The bioinorganic chemistry of iron in oxygenases and supramolecular assemblies

Abstract

The bioinorganic chemistry of iron is central to life processes. Organisms must recruit iron from their environment, control iron storage and trafficking within cells, assemble the complex, iron-containing redox cofactors of metalloproteins, and manage a myriad of biochemical transformations by those enzymes. The coordination chemistry and the variable oxidation states of iron provide the essential mechanistic machinery of this metabolism. Our current understanding of several aspects of the chemistry of iron in biology are discussed with an emphasis on the oxygen activation and transfer reactions mediated by heme and nonheme iron proteins and the interactions of amphiphilic iron siderophores with lipid membranes.

Cytochrome P450-type Hydroxylation and Epoxidation in a Tyrosine-liganded Hemoprotein, Catalase-related Allene Oxide Synthase

“…This apparent limitation should be further explored in direct comparison with P450 epoxygenases and hydroxylases that normally react within the arachidonate double bonds or with CYP5, CYP8A, or CYP74 enzymes charged with iodosylbenzene. Alkane hydroxylation is considered the tour-de-force reaction of the thiolate-liganded heme monooxygenases (33). Nonetheless, one might question whether all cytochrome P450s have the innate ability to hydroxylate plain alkanes.…”

Mechanisms of cytochrome P450 substrate oxidation: MiniReview

“…Much of the evidence for the perferryl oxygen complex (FeO 3+ ) comes from biomimetic experiments [10] and comparisons with peroxidase chemistry. Some spectral evidence has been presented for the FeO 3+ species, probably best represented as a Fe IV = O/porphyrin radical species [11], although this is an unstable entity and has been estimated to have a t 1/2 of 200 ms at 20…”

Spectroscopic observation of iodosylarene metalloporphyrin adducts and manganese(V)-oxo porphyrin species in a cytochrome P450 analogue

“…However, along with the accumulation of various evidence, multiple oxidizing species (Fig. 1a) were speculated to be able to transfer oxygen atoms to the substrates [20][21][22] and the mechanisms were found to be more complicated than those initially proposed 23,24 . For example, ferric-peroxo species were proven to react with electrophiles 25 .…”