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Yan R, Wang W, Vuong TV, Xiu Y, Skarina T, Di Leo R, Gatenholm P, Toriz G, Tenkanen M, Stogios PJ, Master ER. Structural characterization of the family GH115 α-glucuronidase from Amphibacillus xylanus yields insight into its coordinated action with α-arabinofuranosidases. N Biotechnol 2021; 62:49-56. [PMID: 33486119 DOI: 10.1016/j.nbt.2021.01.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Revised: 01/11/2021] [Accepted: 01/16/2021] [Indexed: 01/01/2023]
Abstract
The coordinated action of carbohydrate-active enzymes has mainly been evaluated for the purpose of complete saccharification of plant biomass (lignocellulose) to sugars. By contrast, the coordinated action of accessory hemicellulases on xylan debranching and recovery is less well characterized. Here, the activity of two family GH115 α-glucuronidases (SdeAgu115A from Saccharophagus degradans, and AxyAgu115A from Amphibacillus xylanus) on spruce arabinoglucuronoxylan (AGX) was evaluated in combination with an α-arabinofuranosidase from families GH51 (AniAbf51A, aka E-AFASE from Aspergillus niger) and GH62 (SthAbf62A from Streptomyces thermoviolaceus). The α-arabinofuranosidases boosted (methyl)-glucuronic acid release by SdeAgu115A by approximately 50 % and 30 %, respectively. The impact of the α-arabinofuranosidases on AxyAgu115A activity was comparatively low, motivating its structural characterization. The crystal structure of AxyAgu115A revealed increased length and flexibility of the active site loop compared to SdeAgu115A. This structural difference could explain the ability of AxyAgu115A to accommodate more highly substituted arabinoglucuronoxylan, and inform enzyme selections for improved AGX recovery and use.
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Affiliation(s)
- Ruoyu Yan
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, 200 College Street, Toronto, Ontario, M5S 3E5, Canada
| | - Weijun Wang
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, 200 College Street, Toronto, Ontario, M5S 3E5, Canada
| | - Thu V Vuong
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, 200 College Street, Toronto, Ontario, M5S 3E5, Canada
| | - Yang Xiu
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, 200 College Street, Toronto, Ontario, M5S 3E5, Canada
| | - Tatiana Skarina
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, 200 College Street, Toronto, Ontario, M5S 3E5, Canada
| | - Rosa Di Leo
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, 200 College Street, Toronto, Ontario, M5S 3E5, Canada
| | - Paul Gatenholm
- Department of Chemistry and Chemical Engineering, Wallenberg Wood Science Center and Biopolymer Technology, Chalmers University of Technology, Kemivägen 4, Gothenburg, 412 96, Sweden
| | - Guillermo Toriz
- Department of Wood, Cellulose and Paper Research, University of Guadalajara, Guadalajara, 44100, Mexico
| | - Maija Tenkanen
- Department of Food and Environmental Sciences, University of Helsinki, P.O. Box 27, Helsinki, 00014, Finland
| | - Peter J Stogios
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, 200 College Street, Toronto, Ontario, M5S 3E5, Canada
| | - Emma R Master
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, 200 College Street, Toronto, Ontario, M5S 3E5, Canada; Department of Bioproducts and Biosystems, Aalto University, FI-00076, Aalto, Kemistintie 1, Espoo, Finland.
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Ke Y, Yuan X, Li J, Zhou W, Huang X, Wang T. High-level expression, purification, and enzymatic characterization of a recombinant Aspergillus sojae alkaline protease in Pichia pastoris. Protein Expr Purif 2018; 148:24-29. [PMID: 29596989 DOI: 10.1016/j.pep.2018.03.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Revised: 02/28/2018] [Accepted: 03/23/2018] [Indexed: 11/18/2022]
Abstract
An alkaline protease (Ap) was cloned from Aspergillus sojae GIM3.33 via RT-PCR technique. A truncated Ap without the signal peptide was successfully expressed in the Pichia pastoris KM71 strain. The following describes the optimal process conditions for the recombinant engineering of a strain expressing a recombinant Ap (rAp) in a triangular flask: inoculum concentration OD600 value 20.0 in 40 mL working volume (in 500 mL flasks), methanol addition (1.0%; volume ratio), 0.02% biotin solution (60 μL), and YNB primary concentration (13.0 g/L). Under these conditions, the protease activity of rAp in the fermentation broth reached 400.4 ± 40.5 U/mL after induction for three days. The rAp was isolated and purified, and its enzymatic characteristics were tested. Its optimal pH was 10.0, and it remained stable in a pH range of 7.0-10.0. Its optimal temperature was 45 °C and it retained >50% activity at 40 °C for 60 min. The rAp activity was significantly inhibited by PMSF, Zn2+ and Fe2+ and the rAp had a broad substrate specificity for natural proteins and synthetic peptide substrates, and preferred substrates at P1 position with large hydrophobic side-chain groups. Compared to Papain (8.7%) and Alcalase (12.2%), the degree of hydrolysis of rAp to soy protein isolate was 16.5%; therefore, rAp was a good candidate for the processing of food industry byproducts.
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Affiliation(s)
- Ye Ke
- School of Life Sciences, Shaoguan University, Shaoguan, Guangdong, 512005, People's Republic of China.
| | - XiaoMei Yuan
- School of Life Sciences, Shaoguan University, Shaoguan, Guangdong, 512005, People's Republic of China.
| | - JiaSheng Li
- School of Life Sciences, Shaoguan University, Shaoguan, Guangdong, 512005, People's Republic of China.
| | - Wei Zhou
- School of Life Sciences, Shaoguan University, Shaoguan, Guangdong, 512005, People's Republic of China.
| | - XiaoHui Huang
- School of Life Sciences, Shaoguan University, Shaoguan, Guangdong, 512005, People's Republic of China.
| | - Tao Wang
- School of Life Sciences, Shaoguan University, Shaoguan, Guangdong, 512005, People's Republic of China.
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GH62 arabinofuranosidases: Structure, function and applications. Biotechnol Adv 2017; 35:792-804. [DOI: 10.1016/j.biotechadv.2017.06.005] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Revised: 06/17/2017] [Accepted: 06/23/2017] [Indexed: 01/03/2023]
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Wilkens C, Andersen S, Petersen BO, Li A, Busse-Wicher M, Birch J, Cockburn D, Nakai H, Christensen HEM, Kragelund BB, Dupree P, McCleary B, Hindsgaul O, Hachem MA, Svensson B. An efficient arabinoxylan-debranching α-l-arabinofuranosidase of family GH62 from Aspergillus nidulans contains a secondary carbohydrate binding site. Appl Microbiol Biotechnol 2016; 100:6265-6277. [DOI: 10.1007/s00253-016-7417-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2015] [Revised: 02/07/2016] [Accepted: 02/22/2016] [Indexed: 10/22/2022]
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Kaur AP, Nocek BP, Xu X, Lowden MJ, Leyva JF, Stogios PJ, Cui H, Di Leo R, Powlowski J, Tsang A, Savchenko A. Functional and structural diversity in GH62 α-L-arabinofuranosidases from the thermophilic fungus Scytalidium thermophilum. Microb Biotechnol 2014; 8:419-33. [PMID: 25267315 PMCID: PMC4408175 DOI: 10.1111/1751-7915.12168] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2014] [Accepted: 08/16/2014] [Indexed: 01/22/2023] Open
Abstract
The genome of the thermophilic fungus Scytalidium thermophilum (strain CBS 625.91) harbours a wide range of genes involved in carbohydrate degradation, including three genes, abf62A, abf62B and abf62C, predicted to encode glycoside hydrolase family 62 (GH62) enzymes. Transcriptome analysis showed that only abf62A and abf62C are actively expressed during growth on diverse substrates including straws from barley, alfalfa, triticale and canola. The abf62A and abf62C genes were expressed in Escherichia coli and the resulting recombinant proteins were characterized. Calcium-free crystal structures of Abf62C in apo and xylotriose bound forms were determined to 1.23 and 1.48 Å resolution respectively. Site-directed mutagenesis confirmed Asp55, Asp171 and Glu230 as catalytic triad residues, and revealed the critical role of non-catalytic residues Asp194, Trp229 and Tyr338 in positioning the scissile α-L-arabinofuranoside bond at the catalytic site. Further, the +2R substrate-binding site residues Tyr168 and Asn339, as well as the +2NR residue Tyr226, are involved in accommodating long-chain xylan polymers. Overall, our structural and functional analysis highlights characteristic differences between Abf62A and Abf62C, which represent divergent subgroups in the GH62 family.
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Affiliation(s)
- Amrit Pal Kaur
- Department of Chemical Engineering and Applied Chemistry, University of Toronto, ON, M5S 3E5, Canada
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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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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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De La Mare M, Guais O, Bonnin E, Weber J, Francois JM. Molecular and biochemical characterization of three GH62 α-l-arabinofuranosidases from the soil deuteromycete Penicillium funiculosum. Enzyme Microb Technol 2013; 53:351-8. [DOI: 10.1016/j.enzmictec.2013.07.008] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2013] [Revised: 07/29/2013] [Accepted: 07/31/2013] [Indexed: 01/17/2023]
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Chlubnova I, Legentil L, Dureau R, Pennec A, Almendros M, Daniellou R, Nugier-Chauvin C, Ferrières V. Specific and non-specific enzymes for furanosyl-containing conjugates: biosynthesis, metabolism, and chemo-enzymatic synthesis. Carbohydr Res 2012; 356:44-61. [PMID: 22554502 DOI: 10.1016/j.carres.2012.04.002] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2012] [Revised: 04/02/2012] [Accepted: 04/03/2012] [Indexed: 11/27/2022]
Abstract
There is no doubt now that the synthesis of compounds of varying complexity such as saccharides and derivatives thereof continuously grows with enzymatic methods. This review focuses on recent basic knowledge on enzymes specifically involved in the biosynthesis and degradation of furanosyl-containing polysaccharides and conjugates. Moreover, and when possible, biocatalyzed approaches, alternative to standard synthesis, will be detailed in order to strengthen the high potential of these biocatalysts to go further with the preparation of rare furanosides. Interesting results will be also proposed with chemo-enzymatic processes based on nonfuranosyl-specific enzymes.
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Affiliation(s)
- Ilona Chlubnova
- Ecole Nationale Supérieure de Chimie de Rennes, CNRS, UMR 6226, Avenue du Général Leclerc, CS 50837, 35708 Rennes Cedex 7, France
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Lee DS, Wi SG, Lee YG, Cho EJ, Chung BY, Bae HJ. Characterization of a New α-l-Arabinofuranosidase from Penicillium sp. LYG 0704, and their Application in Lignocelluloses Degradation. Mol Biotechnol 2011; 49:229-39. [DOI: 10.1007/s12033-011-9396-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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11
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Seiboth B, Metz B. Fungal arabinan and L-arabinose metabolism. Appl Microbiol Biotechnol 2011; 89:1665-73. [PMID: 21212945 PMCID: PMC3044236 DOI: 10.1007/s00253-010-3071-8] [Citation(s) in RCA: 95] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2010] [Revised: 12/08/2010] [Accepted: 12/08/2010] [Indexed: 12/04/2022]
Abstract
l-Arabinose is the second most abundant pentose beside d-xylose and is found in the plant polysaccharides, hemicellulose and pectin. The need to find renewable carbon and energy sources has accelerated research to investigate the potential of l-arabinose for the development and production of biofuels and other bioproducts. Fungi produce a number of extracellular arabinanases, including α-l-arabinofuranosidases and endo-arabinanases, to specifically release l-arabinose from the plant polymers. Following uptake of l-arabinose, its intracellular catabolism follows a four-step alternating reduction and oxidation path, which is concluded by a phosphorylation, resulting in d-xylulose 5-phosphate, an intermediate of the pentose phosphate pathway. The genes and encoding enzymes l-arabinose reductase, l-arabinitol dehydrogenase, l-xylulose reductase, xylitol dehydrogenase, and xylulokinase of this pathway were mainly characterized in the two biotechnological important fungi Aspergillus niger and Trichoderma reesei. Analysis of the components of the l-arabinose pathway revealed a number of specific adaptations in the enzymatic and regulatory machinery towards the utilization of l-arabinose. Further genetic and biochemical analysis provided evidence that l-arabinose and the interconnected d-xylose pathway are also involved in the oxidoreductive degradation of the hexose d-galactose.
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Affiliation(s)
- Bernhard Seiboth
- Research Area Gene Technology and Applied Biochemistry, Institute of Chemical Engineering, Vienna University of Technology, Wien, Austria.
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Identification of a GH62 α-l-arabinofuranosidase specific for arabinoxylan produced by Penicillium chrysogenum. Appl Microbiol Biotechnol 2010; 90:137-46. [DOI: 10.1007/s00253-010-2988-2] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2010] [Revised: 10/25/2010] [Accepted: 10/25/2010] [Indexed: 01/13/2023]
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13
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Lim YR, Yoon RY, Seo ES, Kim YS, Park CS, Oh DK. Hydrolytic properties of a thermostable α-l-arabinofuranosidase from Caldicellulosiruptor saccharolyticus. J Appl Microbiol 2010; 109:1188-97. [DOI: 10.1111/j.1365-2672.2010.04744.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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14
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Numan MT, Bhosle NB. Alpha-L-arabinofuranosidases: the potential applications in biotechnology. J Ind Microbiol Biotechnol 2005; 33:247-60. [PMID: 16385399 DOI: 10.1007/s10295-005-0072-1] [Citation(s) in RCA: 111] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2005] [Accepted: 12/13/2005] [Indexed: 10/25/2022]
Abstract
Recently, alpha-L-arabinofuranosidases (EC3.2.1.55) have received increased attention primarily due to their role in the degradation of lignocelluloses as well as their positive effect on the activity of other enzymes acting on lignocelluloses. As a result, these enzymes are used in many biotechnological applications including wine industry, clarification of fruit juices, digestion enhancement of animal feedstuffs and as a natural improver for bread. Moreover, these enzymes could be used to improve existing technologies and to develop new technologies. The production, mechanisms of action, classification, synergistic role, biochemical properties, substrate specificities, molecular biology and biotechnological applications of these enzymes have been reviewed in this article.
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Affiliation(s)
- Mondher Th Numan
- National Institute Of Oceanography, 403004 Dona Poula, Goa, India.
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Oshima H, Kimura I, Kimura Y, Tajima S, Izumori K. Purification and Characterization of an Exo-1,5-.ALPHA.-L-Arabinanase from Aspergillus sojae. J Appl Glycosci (1999) 2005. [DOI: 10.5458/jag.52.261] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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Kimura I, Oshima H, Sasahara H, Kimura Y, Tajima S. Cloning, Sequencing and Expression Analysis of an Endo-1,4-.BETA.-D-Xylanase Gene from Aspergillus sojae. J Appl Glycosci (1999) 2004. [DOI: 10.5458/jag.51.237] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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de Vries RP, Visser J. Aspergillus enzymes involved in degradation of plant cell wall polysaccharides. Microbiol Mol Biol Rev 2001; 65:497-522, table of contents. [PMID: 11729262 PMCID: PMC99039 DOI: 10.1128/mmbr.65.4.497-522.2001] [Citation(s) in RCA: 542] [Impact Index Per Article: 23.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Degradation of plant cell wall polysaccharides is of major importance in the food and feed, beverage, textile, and paper and pulp industries, as well as in several other industrial production processes. Enzymatic degradation of these polymers has received attention for many years and is becoming a more and more attractive alternative to chemical and mechanical processes. Over the past 15 years, much progress has been made in elucidating the structural characteristics of these polysaccharides and in characterizing the enzymes involved in their degradation and the genes of biotechnologically relevant microorganisms encoding these enzymes. The members of the fungal genus Aspergillus are commonly used for the production of polysaccharide-degrading enzymes. This genus produces a wide spectrum of cell wall-degrading enzymes, allowing not only complete degradation of the polysaccharides but also tailored modifications by using specific enzymes purified from these fungi. This review summarizes our current knowledge of the cell wall polysaccharide-degrading enzymes from aspergilli and the genes by which they are encoded.
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Affiliation(s)
- R P de Vries
- Molecular Genetics of Industrial Microorganisms, Wageningen University, 6703 HA Wageningen, The Netherlands.
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Shofiqur Rahman AK, Kawamura S, Hatsu M, Hoq MM, Takamizawa K. Physicochemical properties of a novel alpha-L-arabinofuranosidase from Rhizomucor pusillus HHT-1. Can J Microbiol 2001; 47:767-72. [PMID: 11575504 DOI: 10.1139/w01-064] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The zygomycete fungus Rhizomucor pusillus HHT-1, cultured on L(+)arabinose as a sole carbon source, produced extracellular alpha-L-arabinofuranosidase. The enzyme was purified by (NH4)2SO4 fractionation, gel filtration, and ion exchange chromatography. The molecular mass of this monomeric enzyme was 88 kDa. The native enzyme had a pI of 4.2 and displayed a pH optimum and stability of 4.0 and 7.0-10.0, respectively. The temperature optimum was 65 degrees C, and it was stable up to 70 degrees C. The Km and Vmax for p-nitrophenyl alpha-L-arabinofuranoside were 0.59 mM and 387 micromol x min(-1) x mg(-1) protein, respectively. Activity was not stimulated by metal cofactors. The N-terminal amino acid sequence did not show any similarity to other arabinofuranosidases. Higher hydrolytic activity was recorded with pnitrophenyl alpha-L-arabinofuranoside, arabinotriose, and sugar beet arabinan; lower hydrolytic activity was recorded with oat-spelt xylan and arabinogalactan, indicating specificity for the low molecular mass L(+)-arabinose containing oligosaccharides with furanoside configuration.
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Affiliation(s)
- A K Shofiqur Rahman
- Department of Bioprocessing, Faculty of Agriculture, Gifu University, Yanagido, Japan
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