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Hovorková M, Kulik N, Konvalinková D, Petrásková L, Křen V, Bojarová P. Mutagenesis of Catalytic Nucleophile of β‐Galactosidase Retains Residual Hydrolytic Activity and Affords a Transgalactosidase. ChemCatChem 2021. [DOI: 10.1002/cctc.202101107] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Affiliation(s)
- Michaela Hovorková
- Laboratory of Biotransformation Institute of Microbiology Czech Academy of Sciences Vídeňská 1083 CZ-14220 Prague 4 Czech Republic
- Department of Genetics and Microbiology Faculty of Science Charles University Viničná 5 CZ-12843 Prague 2 Czech Republic
| | - Natalia Kulik
- Center for Nanobiology and Structural Biology Institute of Microbiology Czech Academy of Sciences Zámek 136 CZ-37333 Nové Hrady Czech Republic
| | - Dorota Konvalinková
- Laboratory of Biotransformation Institute of Microbiology Czech Academy of Sciences Vídeňská 1083 CZ-14220 Prague 4 Czech Republic
| | - Lucie Petrásková
- Laboratory of Biotransformation Institute of Microbiology Czech Academy of Sciences Vídeňská 1083 CZ-14220 Prague 4 Czech Republic
| | - Vladimír Křen
- Laboratory of Biotransformation Institute of Microbiology Czech Academy of Sciences Vídeňská 1083 CZ-14220 Prague 4 Czech Republic
| | - Pavla Bojarová
- Laboratory of Biotransformation Institute of Microbiology Czech Academy of Sciences Vídeňská 1083 CZ-14220 Prague 4 Czech Republic
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Hoffmann M, Hayes MR, Pietruszka J, Elling L. Synthesis of the Thomsen-Friedenreich-antigen (TF-antigen) and binding of Galectin-3 to TF-antigen presenting neo-glycoproteins. Glycoconj J 2020; 37:457-470. [PMID: 32367478 PMCID: PMC7329766 DOI: 10.1007/s10719-020-09926-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Accepted: 04/13/2020] [Indexed: 12/13/2022]
Abstract
The Thomsen-Friedenreich-antigen, Gal(β1-3)GalNAc(α1-O-Ser/Thr (TF-antigen), is presented on the surface of most human cancer cell types. Its interaction with galectin 1 and galectin 3 leads to tumor cell aggregation and promotes cancer metastasis and T-cell apoptosis in epithelial tissue. To further explore multivalent binding between the TF-antigen and galectin-3, the TF-antigen was enzymatically synthesized in high yields with GalNAc(α1-EG3-azide as the acceptor substrate by use of the glycosynthase BgaC/Glu233Gly. Subsequently, it was coupled to alkynyl-functionalized bovine serum albumin via a copper(I)-catalyzed alkyne-azide cycloaddition. This procedure yielded neo-glycoproteins with tunable glycan multivalency for binding studies. Glycan densities between 2 and 53 glycan residues per protein molecule were obtained by regulated alkynyl-modification of the lysine residues of BSA. The number of coupled glycans was quantified by sodium dodecyl sulfate polyacrylamide gel electrophoresis and a trinitrobenzene sulfonic acid assay. The binding efficiency of the neo-glycoproteins with human galectin-3 and the effect of multivalency was investigated and assessed using an enzyme-linked lectin assay. Immobilized neo-glycoproteins of all modification densities showed binding of Gal-3 with increasing glycan density. However, multivalent glycan presentation did not result in a higher binding affinity. In contrast, inhibition of Gal-3 binding to asialofetuin was effective. The relative inhibitory potency was increased by a factor of 142 for neo-glycoproteins displaying 10 glycans/protein in contrast to highly decorated inhibitors with only 2-fold increase. In summary, the functionality of BSA-based neo-glycoproteins presenting the TF-antigen as multivalent inhibitors for Gal-3 was demonstrated.
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Affiliation(s)
- Marius Hoffmann
- Laboratory for Biomaterials, Institute for Biotechnology and Helmholtz-Institute for Biomedical Engineering, RWTH Aachen University, Pauwelsstraße. 20, 52074 Aachen, Germany
| | - Marc R. Hayes
- Institute for Bioorganic Chemistry, Heinrich Heine University Düsseldorf at Forschungszentrum Jülich, 52426 Jülich, Germany
| | - Jörg Pietruszka
- Institute for Bioorganic Chemistry, Heinrich Heine University Düsseldorf at Forschungszentrum Jülich, 52426 Jülich, Germany
- Forschungszentrum Jülich, IBG-1: Biotechnology, 52426 Jülich, Germany
| | - Lothar Elling
- Laboratory for Biomaterials, Institute for Biotechnology and Helmholtz-Institute for Biomedical Engineering, RWTH Aachen University, Pauwelsstraße. 20, 52074 Aachen, Germany
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Yang X, Liu Z, Jiang C, Sun J, Xue C, Mao X. A novel agaro-oligosaccharide-lytic β-galactosidase from Agarivorans gilvus WH0801. Appl Microbiol Biotechnol 2018; 102:5165-5172. [PMID: 29682702 DOI: 10.1007/s00253-018-8999-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2018] [Revised: 04/03/2018] [Accepted: 04/07/2018] [Indexed: 11/30/2022]
Abstract
β-Galactosidases have a wide application in the food and pharmaceutical industries. Recently, β-galactosidase was also found to participate in agar degradation. In this study, the second reported agarolytic β-galactosidase was found in the marine bacterium Agarivorans gilvus WH0801 and characterized. The β-galactosidase named AgWH2A (83 kDa) exhibited good activities under optimal hydrolysis conditions of pH 8.0 and 40 °C. AgWH2A could cleave the first D-galactose of agarooligosaccharides from its nonreducing end to produce neoagarooligosaccharides, but could not act on the neoagarooligosaccharides. AgWH2A has great potential in the comprehensive utilization of marine red algae.
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Affiliation(s)
- Xiaoqing Yang
- College of Food Science and Engineering, Ocean University of China, Qingdao, 266003, China
| | - Zhen Liu
- College of Food Science and Engineering, Ocean University of China, Qingdao, 266003, China
| | - Chengcheng Jiang
- College of Food Science and Engineering, Ocean University of China, Qingdao, 266003, China
| | - Jianan Sun
- College of Food Science and Engineering, Ocean University of China, Qingdao, 266003, China
| | - Changhu Xue
- College of Food Science and Engineering, Ocean University of China, Qingdao, 266003, China.,Laboratory for Marine Drugs and Bioproducts, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237, China
| | - Xiangzhao Mao
- College of Food Science and Engineering, Ocean University of China, Qingdao, 266003, China. .,Laboratory for Marine Drugs and Bioproducts, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237, China.
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Active site titration of immobilized beta-galactosidase for the determination of active enzymes. Biochem Eng J 2015. [DOI: 10.1016/j.bej.2014.10.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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5
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Rational design of a glycosynthase by the crystal structure of β-galactosidase from Bacillus circulans (BgaC) and its use for the synthesis of N-acetyllactosamine type 1 glycan structures. J Biotechnol 2014; 191:78-85. [PMID: 25034434 DOI: 10.1016/j.jbiotec.2014.07.003] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2014] [Revised: 07/01/2014] [Accepted: 07/04/2014] [Indexed: 11/20/2022]
Abstract
The crystal structure of β-galactosidase from Bacillus circulans (BgaC) was determined at 1.8Å resolution. The overall structure of BgaC consists of three distinct domains, which are the catalytic domain with a TIM-barrel structure and two all-β domains (ABDs). The main-chain fold and steric configurations of the acidic and aromatic residues at the active site were very similar to those of Streptococcus pneumoniae β(1,3)-galactosidase BgaC in complex with galactose. The structure of BgaC was used for the rational design of a glycosynthase. BgaC belongs to the glycoside hydrolase family 35. The essential nucleophilic amino acid residue has been identified as glutamic acid at position 233 by site-directed mutagenesis. Construction of the active site mutant BgaC-Glu233Gly gave rise to a galactosynthase transferring the sugar moiety from α-d-galactopyranosyl fluoride (αGalF) to different β-linked N-acetylglucosamine acceptor substrates in good yield (40-90%) with a remarkably stable product formation. Enzymatic syntheses with BgaC-Glu233Gly afforded the stereo- and regioselective synthesis of β1-3-linked key galactosides like galacto-N-biose or lacto-N-biose.
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Li C, Kim YW. Characterization of a Galactosynthase Derived fromBacillus circulansβ-Galactosidase: Facile Synthesis ofD-Lacto- andD-Galacto-N-bioside. Chembiochem 2014; 15:522-6. [DOI: 10.1002/cbic.201300699] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2013] [Indexed: 11/10/2022]
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Durantie E, Bucher C, Gilmour R. Fluorine-directed β-galactosylation: chemical glycosylation development by molecular editing. Chemistry 2012; 18:8208-15. [PMID: 22592962 DOI: 10.1002/chem.201200468] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2012] [Indexed: 11/10/2022]
Abstract
Validation of the 2-fluoro substituent as an inert steering group to control chemical glycosylation is presented. A molecular editing study has revealed that the exceptional levels of diastereocontrol in glycosylation processes by using 2-fluoro-3,4,6-tri-O-benzyl glucopyranosyl trichloroacetimidate (TCA) scaffolds are a consequence of the 2R,3S,4S stereotriad. This study has also revealed that epimerization at C4, results in a substantial enhancement in β-selectivity (up to β/α 300:1).
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Affiliation(s)
- Estelle Durantie
- Laboratory for Organic Chemistry, Swiss Federal Institute of Technology (ETH) Zürich, 8093 Zürich, Switzerland
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O'Donoghue EM, Somerfield SD, Watson LM, Brummell DA, Hunter DA. Galactose metabolism in cell walls of opening and senescing petunia petals. PLANTA 2009; 229:709-721. [PMID: 19082620 DOI: 10.1007/s00425-008-0862-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2008] [Accepted: 11/13/2008] [Indexed: 05/27/2023]
Abstract
Galactose was the major non-cellulosic neutral sugar present in the cell walls of 'Mitchell' petunia (Petunia axillaris x P. axillaris x P. hybrida) flower petals. Over the 24 h period associated with flower opening, there was a doubling of the galactose content of polymers strongly associated with cellulose and insoluble in strong alkali ('residual' fraction). By two days after flower opening, the galactose content of both the residual fraction and a Na(2)CO(3)-soluble pectin-rich cell wall fraction had sharply decreased, and continued to decline as flowers began to wilt. In contrast, amounts of other neutral sugars showed little change over this time, and depolymerisation of pectins and hemicelluloses was barely detectable throughout petal development. Size exclusion chromatography of Na(2)CO(3)-soluble pectins showed that there was a loss of neutral sugar relative to uronic acid content, consistent with a substantial loss of galactose from rhamnogalacturonan-I-type pectin. beta-Galactosidase activity (EC 3.2.1.23) increased at bud opening, and remained high through to petal senescence. Two cDNAs encoding beta-galactosidase were isolated from a mixed stage petal library. Both deduced proteins are beta-galactosidases of Glycosyl Hydrolase Family 35, possessing lectin-like sugar-binding domains at their carboxyl terminus. PhBGAL1 was expressed at relatively high levels only during flower opening, while PhBGAL2 mRNA accumulation occurred at lower levels in mature and senescent petals. The data suggest that metabolism of cell wall-associated polymeric galactose is the major feature of both the opening and senescence of 'Mitchell' petunia flower petals.
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Affiliation(s)
- Erin M O'Donoghue
- New Zealand Institute for Plant and Food Research Limited, New Zealand.
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Dean GH, Zheng H, Tewari J, Huang J, Young DS, Hwang YT, Western TL, Carpita NC, McCann MC, Mansfield SD, Haughn GW. The Arabidopsis MUM2 gene encodes a beta-galactosidase required for the production of seed coat mucilage with correct hydration properties. THE PLANT CELL 2007; 19:4007-21. [PMID: 18165329 PMCID: PMC2217648 DOI: 10.1105/tpc.107.050609] [Citation(s) in RCA: 121] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2007] [Revised: 12/10/2007] [Accepted: 12/12/2007] [Indexed: 05/17/2023]
Abstract
Seed coat development in Arabidopsis thaliana involves a complex pathway where cells of the outer integument differentiate into a highly specialized cell type after fertilization. One aspect of this developmental process involves the secretion of a large amount of pectinaceous mucilage into the apoplast. When the mature seed coat is exposed to water, this mucilage expands to break the primary cell wall and encapsulate the seed. The mucilage-modified2 (mum2) mutant is characterized by a failure to extrude mucilage on hydration, although mucilage is produced as normal during development. The defect in mum2 appears to reside in the mucilage itself, as mucilage fails to expand even when the barrier of the primary cell wall is removed. We have cloned the MUM2 gene and expressed recombinant MUM2 protein, which has beta-galactosidase activity. Biochemical analysis of the mum2 mucilage reveals alterations in pectins that are consistent with a defect in beta-galactosidase activity, and we have demonstrated that MUM2 is localized to the cell wall. We propose that MUM2 is involved in modifying mucilage to allow it to expand upon hydration, establishing a link between the galactosyl side-chain structure of pectin and its physical properties.
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Affiliation(s)
- Gillian H Dean
- Department of Botany, University of British Columbia, Vancouver, Canada V6T 1Z4
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Yang TC, Hu RM, Weng SF, Tseng YH. Identification of a hypothetical protein of plant pathogenic Xanthomonas campestris as a novel beta-galactosidase. J Mol Microbiol Biotechnol 2007; 13:172-80. [PMID: 17693725 DOI: 10.1159/000103609] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Xc17L, a lactose-utilizing mutant of Xanthomonas campestris pv. campestris previously isolated by mutagenesis with nitrous acid, displays a level of beta-galactosidase 3.5-fold higher than that in the parental Xc17. In this study, the gene encoding the enzyme displaying a higher specific activity in Xc17L was inactivated by mini-Tn5 transposition. Sequencing revealed that the product (579 aa, 63.5 kDa) of this gene, designated galD, was previously annotated to encode a hypothetical protein on the genome. Mutation of the gene by marker exchange, complementation test and Western blot analysis together confirmed that galD is indeed the gene involved in beta-galactosidase elevation in Xc17L. With only the N-terminal region possessing similarity to the known beta-galactosidases and partially conserved consensus motif, GalD is recognized as a member of the glycosyl hydrolase family 35. Insertion with GmOmega, which causes polar effects, into the upstream genes followed by Western blotting showed that galD is cotranscribed with the upstream genes and expressed constitutively. Mutation in galD causes no significant changes including pathogenicity in the bacterium.
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Affiliation(s)
- Tsuey-Ching Yang
- Department of Medical Laboratory Science and Biotechnology, China Medical University, Taichung, Taiwan, ROC
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Kim YW, Chen HM, Kim JH, Müllegger J, Mahuran D, Withers SG. Thioglycoligase-based assembly of thiodisaccharides: screening as beta-galactosidase inhibitors. Chembiochem 2007; 8:1495-9. [PMID: 17661304 PMCID: PMC2910745 DOI: 10.1002/cbic.200700263] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Young-Wan Kim
- Department of Chemistry, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
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Shaikh FA, Müllegger J, He S, Withers SG. Identification of the catalytic nucleophile in Family 42 beta-galactosidases by intermediate trapping and peptide mapping: YesZ from Bacillus subtilis. FEBS Lett 2007; 581:2441-6. [PMID: 17485082 DOI: 10.1016/j.febslet.2007.04.053] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2007] [Revised: 04/18/2007] [Accepted: 04/21/2007] [Indexed: 11/26/2022]
Abstract
The mechanism-based inhibitor 2,4-dinitrophenyl 2-deoxy-2-fluoro-beta-d-galactopyranoside (DNP2FGal) was used to inactivate the Family 42 beta-galactosidase (YesZ) from Bacillus subtilis via the trapping of a glycosyl-enzyme intermediate, thereby tagging the catalytic nucleophile in the active site. Proteolytic digestion of the inactivated enzyme and of a control sample of unlabeled enzyme, followed by comparative high-performance liquid chromatography and mass spectrometric analysis identified a labelled peptide of the sequence ETSPSYAASL. These data, combined with sequence alignments of this region with representative members of Family 42, unequivocally identify the catalytic nucleophile in this enzyme as Glu-295, thereby providing the first direct experimental proof of the identity of this residue within Family 42.
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Affiliation(s)
- Fathima Aidha Shaikh
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, BC, Canada
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Kim YW, Chen H, Kim JH, Withers SG. Catalytic properties of a mutant β-galactosidase fromXanthomonas manihotisengineered to synthesize galactosyl-thio-β-1,3 and -β-1,4-glycosides. FEBS Lett 2006; 580:4377-81. [PMID: 16844121 DOI: 10.1016/j.febslet.2006.06.095] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2006] [Revised: 06/30/2006] [Accepted: 06/30/2006] [Indexed: 11/24/2022]
Abstract
The identity of the acid/base catalyst of the Family 35 beta-galactosidases from Xanthomonas manihotis (BgaX) has been confirmed as Glu184 by kinetic analysis of mutants modified at that position. The Glu184Ala mutant of BgaX is shown to function as an efficient thioglycoligase, which synthesises thiogalactosides with linkages to the 3 and 4 positions of glucosides and galactosides in high (>80%) yields. Kinetic analysis of the thioglycoligase reveals glycosyl donor K(m) values of 1.5-21 microM and glycosyl acceptor K(m) values from 180 to 500 microM. This mutant should be a valuable catalyst for the synthesis of metabolically stable analogues of this important glycosidic linkage.
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Affiliation(s)
- Young-Wan Kim
- Department of Chemistry, University of British Columbia, 2036 Main Mall, Vancouver, BC, Canada V6T 1Z1
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Ducros VMA, Tarling CA, Zechel DL, Brzozowski AM, Frandsen TP, von Ossowski I, Schülein M, Withers SG, Davies GJ. Anatomy of glycosynthesis: structure and kinetics of the Humicola insolens Cel7B E197A and E197S glycosynthase mutants. CHEMISTRY & BIOLOGY 2003; 10:619-28. [PMID: 12890535 DOI: 10.1016/s1074-5521(03)00143-1] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The formation of glycoconjugates and oligosaccharides remains one of the most challenging chemical syntheses. Chemo-enzymatic routes using retaining glycosidases have been successfully harnessed but require tight kinetic or thermodynamic control. "Glycosynthases," specifically engineered glycosidases that catalyze the formation of glycosidic bonds from glycosyl donor and acceptor alcohol, are an emerging range of synthetic tools in which catalytic nucleophile mutants are harnessed together with glycosyl fluoride donors to generate powerful and versatile catalysts. Here we present the structural and kinetic dissection of the Humicola insolens Cel7B glycosynthases in which the nucleophile of the wild-type enzyme is mutated to alanine and serine (E197A and E197S). 3-D structures reveal the acceptor and donor subsites and the basis for substrate inhibition. Kinetic analysis shows that the E197S mutant is considerably more active than the corresponding alanine mutant due to a 40-fold increase in k(cat).
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Affiliation(s)
- Valérie M-A Ducros
- Structural Biology Laboratory, Department of Chemistry, The University of York, Heslington, York YO10 5YW, United Kingdom
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Blanchard JE, Withers SG. Rapid screening of the aglycone specificity of glycosidases: applications to enzymatic synthesis of oligosaccharides. CHEMISTRY & BIOLOGY 2001; 8:627-33. [PMID: 11451664 DOI: 10.1016/s1074-5521(01)00038-2] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
BACKGROUND Retaining glycosidases can catalyse glycosidic bond formation through transglycosylation from a donor sugar to an acceptor bound in the aglycone site. The aglycone specificity of a glycosidase is not easily determined, thereby complicating the choice of the most appropriate glycosidase for use as a catalyst for transglycosylation. We have developed a strategy to rapidly screen the aglycone specificity of a glycosidase and thereby determine which enzymes are best suited to catalyse specific transglycosylation reactions. RESULTS The reactivation, or turnover, of a glycosidase trapped as a fluoroglycosyl-enzyme species is accelerated in the presence of a compound that productively binds to the aglycone site. This methodology was used to rapidly screen six glycosidases with 44 potential acceptor sugars. Validation of the screening strategy was demonstrated by the identification of products formed from a transglycosylation reaction with positively screened acceptors for four of the enzymes studied. CONCLUSIONS The aglycone specificity of a glycosidase can be rapidly evaluated and requires only an appropriate fluorosugar inactivator, a substrate for assay of activity and a library of compounds for screening.
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Affiliation(s)
- J E Blanchard
- Protein Engineering Network of Centres of Excellence of Canada and the Department of Chemistry, University of British Columbia, V6T 1Z1, Vancouver, BC, Canada
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