Definition of methionine
: a crystalline sulfur-containing essential amino acid C5H11NO2S that occurs in the levorotatory form as a constituent of many proteins
Recent Examples of methionine from the Web
Plants use sulfur to manufacture cysteine and methionine, two amino acids important for producing protein.
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Origin and Etymology of methionine
International Scientific Vocabulary, from methyl + thion- + 2-ine
First Known Use: 1928See Words from the same year
Medical Definition of methionine
: a crystalline sulfur-containing essential amino acid C5H11NO2S that occurs in the L-form as a constituent of many proteins (as casein and egg albumin), that is important especially as a source of sulfur for the biosynthesis of cysteine and as a source of methyl groups for transmethylation reactions (as in the biosynthesis of choline, creatine, and adrenaline), and that is used as a dietary supplement for human beings and their domestic mammals and poultry and in the treatment of fatty infiltration of the liver—abbreviation Met
Learn More about methionine
Britannica.com: Encyclopedia article about methionine
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