S-Methylmethionine
S-Methylmethionine
Chemical compound
S-Methylmethionine (SMM) is a derivative of methionine with the chemical formula (CH3)2S+CH2CH2CH(NH3+)CO2−. This cation is a naturally-occurring intermediate in many biosynthetic pathways owing to the sulfonium functional group. It is biosynthesized from L-methionine and S-adenosylmethionine by the enzyme methionine S-methyltransferase. S-methylmethionine is particularly abundant in plants, being more abundant than methionine.[2]
S-Methylmethionine is sometimes referred to as vitamin U,[3] but it is not considered a true vitamin. The term was coined in 1950 by Garnett Cheney for uncharacterized anti-ulcerogenic[4] factors in raw cabbage juice that may help speed healing of peptic ulcers.