Examples of kinetically controlled transglycosylation reactions

Round bottomed flask (10 ml) with rubber septum 

HPLC (Shimadzu LC-6AD liquid chromatograph fitted with a YMC-GEL ODS-M 120 S-5 column, 20 X 250 mm) 

Special precautions. There are no reported risks associated with the P-galactosidase from E. coli, however, many enzymes are immunogenic, so avoid skin contact and inhalation of enzyme powders. Safety glasses and gloves should be worn during this experiment. 

Notes and discussion. This method describes the use of (3-A-acetylhexosaminidase from A. oryzae. A mixture of the (3-(l — 4) (major) and (3-(l — 6) (minor) adducts plus reverse hydrolysis products are produced. However, incubation with (3-A-acetylhexosaminidase from Jack beans (Canavalia ensiformis) selectively hydrolyses the (3-(l 6) product and the reverse hydrolysis products to yield the pure (3-(l 4)-disaccharide. This method illustrates how the specificities and activities of different glycosidases can be combined to create the desired regioisomer. A full procedure for carbon-Cellte chromatography of monosaccharides from disaccharides and higher oligomers is given [30]. 

Round bottomed flask (50 ml) with rubber septum Syringes (1 and 10 ml) and needles Water bath HPLC equipment 

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