Alpha-ribazole phosphatase explained

adenosylcobalamin/α-ribazole phosphatase
Ec Number:	3.1.3.73
Cas Number:	251991-06-7
Go Code:	0043755

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

\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,,,,,,,,,,,,,,, and .

Notes and 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 . 26503–11 . 7929373 . 42 .
2. Warren MJ, Raux E, Schubert HL, Escalante-Semerena JC . 2002 . The biosynthesis of adenosylcobalamin (vitamin B₁₂) . Nat. Prod. Rep. . 19 . 390–412 . 12195810 . 10.1039/b108967f . 4 .
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 . 2210–8 . 17209023 . 10.1128/jb.01665-06. 6 . 1899380.