Myoglobin hydrogen peroxide reaction

Hemoglobin and myoglobin in their ferric forms show rudimentary peroxidatic and catalatic activity, but ferrous peroxidase does not combine reversibly with molecular oxygen. Ionic iron also gives the hydrogen peroxide reactions but not the combination with oxygen. 

B. Reaction of Myoglobin with Hydrogen Peroxide Lipoxygenase Activity... 

Matsui T, Ozaki S, Liong E, Phillips GN, Watanabe Y (1999) Effects of the location of distal histidine in the reaction of myoglobin with hydrogen peroxide. J Biol Chem 274 2838-2844... 

Fig. 4.5. ESR spectrum of the ferryl myoglobin radical (Turner et al., 1990). ESR spectrum observed on reaction of (a) metmyoglobin (225 //M) and (b) oxymyoglobin with 250 / M hydrogen peroxide in the presence of 25 mM DMPO at pH 7.4 under normoxic...

In the editorial preface to the first volume of Advances in Catalysis the decision was made known not to publish reviews of specialized topics in biocatalysis but from time to time to bring reports in which the relationship and parallelism between this special field and normal catalysis are discussed. This is the first of these reports. Its purpose is to examine the reactions of four hemoproteins, hemoglobin, myoglobin, peroxidase, and catalase, which all contain the same coordination compound of iron—ferrous or ferric protoporphyrin attached to different protein molecules, with oxygen, hydrogen peroxide, and in a few cases additional reducing substances. Some of these reactions are specific ... 

It is possible to extend the free radical mechanism so that the derived rate equation has the required first order dependence by assuming that there is an auxiliary electron accepting group in hemoglobin and myoglobin that can act as cupric ions do in the ionic iron-hydrogen peroxide system catalyzing the reaction between Fe3+ and 02. ... 

In comparing the reactions of hemoglobin, myoglobin, peroxidase, and catalase with molecular oxygen or hydrogen peroxide in relation to the similar reactions of ionic iron the following conclusions can be drawn ... 

The stability of iron-peroxo complexes is marginal in heme systems in the presence of a strong proximal ligand (His, Cys, or Tyr), and the aqueous solution at a near-neutral pH. The numerous attempts to isolate such complexes obtained in reactions of hydrogen peroxide with P450 at ambient conditions have failed because of the inherent low stability and fast conversion to ferryl-oxo species with 0-0 bond scission There have been successful isolations of the ferriheme-peroxide complex in myoglobin, however . ... 

D.J. Lowe, C. Greenwood et al. (1997). Reaction of variant sperm-whale myoglobins with hydrogen peroxide The effects of mutating a histidine residue in the haem distal pocket. Biochem. J. 326, 109-115. 

Whether lipid oxidation in muscle foods is catalysed by the iron redox cycle or by formation of the ferryl ions is not clear. However, ferrous ions react with lipid hydroperoxides much faster than with hydrogen peroxide. As shown above, if the reaction of metmyoglobin with hydroperoxides produces ferryl radicals capable of initiating lipid oxidation, it is necessary to prevent the formation of metmyoglobin or methemoglobin. At acidic pH, ferric myoglobin can initiate lipid oxidation in the presence of lipid hydroperoxides. 

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