期刊名称：Journal of Nutritional Science and Vitaminology
印刷版ISSN：0301-4800
电子版ISSN：1881-7742
出版年度：1979
卷号：25
期号：1
页码：33-41
DOI：10.3177/jnsv.25.33
出版社：Center for Academic Publications Japan
摘要：In order to clarify the function of the carbohydrate moiety of bovine κ-casein, κ-casein components having different carbohydrate contents were prepared by DEAE-cellulose chromatography. Five adsorbed fractions so obtained had an identical peptide chain and contained carbohydrate moieties of increasing size in the order of components P-2, P-3, P-4, P-5 and P-6. The susceptibility of κ-casein components, having different carbohydrate contents, to various proteases was examined. κ-Casein components were subjected to calf rennin [chymosin; EC 3.4.23.4], bovine trypsin [EC 3.4.21.4], α-chymotrypsin [EC 3.4.21.1], pronase [EC 3.4.24.4] and human plasmin [EC 3.4.21.7]. The component containing a larger carbohydrate moiety was less susceptible to hydrolysis than the component containing a smaller carbohydrate moiety. Rennin, trypsin, α-chymotrypsin and pronase hydrolyzed each component with a different reaction rate. On the contrary, human plasmin hydrolyzed component P-2, but did not hydrolyze component P-5. These results indicate that the carbohydrate moiety of κ-casein affected the suscepti-bility of κ-casein components to various proteases.
