Amylases and related glycoside hydrolases with transglycosylation activity used for the production of isomaltooligosaccharides

Abstract

Isomaltooligosaccharides (IMOS) are sugars with health promoting properties that make them relevant for the pharmaceutical and food industries. IMOS have ample chemical diversity achieved by different α-glucosidic linkages and polymerization degrees, forming linear, branched and cyclic structures. Enzymatic synthesis of these compounds can be carried out by glycoside hydrolases (GHs) with transglycosylating activity. Different substrates are used for the synthesis: combinations of disaccharides and monosaccharides, or polymeric carbohydrates such as starch or dextran, which are converted to IMOS by a combination of hydrolysis and transglucosylation. In this review, the structural features of different enzyme families (GH31, GH13, GH70, GH57 and GH66) involved in IMOS synthesis are analysed. Focus is placed on structural traits that affect substrate and product specificity, and on the relative efficiency of transglucosylation and hydrolysis. Information resulting from site-directed mutagenesis and sequence alignments complements structural data to understand the role of specific residues in the performance of the enzymes. Altogether, these studies provide a frame of knowledge which may be used to design new enzymes with improved properties

Characterization of a Maltase from an Early-Diverged Non-Conventional Yeast Blastobotrys adeninivorans

“…By 24 h of reaction with 500 mM maltose, the amount of transglycosylation products was 12.6% of total sugars in the reaction mixture, while the respective value for the MAL62 protein was about three times less-4.5% (see Table S3). Many α-glucosidases can transglycosylate and produce short oligosaccharides, especially at high concentration of the substrate [17][18][19][20][21]. We assayed this possibility by incubating BaAG2 with 250 and 500 mM maltose up to 72 h and analyzed the reaction products by HPLC.…”

“…α-Glucosidases have been popular objects to study protein evolution and phylogenesis [13][14][15][16], but they also have a biotechnological value. Thus, some of them have a high transglycosylating activity thanks to which they produce prebiotic oligosaccharides and potential functional food ingredients such as panose, melezitose, isomelezitose and isomalto-oligosaccharides [17][18][19][20][21]. For example, the α-glucosidase of S. cerevisiae produced isomelezitose from sucrose when the substrate concentration was high [21].…”

Structure‐Specific Fermentation of Galacto‐Oligosaccharides, Isomalto‐Oligosaccharides and Isomalto/Malto‐Polysaccharides by Infant Fecal Microbiota and Impact on Dendritic Cell Cytokine Responses

“…[ 7 , 26 ] IMO are produced from starch using enzymes from diverse glycosyl hydrolase (GH) families. [ 27 ] The enzymes exhibit transferase, hydrolytic or branching activity, which results in a mixture of α‐linked gluco‐oligomers varying in type of glycosidic linkage and DP (2–10). [ 27 , 28 ] Production technologies used nowadays differ in the number and type of enzymes used, which results in the production of structurally distinct IMO preparations.…”

Novel cold-adapted raw-starch digesting α-amylases from Eisenia fetida: Gene cloning, expression, and characterization

“…5 ). It is reported that amylases belonging to GH 13 react the transglycosylastion [25] . It is indicated that Ef-Amy I and II may also react with transglycosylation.…”