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Chen Z, Chen J, Ni D, Xu W, Zhang W, Mu W. Microbial dextran-hydrolyzing enzyme: Properties, structural features, and versatile applications. Food Chem 2024; 437:137951. [PMID: 37951078 DOI: 10.1016/j.foodchem.2023.137951] [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: 06/09/2023] [Revised: 10/28/2023] [Accepted: 11/06/2023] [Indexed: 11/13/2023]
Abstract
Dextran, an α-glucan mainly composed of (α1 → 6) linkages, has been widely applied in the food, cosmetic, and medicine industries. Dextranase can hydrolyze dextran to synthesize oligodextrans, which show prominent properties and promising applications in the food industry. Dextranases are widely distributed in bacteria, yeasts, and fungus, and classified into glycoside hydrolase (GH) 13, 15, 31, 49, and 66 families according to their sequence similarity, structural features, and reaction types. Dextranase, as a dextran-hydrolyzing enzyme, displays great application potential in the sugar-making, oral health care, medicine, and biotechnology industries. Here we mainly focused on presenting the enzymatic properties, structural features, and versatile (potential) applications of dextranase. To date, seven crystal structures of dextranases from GH 13, 15, 31, 49, and 66 families have been successfully solved. However, their molecular mechanisms for hydrolyzing dextran, especially on the size determinants of the hydrolysates, remain largely unknown. Additionally, the classification, microbial distribution, and immobilization technology of dextranase were also discussed in detail. This review discussed dextranase from different aspects with the ambition to present how they constitute the groundwork for promising future developments.
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Affiliation(s)
- Ziwei Chen
- School of Food and Biological Engineering, Jiangsu University, 301 Xuefu Road, Zhenjiang 212013, Jiangsu, China
| | - Jiajun Chen
- State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Dawei Ni
- State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Wei Xu
- State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi, Jiangsu 214122, China
| | - Wenli Zhang
- State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi, Jiangsu 214122, China.
| | - Wanmeng Mu
- State Key Laboratory of Food Science and Resources, Jiangnan University, Wuxi, Jiangsu 214122, China; International Joint Laboratory on Food Safety, Jiangnan University, Wuxi, Jiangsu 214122, China
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2
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Hu X, Xia B, Ru W, Zhang Y, Yang J, Zhang H. Research progress on structure and catalytic mechanism of dextranase. EFOOD 2023. [DOI: 10.1002/efd2.60] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Affiliation(s)
- Xue‐Qin Hu
- School of Food and Biological Engineering Hefei University of Technology Hefei China
| | - Bing‐Bing Xia
- School of Food and Biological Engineering Hefei University of Technology Hefei China
| | - Wei‐Juan Ru
- School of Food and Biological Engineering Hefei University of Technology Hefei China
| | - Yu‐Xin Zhang
- School of Food and Biological Engineering Hefei University of Technology Hefei China
| | - Jing‐Wen Yang
- School of Food and Biological Engineering Hefei University of Technology Hefei China
| | - Hong‐Bin Zhang
- School of Food and Biological Engineering Hefei University of Technology Hefei China
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Liu H, Ren W, Ly M, Li H, Wang S. Characterization of an Alkaline GH49 Dextranase from Marine Bacterium Arthrobacter oxydans KQ11 and Its Application in the Preparation of Isomalto-Oligosaccharide. Mar Drugs 2019; 17:md17080479. [PMID: 31430863 PMCID: PMC6723167 DOI: 10.3390/md17080479] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Revised: 08/06/2019] [Accepted: 08/09/2019] [Indexed: 11/16/2022] Open
Abstract
A GH49 dextranase gene DexKQ was cloned from marine bacteria Arthrobacter oxydans KQ11. It was recombinantly expressed using an Escherichia coli system. Recombinant DexKQ dextranase of 66 kDa exhibited the highest catalytic activity at pH 9.0 and 55 °C. kcat/Km of recombinant DexKQ at the optimum condition reached 3.03 s−1 μM−1, which was six times that of commercial dextranase (0.5 s−1 μM−1). DexKQ possessed a Km value of 67.99 µM against dextran T70 substrate with 70 kDa molecular weight. Thin-layer chromatography (TLC) analysis showed that main hydrolysis end products were isomalto-oligosaccharide (IMO) including isomaltotetraose, isomaltopantose, and isomaltohexaose. When compared with glucose, IMO could significantly improve growth of Bifidobacterium longum and Lactobacillus rhamnosus and inhibit growth of Escherichia coli and Staphylococcus aureus. This is the first report of dextranase from marine bacteria concerning recombinant expression and application in isomalto-oligosaccharide preparation.
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Affiliation(s)
- Hongfei Liu
- Jiangsu Key Laboratory of Marine Bioresources and Environment/Jiangsu Key Laboratory of Marine Biotechnology, Jiangsu Ocean University, Lianyungang 222005, China
| | - Wei Ren
- Jiangsu Key Laboratory of Marine Bioresources and Environment/Jiangsu Key Laboratory of Marine Biotechnology, Jiangsu Ocean University, Lianyungang 222005, China
- Collaborative Innovation Center of Modern Bio-Manufacture, Anhui University, Hefei 230039, China
| | - Mingsheng Ly
- Jiangsu Key Laboratory of Marine Bioresources and Environment/Jiangsu Key Laboratory of Marine Biotechnology, Jiangsu Ocean University, Lianyungang 222005, China
- Co-Innovation Center of Jiangsu Marine Bio-Industry Technology, Jiangsu Ocean University, Lianyungang 222005, China
| | - Haifeng Li
- Medical College, Hangzhou Normal University, Hangzhou 311121, China.
| | - Shujun Wang
- Jiangsu Key Laboratory of Marine Bioresources and Environment/Jiangsu Key Laboratory of Marine Biotechnology, Jiangsu Ocean University, Lianyungang 222005, China.
- Co-Innovation Center of Jiangsu Marine Bio-Industry Technology, Jiangsu Ocean University, Lianyungang 222005, China.
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Simón M, Montiel R, Smerling A, Solórzano E, Díaz N, Álvarez-Sandoval BA, Jiménez-Marín AR, Malgosa A. Molecular analysis of ancient caries. Proc Biol Sci 2015; 281:rspb.2014.0586. [PMID: 25056622 DOI: 10.1098/rspb.2014.0586] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
An 84 base pair sequence of the Streptococcus mutans virulence factor, known as dextranase, has been obtained from 10 individuals from the Bronze Age to the Modern Era in Europe and from before and after the colonization in America. Modern samples show four polymorphic sites that have not been found in the ancient samples studied so far. The nucleotide and haplotype diversity of this region have increased over time, which could be reflecting the footprint of a population expansion. While this segment has apparently evolved according to neutral evolution, we have been able to detect one site that is under positive selection pressure both in present and past populations. This study is a first step to study the evolution of this microorganism, analysed using direct evidence obtained from ancient remains.
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Affiliation(s)
- Marc Simón
- Unitat d'Antropologia Biològica, Department of Biologia Animal, Biologia Vegetal i Ecologia, Universitat Autònoma de Barcelona, Spain
| | - Rafael Montiel
- Laboratorio Nacional de Genómica para la Biodiversidad, Unidad de Genómica Avanzada, CINVESTAV-IPN. Km. 9.6 Libramiento Norte Carretera Irapuato - León, Irapuato, Guanajuato, Mexico
| | - Andrea Smerling
- Unitat d'Antropologia Biològica, Department of Biologia Animal, Biologia Vegetal i Ecologia, Universitat Autònoma de Barcelona, Spain
| | - Eduvigis Solórzano
- Unitat d'Antropologia Biològica, Department of Biologia Animal, Biologia Vegetal i Ecologia, Universitat Autònoma de Barcelona, Spain
| | - Nancy Díaz
- Unitat d'Antropologia Biològica, Department of Biologia Animal, Biologia Vegetal i Ecologia, Universitat Autònoma de Barcelona, Spain
| | - Brenda A Álvarez-Sandoval
- Laboratorio Nacional de Genómica para la Biodiversidad, Unidad de Genómica Avanzada, CINVESTAV-IPN. Km. 9.6 Libramiento Norte Carretera Irapuato - León, Irapuato, Guanajuato, Mexico
| | - Andrea R Jiménez-Marín
- Laboratorio Nacional de Genómica para la Biodiversidad, Unidad de Genómica Avanzada, CINVESTAV-IPN. Km. 9.6 Libramiento Norte Carretera Irapuato - León, Irapuato, Guanajuato, Mexico
| | - Assumpció Malgosa
- Unitat d'Antropologia Biològica, Department of Biologia Animal, Biologia Vegetal i Ecologia, Universitat Autònoma de Barcelona, Spain
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Abstract
The complete nucleotide sequence of the dextranase gene of Streptococcus rattus ATCC19645 was determined. An open reading frame of the dextranase gene was 2,760 bp long and encoded a dextranase protein consisting of 920 amino acids with a molecular weight of 100,163 Da and an isoelectric point of 4.67. The S. rattus dextranase purified from recombinant Escherichia coli cells showed dextran-hydrolyzing activity with optimal pH (5.0) and temperature (40 C) similar to those of dextranases from Streptococcus mutans and Streptococcus sobrinus. The deduced amino acid sequence of the S. rattus dextranase revealed that the dextranase molecule consists of two variable regions and a conserved region. The variable regions contained an N-terminal signal peptide and a C-terminal cell wall sorting signal; the conserved region contained two functional domains, catalytic and dextran-binding sites. This structural feature of the S. rattus dextranase is quite similar to that of other cariogenic species such as S. mutans, S. sobrinus, and Streptococcus downei.
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Affiliation(s)
- Takeshi Igarashi
- Department of Oral Microbiology, Showa University School of Dentistry, Tokyo, Japan.
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Suzuki N, Kim YM, Fujimoto Z, Momma M, Okuyama M, Mori H, Funane K, Kimura A. Structural elucidation of dextran degradation mechanism by streptococcus mutans dextranase belonging to glycoside hydrolase family 66. J Biol Chem 2012; 287:19916-26. [PMID: 22337884 DOI: 10.1074/jbc.m112.342444] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Dextranase is an enzyme that hydrolyzes dextran α-1,6 linkages. Streptococcus mutans dextranase belongs to glycoside hydrolase family 66, producing isomaltooligosaccharides of various sizes and consisting of at least five amino acid sequence regions. The crystal structure of the conserved fragment from Gln(100) to Ile(732) of S. mutans dextranase, devoid of its N- and C-terminal variable regions, was determined at 1.6 Å resolution and found to contain three structural domains. Domain N possessed an immunoglobulin-like β-sandwich fold; domain A contained the enzyme's catalytic module, comprising a (β/α)(8)-barrel; and domain C formed a β-sandwich structure containing two Greek key motifs. Two ligand complex structures were also determined, and, in the enzyme-isomaltotriose complex structure, the bound isomaltooligosaccharide with four glucose moieties was observed in the catalytic glycone cleft and considered to be the transglycosylation product of the enzyme, indicating the presence of four subsites, -4 to -1, in the catalytic cleft. The complexed structure with 4',5'-epoxypentyl-α-d-glucopyranoside, a suicide substrate of the enzyme, revealed that the epoxide ring reacted to form a covalent bond with the Asp(385) side chain. These structures collectively indicated that Asp(385) was the catalytic nucleophile and that Glu(453) was the acid/base of the double displacement mechanism, in which the enzyme showed a retaining catalytic character. This is the first structural report for the enzyme belonging to glycoside hydrolase family 66, elucidating the enzyme's catalytic machinery.
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Affiliation(s)
- Nobuhiro Suzuki
- Biomolecular Research Unit, National Institute of Agrobiological Sciences, 2-1-2 Kannondai, Tsukuba 305-8602, Japan
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Suzuki N, Kim YM, Fujimoto Z, Momma M, Kang HK, Funane K, Okuyama M, Mori H, Kimura A. Crystallization and preliminary crystallographic analysis of dextranase from Streptococcus mutans. Acta Crystallogr Sect F Struct Biol Cryst Commun 2011; 67:1542-4. [PMID: 22139161 PMCID: PMC3232134 DOI: 10.1107/s1744309111038425] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2011] [Accepted: 09/19/2011] [Indexed: 11/10/2022]
Abstract
Streptococcus mutans dextranase hydrolyzes the internal α-1,6-linkages of dextran and belongs to glycoside hydrolase family 66. An N- and C-terminal deletion mutant of S. mutans dextranase was crystallized by the sitting-drop vapour-diffusion method. The crystals diffracted to a resolution of 1.6 Å and belonged to space group P2(1), with unit-cell parameters a = 53.2, b = 89.7, c = 63.3 Å, β = 102.3°. Assuming that the asymmetric unit of the crystal contained one molecule, the Matthews coefficient was calculated to be 4.07 Å(3) Da(-1); assuming the presence of two molecules in the asymmetric unit it was calculated to be 2.03 Å(3) Da(-1).
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Affiliation(s)
- Nobuhiro Suzuki
- Biomolecular Research Unit, National Institute of Agrobiological Sciences, 2-1-2 Kannondai, Tsukuba, Ibaraki 305-8602, Japan
| | - Young-Min Kim
- Biomolecular Research Unit, National Institute of Agrobiological Sciences, 2-1-2 Kannondai, Tsukuba, Ibaraki 305-8602, Japan
- Research Faculty of Agriculture, Hokkaido University, Kita-9 Nishi-9, Kita-ku, Sapporo 060-8589, Japan
| | - Zui Fujimoto
- Biomolecular Research Unit, National Institute of Agrobiological Sciences, 2-1-2 Kannondai, Tsukuba, Ibaraki 305-8602, Japan
| | - Mitsuru Momma
- Biomolecular Research Unit, National Institute of Agrobiological Sciences, 2-1-2 Kannondai, Tsukuba, Ibaraki 305-8602, Japan
| | - Hee-Kwon Kang
- Research Faculty of Agriculture, Hokkaido University, Kita-9 Nishi-9, Kita-ku, Sapporo 060-8589, Japan
| | - Kazumi Funane
- Applied Microbiology Division, National Food Research Institute, 2-1-12 Kannondai, Tsukuba 305-8642, Japan
| | - Masayuki Okuyama
- Research Faculty of Agriculture, Hokkaido University, Kita-9 Nishi-9, Kita-ku, Sapporo 060-8589, Japan
| | - Haruhide Mori
- Research Faculty of Agriculture, Hokkaido University, Kita-9 Nishi-9, Kita-ku, Sapporo 060-8589, Japan
| | - Atsuo Kimura
- Research Faculty of Agriculture, Hokkaido University, Kita-9 Nishi-9, Kita-ku, Sapporo 060-8589, Japan
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Truncation of N- and C-terminal regions of Streptococcus mutans dextranase enhances catalytic activity. Appl Microbiol Biotechnol 2011; 91:329-39. [DOI: 10.1007/s00253-011-3201-y] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2010] [Revised: 02/16/2011] [Accepted: 02/18/2011] [Indexed: 10/18/2022]
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Tamura H, Yamada A, Kato H. Identification and characterization of a dextranase gene of Streptococcus criceti. Microbiol Immunol 2008; 51:721-32. [PMID: 17704634 DOI: 10.1111/j.1348-0421.2007.tb03961.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The dextranase gene, dex, was identified in Streptococcus criceti strain E49 by degenerate PCR and sequenced completely by the gene-walking method. A sequence of 3,960 nucleotides was determined. The dex gene encodes a 1,200-amino acid protein, which has a calculated molecular mass of 128,129.91 and pI of 4.15 and is predicted to be a cell-surface protein. The deduced amino acid sequence of dex showed homology to S. downei dextranase (63.9% identity). Phylogenetic analysis revealed the similarity of the deduced amino acid sequence of dextranases in S. criceti, S. sobrinus, and S. downei. A recombinant form of the protein with six histidine residues tagged in the C-terminus was partially purified and showed dextranase activity on blue-dextran sodium dodecyl sulfate-polyacrylamide gel electrophoresis (BD-SDSPAGE) followed by renaturation. We also detected dextranase activity in S. criceti cell extracts and culture supernatant by renatured BD-SDS-PAGE, whereas no dextranase activity of the cells was observed on blue-dextran brain heart infusion (BD-BHI) agar plates. Furthermore, PCR-based mutations of dextranase indicated that a deletion mutant of the C-terminal region could hydrolyze blue dextrans and that the D453E mutation, W793L mutation, and double mutations (W793L and deletion of the C-terminal region) resulted in a loss of dextranase activity. These findings suggest that Asp-453 and Trp-793 residues of S. criceti dextranase are critical to the enzyme's activity.
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Affiliation(s)
- Haruki Tamura
- Department of Dental Pharmacology, School of Dentistry, Iwate Medical University, Morioka, Iwate 020-8505, Japan.
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Hild E, Brumbley SM, O'Shea MG, Nevalainen H, Bergquist PL. A Paenibacillus sp. dextranase mutant pool with improved thermostability and activity. Appl Microbiol Biotechnol 2007; 75:1071-8. [PMID: 17426967 DOI: 10.1007/s00253-007-0936-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2007] [Revised: 03/06/2007] [Accepted: 03/07/2007] [Indexed: 10/23/2022]
Abstract
Random mutagenesis was used to create a library of chimeric dextranase (dex1) genes. A plate-screening protocol was developed with improved thermostability as a selection criterion. The mutant library was screened for active dextranase variants by observing clearing zones on dextran-blue agar plates at 50 degrees C after exposure to 68 degrees C for 2 h, a temperature regime at which wild-type activity was abolished. A number of potentially improved variants were identified by this strategy, five of which were further characterised. DNA sequencing revealed ten nucleotide substitutions, ranging from one to four per variant. Thermal inactivation studies showed reduced (2.9-fold) thermostability for one variant and similar thermostability for a second variant, but confirmed improved thermostability for three mutants with 2.3- (28.9 min) to 6.9-fold (86.6 min) increases in half-lives at 62 degrees C compared to that of the wild-type enzyme (12.6 min). Using a 10-min assay, apparent temperature optima of the variants were similar to that of the wild type (T (opt) 60 degrees C). However, one of these variants had increased enzyme activity. Therefore, the first-generation dextranase mutant pool obtained in this study has sufficient molecular diversity for further improvements in both thermostability and activity through recombination (gene shuffling).
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Affiliation(s)
- Erika Hild
- Department of Chemistry & Biomolecular Sciences, Macquarie University, Sydney, New South Wales, 2109, Australia
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Khalikova E, Susi P, Korpela T. Microbial dextran-hydrolyzing enzymes: fundamentals and applications. Microbiol Mol Biol Rev 2005; 69:306-25. [PMID: 15944458 PMCID: PMC1197420 DOI: 10.1128/mmbr.69.2.306-325.2005] [Citation(s) in RCA: 149] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Dextran is a chemically and physically complex polymer, breakdown of which is carried out by a variety of endo- and exodextranases. Enzymes in many groups can be classified as dextranases according to function: such enzymes include dextranhydrolases, glucodextranases, exoisomaltohydrolases, exoisomaltotriohydrases, and branched-dextran exo-1,2-alpha-glucosidases. Cycloisomalto-oligosaccharide glucanotransferase does not formally belong to the dextranases even though its side reaction produces hydrolyzed dextrans. A new classification system for glycosylhydrolases and glycosyltransferases, which is based on amino acid sequence similarities, divides the dextranases into five families. However, this classification is still incomplete since sequence information is missing for many of the enzymes that have been biochemically characterized as dextranases. Dextran-degrading enzymes have been isolated from a wide range of microorganisms. The major characteristics of these enzymes, the methods for analyzing their activities and biological roles, analysis of primary sequence data, and three-dimensional structures of dextranases have been dealt with in this review. Dextranases are promising for future use in various scientific and biotechnological applications.
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Affiliation(s)
- Elvira Khalikova
- Joint Biotechnology Laboratory, Department of Chemistry, University of Turku, Finland
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Finnegan PM, Brumbley SM, O'Shea MG, Nevalainen H, Bergquist PL. Diverse dextranase genes from Paenibacillus species. Arch Microbiol 2005; 183:140-7. [PMID: 15645216 DOI: 10.1007/s00203-004-0756-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2004] [Revised: 12/02/2004] [Accepted: 12/14/2004] [Indexed: 10/25/2022]
Abstract
Genes encoding dextranolytic enzymes were isolated from Paenibacillus strains Dex40-8 and Dex50-2. Single, similar but non-identical dex1 genes were isolated from each strain, and a more divergent dex2 gene was isolated from strain Dex50-2. The protein deduced from the Dex40-8 dex1 gene sequence had 716 amino acids, with a predicted M(r) of 80.8 kDa. The proteins deduced from the Dex50-2 dex1 and dex2 gene sequences had 905 and 596 amino acids, with predicted M(r) of 100.1 kDa and 68.3 kDa, respectively. The deduced amino acid sequences of all three dextranolytic proteins had similarity to family 66 glycosyl hydrolases and were predicted to possess cleavable N-terminal signal peptides. Homology searches suggest that the Dex40-8 and Dex50-2 Dex1 proteins have one and two copies, respectively, of a carbohydrate-binding module similar to CBM_4_9 (pfam02018.11). The Dex50-2 Dex2 deduced amino acid sequence had highest sequence similarity to thermotolerant dextranases from thermophilic Paenibacillus strains, while the Dex40-8 and Dex50-2 Dex1 deduced protein sequences formed a distinct sequence clade among the family 66 proteins. Examination of seven Paenibacillus strains, using a polymerase chain reaction-based assay, indicated that multiple family 66 genes are common within this genus. The three recombinant proteins expressed in Escherichia coli possessed dextranolytic activity and were able to convert ethanol-insoluble blue dextran into an ethanol-soluble product, indicating they are endodextranases (EC 3.2.1.11). The reaction catalysed by each enzyme had a distinct temperature and pH dependence.
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Affiliation(s)
- Patrick M Finnegan
- School of Plant Biology, University of Western Australia, Crawley, WA, 6009, Australia
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