Heat Inactivation of Superoxide Dismutase in Bovine Milk

Action of Bovine Superoxide Dismutase

On the Stability of Bovine Superoxide Dismutase

1. Apo-superoxide dismutase was more labile toward a variety of inactivating stresses than was the holoenzyme. 2. cu++ restored catalytic activity to the apoenzyme and markedly enhanced its thermal stability but Cu++ plus Zn++ were needed to attain the stability of the native enzyme. 3. Co’-+ or Hgii were able to replace Zn++ in increasing the thermal stability of the Cu+f-repleted apoenzyme. I...

Superoxide dismutase Superoxide dismutase

Elevation of superoxide dismutase in Halobacterium halobium by heat shock.

Exposure of Halobacterium halobium to 50 degrees C for 2.5 h in an aerobic environment resulted in a greater than twofold increase in the activity of the manganese-containing superoxide dismutase. Nondenaturing polyacrylamide gels stained for enzymatic activity did not reveal any additional isozymes of superoxide dismutase induced by the heat shock. The maximal effect was observed at 50 degrees...

Electron paramagnetic resonance studies of cobalt-copper bovine superoxide dismutase.

1. EPR spectra of cobalt-copper bovine superoxide dismutase at liquid nitrogen and liquid helium temperature show that the two metal centers are magnetically coupled. The temperature dependence of the spectra indicates that this coupling arises from an exchange interaction. 2. The EPR spectrum of the Co(I1) of the enzyme can only be seen after reduction of the Cu(II), at very low temperature. I...