Oxy-myoglobin

Figure 6-3 Schematic diagram of deoxy- and oxy-myoglobin near the active site.

Given these definitions, the steady state reaction diffusion equations for oxygen and oxy-myoglobin in the muscle fiber in radial coordinates are... 

These structures, which have been formulated by assuming that one of the unshared electron pairs on O2 forms the initial bond to the metal, are expected to lead to an angular geometry which has been observed in X-ray structures of model compounds, in oxy-myoglobin (Fig. 16-10), hi82 oxyhemoglobin. ... 

In fresh meat, in the presence of oxygen, the reversible reaction of myoglobin (Mb) with oxygen occurs and results in the formation of bright-red-colored oxy-myoglobin (Mb()2). In both pigments the iron is in ferrous form, and upon oxidation to ferric state, the brownish metmyoglobin (MMb) is formed. 

Chen H, Ikeda-Saito M, Shaik S (2008) Nature of the Fe-02 bonding in oxy-myoglobin effect of the Protein. J Am Chem Soc 130 14778-14790... 

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