Transferases;
Transferring one-carbon groups;
Methyltransferases
BRITE hierarchy

S-adenosyl-L-methionine:L-tryptophan 2-C-methyltransferase

S-adenosyl-L-methionine + L-tryptophan = S-adenosyl-L-homocysteine + L-2-methyltryptophan [RN:R08547]

R08547
Reaction

S-adenosyl-L-methionine [CPD:C00019];
L-tryptophan [CPD:C00078]

The enzyme, characterized from the bacterium Streptomyces laurentii, is involved in thiostrepton biosynthesis. It is a radical SAM enzyme that contains a [4Fe-4S] center and a cobalamin cofactor. The enzyme first transfers the methyl group from SAM to the bound cobalamin, followed by transfer from methylcobalamin to L-tryptophan, resulting in retention of the original methyl group configuration. The second transfer is likely to involve a CH3 radical species formed from methylcobalamin by the concerted action of a partially ligated radical SAM [4Fe-4S]2+/1+ center.

EC 2.1.1.106 created 1992

1  [PMID:2321967]

Frenzel T, Zhou P, Floss HG.

Formation of 2-methyltryptophan in the biosynthesis of thiostrepton: isolation of S-adenosylmethionine:tryptophan 2-methyltransferase.

Arch Biochem Biophys 278:35-40 (1990)
DOI:10.1016/0003-9861(90)90227-P

2  [PMID:23064318]

Pierre S, Guillot A, Benjdia A, Sandstrom C, Langella P, Berteau O

Thiostrepton tryptophan methyltransferase expands the chemistry of radical SAM enzymes.

Nat Chem Biol 8:957-9 (2012)
DOI:10.1038/nchembio.1091

[ag:ACN52303]

3  [PMID:26841310]

Blaszczyk AJ, Silakov A, Zhang B, Maiocco SJ, Lanz ND, Kelly WL, Elliott SJ, Krebs C, Booker SJ

Spectroscopic and Electrochemical Characterization of the Iron-Sulfur and Cobalamin Cofactors of TsrM, an Unusual Radical S-Adenosylmethionine Methylase.

J Am Chem Soc 138:3416-26 (2016)
DOI:10.1021/jacs.5b12592

4  [PMID:28747433]

Blaszczyk AJ, Wang B, Silakov A, Ho JV, Booker SJ

Efficient methylation of C2 in l-tryptophan by the cobalamin-dependent radical S-adenosylmethionine methylase TsrM requires an unmodified N1 amine.

J Biol Chem 292:15456-15467 (2017)
DOI:10.1074/jbc.M117.778548