Cobalamin adenosyltransferase-like (IPR016030)

Short name: CblAdoTrfase-like

Overlapping homologous superfamilies

Domain relationships



ATP:cob(I)alamin (or ATP:corrinoid) adenosyltransferases (EC:, catalyse the conversion of cobalamin (vitamin B12) into its coenzyme form, adenosylcobalamin (AdoCbl)or coenzyme B12 [PMID: 15516577]. AdoCbl contains an adenosyl moiety liganded to the cobalt ion of cobalamin via a covalent Co-C bond. AdoCbl is required as a cofactor for the activity of certain enzymes.

ATP:cob(I)alamin adenosyltransferases are classed into three groups: CobA-type [PMID: 16672609], EutT-type [PMID: 15317775] and PduO-type [PMID: 11160088]. Each of the three enzyme types appears to be specialised for particular AdoCbl-dependent enzymes or for the de novo synthesis AdoCbl. PduO and EutT are distantly related, sharing short conserved motifs, while CobA is evolutionarily unrelated and is an example of convergent evolution.

This entry represents a structural domain consisting of 4-helical bundle with a left-handed twist and one cross-over loop that goes across to a different side of the 4-helical bundle; there is no internal metal-binding site. This domain is found in EutT- and PduO-type ATP:cob(I)alamin adenosyltransferases. PduO functions to convert cobalamin to AdoCbl for 1,2-propanediol degradation [PMID: 9311132], while EutT produces AdoCbl for ethanolamine utilisation [PMID: 16636051]. This domain is also found in the hypothetical protein Ta1238 from the archaeon Thermoplasma acidophilum [PMID: 15704011].

Contributing signatures

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