Carbohydrate Epimeraseの触媒作用，構造，その応用例

More than 20 types of carbohydrate epimerase have been reported to date. Distinctly different en- zymes recognize the C1, C2, C3, C4, C5 or C6 position of carbohydrate substrates. They include, for instance, aldose 1-epimerase, N-acetyl-D-glucosamine 2-epimerase, UDP-N-acetylglucosamine 2-epimerase, cellobiose 2- epimerase, D-ribulose-5-phosphate 3-epimerase, L-ribulose-5-phosphate 4-epimerase, UDP-galactose 4- epimerase, dTDP-6-deoxy-D-xylo-4-hexulose 3,5-epimerase, GDP-mannose 3,5-epimerase and ADP-L-glycero-D- mannoheptose 6-epimerase. Their biological properties, catalytic mechanisms and tertiary structures are very diverse. This review focuses on the catalysis, structures and applications of carbohydrate epimerases that have recently been characterized in detail.