Superoxide dismutase enzymes, 310

Marklund, S.L., Bjelle, A. and Elmqvist, L. (1986). Superoxide dismutase enzymes of the synovial fluid in rheumatoid arthritis and in reactive arthritides. Ann. Rheum. Dis. 45, 847-851. 

J.M. McCord and I. Fridovich, Superoxide dismutase. Enzymic function for erythrocuprein (hemo-cuprein). J. Biol. Chem. 244, 6049-6055 (1969). 

Superoxide dismutase enzymes are functional dimers of molecular weight (Mr) of approximately 32 kDa. The enzymes contain one copper ion and one zinc ion per subunit. Superoxide dismutase (SOD) metalloenzymes function to disproportionate the biologically harmful superoxide ion-radical according to the following reaction ... 

Section 5.2.3 in Chapter 5. Superoxide dismutase enzymes catalyze dismutation of the superoxide anion radical (O2 ) according to the summary reactions in equation 7.1 ... 

Riley DP (1999) Functional mimics of superoxide dismutase enzymes as therapeutic agents. Chem. Rev. 99 2573-2587. 

The biosensor [1] was obtained by coupling a transducer (an ampero-metric electrode for hydrogen peroxide) with the superoxide dismutase enzyme immobilized in kappa-carrageenan gel. Sandwich the gel containing the enzyme between a cellulose acetate membrane and a dialysis membrane. Secure the whole assembly to the electrode with an O-ring (Fig. 12.1). 

Delivery of Copper to the Cytosol The Copper Requiring Superoxide Dismutase Enzyme... 

The efficiency of the simple Na+ salts to inhibit the reactivity of 02 is very spectacular, and it matches the reactivity of superoxide dismutase enzymes in biological systems [173]. It is thus a unique property of the electron-reservoir complexes which lets us investigate the electron-transfer to O2 in various media. The follow-up reactions of superoxide radical anion are reminiscent of its damage for cells in the aging processes which is well-known but little understood [173]. 

Solutions of dicyclohexyl-18 crown 6 in DMSO have been used to prepare pale yellow 0.15 mol P solutions of KO2 which contain the O2 anion in approximately the same concentration. The specificity of the superoxide dismutase enzyme was used to show that the solution did indeed contain the superoxide ion in solution. I hc redox potentials of the superoxide and hydroperoxy free radicals, O2 and HO2, have been measured by the fast reaction technique of pulse radiolysis and kinetic absorption spectrophotometry. A d.t.a. study has shown that, during the heating of LiC104-K02 mixtures containing <30% KO2, a eutectic melt occurred at 100—250 C with the loss of superoxide oxygen. At 250—300 °C the mixture melted with loss of peroxide oxygen and at 360— 500 °C the perchlorate decomposed with the loss of all the perchlorate oxygen. 

Paynter DI. 1980. Changes in activity of the manganese superoxide dismutase enzyme in tissues of the rat with changes in dietary manganese. J Nutr 110 437-447. 

Valentine and Curtis have reported a preliminary study of the reaction of KO2 with a Cu(II) complex, which results in formation of a Cu(I) complex and liberation of molecular oxygen. This reaction is of interest in connection with superoxide dismutase enzymes, which contain transition metals. 

Advantages of Superoxide Dismutase Mimics over Superoxide Dismutase Enzymes... 

SP 131 describes Pauling s 1933 discovery and verification of the superoxide free radical, which now, 67 years later—has become of much interest as an active agent in oxidative damage to tissues and in the aging process. The control of this substance in living organisms, by means of the superoxide dismutase enzyme that catalyzes its decomposition, is an example of a potential task of orthomolecular medicine (see below). 

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