Glycine/sarcosine N-methyltransferase

Glycine/sarcosine N-methyltransferase (, ApGSMT, glycine-sarcosine methyltransferase, GSMT, GMT, glycine sarcosine N-methyltransferase, S-adenosyl-L-methionine:sarcosine N-methyltransferase) is an enzyme with systematic name S-adenosyl-L-methionine:glycine(or sarcosine) N-methyltransferase (sarcosine(or N,N-dimethylglycine)-forming). This enzyme catalyses the following chemical reaction


 * 2 S-adenosyl-L-methionine + glycine $$\rightleftharpoons$$ 2 S-adenosyl-L-homocysteine + N,N-dimethylglycine (overall reaction)
 * (1a) S-adenosyl-L-methionine + glycine $$\rightleftharpoons$$ S-adenosyl-L-homocysteine + sarcosine
 * (1b) S-adenosyl-L-methionine + sarcosine $$\rightleftharpoons$$ S-adenosyl-L-homocysteine + N,N-dimethylglycine

This enzyme participates in biosynthesis of betaine from glycine in cyanobacterium Aphanocthece halophytica.