MULTIPLE ACTIONS OF SUPEROXIDE-DISMUTASE - WHY CAN IT BOTH INHIBIT AND STIMULATE REDUCTION OF OXYGEN BY HYDROQUINONES

被引:38
作者
BANDY, B [1 ]
MOON, J [1 ]
DAVISON, AJ [1 ]
机构
[1] SIMON FRASER UNIV,SCH KINESIOL,FAC APPL SCI,BIOENERGET RES LAB,BURNABY V5A 1S6,BC,CANADA
关键词
Chain propagation; Free radicals; Hydroquinone autoxidation; Inner sphere electron transfers; Metal coordination; Oxygen reduction; Semiquinone; Superoxide dismutase;
D O I
10.1016/0891-5849(90)90117-2
中图分类号
Q5 [生物化学]; Q7 [分子生物学];
学科分类号
071010 ; 081704 ;
摘要
Superoxide dismutase can either inhibit or stimulate autoxidation hydroquinones, suggesting multiple roles for O2·-. Inhibitory actions of superoxide dismutase include termination of O2·--propagated reaction chains and metal chelation by the apoprotein. Together, chelation of metals and termination of O2·--propagated chains can effectively prevent reduction of oxygen. Chain termination by superoxide dismutase can thus account for negligible accumulation of H2O2 without invoking a superoxide: semiquinone oxidoreductase activity for this enzyme. One stimulatory action of superoxide dismutase is to decrease thermodynamic limitations to reduction of oxygen. Whether superoxide dismutase inhibits or accelerates an autoxidation depends on the reduction potentials of the quinone and the availability of metal coordination for inner sphere electron transfers. © 1990.
引用
收藏
页码:143 / 148
页数:6
相关论文
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  • [1] Cadenas, Mira, Brumark, Lind, Segura-Aguilar, Ernster, Effect of superoxide dismutase on the autoxidation of various hydroquinones—a possible role of superoxide dismutase as a superoxide: semiquinone oxidoreductase, Free Radical Biol. Med., 5, pp. 71-79, (1988)
  • [2] Ollinger, Buffington, Ernster, Cadenas, Effect of superoxide dismutase on the autoxidation of substituted hydro- and semi-naphthoquinones, Chem. Biol. Interact., 73, pp. 53-76, (1990)
  • [3] Winterbourn, Inhibition of the autoxidation of divicine and isouramil by the combination of superoxide dismutase and reduced glutathione, Arch. Biochem. Biophys., 271, pp. 447-455, (1989)
  • [4] Ishii, Fridovich, Dual effects of superoxide dismutase on the autoxidation of 1,4-naphthohydroquinone, Free Radical Biol. Med., 8, pp. 21-24, (1990)
  • [5] Misra, Fridovich, The role of superoxide anion in the autoxidation of epinephrine and a simple assay for superoxide dismutase, J. Biol. Chem., 247, pp. 3170-3175, (1972)
  • [6] Bandy, Davidson, Interactions between metals, ligands and oxygen in the autoxidation of 6-hydroxydopamine: mechanisms by which metal chelation enhances inhibition by superoxide dismutase, Arch. Biochem. Biophys., 259, pp. 305-315, (1987)
  • [7] Lovstad, Copper catalyzed oxidation of ascorbate (vitamin C). Inhibitory effect of catalase, superoxide dismutase, serum proteins (ceruloplasmin, albumin, apotransferrin) and amino acids, Int. J. Biochem., 19, pp. 309-313, (1987)
  • [8] Gee, Davidson, Intermediates in the aerobic autoxidation of 6-hydroxydopamine: relative importance under different reaction conditions, Free Radical Biol. Med., 6, pp. 271-284, (1989)
  • [9] Gee, Davison, 6-Hydroxydopamine does not reduce oxygen directly but requires a co-reductant, Arch. Biochem. Biophys., 231, pp. 164-168, (1984)
  • [10] Mukherjee, One-electron reduction of juglone (5-hydroxy,4-naphthoquinone): a pulse radiolysis study, Radiat. Phys. Chem., 29, pp. 455-462, (1987)