Transglycosylation activity

In a more recent study (Asp et al. 1980), six oligosaccharides from hydrolyzed lactose milk which had been treated with K. lactis lactase were isolated from their structure, it was concluded that the enzyme had high transglycosylation activity with specificity for the formation of /3-(l,6)-galactosidic bonds. 

Figure 6. Transglycosylation activity of /3-glucosidase. The reaction mixture initially contained 3% cellobiose, 0.0009% (3-glucosidase, and 0.05M sodium acetate buffer, pH 5 0. Incubation was carried out at 45°C in a reciprocating shaker. Each sample was boiled for five minutes and analyzed by HPLC (Gt = glucose, G2 = cellobiose, Gs = trisaccharides.)...

Murata, T., Hattori, T., Amarume, S., Koichi, A. and Usui, T. (2003). Kinetic studies on endo-beta-galactosidase by a novel colorimetric assay and synthesis of N-acetyllactosamine-repeating oligosaccharide beta-glycosides using its transglycosylation activity. European Journal of Biochemistry, 270, 3709-3719. 

Kadowaki S, Saskiawan I, Watanabe J, Yamamoto K, Bunno M, Ichihara Y, Kumagai H. Transglycosylation activity of P-A-acetylhexosaminidase from Penicillium oxalicum and its application to synthesis of a drug carrier. J. Perm. Bioeng. 1997 83 341-345. 

Takegawa K, Yamaguchi S, Kondo A, Iwamoto H, Nakoshi M, Kato 1, Iwahara S. Transglycosylation activity of endo-beta-A-acetylglucosaminidase from Arthrobacter protophormiae. Biochem. Int. 1991 24 849-855. 

Yamamoto K, Kadowaki S, Watanabe J, Kumagai H. Transglycosylation activity of Mucor hiemalis endo-beta-A-acetyl-glucos-aminidase which transfers complex oligosaccharides to the N-acetylglucosamine moieties of peptides. Biochem. Biophys. Res. Commun. 1994 203 244-252. 

Fujita M, Shoda S, Haneda K, Inazu T, Takegawa K, Yamamoto K. A novel disaccharide substrate having 1,2-oxazoline moiety for detection of transglycosylating activity of endogly-cosidases. Biochim. Biophys. Acta. 2001 1528 9-14. 

The transfructosylation activity of this enzyme is strongly dependent on pH and the substrate concentration. Some glycosidases are known to be more hydrolytically active under acidic conditions, whereas their transglycosylation activity is higher at pH values above their pH optimum. Transfructosylation of... 

When xylobiose was tested as a substrate, deviation from Michaelis-Menten kinetics consistent with transglycosylation activity was observed at higher substrate concentrations (up to 16 mM xylobiose was tested). Capillary electrophoresis analysis of the reaction products from xylobiose hydrolysis showed production of significant xylose and xylotriose, corroborating the transglycosylation activity inferred by the kinetic data. Thus, under the... 

Transglycosylation activity was enhanced by preparing the chimeric enzyme The activity of the Tm3Cg chimera was at a level twice that observed with the Tm enzyme no activity was observed in Cg (Figure 15.5). 

FIGURE 15.5 Transglycosylation activity of chimeric enzymes. Relative rates of / -nitro-phenol production from pNP-P-o-glucopyranoside were measured in the presence of a series... 

As shown in Figure 1, the enzymatic transglycosylation and hydrolysis are a competing process. The efficiency to form a new oligosaccharide or glycoconjugate by the enzymatic reaction depends on the intrinsic transglycosylation activity of the endoglycosidase and on the control of the... 

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