Uroporphyrin-III C-methyltransferase (IPR006366)

Short name: CobA/CysG_C

Overlapping homologous superfamilies

Domain relationships


SUMT, an enzyme of the cobalamin and siroheme biosynthetic pathway, catalyzes the transformation of uroporphyrinogen III into precorrin-2. It transfers two methyl groups from S-adenosyl-L-methionine to the C-2 and C-7 atoms of uroporphyrinogen III to yield precorrin-2 via the intermediate formation of precorrin-1. SUMT is the first enzyme committed to the biosynthesis of siroheme or cobalamin (vitamin B12), and precorrin-2 is a common intermediate in the biosynthesis of corrinoids such as vitamin B12, siroheme and coenzyme F430 [PMID: 15522295, PMID: 15983414].

In some organisms, the SUMT domain is fused to the precorrin-2 oxidase/ferrochelatase domain to form siroheme synthase or to uroporphyrinogen-III synthase to form bifunctional uroporphyrinogen-III methylase/uroporphyrinogen-III synthase.

GO terms

Biological Process

GO:0019354 siroheme biosynthetic process

Molecular Function

GO:0008168 methyltransferase activity

Cellular Component

No terms assigned in this category.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.