Methionine

J. H. Muller, a researcher at Columbia University in New York, discovered a new amino acid Methionine back in 1922. He isolated it, but submitted an incorrect summation formula, which was corrected only 3 years later by his fellow researcher Odake from Japan. Odake was the one who gave a name to the amino acid - 'Methionine'. Finally, in another three years, Barger and Coyne identified the structure of Methionine.

Chemical Structure
Structure of L-Methionine

IUPAC Name: (2S)-2-Amino-4-methylsulfanylbutanoic acid
Symbol: Three-letter code - Met. One-letter code - M
Molecular Weight (Molar Mass): 149.21134 g/mol
Molecular Formula (Structural Formula): C5H11NO2S
Canonical SMILES: CSCCC(C(=O)O)N
Isomeric SMILES: CSCC[C@@H](C(=O)O)N
InChIKey Identifier: FFEARJCKVFRZRR-XWEZEGGSDQ
CAS Number: 63-68-3
MDL Number: MFCD00063097
Melting point: 284 °C
Solubility in water: 53.7 g/1 L (20 °C); pKa - 2,28; pKb - 9,21
IR and H1 NMR spectrum: n/a
MSDS (Material Safety Data Sheet): n/a
2D Molfile: Get the molfile
3D PDB file: Get the PDB file
Other names: L-2-Amino-4-(methylthio)butyric acid; S-Methionine; L-alpha-Amino-gamma-methylmercaptobutyric acid; (S)-2-Amino-4-(methylthio)butanoic acid; L-alpha-Amino-gamma-methylthiobutyric acid; L-gamma-Methylthio-alpha-aminobutyric acid; L-2-Amino-4-methylthiobutanoic acid


To manufacture DL-methionine, methyl mercaptan is reacted with acrolein to produce an intermediate, methyl mercaptan-propionaldehyde (MMP). MMP is then further reacted with hydrogen cyanide to produce methionine.

In short words, Methionine is a sulfur-containing proteinogenic amino acid, acting as an intermediate in the biosynthesis of different phospholipids. It is important in single-carbon metabolism and helps the detoxification in the liver. Meanwhile, improper conversion of Methionine can lead to atherosclerosis. In other words, it is one of the essential amino acids necessary for your health, but the problem is that it cannot be produced in the body, and, as a result, you need to provide it through your diet.

Methionine is actually a supplier of sulfur and a few other compounds that our body needs for normal metabolism and growth. As you know, sulfur is a key element and very important to our life. If you lack an adequate intake of sulfur, your body will be unable to produce and to utilize some antioxidant nutrients. Therefore, Methionine is a very valuable nutritional compound providing numerous benefits for your body. For example, European doctors are using it to treat such conditions as depression, inflammation, liver diseases, and some muscle pains. This amino acid is particularly beneficial for people suffering from estrogen dominance, i.e. the amount of estrogen in the body is too high compared to that of progesterone. Besides, women taking oral contraceptives can also find Methionine very helpful - considering that estrogen is cleared through the liver, it is better to enhance the liver function to reduce the body's estrogen load.

Normally, most people do not need to take the Methionine supplementation when in good health. Naturally, you can get some of this amino acid from food like meat, fish, and dairy products. As for vegans and people who follow the low-protein diet, they can obtain it from whole grains.