Copper zinc superoxide dismutase calculations

The simplest direct assay was described by Marklund (1976). Superoxide was generated from its potassium salt at alkaline pH where its stability increases. The decay at 250 nm in the presence and absence of superoxide dismutase is measured in a standard spectrophotometer. The assay is carried out in such a way that the rate of a decay in the presence of the enzyme is within the time response of the apparatus (Fig. 1). One unit of activity is arbitrarily taken as the enzyme activity that results in the dismutation of O2 at a rate of 0. lsec . This rate of dismutation corresponds to 5.5 ng bovine copper/zinc superoxide dismutase and to 64.5 ng bovine manganese superoxide dismutase under the conditions described by Marklund (1976). The rate constants calculated for both enzymes were... 

A relatively large number of theoretical studies on the complete calculation of redox potentials of transition metal active sites in metalloproteins have been published. Metalloproteins studied include manganese superoxide dismutase, iron superoxide dismutase, copper-zinc superoxide dismutase, iron-sulfur proteins, cytochrome f, components of the photosynthetic reaction center, and peroxidases. ... 

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