| 摘要 |
Glycosylated acceptors are prepared using glycosyl transferase and activated glycosyl derivatives as donor sugars without the use of sugar nucleotides as donor sugars. A reaction mixture composition containing an activated glycoside derivative such as glycosyl fluoride or glycosyl mesylate, an acceptor substrate such as lactose or other oligosaccharide, a glycosyl transferase and a catalytic amount of a nucleotide phosphate or nucleotide phosphate analog is reacted to produce the glycosylated acceptor. The acceptor substrate may also be a monosaccharide, a fluorescent-labeled saccharide or a saccharide derivative such as an aminoglycoside antibiotic. The glycosyl transferase may be immobilized by removing its membrane-binding domain and attaching in its place a cellulose-binding domain. In another embodiment, a glycosylated acceptor is formed by making a nucleotide phosphate glycoside in situ in a steady state concentration. This process is carried out by admixing in an aqueous medium an activated glycoside derivative, a glycosyl transferase, a member selected from the group consisting of a nucleotide phosphate and a nucleotide phosphate analog, a nucleotide phosphate sugar-dependent enzyme and an acceptor substrate. The glycosyl transferase catalyzes the reaction of the activated glycoside derivative with the nucleotide phosphate or analog to form the nucleotide phosphate glycoside in situ, and the nucleotide phosphate sugar-dependent enzyme catalyzes the reaction of the nucleotide phosphate glycoside with the acceptor substrate to form the glycosylated acceptor. |
