超氧化物歧化酶 来源于辣根

Superoxide dismutases are a group of low molecular weight metalloproteins present in all aerobic cells of plants, animals and micro-organisms. They provide protection against damaging reactions with the superoxide radical anion (O2-) by catalyzing its disproportionation into oxygen and hydrogen peroxide.

Superoxide dismutase from horseradish has been used in a study to assess the correlation between CuZn superoxide dismutase and glutathione reductase, and environmental and xenobiotic stress tolerance in maize inbreds. Superoxide dismutase from horseradish has also been used in a study to investigate chemiluminometric enzyme sensors for flow-injection analysis.

Catalyzes the dismutation of superoxide radicals to hydrogen peroxide and molecular oxygen. Plays a critical role in the defense of cells against the toxic effects of oxygen radicals. Competes with nitric oxide (NO) for superoxide anion (which reacts with NO to form peroxynitrite), thereby SOD promotes the activity of NO. SOD has also been shown to suppress apoptosis in cultured rat ovarian follicles, neural cell lines, and transgenic mice.

One unit will inhibit reduction of cytochrome c by 50% in a coupled system with xanthine oxidase at pH 7.8 at 25 °C in a 3.0 mL reaction volume. Xanthine oxidase concentration should produce an initial ΔA₅₅₀ of 0.025 ± 0.005 per min.

含磷酸钾缓冲盐的冻干粉

关于试验方法请参阅 McCord, J.M. and Fridovich,I., J. Biol. Chem., 244, 6049 (1969)。