Autoxidation of oxymyoglobin. An overall stoichiometry including subsequent side reactions.

G. Tajima, K. Shikama

研究成果: Article

50 引用 (Scopus)

抜粋

Oxymyoglobin (MbO2) is oxidized easily to metmyoglobin (metMb) with generation of the superoxide anion, which can be converted by the spontaneous dismutation into H2O2, this being also a potent oxidant of MbO2. In the presence of sodium azide in stoichiometric amounts, however, the rate of autoxidation of MbO2 increased rapidly with increasing concentration of the anion, but soon reached a saturating level, the extent of which was about twice that of the normal autoxidation in buffer alone. Quantitative analysis has revealed that this enhancement is not due to the nucleophilic displacement of O2- from MbO2 by the anion (Satoh, Y., and Shikama, K. (1981) J. Biol. Chem. 256, 10272-10275), but is due to the additional oxidation of MbO2 by H2O2 freed from the metMb being occupied by the anion at the sixth coordination position. Based on these novel results and stoichiometric considerations, it is possible to propose a new view that H2O2 produced from O2- can be eliminated or decomposed mostly, if not completely, by the metMb resulting from the normal autoxidation reaction of MbO2, presumably via the formation of the ferryl species.

元の言語English
ページ(範囲)12603-12606
ページ数4
ジャーナルJournal of Biological Chemistry
262
発行部数26
出版物ステータスPublished - 1987 9 15
外部発表Yes

ASJC Scopus subject areas

  • Biochemistry
  • Molecular Biology
  • Cell Biology

フィンガープリント Autoxidation of oxymyoglobin. An overall stoichiometry including subsequent side reactions.' の研究トピックを掘り下げます。これらはともに一意のフィンガープリントを構成します。

  • これを引用