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Record Information
StatusDetected and Quantified
Creation Date2005-11-16 15:48:42 UTC
Update Date2020-09-18 17:04:34 UTC
Secondary Accession Numbers
  • HMDB01259
Metabolite Identification
Common NameSuccinic acid semialdehyde
DescriptionSuccinic acid semialdehyde (or succinate semialdehyde) is an intermediate in the catabolism of gamma-aminobutyrate or GABA (PMID: 16435183 ). It is formed from GABA by the action of GABA transaminase, which leads to the production of succinate semialdehyde and alanine. The resulting succinate semialdehyde is further oxidized by succinate semialdehyde dehydrogenase to become succinic acid, which also yields NADPH. Under certain situations, high levels of succinate semialdehyde can function as a neurotoxin and a metabotoxin. A neurotoxin is a compound that causes damage to the brain and nerve tissues. A metabotoxin is an endogenously produced metabolite that causes adverse health effects at chronically high levels. Elevated serum levels of succinate semialdehyde are found in succinic semialdehyde dehydrogenase (SSADH) deficiency (gamma-hydroxybutyric aciduria), a rare neurometabolic disorder of gamma-aminobutyric acid (GABA) degradation. Symptoms include motor delay, hypotonia, speech delay, autistic features, seizures, and ataxia. Patients also exhibit behavioural problems such as attention deficit, hyperactivity, anxiety, or aggression (PMID: 18622364 ). Succinate semialdehyde is considered a reactive carbonyl and may lead to increased oxidative stress. This stress is believed to contribute to the formation of free radicals in the brain tissue of animal models induced with SSADH deficiency, which further leads to secondary cell damage and death. Additionally, oxidative stress may be responsible for the loss of striatal dopamine, which may contribute to the neuropathology of SSADH deficiency.
3-Formylpropanoic acidChEBI
3-Formylpropionic acidChEBI
beta-Formylpropionic acidChEBI
Semialdehyde succiniqueChEBI
Succinaldehydic acidChEBI
Succinate semialdehydeChEBI
Succinic semialdehydeKegg
4-Oxobutanoic acidGenerator
b-Formylpropionic acidGenerator
Β-formylpropionic acidGenerator
2-Formylpropionic acid ethyl esterHMDB
Butryaldehydic acidHMDB
gamma-Oxybutyric acidHMDB
Succinic semialdehyde, calcium saltHMDB
Succinic acid semialdehydeChEBI
Chemical FormulaC4H6O3
Average Molecular Weight102.0886
Monoisotopic Molecular Weight102.031694058
IUPAC Name4-oxobutanoic acid
Traditional Namesuccinic semialdehyde
CAS Registry Number692-29-5
InChI Identifier
Chemical Taxonomy
Description belongs to the class of organic compounds known as straight chain fatty acids. These are fatty acids with a straight aliphatic chain.
KingdomOrganic compounds
Super ClassLipids and lipid-like molecules
ClassFatty Acyls
Sub ClassFatty acids and conjugates
Direct ParentStraight chain fatty acids
Alternative Parents
  • Straight chain fatty acid
  • Alpha-hydrogen aldehyde
  • Monocarboxylic acid or derivatives
  • Carboxylic acid
  • Carboxylic acid derivative
  • Organic oxygen compound
  • Organic oxide
  • Hydrocarbon derivative
  • Organooxygen compound
  • Carbonyl group
  • Aldehyde
  • Aliphatic acyclic compound
Molecular FrameworkAliphatic acyclic compounds
External Descriptors

Route of exposure:


Biological location:


Naturally occurring process:


Indirect biological role:

Industrial application:

Biological role:

Physical Properties
Experimental Properties
Melting PointNot AvailableNot Available
Boiling PointNot AvailableNot Available
Water SolubilityNot AvailableNot Available
LogPNot AvailableNot Available
Predicted Properties
Water Solubility194 g/LALOGPS
pKa (Strongest Acidic)4.13ChemAxon
pKa (Strongest Basic)-7ChemAxon
Physiological Charge-1ChemAxon
Hydrogen Acceptor Count3ChemAxon
Hydrogen Donor Count1ChemAxon
Polar Surface Area54.37 ŲChemAxon
Rotatable Bond Count3ChemAxon
Refractivity22.61 m³·mol⁻¹ChemAxon
Polarizability9.26 ųChemAxon
Number of Rings0ChemAxon
Rule of FiveYesChemAxon
Ghose FilterNoChemAxon
Veber's RuleNoChemAxon
MDDR-like RuleNoChemAxon
Spectrum TypeDescriptionSplash KeyView
GC-MSGC-MS Spectrum - GC-MS (1 MEOX; 1 TMS)splash10-000i-9400000000-8e1cb554add6ed6c4e35Spectrum
GC-MSGC-MS Spectrum - GC-MS (1 MEOX; 1 TMS)splash10-000i-9300000000-f5403e2e858fded273acSpectrum
GC-MSGC-MS Spectrum - GC-MS (Non-derivatized)splash10-000i-9400000000-8e1cb554add6ed6c4e35Spectrum
GC-MSGC-MS Spectrum - GC-MS (Non-derivatized)splash10-000i-9300000000-f5403e2e858fded273acSpectrum
GC-MSGC-MS Spectrum - GC-EI-TOF (Non-derivatized)splash10-000i-9500000000-eb52f4d003b7d5b86b3dSpectrum
GC-MSGC-MS Spectrum - GC-EI-TOF (Non-derivatized)splash10-000i-9600000000-463f366ebd0be24a0283Spectrum
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (Non-derivatized) - 70eV, Positivesplash10-052f-9000000000-d9618eb947af434dcf2fSpectrum
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (1 TMS) - 70eV, Positivesplash10-05fr-9800000000-40373963cdda851ebfeaSpectrum
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 10V, Positive (Annotated)splash10-000i-9000000000-bf9ebea7e4800559c111Spectrum
LC-MS/MSLC-MS/MS Spectrum - Orbitrap 1V, negativesplash10-0udi-0900000000-64b3498f7cdd4597da6aSpectrum
LC-MS/MSLC-MS/MS Spectrum - Orbitrap 1V, negativesplash10-0udi-1900000000-9d47aab2400f1da945bcSpectrum
LC-MS/MSLC-MS/MS Spectrum - Orbitrap 2V, negativesplash10-0udi-1900000000-94e1ac309574efbe3903Spectrum
LC-MS/MSLC-MS/MS Spectrum - Orbitrap 2V, negativesplash10-0udi-3900000000-7ec96b67f820176c39d3Spectrum
LC-MS/MSLC-MS/MS Spectrum - Orbitrap 3V, negativesplash10-0udi-5900000000-7708b3a1c05b69363aa9Spectrum
LC-MS/MSLC-MS/MS Spectrum - Orbitrap 3V, negativesplash10-0zfr-8900000000-12726b727f621ac971b7Spectrum
LC-MS/MSLC-MS/MS Spectrum - n/a 7V, negativesplash10-0089-9000000000-9eb7dd16da8275702c75Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Positivesplash10-000i-9200000000-e31b8066f970e1c178d1Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Positivesplash10-052u-9000000000-76526f6c67d7a67c1d07Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Positivesplash10-0a4l-9000000000-70e85383e59b46bc429fSpectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Negativesplash10-0udi-5900000000-f1c2507387f92b6e1e3fSpectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Negativesplash10-0zgi-9400000000-ba1b880a90d3ace8beeeSpectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Negativesplash10-052f-9000000000-971836bb1672ad33106eSpectrum
1D NMR1H NMR SpectrumNot AvailableSpectrum
2D NMR[1H,13C] 2D NMR SpectrumNot AvailableSpectrum
Biological Properties
Cellular Locations
  • Cytoplasm
  • Extracellular
  • Membrane
  • Mitochondria
Biospecimen Locations
  • Cerebrospinal Fluid (CSF)
  • Urine
Tissue Locations
  • Testis
Normal Concentrations
Cerebrospinal Fluid (CSF)Detected and Quantified28.5 (24.0-33.0) uMAdult (>18 years old)BothNormal
    • Geigy Scientific ...
UrineDetected and Quantified0.35 (0.14-0.54) umol/mmol creatinineAdult (>18 years old)MaleNormal details
UrineDetected and Quantified0.39 (0.28-0.51) umol/mmol creatinineAdult (>18 years old)FemaleNormal details
UrineDetected but not QuantifiedNot QuantifiedNot SpecifiedNot SpecifiedNormal details
Abnormal Concentrations
Not Available
Associated Disorders and Diseases
Disease ReferencesNone
Associated OMIM IDsNone
DrugBank IDDBMET01476
Phenol Explorer Compound IDNot Available
FooDB IDFDB022516
KNApSAcK IDC00019682
Chemspider ID1080
KEGG Compound IDC00232
BiGG ID34331
Wikipedia LinkSuccinic semialdehyde
PubChem Compound1112
PDB IDNot Available
ChEBI ID16265
Food Biomarker OntologyNot Available
MarkerDB ID
Synthesis ReferenceBruce, R.; Sims, K.; Pitts, F. N., Jr. Synthesis and purification of succinic semialdehyde. Analytical Biochemistry (1971), 41(1), 271-3.
Material Safety Data Sheet (MSDS)Download (PDF)
General References
  1. Du L, Musson DG, Wang AQ: Stability studies of vorinostat and its two metabolites in human plasma, serum and urine. J Pharm Biomed Anal. 2006 Nov 16;42(5):556-64. Epub 2006 Jul 5. [PubMed:16824724 ]
  2. Du L, Musson DG, Wang AQ: High turbulence liquid chromatography online extraction and tandem mass spectrometry for the simultaneous determination of suberoylanilide hydroxamic acid and its two metabolites in human serum. Rapid Commun Mass Spectrom. 2005;19(13):1779-87. [PubMed:15945019 ]
  3. Hinshelwood A, McGarvie G, Ellis EM: Substrate specificity of mouse aldo-keto reductase AKR7A5. Chem Biol Interact. 2003 Feb 1;143-144:263-9. [PubMed:12604212 ]
  4. Lee BC, Choe YS, Chi DY, Paik JY, Lee KH, Choi Y, Kim BT: 8-cyclopentadienyltricarbonyl 99mtc 8-oxooctanoic acid: a novel radiotracer for evaluation of medium chain fatty acid metabolism in the liver. Bioconjug Chem. 2004 Jan-Feb;15(1):121-7. [PubMed:14733591 ]
  5. Parise RA, Holleran JL, Beumer JH, Ramalingam S, Egorin MJ: A liquid chromatography-electrospray ionization tandem mass spectrometric assay for quantitation of the histone deacetylase inhibitor, vorinostat (suberoylanilide hydroxamicacid, SAHA), and its metabolites in human serum. J Chromatogr B Analyt Technol Biomed Life Sci. 2006 Aug 18;840(2):108-15. Epub 2006 May 24. [PubMed:16725386 ]
  6. Struys EA, Jansen EE, Gibson KM, Jakobs C: Determination of the GABA analogue succinic semialdehyde in urine and cerebrospinal fluid by dinitrophenylhydrazine derivatization and liquid chromatography-tandem mass spectrometry: application to SSADH deficiency. J Inherit Metab Dis. 2005;28(6):913-20. [PubMed:16435183 ]
  7. Knerr I, Gibson KM, Jakobs C, Pearl PL: Neuropsychiatric morbidity in adolescent and adult succinic semialdehyde dehydrogenase deficiency patients. CNS Spectr. 2008 Jul;13(7):598-605. [PubMed:18622364 ]


General function:
Involved in 4-aminobutyrate transaminase activity
Specific function:
Catalyzes the conversion of gamma-aminobutyrate and L-beta-aminoisobutyrate to succinate semialdehyde and methylmalonate semialdehyde, respectively. Can also convert delta-aminovalerate and beta-alanine.
Gene Name:
Uniprot ID:
Molecular weight:
gamma-Aminobutyric acid + Oxoglutaric acid → Succinic acid semialdehyde + L-Glutamic aciddetails
General function:
Involved in oxidoreductase activity
Specific function:
Catalyzes one step in the degradation of the inhibitory neurotransmitter gamma-aminobutyric acid (GABA).
Gene Name:
Uniprot ID:
Molecular weight:
Succinic acid semialdehyde + NAD + Water → Succinic acid + NADHdetails
Succinic acid semialdehyde + NAD + Water → Succinic acid + NADH + Hydrogen Iondetails
General function:
Energy production and conversion
Specific function:
Catalyzes the NADPH-dependent reduction of succinic semialdehyde to gamma-hydroxybutyrate. May have an important role in producing the neuromodulator gamma-hydroxybutyrate (GHB). Has broad substrate specificity. Has NADPH-dependent aldehyde reductase activity towards 2-carboxybenzaldehyde, 2-nitrobenzaldehyde and pyridine-2-aldehyde (in vitro). Can reduce 1,2-naphthoquinone and 9,10-phenanthrenequinone (in vitro). Can reduce the dialdehyde protein-binding form of aflatoxin B1 (AFB1) to the non-binding AFB1 dialcohol. May be involved in protection of liver against the toxic and carcinogenic effects of AFB1, a potent hepatocarcinogen.
Gene Name:
Uniprot ID:
Molecular weight:
4-Hydroxybutyric acid + NADP → Succinic acid semialdehyde + NADPHdetails
General function:
Involved in oxidoreductase activity
Specific function:
Catalyzes the cofactor-independent reversible oxidation of gamma-hydroxybutyrate (GHB) to succinic semialdehyde (SSA) coupled to reduction of 2-ketoglutarate (2-KG) to D-2-hydroxyglutarate (D-2-HG). D,L-3-hydroxyisobutyrate and L-3-hydroxybutyrate (L-3-OHB) are also substrates for HOT with 10-fold lower activities.
Gene Name:
Uniprot ID:
Molecular weight:
4-Hydroxybutyric acid + Oxoglutaric acid → Succinic acid semialdehyde + D-2-Hydroxyglutaric aciddetails