13382-86-0Relevant articles and documents
Heterologous expression of a thermostable α-glucosidase from Geobacillus sp. Strain HTA-462 by Escherichia coli and its potential application for isomaltose–oligosaccharide synthesis
Zhang, Fan,Wang, Weiyang,Bah, Fatoumata Binta Maci,Song, Chengcheng,Zhou, Yifa,Ji, Li,Yuan, Ye
, (2019/05/02)
Isomaltose–oligosaccharides (IMOs), as food ingredients with prebiotic functionality, can be prepared via enzymatic synthesis using α-glucosidase. In the present study, the α-glucosidase (GSJ) from Geobacillus sp. strain HTA-462 was cloned and expressed in Escherichia coli BL21 (DE3). Recombinant GSJ was purified and biochemically characterized. The optimum temperature condition of the recombinant enzyme was 65 ?C, and the half-life was 84 h at 60 ?C, whereas the enzyme was active over the range of pH 6.0–10.0 with maximal activity at pH 7.0. The α-glucosidase activity in shake flasks reached 107.9 U/mL and using 4-Nitrophenyl β-D-glucopyranoside (pNPG) as substrate, the Km and Vmax values were 2.321 mM and 306.3 U/mg, respectively. The divalent ions Mn2+ and Ca2+ could improve GSJ activity by 32.1% and 13.8%. Moreover, the hydrolysis ability of recombinant α-glucosidase was almost the same as that of the commercial α-glucosidase (Bacillus stearothermophilus). In terms of the transglycosylation reaction, with 30% maltose syrup under the condition of 60 ?C and pH 7.0, IMOs were synthesized with a conversion rate of 37%. These studies lay the basis for the industrial application of recombinant α-glucosidase.
Branched alpha-glucan, alpha-glucosyltransferase which forms the glucan, their preparation and uses
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Page/Page column 18-19, (2010/06/11)
The present invention has objects to provide a glucan useful as water-soluble dietary fiber, its preparation and uses. The present invention solves the above objects by providing a branched α-glucan, which is constructed by glucose molecules and characterized by methylation analysis as follows: (1) Ratio of 2,3,6-trimethyl-1,4,5-triacetyl-glucitol to 2,3,4-trimethyl-1,5,6-triacetyl-glucitol is in the range of 1:0.6 to 1:4;(2) Total content of 2,3,6-trimethyl-1,4,5-triacetyl-glucitol and 2,3,4-trimethyl-1,5,6-triacetyl-glucitol is 60% or higher in the partially methylated glucitol acetates;(3) Content of 2,4,6-trimethyl-1,3,5-triacetyl-glucitol is 0.5% or higher but less than 10% in the partially methylated glucitol acetates; and(4) Content of 2,4-dimethyl-1,3,5,6-tetraacetyl-glucitol is 0.5% or higher in the partially methylated glucitol acetates; a novel α-glucosyltransferase which forms the branched α-glucan, processes for producing them, and their uses.
Research on the strong transglycosylation activity in Aspergillus niger
Yu, Lan,Zhang, Yun-Kai,Qin, Yong-Ling,Liu, Yu-Yan,Liang, Zhi-Qun
experimental part, p. 749 - 751 (2009/05/09)
Aspergillus niger M-1 strain shows strong transglycosylation activity. A gene of it was introduced into Escherichia coli, and isomalto-oligosaccharides were isolated by a chemical enzymatic method in order to measure the transglycosylation activity.