In enzymology, a precorrin-4 C11-methyltransferase (EC 2.1.1.133) is an enzyme that catalyzes the chemical reaction

S-adenosyl-L-methionine + precorrin-4 ${\displaystyle \rightleftharpoons }$ S-adenosyl-L-homocysteine + precorrin-5

The two substrates of this enzyme are S-adenosyl methionine and precorrin 4; its two products are S-adenosylhomocysteine and precorrin 5.

This enzyme belongs to the family of transferases, specifically those transferring one-carbon group methyltransferases. The systematic name of this enzyme class is S-adenosyl-L-methionine:precorrin-4 C11 methyltransferase. Other names in common use include precorrin-3 methylase, and CobM. It is part of the biosynthetic pathway to cobalamin (vitamin B₁₂) in aerobic bacteria.

See also

• Cobalamin biosynthesis

Structural studies

As of late 2007, two structures have been solved for this class of enzymes, with PDB accession codes 1CBF and 2CBF.

References

• Thibaut D, Debussche L (1990). "Genetic and sequence analysis of an 8.7-kilobase Pseudomonas denitrificans fragment carrying eight genes involved in transformation of precorrin-2 to cobyrinic acid". J. Bacteriol. 172 (10): 5980–90. doi:10.1128/jb.172.10.5980-5990.1990. PMC 526920. PMID 2211521.
• Roth JR, Lawrence JG, Rubenfield M, Kieffer-Higgins S, Church GM (1993). "Characterization of the cobalamin (vitamin B12) biosynthetic genes of Salmonella typhimurium". J. Bacteriol. 175 (11): 3303–16. doi:10.1128/jb.175.11.3303-3316.1993. PMC 204727. PMID 8501034.