VERFAHREN UND ZUSAMMENSETZUNGEN FÜR OLIGOSACCHARIDE SYNTHESE UND ANWENDUNG VON MUTANT GLYKOSIDASE

摘要

Mutant glycosidase enzymes are formed in which the normal nucleophilic amino acid within the active site has been changed to a non-nucleophilic amino acid. These enzymes cannot hydrolyze disaccharide products, but can still form them. Using this enzyme, oligoeaccharides are synthesized by preparing a mixture of an alpha -glycosol fluoride and a glycoside acceptor molecule; enzymatically coupling the alpha -glycosol fluoride to the glycoside acceptor molecule to form a glycosol glycoside product using the mutant glycosidase enzyme; and recovering the glycosyl product. The enzymes to be used are mutant forms of human or porcine alpha -amylase or yeast alpha -glucosidose having two catalytically active amino acids with carboxylic acid side claims within the active site, in the wild-type enzyme, with one of these amino acids being replaced by a different amino acid.