Abstract
The venom of Agkistrodon halys blomhofii (Mamushi) contains three proteinases. These
proteinases could be separated on DEAE-cellulose, and were designated as proteinases a, b and c. These proteinases have different pH optima: the values were 10.5, 9.8 and 8.9 for proteinases a, b and c, respectively. They showed different stability against heating or treatment with cysteine, and proteinase c was the most unstable. These proteinases were activated by Ca++ and Mg++, but were inhibited by other divalent metal ions. All of these were inhibited by EDTA. From the results of exhaustive digestion of casein and muramidase it was considered that these proteinases have different substrate specificities from each other. During the chromato-graphic fractionation of these proteinases, BAEE hydrolyzing activity was found to be separable from proteinase activity, at least from proteinases b and c.
The authors wish to express their thanks to Mr. S. Kawachi of Hoshi College of Pharmacy for his valuable help in this work. Thanks are also due to Dr. S. Iwanaga, T. Omori, T. Sato, and Y. Mizu-shima of this laboratory for their help in this work. This work was supported, in part, by a grant for scientific researches from the Ministry of Education for “Enzymatic studies on animal toxins, ” to which our thanks are due.
