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L-cystine

Structure via PubChem · Public domain (PubChem)

EntityQ408626· pop 36· linked from 226 articles

Also known as (-)-cystine, cystine, L-dicysteine, (R,R)-3,3'-dithiobis(2-aminopropanoic acid), L-alpha-Diamino-beta-dithiolactic acid, β,β'-dithiodialanine, L-Dicysteine, Cystine

Cystine is the oxidized derivative of the amino acid cysteine and has the formula (SCH2CH(NH2)CO2H)2. It is a white solid that is poorly soluble in water. As a residue in proteins, cystine serves two functions: a site of redox reactions and a mechanical linkage that allows proteins to retain their three-dimensional structure.

Chemical data

Formula
C6H12N2O4S2
Molecular weight
240.3 g/mol
IUPAC name
(2R)-2-azaniumyl-3-[[(2R)-2-azaniumyl-2-carboxylatoethyl]disulfanyl]propanoate
SMILES
C([C@@H](C(=O)[O-])[NH3+])SSC[C@@H](C(=O)[O-])[NH3+]
InChIKey
LEVWYRKDKASIDU-IMJSIDKUSA-N
XLogP
-5
Polar surface area
186 Ų
H-bond donors
2
H-bond acceptors
6
Formal charge
0

via PubChem

~5 min read

Encyclopedic overview

10 sections
Contents
  • Formation and reactions
  • Structure
  • Occurrence
  • History
  • Redox
  • Cystine-based disorders
  • Biological transport
  • See also
  • References
  • External links

Cystine is the oxidized derivative of the amino acid cysteine and has the formula (SCH2CH(NH2)CO2H)2. It is a white solid that is poorly soluble in water. As a residue in proteins, cystine serves two functions: a site of redox reactions and a mechanical linkage that allows proteins to retain their three-dimensional structure.

==Formation and reactions== ===Structure=== Cystine is the disulfide derived from the amino acid cysteine. The conversion can be viewed as an oxidation:

Excerpted from Wikipedia’s “L-cystine” article, available under the CC BY-SA 4.0 licence.

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