Alpha-ribazole phosphatase

adenosylcobalamin/α-ribazole phosphatase
Identifiers
EC no.	3.1.3.73
CAS no.	251991-06-7
Databases
IntEnz	IntEnz view
BRENDA	BRENDA entry
ExPASy	NiceZyme view
KEGG	KEGG entry
MetaCyc	metabolic pathway
PRIAM	profile
PDB structures	RCSB PDB PDBe PDBsum
Gene Ontology	AmiGO / QuickGO
Search PMC articles PubMed articles NCBI proteins

The primary biochemical reaction catalyzed by the enzyme adenosylcobalamin/α-ribazole phosphatase (formerly α-ribazole phosphatase)[1] (EC 3.1.3.73) is

adenosylcobalamin 5′-phosphate + H₂O = coenzyme B₁₂ + phosphate

This enzyme can also catalyze the following reaction in vitro, however it is not the biologically relevant reaction

α-ribazole 5′-phosphate + H₂O ${\displaystyle \rightleftharpoons }$ α-ribazole + phosphate

This enzyme belongs to the family of hydrolases, specifically those acting on phosphoric monoester bonds. The systematic name is adenosylcobalamin/α-ribazole-5′-phosphate phosphohydrolase. This enzyme is also called CobC. It is part of the biosynthetic pathway to cobalamin (vitamin B₁₂) in bacteria.[2][3]

See also

• Cobalamin biosynthesis

Structural studies

As of late 2007, 16 structures have been solved for this class of enzymes, with PDB accession codes 2ENU, 2ENW, 2EOA, 2OWE, 2P2Y, 2P2Z, 2P30, 2P6M, 2P6O, 2P75, 2P77, 2P78, 2P79, 2P9Y, 2P9Z, and 2PA0.

References

1. O'Toole GA, Trzebiatowski JR, Escalante-Semerena JC (1994). "The cobC gene of Salmonella typhimurium codes for a novel phosphatase involved in the assembly of the nucleotide loop of cobalamin". J. Biol. Chem. 269 (42): 26503–11. doi:10.1016/S0021-9258(18)47223-7. PMID 7929373.
2. Warren MJ, Raux E, Schubert HL, Escalante-Semerena JC (2002). "The biosynthesis of adenosylcobalamin (vitamin B₁₂)". Nat. Prod. Rep. 19 (4): 390–412. doi:10.1039/b108967f. PMID 12195810.
3. Zayas CL, Escalante-Semerena JC (2007). "Reassessment of the late steps of coenzyme B₁₂ synthesis in Salmonella enterica: evidence that dephosphorylation of adenosylcobalamin-5′-phosphate by the CobC phosphatase is the last step of the pathway". J. Bacteriol. 189 (6): 2210–8. doi:10.1128/jb.01665-06. PMC 1899380. PMID 17209023.