Heme oxygenase hydroperoxo complex

Hydroperoxo-ferric complex in heme oxygenase reserves a special place among other heme enzymes being the main catalytically active intermediate on the first monooxygenation step of HO catalysis. Conversion of heme to biliverdin, catalyzed by HO, begins with reduction of the ferric heme iron, binding of dioxygen, and second reduction... 

Despite detailed and repeated measurements by various techniques, almost no evidence can be found for the formation of (LFe=0) in the cyclidene systems, despite the fact that peroxo complexes form readily and by one route that constitutes the reverse of the reaction of equation 6. The results reported here also stand in contrast to recent studies based on non-heme oxygenase model systems that indicate the possibility of multiple pathways, implying that (hydroperoxo)iron(III) species might have catalytic activity e.g., a) Y.-D. Wu, K. N. Houk, J. S. Valentine, and W. Nam, Inorg, Chem, 31 718 (1992) b) W. Nam, R. Ho, and J. S. Valentine, J, Am,... 

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