EC 2.1.1.44

Reaction: 3 S-adenosyl-L-methionine + L-histidine = 3 S-adenosyl-L-homocysteine + hercynine (overall reaction)
(1a) S-adenosyl-L-methionine + L-histidine = S-adenosyl-L-homocysteine + N^α-methyl-L-histidine
(1b) S-adenosyl-L-methionine + N^α-methyl-L-histidine = S-adenosyl-L-homocysteine + N^α,N^α-dimethyl-L-histidine
(1c) S-adenosyl-L-methionine + N^α,N^α-dimethyl-L-histidine = S-adenosyl-L-homocysteine + hercynine

For diagram of reaction click here.

Glossary: hercynine = N^α,N^α,N^α-trimethyl-L-histidine

Other name(s): dimethylhistidine N-methyltransferase; dimethylhistidine methyltransferase; histidine-α-N-methyltransferase; S-adenosyl-L-methionine:α-N,α-N-dimethyl-L-histidine α-N-methyltransferase; S-adenosyl-L-methionine:N^α,N^α-dimethyl-L-histidine N^α-methyltransferase

Systematic name: S-adenosyl-L-methionine:L-histidine N^α-methyltransferase (hercynine-forming)

Comments: Part of the biosynthetic pathway of ergothioneine.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 62213-53-0

References:

1. Ishikawa, Y. and Melville, D.B. The enzymatic α-N-methylation of histidine. J. Biol. Chem. 245 (1970) 5967-5973. [PMID: 5484456]

2. Seebeck, F.P. In vitro reconstitution of mycobacterial ergothioneine biosynthesis. J. Am. Chem. Soc. 132 (2010) 6632-6633. [PMID: 20420449]