Uroporphyrinogen-III C-methyltransferase

Uroporphyrinogen-III C-methyltransferase
Identifiers
EC no.	2.1.1.107
CAS no.	125752-76-3
Databases
IntEnz	IntEnz view
BRENDA	BRENDA entry
ExPASy	NiceZyme view
KEGG	KEGG entry
MetaCyc	metabolic pathway
PRIAM	profile
PDB structures	RCSB PDB PDBe PDBsum
Search PMC articles PubMed articles NCBI proteins

Uroporphyrinogen-III C-methyltransferase (EC 2.1.1.107), uroporphyrinogen methyltransferase, uroporphyrinogen-III methyltransferase, adenosylmethionine-uroporphyrinogen III methyltransferase, S-adenosyl-L-methionine-dependent uroporphyrinogen III methylase, uroporphyrinogen-III methylase, SirA, CysG, CobA, uroporphyrin-III C-methyltransferase, S-adenosyl-L-methionine:uroporphyrin-III C-methyltransferase) is an enzyme with systematic name S-adenosyl-L-methionine:uroporphyrinogen-III C-methyltransferase. ^{[1] [2] [3]} This enzyme catalyses the following chemical reaction

2 S-adenosyl-L-methionine + uroporphyrinogen III ${\displaystyle \rightleftharpoons }$ 2 S-adenosyl-L-homocysteine + precorrin-2 (overall reaction)

(1a) S-adenosyl-L-methionine + uroporphyrinogen III ${\displaystyle \rightleftharpoons }$ S-adenosyl-L-homocysteine + precorrin-1

(1b) S-adenosyl-L-methionine + precorrin-1 ${\displaystyle \rightleftharpoons }$ S-adenosyl-L-homocysteine + precorrin-2

uroporphyrinogen III substrate of the enzyme

precorrin-2 product of the enzyme

Uroporphyrinogen-III C-methyltransferase catalyses two methylation reactions. The first reaction converts uroporphyrinogen III into precorrin-1. The second converts precorrin-1 into precorrin-2. These reactions are part of the biosynthetic pathway to cobalamin (vitamin B₁₂) in both anaerobic and aerobic bacteria.

See also

• Cobalamin biosynthesis

References

1. Warren MJ, Gonzalez MD, Williams HJ, Stolowich NJ, Scott AI (1990). "Uroporphyrinogen-III methylase catalyzes the enzymatic-synthesis of sirohydrochlorin-II and sirohydrochlorin-IV by a clockwise mechanism". J. Am. Chem. Soc. 112: 5343–5345. doi:10.1021/ja00169a048.
2. Warren MJ, Roessner CA, Santander PJ, Scott AI (February 1990). "The Escherichia coli cysG gene encodes S-adenosylmethionine-dependent uroporphyrinogen III methylase". The Biochemical Journal. 265 (3): 725–9. doi:10.1042/bj2650725. PMC   1133693 . PMID   2407234.
3. Schubert HL, Raux E, Brindley AA, Leech HK, Wilson KS, Hill CP, Warren MJ (May 2002). "The structure of Saccharomyces cerevisiae Met8p, a bifunctional dehydrogenase and ferrochelatase". The EMBO Journal. 21 (9): 2068–75. doi:10.1093/emboj/21.9.2068. PMC   125995 . PMID   11980703.

External links

• Uroporphyrinogen-III+C-methyltransferase at the U.S. National Library of Medicine Medical Subject Headings (MeSH)