Cobalt-precorrin 5A hydrolase

Cobalt-precorrin 5A hydrolase (EC 3.7.1.12), CbiG (gene)) is an enzyme with systematic name cobalt-precorrin 5A acylhydrolase. This enzyme catalyses the following chemical reaction

cobalt-precorrin-5A + H₂O

\rightleftharpoons

cobalt-precorrin-5B + acetaldehyde + 2 H

This enzyme hydrolyses the ring A acetate delta-lactone of cobalt-precorrin-5A and releases a two-carbon fragment from the macrocyclic corrin ring as acetaldehyde. This is part of the biosynthetic pathway to cobalamin (vitamin B₁₂) in anaerobic bacteria such as Salmonella typhimurium and Bacillus megaterium.

References

Kajiwara Y, Santander PJ, Roessner CA, Pérez LM, Scott AI (August 2006). "Genetically engineered synthesis and structural characterization of cobalt-precorrin 5A and -5B, two new intermediates on the anaerobic pathway to vitamin B12: definition of the roles of the CbiF and CbiG enzymes". Journal of the American Chemical Society. 128 (30): 9971–8. doi:10.1021/ja062940a. PMID 16866557.

v t e Hydrolases: carbon-carbon (EC 3.7)
3.7.1	Fumarylacetoacetate hydrolase Kynureninase

v t e Enzymes
Activity	Active site Binding site Catalytic triad Oxyanion hole Enzyme promiscuity Diffusion-limited enzyme Cofactor Enzyme catalysis
Regulation	Allosteric regulation Cooperativity Enzyme inhibitor Enzyme activator
Classification	EC number Enzyme superfamily Enzyme family List of enzymes
Kinetics	Enzyme kinetics Eadie–Hofstee diagram Hanes–Woolf plot Lineweaver–Burk plot Michaelis–Menten kinetics
Types	EC1 Oxidoreductases (list) EC2 Transferases (list) EC3 Hydrolases (list) EC4 Lyases (list) EC5 Isomerases (list) EC6 Ligases (list) EC7 Translocases (list)