INTERRELATION BETWEEN THE FUNCTION OF HEMEPROTEINS AND THE STRUCTURAL MODIFICATIONS OF THEIR PROTEIN PARTS

Abstract

Catalytic and peroxidatic activities of purified equine liver catalase were determined manometrically (O2 evolution) and spectrophotometrically (purpurogallin determination), respectively. When pyrogallol (H2A) was present in a mol. ratio of H2A/H2O2 =1/1000, the peroxidatic reaction began to appear; at a ratio of more than approximately 1, the peroxidatic reaction was predominant. The addition of salicylate or benzoate (1-2[image]) caused the shift of Soret band of catalase solution and reduced the catalytic acitivity, with the increasing salicylate or benzoate concentration. When an appreciable peroxidatic reaction occurred by the addition of H2A (H2A/H2O2 =1/1000 - 1/5), the addition of salicylate or benzoate suppressed the peroxidatic activity and restored the catalytic one; but this was not the case with the reaction system, in which the peroxidatic reaction was advantageous by higher concentration of H2A (H2A/H2O2> 1), while the peroxidatic activity was inhibited by benzoate or salicylate at a concentration of H2A/H2O=1/5, and rather promoted when H2A/H2O2>=3.