【摘 要】
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Enzymes that cleave glycosidic bonds are widely investigated in carbohydrate metabolism[1].Biochemical,biophysical,and genetic studies suggest that these en
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Enzymes that cleave glycosidic bonds are widely investigated in carbohydrate metabolism[1].Biochemical,biophysical,and genetic studies suggest that these enzymes cleave glycosidic bonds by a largely dissociative mechanism generating an oxocarbenium ion intermediate[2-3].We have examined the fully mechanism of glycosidic cleavage with density functional theory by B3LYP method at 6-31g(d,p)basis level.The results indicate that this reaction experiences a hemiaminal intermediate,which could lose a molecule of water directing to an imine compound.Otherwise,the cyclization of hemiaminal intermediate will leads to the target products after elimination of two molecules of water.
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