Nitric oxide oxymyoglobin

Herod et al. [50] has studied the kinetics and mechanism of oxyhemoglobin (Hb02) and oxymyoglobin (Mb02) oxidation by nitric oxide. At pH 7.0 the rate constants for these reactions were equal to 43.6+0.5 x 1061 mol 1 s 1 for Mb02 and 89 + 3 x 106 1 mol-1 s-1 for Hb02. It has been suggested that these reactions proceed via the formation of intermediate peroxynitrito complexes, which were rapidly decomposed to the Met-form of proteins, for example ... 

The second reaction and certainly the major route for the destruction of nitric oxide in vivo is the fast and irreversible reaction with oxyhemoglobin (Hb) or oxymyoglobin to produce nitrate. 

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