Paus E
Eur J Biochem. 1977 Feb 15;73(1):155-61. doi: 10.1111/j.1432-1033.1977.tb11302.x.
Both alpha-mannosidases I and II from Phaseolus vulgaris have molecular weights about 210000-220000 and contain approximately 2 mol zinc/mol protein. alpha-Mannosidase I seems to consist of more glutamic acid than alpha-mannosidase II, while the latter is richer in serine. They are glycoproteins: alpha-mannosidase I contains 8.3% carbohydrate by weight while alpha-mannosidase II contains 16.5%. This enzyme form shows a greater thermal stability than alpha-mannosidase I. The structure of alpha-mannosidase has been investigated by equilibrium sedimentation analysis in guanidine hydrochloride, electrophoresis in dodecylsulphate, and alkaline electrophoresis after exposure to high pH. The protein appears to be composed of two non-covalently bound subunits of molecular weights about 110000. Electron micrographs revealed images of molecules that consisted of two rod-shaped monomers of roughly square cross-sections 4.2 X 4.2 nm. Each rod was about 7.4 nm long. The monomers seemed parallell along the long axis.
菜豆中的α-甘露糖苷酶I和II的分子量均约为210000 - 220000，每摩尔蛋白质约含2摩尔锌。α-甘露糖苷酶I似乎比α-甘露糖苷酶II含有更多的谷氨酸，而后者富含丝氨酸。它们是糖蛋白：α-甘露糖苷酶I含8.3%（重量）的碳水化合物，而α-甘露糖苷酶II含16.5%。这种酶形式比α-甘露糖苷酶I表现出更高的热稳定性。通过在盐酸胍中进行平衡沉降分析、在十二烷基硫酸盐中进行电泳以及在暴露于高pH后进行碱性电泳，对α-甘露糖苷酶的结构进行了研究。该蛋白质似乎由两个分子量约为110000的非共价结合亚基组成。电子显微镜照片显示分子图像由两个横截面大致为4.2×4.2纳米的方形杆状单体组成。每个杆长约7.4纳米。单体似乎沿长轴平行排列。
