sarcosine/dimethylglycine N-methyltransferase;
ApDMT;
sarcosine-dimethylglycine methyltransferase;
SDMT;
sarcosine dimethylglycine N-methyltransferase;
S-adenosyl-L-methionine:N,N-dimethylglycine N-methyltransferase

Transferases;
Transferring one-carbon groups;
Methyltransferases

S-adenosyl-L-methionine:sarcosine(or N,N-dimethylglycine) N-methyltransferase [N,N-dimethylglycine(or betaine)-forming]

2 S-adenosyl-L-methionine + sarcosine = 2 S-adenosyl-L-homocysteine + betaine (overall reaction) [RN:R10061];
(1a) S-adenosyl-L-methionine + sarcosine = S-adenosyl-L-homocysteine + N,N-dimethylglycine [RN:R07243];
(1b) S-adenosyl-L-methionine + N,N-dimethylglycine = S-adenosyl-L-homocysteine + betaine [RN:R07244]

R07243 R07244 R10061

S-adenosyl-L-methionine [CPD:C00019];
sarcosine [CPD:C00213];
N,N-dimethylglycine [CPD:C01026]

Cells of the oxygen-evolving halotolerant cyanobacterium Aphanocthece halophytica synthesize betaine from glycine by a three-step methylation process. The first enzyme, EC 2.1.1.156, glycine/sarcosine N-methyltransferase, leads to the formation of either sarcosine or N,N-dimethylglycine, which is further methylated to yield betaine (N,N,N-trimethylglycine) by the action of this enzyme. Both of these enzymes can catalyse the formation of N,N-dimethylglycine from sarcosine [3]. The reactions are strongly inhibited by S-adenosyl-L-homocysteine.

1  [PMID:10896953]

Nyyssola A, Kerovuo J, Kaukinen P, von Weymarn N, Reinikainen T.

Extreme halophiles synthesize betaine from glycine by methylation.

J. Biol. Chem. 275 (2000) 22196-201.

Actinopolyspora halophila, Ectothiorhodospira halochloris

2  [PMID:11319079]

Nyyssola A, Reinikainen T, Leisola M.

Characterization of glycine sarcosine N-methyltransferase and sarcosine dimethylglycine N-methyltransferase.

Appl. Environ. Microbiol. 67 (2001) 2044-50.

Ectothiorhodospira halochloris

3  [PMID:12466265]

Waditee R, Tanaka Y, Aoki K, Hibino T, Jikuya H, Takano J, Takabe T, Takabe T.

Isolation and functional characterization of N-methyltransferases that catalyze betaine synthesis from glycine in a halotolerant photosynthetic organism Aphanothece halophytica.

J. Biol. Chem. 278 (2003) 4932-42.

Actinopolyspora halophila