ON THE REACTION PROCESS OF PSEUDOHEMOGLOBIN FORMATION
1954 年 41 巻 2 号 p. 227-237
詳細
1954 年 41 巻 2 号 p. 227-237
The reaction process of pseudohemoglobin formation was studied quantitatively by means of spectrometrical observations.
1. The yields of pseudohemoglobin in the system of HbO2-KCN-H2O2 increased with increase of H2O2 or of KCN. Its maximum yield, however, never exceeded over a determinated limit.
2. Pseudohemoglobin was proved to be formed also in the reaction system of Hb-KCN-ascorbic acid-O2. Also in this system, the production of pseudohemoglobin reached to its maximum level relatively in short time and the reaction was then interrupted remaining large quantity of unaffected protoheme in the form of CN-metHb. In the presence of sufficient amount of KCN, the rate of pseudohemoglobin formation increased with increase of ascorbic acid added. But, the final yield of the pigment never exceeded over a certain limit. It was suggested thus, hemoglobin was converted in this reaction system into pseudohemoglobin and methemoglobin and in constant proportion of these two products.
3. With KCN of extremely lower concentrations, the final yield of pseudohemoglobin also decreased.
4. It seemed within the reaction process of pseudohemoglobin formation a slight denaturation has been occurred in the molecule of globin and the O2-binding capacity of hemoglobin was proved to be lowered within this reaction process.
5. For the reaction of pseudohemoglobin formation, pH values above 7.0 were afforded as favorable. It was suggested thus that CN-is effective in the present reaction, but not HCN.
The present investigation was supported by Prof. K. Kaziro, for which the authors wish to thank. The technical assistance of Dr. T. Tomimura in manometrical observations is also acknowledged with pleasure.
