INTERRELATION BETWEEN THE FUNCTION OF HEME-PROTEINS AND THE STRUCTURAL MODIFICATIONS OF THEIR PROTEIN PARTS
VIII. STUDIES ON THE REACTION OF METHEMOGLOBIN WITH FORMALDEHYDE
1956 年 43 巻 4 号 p. 509-522
詳細
1956 年 43 巻 4 号 p. 509-522
1. The combining affinity of methemoglobin for azide or fluoride decreased reversibly by the addition of formaldehyde.
2. The reaction of N3-methemoglobin with formaldehyde was found to proceed according to the following equation.
N3-metHb + 2HCHO_??_metHb(HCHO)2+N3-
F-metHb+2HCHO_??_metHb(HCHO)2+F-
3. The pK' values of methemoglobin-azide equilibrium in the presence of formaldehyde fall gradually as the pH increased, in the range of 5.0 to 7.0.
4. The absorption figure of acid methemoglobin was not altered by the addition of formaldehyde, but the absorption figure of alkali methemoglobin at pH 9.2 changed by the addition of formaldehyde.
5. It was assumed that two imdazole groups may combine with formaldehydes so as to cause a decrease in the binding affinity of methemoglobin with azide or fluoride.
The author wishes to thank Profs. K. Kaziro and G. Kikuchi for their continous guidance and encouragement during the course of this work.
