Docherty P A, Aronson N N
Biochim Biophys Acta. 1987 Aug 21;914(3):283-8. doi: 10.1016/0167-4838(87)90287-1.
The compound alpha-D-mannopyranosylmethyl-p-nitrophenyltriazene (alpha-ManMNT) has been tested for its effect on four alpha-D-mannosidase activities present in rat liver. When p-nitrophenyl alpha-D-mannopyranoside was used as a substrate, preincubation of enzyme with 1.0 mM alpha-ManMNT inhibited soluble alpha-D-mannosidase by 90%, lysosomal alpha-D-mannosidase by approx. 60%, and had virtually no effect on Golgi mannosidase II. Golgi mannosidase I removal of the four alpha-1,2-linked D-mannoses from the common Man9GlcNAc2 oligosaccharide structure formed during N-linked glycoprotein biosynthesis was also blocked by treatment of the Golgi fraction with this compound. Mannosyltriazene inhibition of the three susceptible hepatic alpha-D-mannosidases was largely irreversible. alpha-ManMNT should therefore be useful for studying oligosaccharide processing and possibly for determining the turnover time of the inhibited alpha-D-mannosidases.
化合物α-D-甘露吡喃糖基甲基对硝基苯基三氮烯（α-ManMNT）已被测试其对大鼠肝脏中四种α-D-甘露糖苷酶活性的影响。当对硝基苯基α-D-甘露吡喃糖苷用作底物时，酶与1.0 mMα-ManMNT预孵育可使可溶性α-D-甘露糖苷酶抑制90%，溶酶体α-D-甘露糖苷酶抑制约60%，而对高尔基体甘露糖苷酶II几乎没有影响。在N-连接糖蛋白生物合成过程中形成的常见Man9GlcNAc2寡糖结构中，高尔基体甘露糖苷酶I去除四个α-1,2-连接的D-甘露糖的过程也会被用该化合物处理高尔基体部分所阻断。甘露糖基三氮烯对三种敏感的肝脏α-D-甘露糖苷酶的抑制作用在很大程度上是不可逆的。因此，α-ManMNT应有助于研究寡糖加工，并且可能有助于确定被抑制的α-D-甘露糖苷酶的周转时间。
