Synthesis of isomaltooligosaccharides using 4-O-α-d-isomaltooligosaccharylmaltooligosaccharide 1,4-α-isomaltooligosaccharohydrolase.

Isomaltooligosaccharides (IMOs), including isomaltose, are valuable oligosaccharides, and the development of methods to synthesize high-purity IMOs has long been underway. We recently discovered a novel enzyme, 4-O-α-d-isomaltooligosaccharylmaltooligosaccharide 1,4-α-isomaltooligosaccharohydrolase (IMM-4IH), that showed promise for improving the synthesis process. In this study, we establish methods for synthesizing isomaltose and IMOs consisting of a variety of degrees of polymerization from starch using IMM-4IH.

Cloning and sequence analysis of 4-O-α-d-isomaltooligosaccharylmaltooligosaccharide 1,4-α-isomaltooligosaccharohydrolase from Sarocladium kiliense U4520.

A novel enzyme, 4-O-α-d-isomaltooligosaccharylmaltooligosaccharide 1,4-α-isomaltooligosaccharohydrolase (IMM-4IH), was previously discovered from Sarocladium kiliense U4520. In order to identify the factors underlying the unique substrate specificity of IMM-4IH, we endeavored to determine the amino acid sequence of the enzyme. By comparing the partial amino acid sequence of the enzyme to whole genome sequencing data of S.

Discovery of a novel glucanohydrolase, 4-α-isomaltooligosylglucose 4-glucanohydrolase, that can be used for efficient production of isomaltose.

We discovered a novel enzyme in our pursuit of an improved method for the production of isomaltose. The enzyme, 4-α-isomaltooligosylglucose 4-glucanohydrolase from Sarocladium kiliense U4520, recognizes the panose motif (α-d-Glcp-(1 → 6)-α-d-Glcp-(1 → 4)-d-Glcp) and hydrolyzes the α-1,4-glucosidic bond on the reducing end side with respect to the α-1,6-glucosidic bond. The structure on the non-reducing end of the panose motif is important for the recognition of the substrate by the enzyme, and the substrate specificity is unique and distinguished from previously reported enzymes.

Cloning of the cycloisomaltotetraose-forming enzymes using whole genome sequence analyses of Agreia sp. D1110 and Microbacterium trichothecenolyticum D2006.

We performed whole genome sequence analyses of Agreia sp. D1110 and Microbacterium trichothecenolyticum D2006 that secrete enzymes to produce cyclo-{→6)-α-d-Glcp-(1→6)-α-d-Glcp-(1→6)-α-d-Glcp-(1→6)-α-d-Glcp-(1→} (CI4) from dextran. Full-length amino acid sequences of CI4-forming enzymes were identified by matching known N-terminal amino acid sequences with products of the draft genome.

Efficient production of isomaltose and isomaltooligosaccharides from starch using 1,4-α-glucan 6-α-glucosyltransferase and isopullulanase.

We attempted to develop an efficient method for producing isomaltose, a disaccharide consisting of an α-(1→6)-linkage, from starch by combining enzymes of known activity. We found that the combination of 1,4-α-glucan 6-α-glucosyltransferase from Bacillus globisporus N75 and isopullulanase from Aspergillus brasiliensis ATCC 9642 led to the efficient synthesis of isomaltose. Inclusion of isoamylase and cyclomaltodextrin glucanotransferase resulted in increased efficiency, with production yields exceeding 70%.

Purification and characterization of cycloisomaltotetraose-forming glucanotransferases from Agreia sp. D1110 and Microbacterium trichothecenolyticum D2006.

Glucanotransferases that can synthesize cyclo-{→6)-α-d-Glcp-(1→6)-α-d-Glcp-(1→6)-α-d-Glcp-(1→6)-α-d-Glcp-(1→} (CI4) from dextran were purified to homogeneity from the culture supernatant of Agreia sp. D1110 and Microbacterium trichothecenolyticum D2006. The molecular mass of both enzymes was estimated to be 86 kDa by SDS-PAGE.