Purification, properties, and industrial significance of transglucosidase from Aspergillus niger

Novel α-Glucosidase from Aspergillus nidulans with Strong Transglycosylation Activity

“…The A. niger enzyme possesses strong transglycosylation activity, however, a maltose concentration of 30% is used for A. niger ␣-glucosidase to achieve an isomaltose content of 30% in the final reaction products (3,21). At a substrate concentration of 0.5%, AgdB clearly showed higher transglycosylation activity than that of the A. niger enzyme (15). The other ␣-glucosidases so far reported also require high substrate concentrations to exhibit sufficient transglycosylation activities (13).…”

“…Theoretically ␣-glucosidase is capable of catalyzing transglycosylation, since it is a retaining glycosyl hydrolase (GH) (2), and some ␣-glucosidases indeed exhibit clear transglycosylation activity. For example, Aspergillus niger ␣-glucosidase catalyzes formation of ␣-1,6 glucosidic linkages in addition to hydrolysis, resulting in production of isomaltose (6-O-␣-D-glucopyranosyl-D-glucopyranose) and panose (6-O-␣-glucopyranosyl-maltose) from maltose (3,15,21). Buckwheat ␣-glucosidase produces kojibiose (2-O-␣-glucosyl-glucose), nigerose (3-O-␣-glucosyl-glucose), maltose, and isomaltose from soluble starch (1), and ␣-glucosidases from Bacillus stearothermophilus and brewer's yeast produce oligosaccharides consisting of ␣-1,3, ␣-1,4, and ␣-1,6 linkages (13).…”

“…At 6 h of the reaction, approximately 50% of maltose was converted to transglycosylation products, 60% of which was found to be isomaltose. Formation of isomaltose and panose from maltose by the action of ␣-glucosidase has been demonstrated in A. niger and A. oryzae (3,15,(20)(21)(22). The A. niger enzyme possesses strong transglycosylation activity, however, a maltose concentration of 30% is used for A. niger ␣-glucosidase to achieve an isomaltose content of 30% in the final reaction products (3,21).…”

Substrate Specificity and Subsite Affinities of Crystalline .ALPHA.-Glucosidase from Aspergillus niger.

“…The three subsites were considered to be effective for the binding of substrate. 18) It seems worthwhile…”

Construction of an Engineering Strain Producing High Yields of α-TransglucosidaseviaAgrobacterium tumefaciens-Mediated Transformation ofAsperillus niger

“…[4][5][6] -Transglucosidase (EC 3.2.1.20) is a group of enzymes that catalyze the hydrolysis of -glucosidic linkages from the non-reducing terminal of substrates releasing -glucose or transferring a glucosyl residue to the 6-OH of the accepting glucose unit, yielding isomaltooligosaccharide (IMO). 7,8) It is widely distributed in microorganisms, animals, and plants. Since an -transglucosidase-producing strain was selected by Hayashibara Biochemical Laboratories in 1982, it has been widely used in the food industry and has attracted much attention.…”