Yutaka T, Okada S, Mimaki K, Sugita T, Yabuuchi H
Clin Chim Acta. 1975 Mar 24;59(3):283-90. doi: 10.1016/0009-8981(75)90003-0.
Two types of GM-1 gangliosidosis were studied biochemically. Type 1 liver accumulated non-lipid hexosamine in addition to GM-1 ganglioside, but there was no increase of hexosamine and GM-1 in type 2 liver. The optimum pH of liver beta-galactosidase of type 1 and type 2 was 5--6 while that of the normal control was 4.5. Type 1 brain beta-galactosidase showed a slightly acidic optimum pH, i.e. 4.0 in comparison with that of the normal control. The optimum pH of type 2 brain beta-galactosidase was 5.5, like the liver enzyme. The thermostability of liver beta-galactosidase was the same in type 1 and type 2, while that of brain was different. Beta-galactosidase of type 1 and type 2 liver is more stable at 42 degrees C than the normal control, but a different thermostability was observed in type 1 and type 2 brain. Liver beta-galactosidase of type 1 showed one peak each at acid and neutral pH, and type 2 liver had only one peak at neutral pH.
对两种类型的GM-1神经节苷脂沉积病进行了生化研究。1型肝脏除了积累GM-1神经节苷脂外，还积累非脂质己糖胺，但2型肝脏中己糖胺和GM-1没有增加。1型和2型肝脏β-半乳糖苷酶的最适pH值为5-6，而正常对照的最适pH值为4.5。1型脑β-半乳糖苷酶显示出略呈酸性的最适pH值，即与正常对照相比为4.0。2型脑β-半乳糖苷酶的最适pH值为5.5，与肝脏酶相同。1型和2型肝脏β-半乳糖苷酶的热稳定性相同，而脑β-半乳糖苷酶的热稳定性不同。1型和2型肝脏的β-半乳糖苷酶在42℃时比正常对照更稳定，但在1型和2型脑中观察到不同的热稳定性。1型肝脏β-半乳糖苷酶在酸性和中性pH值下各有一个峰，2型肝脏在中性pH值下只有一个峰。
