The hydrolysis of uridine cyclic phosphonate catalyzed by ribonuclease-A: implications for the mechanism of action of the enzyme.
نویسندگان
چکیده
Uridine 2',3'-cyclic phosphonate (I) is slowly hydrolyzed by ribonuclease-A with k(2) and K(m) values at pH6 that are respectively 1900 and 15 times smaller than the same parameters at the same pH for the related phosphate (II). Since the ratio of rate constants for hydroxide ion catalyzed hydrolysis is about 4, this result is consistent with, but does not prove a mechanism for the enzymic reaction that requires a pseudorotation.
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ورودعنوان ژورنال:
- Proceedings of the National Academy of Sciences of the United States of America
دوره 63 2 شماره
صفحات -
تاریخ انتشار 1969