Accession NumberHMDB00575
Common_NameDL-Homocystine
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 )
Chemical_IUPAC_Name4,4'-dithiobis[2-amino-Butanoic acid]
Chemical FormulaC8H16N2O4S2
Sample Concentration1
Mass ValueNot Available
Mass Unitmg
ManufacturerQuattro_QQQ
AnalyzerTriple_Quad
DeliveryFlow_Injection
IonizationPositive
Predicted 1H NMR SpectrumDownload
Predicted 1H NMR PeaklistDownload
Predicted 13C NMR SpectrumDownload
Predicted 13C NMR PeaklistDownload
Sample ConcentrationNot Available
Mass ValueNot Available
Mass UnitNot Available
ManufacturerNot Available
FrequencyNot Available
1H NMR SpectrumNot Available
Sample ConcentrationNot Available
Mass ValueNot Available
Mass UnitNot Available
ManufacturerNot Available
FrequencyNot Available
13C NMR SpectrumNot Available
Low Energy Voltage10
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