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CATH Superfamily 1.20.1200.10

Cobalamin adenosyltransferase-like

The name of this superfamily has been modified since the most recent official CATH+ release (v4_4_0). At the point of the last release, this superfamily was named:

"
Cobalamin adenosyltransferase-like
".

Functional Families

Overview of the Structural Clusters (SC) and Functional Families within this CATH Superfamily. Clusters with a representative structure are represented by a filled circle.
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FunFam 3: ATP:cob(I)alamin adenosyltransferase

There are 1 EC terms in this cluster

Please note: EC annotations are assigned to the full protein sequence rather than individual protein domains. Since a given protein can contain multiple domains, it is possible that some of the annotations below come from additional domains that occur in the same protein, but have been classified elsewhere in CATH.

Note: The search results have been sorted with the annotations that are found most frequently at the top of the list. The results can be filtered by typing text into the search box at the top of the table.

EC Term Annotations Evidence
Corrinoid adenosyltransferase. [EC: 2.5.1.17]
(1) 2 ATP + 2 cob(II)alamin + a reduced flavoprotein = 2 triphosphate + 2 adenosylcob(III)alamin + an oxidized flavoprotein. (2) 2 ATP + 2 cob(II)yrinic acid a,c-diamide + a reduced flavoprotein = 2 triphosphate + 2 adenosylcob(III)yrinic acid a,c-diamide + an oxidized flavoprotein.
  • The corrinoid adenosylation pathway comprises three steps: (i) reduction of Co(III) to Co(II) by a one-electron transfer.
  • This can occur non-enzymically in the presence of dihydroflavin nucleotides or reduced flavoproteins.
  • (ii) Co(II) is bound by corrinoid adenosyltransferase, resulting in displacement of the lower axial ligand by an aromatic residue.
  • The reduction potential of the 4-coordinate Co(II) intermediate is raised by ~250 mV compared with the free compound, bringing it to within physiological range.
  • This is followed by a second single-electron transfer from either free dihydroflavins or the reduced flavin cofactor of flavoproteins, resulting in reduction to Co(I).
  • (iii) the Co(I) conducts a nucleophilic attack on the adenosyl moiety of ATP, resulting in transfer of the deoxyadenosyl group and oxidation of the cobalt atom to Co(III) state.
  • Three types of corrinoid adenosyltransferases, not related by sequence, have been described.
  • In the anaerobic bacterium Salmonella enterica they are encoded by the cobA gene (a housekeeping enzyme involved in both adenosylcobalamin de novo biosynthesis and salvage), the pduO gene (involved in (S)-propane-1,2-diol utilization), and the eutT gene (involved in ethanolamine utilization).
  • Since EutT hydrolyzes triphosphate during catalysis, it is classified as a separate enzyme.
  • The mammalian enzyme belongs to the PduO type.
  • The enzyme can act on other corrinoids, such as cob(II)inamide.
 156 A0A045JVI3 A0A045JVI3 A0A045JVI3 A0A045JVI3 A0A045JVI3 A0A045JVI3 A0A045JVI3 A0A045JVI3 A0A045JVI3 A0A045JVI3
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