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Cysteine

Synonym(s)

  • Cys
  • cysteine (substance)
  • L-cysteine

Definition(s)

A non-essential sulfur-containing amino acid in humans, related to cystine, cysteine is important for protein synthesis, detoxification, and diverse metabolic functions. Found in beta-keratin, the main protein in nails, skin, and hair, cysteine is important in collagen production, as well as skin elasticity and texture. Also required in the manufacture of amino acid taurine, cysteine is a component of the antioxidant glutathione, and plays a role in the metabolism of essential biochemicals such as coenzyme A, heparin, and biotin.

Definition from: NCI via Unified Medical Language SystemThis link leads to a site outside Genetics Home Reference. at the National Library of Medicine

Amino acid with side chain -CH2SH.

Definition from: NCI via Unified Medical Language SystemThis link leads to a site outside Genetics Home Reference. at the National Library of Medicine

Primary amino acid with the side group -CH2SH, capable of forming disulfide bonds (cystine) with other cysteine residues to stabilize protein tertiary and oligomeric structure.

Definition from: CRISP Thesaurus via Unified Medical Language SystemThis link leads to a site outside Genetics Home Reference. at the National Library of Medicine

See also Understanding Medical Terminology.

 
Published: August 25, 2014