Myoglobin oxygen complexes

Synthetic models of myoglobin and hemoglobin are complex molecules that mimic the stereochemical properties of the protein active center [24] and have oxygen affinities similar to those measured for the protein [25-27]. The first heme model that reversibly binds oxygen (i.e. the picket-fence-oxygen complex Fe(TpivPP)(l,2-Melm)(02), shown in Fig. 3.3) was obtained in the early nine-teen-seventies by Collman and coworkers (TpivPP = tetrapivalami-nophenyl porphyrin 2-meIm = 2-methylimidazole) [18]. Research on synthetic models of the protein has led to a deeper understand-... 

The polymer shares the following properties with hemoglobin and myoglobin (a) good solubility in water in order to achieve high concentration of O2 (b) hindrance of irreversible oxidation of the oxygen complex by the functionalized polymer and (c) imitation of a distal imidazole. 

Ribbon views of proteins with varying amounts of helices and pleated sheets. Immunoglobulin, an antibody, is made up almost entirely of pleated sheets (magenta). Myoglobin, which stores oxygen in muscle tissue, is composed of about 70% helix (blue). G-Actin, a component of muscle protein fibers, is a complex mixture of helices and pleated sheets. Regions with no specific secondaiy stmcture are shown in orange. 

The interaction of Fe(II) with small molecules has received much attention. The Fe(II)/ oxygen system must be one of the most studied chemical interactions. Since the Fe-porphyrin complex forms the core of the naturally occurring iron respiratory proteins myoglobin and... 

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