Cobalt-precorrin-7 (C15)-methyltransferase (decarboxylating) explained

Cobalt-precorrin-7 (C15)-methyltransferase (decarboxylating)
Ec Number:	2.1.1.196

Cobalt-precorrin-7 (C₁₅)-methyltransferase (decarboxylating) (CbiT) is an enzyme with systematic name S-adenosyl-L-methionine:precorrin-7 C₁₅-methyltransferase (C₁₂-decarboxylating).^{[1] [2]} This enzyme catalyses the following chemical reaction

\rightleftharpoons cobalt-precorrin-8x + S-adenosyl-L-homocysteine + CO₂

This enzyme catalyses both methylation at C-15 and decarboxylation of the C-12 acetate side chain of cobalt-precorrin-7 in the anaerobic pathway^[3] of adenosylcobalamin biosynthesis in bacteria such as Salmonella typhimurium, Bacillus megaterium, and Propionibacterium freudenreichii subsp. shermanii.

See also

• Cobalamin biosynthesis

Notes and References

1. Keller JP, Smith PM, Benach J, Christendat D, deTitta GT, Hunt JF . The crystal structure of MT0146/CbiT suggests that the putative precorrin-8w decarboxylase is a methyltransferase . Structure . 10 . 11 . 1475–87 . November 2002 . 12429089 . 10.1016/S0969-2126(02)00876-6 . free .
2. Santander PJ, Kajiwara Y, Williams HJ, Scott AI . Structural characterization of novel cobalt corrinoids synthesized by enzymes of the vitamin B12 anaerobic pathway . Bioorganic & Medicinal Chemistry . 14 . 3 . 724–31 . February 2006 . 16198574 . 10.1016/j.bmc.2005.08.062 .
3. Web site: Pathway: adenosylcobalamin biosynthesis I (anaerobic) . R. Caspi . MetaCyc Metabolic Pathway Database . 2013-09-25 . 2020-04-24 .