Metalloporphyrins-dioxygen moiety

By determining the rate constants for the various steps in Scheme 8, it has been demonstrated [78] that electron or proton transfer to the metalloporphyrin-dioxygen moiety weakens the 0-0 bond, thereby... 

Heme proteins are one of the largest classes of metalloproteins studied to date see Iron Heme Proteins Dioxygen Transport Storage Iron Heme Proteins, Peroxidases, Catalases <6 Catalase-peroxidases). More than 5% of protein structures in the Protein Data Bank contain at least one heme moiety. It is no wonder that designing heme proteins has been one of the most active areas of research. Since the dominant secondary structure in heme proteins is a-hehces (accounting for 77% of all secondary structures in known heme proteins),a number of Q -helix-containing metalloporphyrin-peptides have been synthesized using either covalent or noncovalent approaches. 

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