Saturation behavior of superoxide dismutation catalyzed by the iron containing superoxide dismutase of E. coli B.
نویسندگان
چکیده
The iron containing superoxide dismutase from E. coli B is shown to catalyze superoxide dismutation by a mechanism which exhibits saturation kinetics. This behavior is quite different from that observed previously with bovine Zn/Cuand iron-containing superoxide dismutase from P. leiosnathi. Two parameters of catalysis were measured in the pH range 7.2 to 10.4: k was found to be independent of pH and Km varied with the function Km = K~ow pH) [i + exp(pH 8.8)]. These results implicate a group in the catalytic mechanism which ionizes with pKa = 8.8.
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عنوان ژورنال:
- Biochemical and biophysical research communications
دوره 100 1 شماره
صفحات -
تاریخ انتشار 1981