Mutant glycosidases in which the amino acid in the active site that serves as the acid, base or acid/base-catalyst is converted from a carboxylic acid to some other amino acid (for example to a simple alkyl, as in alanine or glycine) can catalyze the reaction of a thiosugar acceptor and an activated donor to form a thioglycoside. The “thioglycoligases” represent a novel class of mutant enzymes, and represent a first aspect of the invention. Thioglycoligases can be used in accordance with the method of the invention to couple a thiosugar acceptor and an activated donor to form a thioglycoside. By selection of the donor and acceptor species, as well as the specific enzyme employed, thioglycosides of different structure and stereochemistry can be obtained.
突变的糖苷酶中,活性位点中作为酸、碱或酸碱催化剂的
氨基酸从
羧酸转变为其他
氨基酸(例如转变为简单的烷基,如丙
氨酸或甘
氨酸),可以催化
硫代糖受体和活化供体的反应,形成
硫代糖苷。 "
硫代糖聚合酶"代表一类新型突变酶,并代表本发明的第一个方面。可以根据本发明的方法使用
硫代糖聚合酶将
硫代糖受体和活化供体偶联形成
硫代糖苷。通过选择供体和受体物种以及特定的酶,可以获得不同结构和立体
化学的
硫代糖苷。