Lorentz K
Enzyme. 1982;28(4):233-41. doi: 10.1159/000459107.
alpha-Amylases from human urine, pancreas, and saliva were purified to homogeneity. Their molecular and catalytic properties were similar with respect to relative molecular masses, stability, and absorbance in neutral solution, but their isoelectric points differed clearly. Salivary amylase was more sensitive than the other two to inhibition by iodoacetate and EDTA, suggesting a less compact structure. The intermediate qualities of the urinary activity were ascribed to the fact that this enzyme originates from other two without major modifications by metabolism. Human alpha-amylase should be considered as a sole enzyme with multiple forms originating from glycosylation and deamidation. There was no evidence for real isoenzymes.
从人尿液、胰腺和唾液中纯化出的α-淀粉酶达到了均一性。它们在相对分子质量、稳定性和中性溶液中的吸光度方面，分子和催化特性相似，但它们的等电点明显不同。唾液淀粉酶比其他两种淀粉酶对碘乙酸盐和乙二胺四乙酸（EDTA）的抑制更敏感，这表明其结构不那么紧密。尿液中该酶活性的中间性质归因于这样一个事实，即这种酶源自其他两种酶，且未经过代谢的重大修饰。人α-淀粉酶应被视为一种单一的酶，有多种因糖基化和脱酰胺作用产生的形式。没有证据表明存在真正的同工酶。
