Magnetic circular dichroism of cobalt-copper and zinc-copper bovine superoxide dismutase.
نویسندگان
چکیده
The magnetic circular dichroism of the d-d transitions of Co(I1) when substituted for Zn(I1) in the Zn(II)-Cu(I1) enzyme bovine superoxide dismutase enzyme is reported. Magnetic circular dkhroism of the Co(I1) chromophore in the Co(II)-Cu(I1) enzyme is typical of tetrahedral Co(I1) compounds. The magnetic circular dichroism band pattern is almost identical with the magnetic circular dichroism of the anion complexes of Co(I1) carbonic anhydrase, implying similar coordination geometries in the two enzyme Co(I1) complexes. The Cu(I1) chromophore is only weakly induced by the magnetic field, with induced ellipticity an order of magnitude less than that of the Co(I1) chromophore. Reduction of the Co(II)-Cu(I1) protein causes minor, but significant, changes in the Co(I1) site as measured by magnetic circular dichroism.
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ورودعنوان ژورنال:
- The Journal of biological chemistry
دوره 248 11 شماره
صفحات -
تاریخ انتشار 1973