N-乙酰-D-神经氨酸醛缩酶的克隆、表达和活性测定

N-乙酰-D-神经氨酸是一类特殊的氨基糖的重要代表，有重要的医药应用价值。本文从大肠埃希氏菌中克隆N-乙酰-D-神经氨酸醛缩酶基因，并得到高效表达的醛缩酶。经纯化后催化活性实验结果表明，醛缩酶可将N-乙酰-D-甘露糖胺高效率地转化为N-乙酰-D-神经氨酸，表现出较高的催化活性。本工作为N-乙酰-D-神经氨酸酶的大规模催化合成奠定了基础。

Cloning,expression and biological activity determination of N-acetyl-D-neuraminic acid aldonase from E.coli

N-acetyl-D-neuraminic acid is an important representative of a distinct class of aminosugar compounds-neuraminic acid, and has potential commercial value. N-acetyl-D-neuraminic acid aldonase from E.coli was cloned, expressed in high amount and purified to high homogeneity using affinity column method. The enzyme activity test results showed that aldonase could transform Nacetyl-D-ManNAc into N-acetyl-D-neuraminic acid very efficiently. This work has layed a sound foundation for the large scale catalytic synthesis of N-acetyl-D-neuraminic acid.