Cysteine is known as a sulphur-containing non-essential amino acid. Being a key constituent of glutathione, this amino acid supports a lot of vital physiological functions. For example, glutathione, made from Cysteine, Glutamic acid, and Glycine, can be found in all tissues of the human body. In the meantime, the antioxidant activity of this component is attributed particularly to the presence of Cysteine in the compound.

Chemical Structure
Structure of Cysteine

IUPAC Name: (2R)-2-amino-3-sulfanylpropanoic acid
Symbol: Three-letter code - Cys. One-letter code - C
Molecular Weight (Molar Mass): 121.15818 g/mol
Molecular Formula (Structural Formula): C3H7NO2S
Canonical SMILES: C(C(C(=O)O)N)S
Isomeric SMILES: C([C@@H](C(=O)O)N)S
CAS Number: 52-90-4
MDL Number: MFCD00064306
Melting point: 220 °C
Solubility in water: 280 g/L (25 °C); pKa - 1,96; pKb - 10,28
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: (R)-2-Amino-3-mercaptopropionic acid; beta-Mercaptoalanine; Thioserine; CySH; 3-Mercapto-L-alanine

This amino acid provides resistance to the body against all harmful effects, because it is responsible for building up white blood-cell activity. Cysteine is also necessary for the proper functioning of the skin and helps your body recover from surgery.

Cysteine is also used to produce Glutathione and Taurine. Since Cysteine is a non-essential amino acid, it can be produced by humans to satisfy their bodies' demands. If, for some reasons, your body is unable to produce this amino acid, you can find it in lots of high-protein foods like pork, chicken, eggs, milk, and cottage cheese. Vegetarians are recommended to pay more attention to eating garlic, granola and onions.

This amino acid is proved to be beneficial in numerous ways. First of all, it is essential for the detoxification and for the formation of skin. Besides, it participates in the recovery of hair and nail tissue. Then, Cysteine is used in manufacturing antioxidants and in protecting your brain and liver from damage made by alcohol and drugs consumption and even by a cigarette smoke. Finally, this amino acid helps protect against harmful toxins and damages caused by radiation.

According to various researches, other benefits of Cysteine include reducing the effects of aging on the human body. Besides, this amino acid also helps promote building muscles, healing of severe burns, and fat burning. Cysteine also encourages the activity of white blood cells. The list of benefits is virtually endless, including those like the effectiveness in treating bronchitis, angina and acute respiratory distress, and the ability to help maintain optimal health and improve immune system functioning.