Ferric peroxo anion

Sivaramakrishnan S, Ouellet H, Matsumura H, Guan S, Moenne-Loccoz P, Burlingame AL, Ortiz de Montellano PR (2012) Proximal ligand electron donation and reactivity of the cytochrome P450 ferric-peroxo anion. J Chem Soc 134 6673-6684... 

The reaction sequence at the heme active site starts with the binding of unactivated triplet dioxygen forming the so-called oxy-heme complexes. The iron center in 02-activating heme enz5maes is then thought to be converted into a peroxo anion species. It can be protonated to form a ferric hydroperoxo intermediate usually termed compormd 0 (183), which is a crucial reactive species in catalase and peroxidase enz5nne catalysis (Fig. 21). These hydroperoxo intermediates of hemoproteins are important... 

Protonation of the distal oxygen of this peroxo anion to generate the Fe- -OOH , ferric-hydroperoxo complex. 

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