3482-57-3Relevant articles and documents
p-Aminophenyl β-cellobioside as an affinity ligand for exo-type cellulases
Sangseethong, Kunruedee,Penner, Michael H.
, p. 245 - 250 (1998)
p-Aminophenyl β-cellobioside (PAPC) is shown to be an effective affinity ligand for the chromatographic fractionation of cellobiohydrolases (CBHs). A crude cellulase preparation from the filamentous fungus Trichoderma reesei served as a representative sou
SYNTHETIC CATALYSTS FOR CARBOHYDRATE PROCESSING
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, (2022/01/24)
The disclosure relates to molecularly-imprinted cross-linked micelles that can selectively hydrolyze carbohydrates.
Acceptor-induced modification of regioselectivity in CGTase-catalyzed glycosylations of p-nitrophenyl-glucopyranosides
Strompen, Simon,Miranda-Molina, Alfonso,López-Munguía, Agustín,Castillo, Edmundo,Saab-Rincón, Gloria
, p. 46 - 54 (2015/03/05)
Cyclodextrin glycosyltransferases (CGTase) are reported to selectively catalyze α(1→4)-glycosyl transfer reactions besides showing low hydrolytic activity. Here, the effect of the anomeric configuration of the glycosyl acceptor on the regioselectivity of
Environmentally benign glycosylation of aryl pyranosides and aryl/alkyl furanosides demonstrating the versatility of thermostable CGTase from Thermoanaerobacterium sp.
Pennec, Alize,Legentil, Laurent,Herrera-Estrella, Luis,Ferrieres, Vincent,Chauvin, Anne-Laure,Nugier-Chauvin, Caroline
supporting information, p. 3803 - 3809 (2014/08/05)
An extensive study on the specificity of transglycosylation and disproportionation of Thermoanaerobacterium sp. cyclodextrin glucosyltransferases against aryl glucopyranosides or furanosides is reported. While a mixture of maltoside and isomaltoside was obtained respectively using p-nitrophenyl glucopyranoside as an acceptor, only one regioisomer, namely p-nitrophenyl α-d-Glcp-(1,3)-α-l-Araf, was isolated using p-nitrophenyl arabinofuranoside as an acceptor. Interestingly, similar outcomes were found when using p-nitrophenyl galactofuranoside. Furthermore, activation by microwave irradiation resulted in faster reaction times and higher yields and led to glucosidic oligosaccharides with up to 70% conversion. The influence of the anomeric and C-4 configurations of the glycosidic acceptors on the transglycosylation, previously stated for the CGTase family, was not observed and unconventional substrate specificity towards alkyl furanosides was highlighted. This journal is the Partner Organisations 2014.
Major change in regiospecificity for the exo-1,3-β-glucanase from Candida albicans following its conversion to a glycosynthase
Nakatani,Larsen,Cutfield,Cutfield
, p. 3318 - 3326 (2014/06/10)
The exo-1,3-β-glucanase (Exg) from Candida albicans is involved in cell wall β-d-glucan metabolism and morphogenesis through its hydrolase and transglycosidase activities. Previous work has shown that both these activities strongly favor β-1,3-linkages. The E292S Exg variant displayed modest glycosynthase activity using α-d-glucopyranosyl fluoride (α-GlcF) as the donor and pNP-β-d-glucopyranoside (pNPGlc) as the acceptor but surprisingly showed a marked preference for synthesizing β-1,6-linked over β-1,3- and β-1,4-linked disaccharide products. With pNPXyl as the acceptor, the preference became β-1,4 over β-1,3. The crystal structure of the glycosynthase bound to both of its substrates, α-GlcF and pNPGlc, is the first such ternary complex structure to be determined. The results revealed that the donor bound in the -1 subsite, as expected, while the acceptor was oriented in the +1 subsite to facilitate β-1,6-linkage, thereby supporting the results from solution studies. A second crystal structure containing the major product of glycosynthesis, pNP-gentiobiose, showed that the -1 subsite allows another docking position for the terminal sugar; i.e., one position is set up for catalysis, whereas the other is an intermediate stage prior to the displacement of water from the active site by the incoming sugar hydroxyls. The +1 subsite, an aromatic clamp , permits several different sugar positions and orientations, including a 180°flip that explains the observed variable regiospecificity. The p-nitrophenyl group on the acceptor most likely influences the unexpectedly observed β-1,6-specificity through its interaction with F229. These results demonstrate that tailoring the specificity of a particular glycosynthase depends not only on the chemical structure of the acceptor but also on understanding the structural basis of the promiscuity of the native enzyme.
Glycosynthases from Thermotoga neapolitana β-glucosidase 1A: A comparison of α-glucosyl fluoride and in situ-generated α-glycosyl formate donors
Pozzo, Tania,Plaza, Merichel,Romero-Garcia, Javier,Faijes, Magda,Karlsson, Eva Nordberg,Planas, Antoni
, p. 132 - 139 (2014/07/21)
TnBgl1A from the thermophile Thermotoga neapolitana is a dimeric β-glucosidase that belongs to glycoside hydrolase family 1 (GH1), with hydrolytic activity through the retaining mechanism, and a broad substrate specificity acting on β-1,4-, β-1,3- and β-1,6-linkages over a range of glyco-oligosaccharides. Three variants of the enzyme (TnBgl1A-E349G, TnBgl1A-E349A and TnBgl1A-E349S), mutated at the catalytic nucleophile, were constructed to evaluate their glycosynthase activity towards oligosaccharide synthesis. Two approaches were used for the synthesis reactions, both of which utilized 4-nitrophenyl β-d-glucopyranoside (4NPGlc) as an acceptor molecule: the first using an α-glucosyl fluoride donor at low temperature (35 °C) in a classical glycosynthase reaction, and the second by in situ generation of the glycosyl donor with (4NPGlc), where formate served as the exogenous nucleophile under higher temperature (70 °C). Using the first approach, TnBgl1A-E349G and TnBgl1A-E349A synthesized disaccharides with β-1,3-linkages in good yields (up to 61%) after long incubations (15 h). However, the GH1 glycosynthase Bgl3-E383A from a mesophilic Streptomyces sp., used as reference enzyme, generated a higher yield at the same temperature with both a shorter reaction time and a lower enzyme concentration. The second approach yielded disaccharides for all three mutants with predominantly β-1,3-linkages (up to 45%) but also β-1,4-linkages (up to 12.5%), after 7 h reaction time. The TnBgl1A glycosynthases were also used for glycosylation of flavonoids, using the two described approaches. Quercetin-3-glycoside was tested as an acceptor molecule and the resultant product was quercetin-3,4′-diglycosides in significantly lower yields, indicating that TnBgl1A preferentially selects 4NPGlc as the acceptor.
Glycosynthase with broad substrate specificity-an efficient biocatalyst for the construction of oligosaccharide library
Wei, Jinhua,Lv, Xun,Lue, Yang,Yang, Gangzhu,Fu, Lifeng,Yang, Liu,Wang, Jianjun,Gao, Jianhui,Cheng, Shuihong,Duan, Qian,Jin, Cheng,Li, Xuebing
, p. 2414 - 2419 (2013/05/23)
A versatile glycosynthase (TnG-E338A) with strikingly broad substrate scope has been developed from Thermus nonproteolyticus β-glycosidase (TnG) by using site-directed mutagenesis. The practical utility of this biocatalyst has been demonstrated by the facile generation of a small library containing various oligosaccharides and a steroidal glycoside (total 25 compounds) in up to 100 % isolated yield. Moreover, an array of eight gluco-oligosaccharides has been readily synthesized by the enzyme in a one-pot, parallel reaction, which highlights its potential in the combinatorial construction of a carbohydrate library that will assist glycomic and glycotherapeutic research. Significantly, the enzyme provides a means by which glycosynthase technology may be extended to combinatorial chemistry.
Isolation and characterization of a novel α-glucosidase with transglycosylation activity from Arthrobacter sp. DL001
Zhou, Kun,Luan, Hong-Wei,Hu, Ying,Ge, Guang-Bo,Liu, Xing-Bao,Ma, Xiao-Chi,Hou, Jie,Wang, Xiu-Li,Yang, Ling
experimental part, p. 48 - 57 (2012/09/07)
A strain of Arthrobacter sp. DL001 with high transglycosylation activity was successfully isolated from the Yellow Sea of China. To purify the extracellular enzyme responsible for transglycosylation, a four-step protocol was adopted and the enzyme with electrophoretical purity was obtained. The purified enzyme has a molecular mass of 210 kDa and displays a narrow hydrolysis specificity towards α-1,4-glucosidic bond. Its hydrolytic activity was identified as decreasing in the order of maltotriose > panose > maltose. Only 3.61% maltose activity occurs when p-nitrophenyl α-d-glycopyranoside serves as a substrate, suggesting that this enzyme belongs to the type II α-glucosidase. In addition, the enzyme was able to transfer glucosyl groups from the donors containing α-1,4-glucosidic bond specific to glucosides, xylosides and alkyl alcohols in α-1,4- or α-1,6-manners. A decreased order of activity was observed when maltose, maltotriose, panose, β-cyclodextrin and soluble starch served as glycosyl donors, respectively. When maltose was utilized as a donor and a series of p-nitrophenyl-glycosides as acceptors, the glucosidase was capable of transferring glucosyl groups to p-nitrophenyl-glucosides and p-nitrophenyl-xylosides in α-1,4- or α-1,6-manners. The yields of p-nitrophenyl-oligosaccharides could reach 42-60% in 2 h. When a series of alkyl alcohols were utilized as acceptors, the enzyme exhibited its transglycosylation activities not only to the primary alcohols but also to the secondary alcohols with carbon chain length 1-4. Therefore, all the results indicated that the purified α-glucosidase present a useful tool for the biosynthesis of oligosaccharides and alkyl glucosides.
Creation of an α-mannosynthase from a broad glycosidase scaffold
Yamamoto, Keisuke,Davis, Benjamin G.
, p. 7449 - 7453 (2012/09/21)
α-Mannosides made easy: Mutation of a family-GH31 α-glucosidase that displays plasticity to alterations at the 2-OH position of donor substrates created an efficient α-mannoside-synthesizing biocatalyst. A simple fluoride donor reagent was used for the synthesis of a range of mono-α-mannosylated conjugates using the α-mannosynthase displaying low (unwanted) oligomerization activity. Copyright
α-Glucosidase mutant catalyzes "α-glycosynthase"-type reaction
Okuyama, Masayuki,Mori, Haruhide,Watanabe, Kotomi,Kimura, Atsuo,Chiba, Seiya
, p. 928 - 933 (2007/10/03)
Replacement of the catalytic nucleophile Asp481 by glycine in Schizosaccharomyces pombe α-glucosidase eliminated the hydrolytic activity. The mutant enzyme (D481G) was found to catalyze the formation of an α-glucosidic linkage from β-glucosyl fluoride and
