UDP-glucosyltransferase mutant and application thereof

The invention belongs to the technical field of genetic engineering and biological catalysis, and particularly relates to a UDP-glucosyltransferase mutant and application thereof. The mutant is obtained by mutating a UDP-glucosyltransferase amino acid sequence as shown in SEQ ID NO.2 through at least one of the following mutations: mutating leucine at the 61 < th > site into methionine, mutating asparagine at the 87 < th > site into leucine, mutating glutamine at the 129 < th > site into phenylalanine, mutating serine at the 139 < th > site into alanine, the enzyme activity of the mutant is obviously higher than that of a wild type. The UDP-glucosyltransferase mutant is applied to preparation of Reb D, and the conversion rate is high. 本发明属于基因工程和生物催化技术领域，具体涉及UDP-葡萄糖基转移酶突变体及其应用。所述突变体是将如SEQ ID NO.2所示的UDP-葡萄糖基转移酶氨基酸序列经以下至少一种突变情况所得：将第61位的亮氨酸突变为甲硫氨酸，将第87位的天冬酰胺突变为亮氨酸，将第129位的谷氨酰胺突变为苯丙氨酸，将第139位的丝氨酸突变为丙氨酸，所述突变体酶活性均明显高于野生型。所述UDP-葡萄糖基转移酶突变体应用于制备Reb D，转化率较高。