摘要
应用脱氧核糖降解法研究了离体条件下Cu，Zn-SOD与H2O2反应产生·OH，并对其机理进行了探讨。H2O2可使Cu，Zn-SOD失活，在失活过程中有·OH产生，甲酸钠和苯甲酸钠均能不同程度地保护Cu，Zn-SOD和降低H2O2与Cu，Zn-SOD反应中·OH的产额；热失活SOD也可和H2O2反应生成·OH，且效能高于活性Cu，Zn-SOD；用螫合剂脱去Cu，Zn-SOD的金属辅基后，脱辅基的SOD蛋白不能和H2O2反应产生·OH；Cu2＋和H2O2反应产生·OH的效率很高，而Zn2＋产生·OH的效率很低。实验结果提示Cu，Zn－SOD与H2O2反应产生的·OH可能是SOD活性中心的Cu2＋与H2O2发生Fenton反应的结果．
The generation of .OH from Cu,Znroontaining superoxide dismutase (CuZn-SOD) reacting with H,O, was studied by using deoxyribose degradation method in which deoxyribose reacts with. OH to release TBA-reactive compounds. Cu, ZnSOD could be inactivated by H,O2, during which. OH was produced. Formate and benzoate,scavengers of. OH, could partially protect Cu,Zn-SOD against inaCtivation by H2O2, and could inhibit the generation of. OH from Cu, Zn-SOD reacting with H2O2. Heat inactivated Cu,Zn-SOD could also react with HZOZ to generate. OH, and it was more effective in generating .OH than the active Cu,Zn-SOD. Apoprotein of Cu,ZnSOD did not catalyze .OH generation from HZO2. Zn2+ could hardly react with H2O2 to form 'OH, whereas Cu2+ was highly effective in generating. OH through Fenton reaction. These observations suggest that the generation of. OH from Cu,Zn-SOD reacting with Hood is due to the Fenton reaction between HZO, and Cu2+ in the active center of Cu,Zn-SOD.
出处
《热带亚热带植物学报》
CAS
CSCD
1998年第2期111-116,共6页
Journal of Tropical and Subtropical Botany
基金
国家自然科学基金
广东省自然科学基金
关键词
过氧化氢
羟自由基
脱氧核糖降解法
CU
ZN-SOD
Copper-zinc superoxide dismutase, Hydrogen peroxide, Hydroxyl radical,Copper ion, Deoxyribose degradation method
