EFFECT OF Co$sup 60$ GAMMA RADIATION ON CATALASE (in Rumanian)
Catalase, isolated in crystalline form from equine, porcine, and avian liver and from equine erythrocytes was dissolved in 0.1M phosphate buffer at pH 7.4 and exposed to CO/sup 60/ gamma radiation at a dose rate of 5 mr/hr. Changes in the activity of the enzyme were studied polarographically after 30-min (2.5 mr) irradiation. Polarograms were obtained with a solution of hydrogen peroxide at 8.8 x 10/sup -4/M, and with the same solution after addition of native or irradiated peroxidase. The amplitude of the polarographic halfwave, particularly at lower voltages, was greater for the irradiated than for the native enzyme for liver, whereas it smaller in the case of the erythrocyte enzyme. These results indicate that the liver enzyme of three species was inactivated by gamma radiation, while red cell catalase was activated by the same treatment. Similar evidence of activation of red cell catalase was obtained when it was shaken with a 1: 1 mixture of chloroform and ethanol. The divergent behavior of liver and erythrocyte catalases toward irradiation is discussed in terms of the differences in the electronic structure of their prosthetic heme groups. (BBB)
- Research Organization:
- Facultatea de Medicina Veterinara, Bucharest
- NSA Number:
- NSA-17-037071
- OSTI ID:
- 4647687
- Journal Information:
- Acad. Rep. Populare Romine, Studii Cercetari Biochim., Journal Name: Acad. Rep. Populare Romine, Studii Cercetari Biochim. Vol. Vol: 5
- Country of Publication:
- Country unknown/Code not available
- Language:
- Rumanian
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