Figure 1.

Catalytic cycle of αKG-dependent NHFe enzymes. αKG and substrate binding induces a 6-coordinate → 5-coordinate conversion (top), providing a site for O₂ to bind and form an Fe^IV—peroxo species that nucleophilically attacks αKG, producing a peroxo-bridged Fe^IV species (right).²⁴ Decarboxylation of αKG leads to the reactive Fe^IV=O intermediate (bottom right).