Record Information
Creation date2015-10-09 22:28:02 UTC
Update date2017-01-19 02:36:12 UTC
FoodComEx IDPC000079
FoodDB RecordFDB022123
Chemical Information
DescriptionHomocystine is the double-bonded form of homocysteine, but it occurs only transiently before being converted to the harmless cystathionine via a vitamin B6-dependent enzyme. Homocystine and homocysteine-cysteine mixed disulfide account for >98% of total homocysteine in plasma from healthy individuals. (PMID 11592966) Oxidation of low-density lipoprotein (LDL) is thought to be a major factor in the pathophysiology of atherosclerosis. Elevated plasma homocysteine is an accepted risk factor for atherosclerosis, and may act through LDL oxidation, although this is controversial. However, the major thiol in plasma is cysteine, which is present at concentrations approximately 10 times greater than homocysteine; therefore homocystine in plasma is insignificant, and consequently homocystine is unlikely to influence LDL oxidation in vivo. (PMID 14732479) Increasing evidence supports a role for an elevation of homocysteine in schizophrenia. It has been demonstrated that neural tube defects are related to a genetic defect in homocysteine metabolism. Sufficient intake of folic acid is believed to reduce this risk by enhancing methylation of homocysteine and its conversion to methionine, thereby compensating for this genetic defect. Plasma homocysteine levels are elevated when folate levels are in the lower half of the normal range. (PMID 16143442 ) [HMDB]
CAS Number870-93-9
Chemical FormulaC8H16N2O4S2
IUPAC name2-amino-4-[(3-amino-3-carboxypropyl)disulfanyl]butanoic acid
InChI IdentifierInChI=1S/C8H16N2O4S2/c9-5(7(11)12)1-3-15-16-4-2-6(10)8(13)14/h5-6H,1-4,9-10H2,(H,11,12)(H,13,14)
Average Molecular Weight268.354
Monoisotopic Molecular Weight268.05514839
Chemical Taxonomy
Description Belongs to the class of organic compounds known as alpha amino acids. These are amino acids in which the amino group is attached to the carbon atom immediately adjacent to the carboxylate group (alpha carbon).
KingdomOrganic compounds
Super ClassOrganic acids and derivatives
ClassCarboxylic acids and derivatives
Sub ClassAmino acids, peptides, and analogues
Direct ParentAlpha amino acids
Alternative Parents
  • Alpha-amino acid
  • Thia fatty acid
  • Dicarboxylic acid or derivatives
  • Fatty acid
  • Fatty acyl
  • Organic disulfide
  • Amino acid
  • Dialkyldisulfide
  • Sulfenyl compound
  • Carboxylic acid
  • Organic oxide
  • Organopnictogen compound
  • Primary amine
  • Organosulfur compound
  • Organooxygen compound
  • Organonitrogen compound
  • Primary aliphatic amine
  • Organic oxygen compound
  • Carbonyl group
  • Organic nitrogen compound
  • Amine
  • Hydrocarbon derivative
  • Aliphatic acyclic compound
Molecular FrameworkAliphatic acyclic compounds
External Descriptors
Physico-Chemical Properties - Experimental
Experimental logPNot Available
Experimental Water SolubilityNot Available
Melting PointNot Available
Foods of Origin
FoodContent Range AverageReference
Production Data
Production Methodcommercial
Production Method ReferenceNot Available
Production Method Reference FileNot Available
Quantity AvailableProduction upon request, up to 2 g
Delivery TimeNot Available
Storage Formsolid
Storage Conditions-80°C
StabilityNot Available
PurityNot Available
Spectral Data Upon RequestNot Available
Provider Information
Contact NameContact InstitutionContact Email
Rosa Vazquez
Commercial Vendors
AKSci C418