Alpha-Isomaltosylglucosaccharide synthase, process for producing the same and use thereof

摘要

The object of the present invention is to provide an alpha-isomaltosylglucosaccharide-forming enzyme, process of the same, cyclotetrasaccharide, and saccharide composition comprising the saccharide which are obtainable by using the enzyme; and is solved by establishing an alpha-isomaltosylglucosaccharide-forming enzyme which forms a saccharide, having a glucose polymerization degree of at least three and having both the alpha-1,6 glucosidic linkage as a linkage at the non-reducing end and the alpha-1,4 glucosidic linkage other than the linkage at the non-reducing end, by catalyzing the alpha-glucosyl-transfer from a saccharide having a glucose polymerization degree of at least two and having the alpha-1,4 glucosidic linkage as a linkage at the non-reducing end without substantially increasing the reducing power; alpha-isomaltosyl-transferring method using the enzyme; method for forming alpha-isomaltosylglucosaccharide; process for producing a cyclotetrasaccharide having the structure of cyclo{->6)-alpha-D-glucopyranosyl-(1->3)-alpha-D-glucopyranosyl-(1->6)-alpha-D-glucopyranosyl-(1->3)-alpha-D-glucopyranosyl-(1->} using both the alpha-isomaltosylglucosaccharide-forming enzyme and the alpha-isomaltosyl-transferring enzyme; and the uses of the saccharides obtainable therewith.