InterPro domain: IPR010723

This domain is found in the C-terminal region of oxygen-independent coproporphyrinogen-III oxidases (HemN) [ 1 ]. This enzyme catalyses the oxygen-independent conversion of coproporphyrinogen-III to protoporphyrinogen-IX [ 2 ], one of the last steps in haem biosynthesis. The function of this domain is unclear, but comparison to other proteins containing a radical SAM domain suggest it may be a substrate binding domain.

1. Crystal structure of coproporphyrinogen III oxidase reveals cofactor geometry of Radical SAM enzymes. EMBO J. 22, 6214-24
2. Terminal steps of haem biosynthesis. Biochem. Soc. Trans. 30, 590-5