerizing (xylanase) enzymes is a way to address the problem. In the present study, we identified a bifunctional α-l-arabinofuranosidase/endo-xylanase (Ac-Abf51A) of glycoside hydrolase family 51 in Alicyclobacillus sp. strain A4. Its biochemical stability and great hydrolysis efficiency against complex biomass make it a potential candidate for the production of biofuels. RESULTS The gene encoding Ac-Abf51A was cloned. The comparison of its sequence with reference proteins having resolved 3D-structures revealed nine key residues involved in catalysis and substrate-binding interaction. Recombinant Ac-Abf51A produced in Escherichia coli showed optimal activity at pH 6.0 and 60 °C with 4-nitrophenyl-α-l-arabinofuranoside as the substrate. The enzyme exhibited an exo-type mode of action on polyarabinosides by catalyzing the cleavage of α-1,2- and α-1,3-linked arabinofuranose side chains in sugar beet arabinan and water-soluble wheat arabinoxylan and α-1,5-linked arabinofuranosidic bonds in debranched sugar beet arabinan. Surprisingly, it had capacity to release xylobiose and xylotriose from wheat arabinoxylan and was active on xylooligosaccharides (xylohexaose 1.2/mM/min, xylopentaose 6.9/mM/min, and xylotetraose 19.7/mM/min), however a lower level of activity. Moreover, Ac-Abf51A showed greater synergistic effect in combination with xylanase (2.92-fold) on wheat arabinoxylan degradation than other reported enzymes, for the amounts of arabinose, xylose, and xylobiose were all increased in comparison to that by the enzymes acting individually. CONCLUSIONS This study for the first time reports a GH51 enzyme with both exo-α-l-arabinofuranosidase and endo-xylanase activities. It was stable over a broad pH range and at high temperature, and showed greater synergistic effect with xylanase on the degradation of wheat arabinoxylan than other counterparts. The distinguished synergy might be ascribed to its bifunctional α-l-arabinofuranosidase/xylanase activity, which may represent a possible way to degrade biomass at lower enzyme loadings.
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Affiliation(s)
- Wenxia Yang
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, No. 12 Zhongguancun South Street, Beijing, 100081 People’s Republic of China
| | - Yingguo Bai
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, No. 12 Zhongguancun South Street, Beijing, 100081 People’s Republic of China
| | - Peilong Yang
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, No. 12 Zhongguancun South Street, Beijing, 100081 People’s Republic of China
| | - Huiying Luo
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, No. 12 Zhongguancun South Street, Beijing, 100081 People’s Republic of China
| | - Huoqing Huang
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, No. 12 Zhongguancun South Street, Beijing, 100081 People’s Republic of China
| | - Kun Meng
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, No. 12 Zhongguancun South Street, Beijing, 100081 People’s Republic of China
| | - Pengjun Shi
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, No. 12 Zhongguancun South Street, Beijing, 100081 People’s Republic of China
| | - Yaru Wang
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, No. 12 Zhongguancun South Street, Beijing, 100081 People’s Republic of China
| | - Bin Yao
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, No. 12 Zhongguancun South Street, Beijing, 100081 People’s Republic of China
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Mendis M, Leclerc E, Simsek S. Arabinoxylans, gut microbiota and immunity. Carbohydr Polym 2015; 139:159-66. [PMID: 26794959 DOI: 10.1016/j.carbpol.2015.11.068] [Citation(s) in RCA: 102] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2015] [Revised: 10/28/2015] [Accepted: 11/26/2015] [Indexed: 01/12/2023]
Abstract
Arabinoxylan (AX) is a non-starch polysaccharide found in many cereal grains and is considered as a dietary fiber. Despite their general structure, there is structural heterogeneity among AX originating from different botanical sources. Furthermore, the extraction procedure and hydrolysis by xylolytic enzymes can further render differences to theses AX. The aim of this review was to address the effects of AX on the gut bacteria and their immunomodulatory properties. Given the complex structure of AX, we also aimed to discuss how the structural heterogeneity of AX affects its role in bacterial growth and immunomodulation. The existing literature indicates the role of fine structural details of AX on its potential as polysaccharides that can impact the gut associated microbial growth and immune system.
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Affiliation(s)
- Mihiri Mendis
- North Dakota State University, Department of Plant Sciences, Cereal Science Graduate Program, Fargo, ND, USA
| | - Estelle Leclerc
- North Dakota State University, Department of Pharmaceutical Sciences, College of Health Professions, Fargo, ND, USA
| | - Senay Simsek
- North Dakota State University, Department of Plant Sciences, Cereal Science Graduate Program, Fargo, ND, USA.
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Production of structurally diverse wheat arabinoxylan hydrolyzates using combinations of xylanase and arabinofuranosidase. Carbohydr Polym 2015; 132:452-9. [DOI: 10.1016/j.carbpol.2015.05.083] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2015] [Revised: 05/08/2015] [Accepted: 05/17/2015] [Indexed: 11/17/2022]
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Abstract
SUMMARY Biomass is constructed of dense recalcitrant polymeric materials: proteins, lignin, and holocellulose, a fraction constituting fibrous cellulose wrapped in hemicellulose-pectin. Bacteria and fungi are abundant in soil and forest floors, actively recycling biomass mainly by extracting sugars from holocellulose degradation. Here we review the genome-wide contents of seven Aspergillus species and unravel hundreds of gene models encoding holocellulose-degrading enzymes. Numerous apparent gene duplications followed functional evolution, grouping similar genes into smaller coherent functional families according to specialized structural features, domain organization, biochemical activity, and genus genome distribution. Aspergilli contain about 37 cellulase gene models, clustered in two mechanistic categories: 27 hydrolyze and 10 oxidize glycosidic bonds. Within the oxidative enzymes, we found two cellobiose dehydrogenases that produce oxygen radicals utilized by eight lytic polysaccharide monooxygenases that oxidize glycosidic linkages, breaking crystalline cellulose chains and making them accessible to hydrolytic enzymes. Among the hydrolases, six cellobiohydrolases with a tunnel-like structural fold embrace single crystalline cellulose chains and cooperate at nonreducing or reducing end termini, splitting off cellobiose. Five endoglucanases group into four structural families and interact randomly and internally with cellulose through an open cleft catalytic domain, and finally, seven extracellular β-glucosidases cleave cellobiose and related oligomers into glucose. Aspergilli contain, on average, 30 hemicellulase and 7 accessory gene models, distributed among 9 distinct functional categories: the backbone-attacking enzymes xylanase, mannosidase, arabinase, and xyloglucanase, the short-side-chain-removing enzymes xylan α-1,2-glucuronidase, arabinofuranosidase, and xylosidase, and the accessory enzymes acetyl xylan and feruloyl esterases.
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Kozlova LV, Gorshkov OV, Mokshina NE, Gorshkova TA. Differential expression of α-L-arabinofuranosidases during maize (Zea mays L.) root elongation. PLANTA 2015; 241:1159-1172. [PMID: 25608890 DOI: 10.1007/s00425-015-2244-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Accepted: 01/08/2015] [Indexed: 06/04/2023]
Abstract
Specific α- l -arabinofuranosidases are involved in the realisation of elongation growth process in cells with type II cell walls. Elongation growth in a plant cell is largely based on modification of the cell wall. In type II cell walls, the Ara/Xyl ratio is known to decrease during elongation due to the partial removal of Ara residues from glucuronoarabinoxylan. We searched within the maize genome for the genes of all predicted α-L-arabinofuranosidases that may be responsible for such a process and related their expression to the activity of the enzyme and the amount of free arabinose measured in six zones of a growing maize root. Eight genes of the GH51 family (ZmaABFs) and one gene of the GH3 family (ZmaARA-I) were identified. The abundance of ZmaABF1 and 3-6 transcripts was highly correlated with the measured enzymatic activity and free arabinose content that significantly increased during elongation. The transcript abundances also coincided with the pattern of changes in the Ara/Xyl ratio of the xylanase-extractable glucuronoarabinoxylan described in previous studies. The expression of ZmaABF3, 5 and 6 was especially up-regulated during elongation although corresponding proteins are devoid of the catalytic glutamate at the proper position. ZmaABF2 transcripts were specifically enriched in the root cap and meristem. A single ZmaARA-I gene was not expressed as a whole gene but instead as splice variants that encode the C-terminal end of the protein. Changes in the ZmaARA-I transcript level were rather moderate and had no significant correlation with free arabinose content. Thus, elongation growth of cells with type II cell walls is accompanied by the up-regulation of specific and predicted α-L-arabinofuranosidase genes, and the corresponding activity is indeed pronounced and is important for the modification of glucuronoarabinoxylan, which plays a key role in the modification of the cell wall supramolecular organisation.
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Affiliation(s)
- Liudmila V Kozlova
- Kazan Scientific Center, Kazan Institute of Biochemistry and Biophysics, Russian Academy of Sciences, Lobachevsky 2/31, p.o. 30, 420111, Kazan, Russia,
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Pennec A, Daniellou R, Loyer P, Nugier-Chauvin C, Ferrières V. Araf51 with improved transglycosylation activities: one engineered biocatalyst for one specific acceptor. Carbohydr Res 2015; 402:50-5. [DOI: 10.1016/j.carres.2014.10.031] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2014] [Revised: 10/10/2014] [Accepted: 10/31/2014] [Indexed: 10/24/2022]
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Sawhney N, Preston JF. GH51 arabinofuranosidase and its role in the methylglucuronoarabinoxylan utilization system in Paenibacillus sp. strain JDR-2. Appl Environ Microbiol 2014; 80:6114-25. [PMID: 25063665 PMCID: PMC4178703 DOI: 10.1128/aem.01684-14] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2014] [Accepted: 07/22/2014] [Indexed: 11/20/2022] Open
Abstract
Methylglucuronoarabinoxylan (MeGAXn) from agricultural residues and energy crops is a significant yet underutilized biomass resource for production of biofuels and chemicals. Mild thermochemical pretreatment of bagasse yields MeGAXn requiring saccharifying enzymes for conversion to fermentable sugars. A xylanolytic bacterium, Paenibacillus sp. strain JDR-2, produces an extracellular cell-associated GH10 endoxylanse (XynA1) which efficiently depolymerizes methylglucuronoxylan (MeGXn) from hardwoods coupled with assimilation of oligosaccharides for further processing by intracellular GH67 α-glucuronidase, GH10 endoxylanase, and GH43 β-xylosidase. This process has been ascribed to genes that comprise a xylan utilization regulon that encodes XynA1 and includes a gene cluster encoding transcriptional regulators, ABC transporters, and intracellular enzymes that convert assimilated oligosaccharides to fermentable sugars. Here we show that Paenibacillus sp. JDR-2 utilized MeGAXn without accumulation of oligosaccharides in the medium. The Paenibacillus sp. JDR-2 growth rate on MeGAXn was 3.1-fold greater than that on oligosaccharides generated from MeGAXn by XynA1. Candidate genes encoding GH51 arabinofuranosidases with potential roles were identified. Following growth on MeGAXn, quantitative reverse transcription-PCR identified a cluster of genes encoding a GH51 arabinofuranosidase (AbfB) and transcriptional regulators which were coordinately expressed along with the genes comprising the xylan utilization regulon. The action of XynA1 on MeGAXn generated arabinoxylobiose, arabinoxylotriose, xylobiose, xylotriose, and methylglucuronoxylotriose. Recombinant AbfB processed arabinoxylooligosaccharides to xylooligosaccharides and arabinose. MeGAXn processing by Paenibacillus sp. JDR-2 may be achieved by extracellular depolymerization by XynA1 coupled to assimilation of oligosaccharides and further processing by intracellular enzymes, including AbfB. Paenibacillus sp. JDR-2 provides a GH10/GH67 system complemented with genes encoding intracellular GH51 arabinofuranosidases for efficient utilization of MeGAXn.
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Affiliation(s)
- Neha Sawhney
- Department of Microbiology and Cell Science, University of Florida, Gainesville, Florida, USA
| | - James F Preston
- Department of Microbiology and Cell Science, University of Florida, Gainesville, Florida, USA
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Elucidation of the molecular basis for arabinoxylan-debranching activity of a thermostable family GH62 α-l-arabinofuranosidase from Streptomyces thermoviolaceus. Appl Environ Microbiol 2014; 80:5317-29. [PMID: 24951792 DOI: 10.1128/aem.00685-14] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Xylan-debranching enzymes facilitate the complete hydrolysis of xylan and can be used to alter xylan chemistry. Here, the family GH62 α-l-arabinofuranosidase from Streptomyces thermoviolaceus (SthAbf62A) was shown to have a half-life of 60 min at 60°C and the ability to cleave α-1,3 l-arabinofuranose (l-Araf) from singly substituted xylopyranosyl (Xylp) backbone residues in wheat arabinoxylan; low levels of activity on arabinan as well as 4-nitrophenyl α-l-arabinofuranoside were also detected. After selective removal of α-1,3 l-Araf substituents from disubstituted Xylp residues present in wheat arabinoxylan, SthAbf62A could also cleave the remaining α-1,2 l-Araf substituents, confirming the ability of SthAbf62A to remove α-l-Araf residues that are (1→2) and (1→3) linked to monosubstituted β-d-Xylp sugars. Three-dimensional structures of SthAbf62A and its complex with xylotetraose and l-arabinose confirmed a five-bladed β-propeller fold and revealed a molecular Velcro in blade V between the β1 and β21 strands, a disulfide bond between Cys27 and Cys297, and a calcium ion coordinated in the central channel of the fold. The enzyme-arabinose complex structure further revealed a narrow and seemingly rigid l-arabinose binding pocket situated at the center of one side of the β propeller, which stabilized the arabinofuranosyl substituent through several hydrogen-bonding and hydrophobic interactions. The predicted catalytic amino acids were oriented toward this binding pocket, and the catalytic essentiality of Asp53 and Glu213 was confirmed by site-specific mutagenesis. Complex structures with xylotetraose revealed a shallow cleft for xylan backbone binding that is open at both ends and comprises multiple binding subsites above and flanking the l-arabinose binding pocket.
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Chlubnová I, Králová B, Dvořáková H, Hošek P, Spiwok V, Filipp D, Nugier-Chauvin C, Daniellou R, Ferrières V. The versatile enzyme Araf51 allowed efficient synthesis of rare pathogen-related β-d-galactofuranosyl-pyranoside disaccharides. Org Biomol Chem 2014; 12:3080-9. [DOI: 10.1039/c3ob42519c] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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β-xylosidases and α-L-arabinofuranosidases: accessory enzymes for arabinoxylan degradation. Biotechnol Adv 2013; 32:316-32. [PMID: 24239877 DOI: 10.1016/j.biotechadv.2013.11.005] [Citation(s) in RCA: 102] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2013] [Revised: 10/28/2013] [Accepted: 11/09/2013] [Indexed: 11/22/2022]
Abstract
Arabinoxylan (AX) is among the most abundant hemicelluloses on earth and one of the major components of feedstocks that are currently investigated as a source for advanced biofuels. As global research into these sustainable biofuels is increasing, scientific knowledge about the enzymatic breakdown of AX advanced significantly over the last decade. This review focuses on the exo-acting AX hydrolases, such as α-arabinofuranosidases and β-xylosidases. It aims to provide a comprehensive overview of the diverse substrate specificities and corresponding structural features found in the different glycoside hydrolase families. A careful review of the available literature reveals a marked difference in activity between synthetically labeled and naturally occurring substrates, often leading to erroneous enzymatic annotations. Therefore, special attention is given to enzymes with experimental evidence on the hydrolysis of natural polymers.
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Ahmed S, Luis AS, Bras JLA, Ghosh A, Gautam S, Gupta MN, Fontes CMGA, Goyal A. A novel α-L-arabinofuranosidase of family 43 glycoside hydrolase (Ct43Araf) from Clostridium thermocellum. PLoS One 2013; 8:e73575. [PMID: 24039988 PMCID: PMC3767815 DOI: 10.1371/journal.pone.0073575] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2013] [Accepted: 07/27/2013] [Indexed: 11/25/2022] Open
Abstract
The study describes a comparative analysis of biochemical, structural and functional properties of two recombinant derivatives from Clostridium thermocellum ATCC 27405 belonging to family 43 glycoside hydrolase. The family 43 glycoside hydrolase encoding α-L-arabinofuranosidase (Ct43Araf) displayed an N-terminal catalytic module CtGH43 (903 bp) followed by two carbohydrate binding modules CtCBM6A (405 bp) and CtCBM6B (402 bp) towards the C-terminal. Ct43Araf and its truncated derivative CtGH43 were cloned in pET-vectors, expressed in Escherichia coli and functionally characterized. The recombinant proteins displayed molecular sizes of 63 kDa (Ct43Araf) and 34 kDa (CtGH43) on SDS-PAGE analysis. Ct43Araf and CtGH43 showed optimal enzyme activities at pH 5.7 and 5.4 and the optimal temperature for both was 50°C. Ct43Araf and CtGH43 showed maximum activity with rye arabinoxylan 4.7 Umg(-1) and 5.0 Umg(-1), respectively, which increased by more than 2-fold in presence of Ca(2+) and Mg(2+) salts. This indicated that the presence of CBMs (CtCBM6A and CtCBM6B) did not have any effect on the enzyme activity. The thin layer chromatography and high pressure anion exchange chromatography analysis of Ct43Araf hydrolysed arabinoxylans (rye and wheat) and oat spelt xylan confirmed the release of L-arabinose. This is the first report of α-L-arabinofuranosidase from C. thermocellum having the capacity to degrade both p-nitrophenol-α-L-arabinofuranoside and p-nitrophenol-α-L-arabinopyranoside. The protein melting curves of Ct43Araf and CtGH43 demonstrated that CtGH43 and CBMs melt independently. The presence of Ca(2+) ions imparted thermal stability to both the enzymes. The circular dichroism analysis of CtGH43 showed 48% β-sheets, 49% random coils but only 3% α-helices.
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Affiliation(s)
- Shadab Ahmed
- Department of Biotechnology, Indian Institute of Technology Guwahati, Guwahati, Assam, India
| | - Ana Sofia Luis
- CIISA-Faculdade de MedicinaVeterinaria, Avenida da Universidade Técnica, Lisbon, Portugal
| | - Joana L. A. Bras
- CIISA-Faculdade de MedicinaVeterinaria, Avenida da Universidade Técnica, Lisbon, Portugal
| | - Arabinda Ghosh
- Department of Biotechnology, Indian Institute of Technology Guwahati, Guwahati, Assam, India
| | - Saurabh Gautam
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi, India
| | - Munishwar N. Gupta
- Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi, India
| | - Carlos M. G. A. Fontes
- CIISA-Faculdade de MedicinaVeterinaria, Avenida da Universidade Técnica, Lisbon, Portugal
| | - Arun Goyal
- Department of Biotechnology, Indian Institute of Technology Guwahati, Guwahati, Assam, India
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Characterization of a Hexameric Exo-Acting GH51 α-l-Arabinofuranosidase from the Mesophilic Bacillus subtilis. Mol Biotechnol 2013; 55:260-7. [DOI: 10.1007/s12033-013-9677-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Reconstitution of a thermostable xylan-degrading enzyme mixture from the bacterium Caldicellulosiruptor bescii. Appl Environ Microbiol 2012; 79:1481-90. [PMID: 23263957 DOI: 10.1128/aem.03265-12] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Xylose, the major constituent of xylans, as well as the side chain sugars, such as arabinose, can be metabolized by engineered yeasts into ethanol. Therefore, xylan-degrading enzymes that efficiently hydrolyze xylans will add value to cellulases used in hydrolysis of plant cell wall polysaccharides for conversion to biofuels. Heterogeneous xylan is a complex substrate, and it requires multiple enzymes to release its constituent sugars. However, the components of xylan-degrading enzymes are often individually characterized, leading to a dearth of research that analyzes synergistic actions of the components of xylan-degrading enzymes. In the present report, six genes predicted to encode components of the xylan-degrading enzymes of the thermophilic bacterium Caldicellulosiruptor bescii were expressed in Escherichia coli, and the recombinant proteins were investigated as individual enzymes and also as a xylan-degrading enzyme cocktail. Most of the component enzymes of the xylan-degrading enzyme mixture had similar optimal pH (5.5 to ∼6.5) and temperature (75 to ∼90°C), and this facilitated their investigation as an enzyme cocktail for deconstruction of xylans. The core enzymes (two endoxylanases and a β-xylosidase) exhibited high turnover numbers during catalysis, with the two endoxylanases yielding estimated k(cat) values of ∼8,000 and ∼4,500 s(-1), respectively, on soluble wheat arabinoxylan. Addition of side chain-cleaving enzymes to the core enzymes increased depolymerization of a more complex model substrate, oat spelt xylan. The C. bescii xylan-degrading enzyme mixture effectively hydrolyzes xylan at 65 to 80°C and can serve as a basal mixture for deconstruction of xylans in bioenergy feedstock at high temperatures.
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Zawaira A, Shibayama Y. A simple recipe for the non-expert bioinformaticist for building experimentally-testable hypotheses for proteins with no known homologs. JOURNAL OF STRUCTURAL AND FUNCTIONAL GENOMICS 2012; 13:185-200. [PMID: 22956349 DOI: 10.1007/s10969-012-9141-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/29/2012] [Accepted: 08/08/2012] [Indexed: 06/01/2023]
Abstract
The study of the protein-protein interactions (PPIs) of unique ORFs is a strategy for deciphering the biological roles of unique ORFs of interest. For uniform reference, we define unique ORFs as those for which no matching protein is found after PDB-BLAST search with default parameters. The uniqueness of the ORFs generally precludes the straightforward use of structure-based approaches in the design of experiments to explore PPIs. Many open-source bioinformatics tools, from the commonly-used to the relatively esoteric, have been built and validated to perform analyses and/or predictions of sorts on proteins. How can these available tools be combined into a protocol that helps the non-expert bioinformaticist researcher to design experiments to explore the PPIs of their unique ORF? Here we define a pragmatic protocol based on accessibility of software to achieve this and we make it concrete by applying it on two proteins-the ImuB and ImuA' proteins from Mycobacterium tuberculosis. The protocol is pragmatic in that decisions are made largely based on the availability of easy-to-use freeware. We define the following basic and user-friendly software pathway to build testable PPI hypotheses for a query protein sequence: PSI-PRED → MUSTER → metaPPISP → ASAView and ConSurf. Where possible, other analytical and/or predictive tools may be included. Our protocol combines the software predictions and analyses with general bioinformatics principles to arrive at consensus, prioritised and testable PPI hypotheses.
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Affiliation(s)
- Alexander Zawaira
- Gene Expression and Biophysics Group, Synthetic Biology, ERA, CSIR Biosciences, Brummeria, Pretoria, South Africa.
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