Definition of cysteine in English:

cysteine

noun

Biochemistry
  • A sulfur-containing amino acid that occurs in keratins and other proteins, often in the form of cystine, and is a constituent of many enzymes.

    • ‘The gelatinase activity was due to metalloproteinases and not cysteine or serine proteinases.’
    • ‘Whey proteins are also rich in the sulfur-containing amino acids cysteine and methionine.’
    • ‘Most of the sulfate substrate comes from sulfoxidation of the amino acid cysteine.’
    • ‘As long as the supply of methionine is adequate, cysteine is considered as nonessential.’
    • ‘The integration of reduced sulphur into the amino acid cysteine is a central step in the assimilation of inorganic sulphur.’

Origin

Late 19th century: from cystine + -eine (variant of -ine).

Pronunciation:

cysteine

/ˈsisˌtēn//ˈsistəˌēn/