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Record Information
StatusDetected and Quantified
Creation Date2005-11-16 15:48:42 UTC
Update Date2020-02-26 21:22:33 UTC
Secondary Accession Numbers
  • HMDB00745
Metabolite Identification
Common NameHomocarnosine
DescriptionHomocarnosine is a normal human metabolite, the brain-specific dipeptide of gamma-aminobutyric acid (GABA) and histidine. (PMID 1266573 ). Increased concentration of CSF homocarnosine has been found in familial spastic paraplegia. (PMID 842287 ). Homocarnosinosis (an inherited disorder, OMIM 236130 ) is characterized by an elevated level of the dipeptide homocarnosine (Hca) in the Cerebrospinal fluid (CSF) and the brain and by carnosinuria and serum carnosinase deficiency, and can co-exist with paraplegia, retinitis pigmentosa, and a progressive mental deficiency. (PMID 3736769 ). In glial tumors of human brain the content of homocarnosine has been found to be lower than in brain tissue (PMID 1032224 ), while an increase in content of homocarnosine was observed in brain tissue of animals under experimental trauma of cranium. (PMID 1025883 ).
gamma-Aminobutyryl histidineKegg
g-Aminobutyryl histidineGenerator
Γ-aminobutyryl histidineGenerator
Homocarnosine sulfateHMDB
Chemical FormulaC10H16N4O3
Average Molecular Weight240.259
Monoisotopic Molecular Weight240.122240398
IUPAC Name(2S)-2-(4-aminobutanamido)-3-(1H-imidazol-4-yl)propanoic acid
Traditional Name(2S)-2-(4-aminobutanamido)-3-(1H-imidazol-4-yl)propanoic acid
CAS Registry Number3650-73-5
InChI Identifier
Chemical Taxonomy
Description belongs to the class of organic compounds known as hybrid peptides. Hybrid peptides are compounds containing at least two different types of amino acids (alpha, beta, gamma, delta) linked to each other through a peptide bond.
KingdomOrganic compounds
Super ClassOrganic acids and derivatives
Sub ClassHybrid peptides
Direct ParentHybrid peptides
Alternative Parents
  • Hybrid peptide
  • Histidine or derivatives
  • N-acyl-alpha-amino acid
  • N-acyl-alpha amino acid or derivatives
  • N-acyl-l-alpha-amino acid
  • Gamma amino acid or derivatives
  • Alpha-amino acid or derivatives
  • Imidazolyl carboxylic acid derivative
  • N-acyl-amine
  • Fatty amide
  • Fatty acyl
  • Azole
  • Imidazole
  • Heteroaromatic compound
  • Amino acid
  • Amino acid or derivatives
  • Secondary carboxylic acid amide
  • Carboxamide group
  • Carboxylic acid derivative
  • Carboxylic acid
  • Azacycle
  • Organoheterocyclic compound
  • Monocarboxylic acid or derivatives
  • Organic oxygen compound
  • Hydrocarbon derivative
  • Amine
  • Organic nitrogen compound
  • Organic oxide
  • Carbonyl group
  • Primary amine
  • Organooxygen compound
  • Primary aliphatic amine
  • Organopnictogen compound
  • Organonitrogen compound
  • Aromatic heteromonocyclic compound
Molecular FrameworkAromatic heteromonocyclic compounds
External Descriptors


Biological location:


Biological role:

Physical Properties
Experimental Properties
Melting PointNot AvailableNot Available
Boiling PointNot AvailableNot Available
Water SolubilityNot AvailableNot Available
LogPNot AvailableNot Available
Predicted Properties
Water Solubility7.37 g/LALOGPS
pKa (Strongest Acidic)3.45ChemAxon
pKa (Strongest Basic)9.99ChemAxon
Physiological Charge0ChemAxon
Hydrogen Acceptor Count5ChemAxon
Hydrogen Donor Count4ChemAxon
Polar Surface Area121.1 ŲChemAxon
Rotatable Bond Count7ChemAxon
Refractivity59.75 m³·mol⁻¹ChemAxon
Polarizability24.49 ųChemAxon
Number of Rings1ChemAxon
Rule of FiveYesChemAxon
Ghose FilterNoChemAxon
Veber's RuleNoChemAxon
MDDR-like RuleNoChemAxon
Spectrum TypeDescriptionSplash KeyView
GC-MSGC-MS Spectrum - GC-EI-TOF (Pegasus III TOF-MS system, Leco; GC 6890, Agilent Technologies) (3 TMS)splash10-0udi-1920000000-a03e2c4f8b2c9d6a1635Spectrum
GC-MSGC-MS Spectrum - GC-EI-TOF (Pegasus III TOF-MS system, Leco; GC 6890, Agilent Technologies) (3 TMS)splash10-0udi-0920000000-e48ce78a12a5f4834686Spectrum
GC-MSGC-MS Spectrum - GC-EI-TOF (Pegasus III TOF-MS system, Leco; GC 6890, Agilent Technologies) (3 TMS)splash10-0fk9-9710000000-32bfa6992d5a80f09a36Spectrum
GC-MSGC-MS Spectrum - GC-EI-TOF (Non-derivatized)splash10-0udi-1920000000-a03e2c4f8b2c9d6a1635Spectrum
GC-MSGC-MS Spectrum - GC-EI-TOF (Non-derivatized)splash10-0udi-0920000000-e48ce78a12a5f4834686Spectrum
GC-MSGC-MS Spectrum - GC-EI-TOF (Non-derivatized)splash10-0fk9-9710000000-32bfa6992d5a80f09a36Spectrum
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (Non-derivatized) - 70eV, Positivesplash10-001i-9410000000-343b9389cd3a9e7656c5Spectrum
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (1 TMS) - 70eV, Positivesplash10-000t-9620000000-f0df8a34f8155fd39194Spectrum
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 10V, Positive (Annotated)splash10-0a4i-0910000000-b804d40537827898f4afSpectrum
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 25V, Positive (Annotated)splash10-03di-5900000000-26897d5ae957a9cb6b35Spectrum
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 40V, Positive (Annotated)splash10-03e9-9300000000-291e9d04c321015b9241Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QQ (API3000, Applied Biosystems) 10V, Negativesplash10-000i-0090000000-352076fb2d925fdf8d3dSpectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QQ (API3000, Applied Biosystems) 20V, Negativesplash10-0f79-0960000000-6efcaf43e71ab44953faSpectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QQ (API3000, Applied Biosystems) 30V, Negativesplash10-03di-0900000000-4122cf33c566cb50775cSpectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QQ (API3000, Applied Biosystems) 40V, Negativesplash10-03di-4900000000-499817ec7737f4f71264Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QQ (API3000, Applied Biosystems) 50V, Negativesplash10-001i-9300000000-5e2839e6bf4597a45ad3Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QQ (API3000, Applied Biosystems) 10V, Positivesplash10-0a4l-0980000000-a0e96805123eef741d16Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QQ (API3000, Applied Biosystems) 20V, Positivesplash10-0a4i-0900000000-bd852312bcfa93da513dSpectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QQ (API3000, Applied Biosystems) 30V, Positivesplash10-03di-2900000000-b0c96a1971d8e230da77Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QQ (API3000, Applied Biosystems) 40V, Positivesplash10-03di-6900000000-086dfb0ef83a3e18d4c9Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QQ (API3000, Applied Biosystems) 50V, Positivesplash10-03yi-9300000000-cb8906cb50227e7ec5b5Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-IT (LC/MSD Trap XCT, Agilent Technologies) , Positivesplash10-0a4i-0900000000-e3a22c7580a368d6849bSpectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-IT (LC/MSD Trap XCT, Agilent Technologies) , Positivesplash10-03di-0900000000-eab8c998b760a5bc2d46Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-IT (LC/MSD Trap XCT, Agilent Technologies) , Positivesplash10-000x-9000000000-d32f932f9d139b180e07Spectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QTOF (UPLC Q-Tof Premier, Waters) , Negativesplash10-0iki-0930000000-80b81755ee1a773ed3bbSpectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QQ , negativesplash10-000i-0090000000-5b43effb3dfed505b61bSpectrum
LC-MS/MSLC-MS/MS Spectrum - LC-ESI-QQ , negativesplash10-0f79-0960000000-52b5a3c482216dc5067dSpectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Positivesplash10-00dl-1490000000-abafa225b4c4cc6f1314Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Positivesplash10-0bti-5930000000-d1e289dfa041a96af6e4Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Positivesplash10-052f-9400000000-3dc5fad146dc39014458Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Negativesplash10-000i-0490000000-dfebe908fd4392611bb6Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Negativesplash10-0uej-3940000000-c7f4d398999fc797b544Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Negativesplash10-0f7o-9500000000-f8ed9a520a7d500d0c1eSpectrum
1D NMR1H NMR SpectrumNot AvailableSpectrum
2D NMR[1H,13C] 2D NMR SpectrumNot AvailableSpectrum
Biological Properties
Cellular Locations
  • Cytoplasm (predicted from logP)
Biospecimen Locations
  • Cerebrospinal Fluid (CSF)
  • Urine
Tissue Locations
  • Brain
  • Prostate
Normal Concentrations
Cerebrospinal Fluid (CSF)Detected and Quantified2.70 +/- 2.50 uMAdult (>18 years old)BothNormal
    • Geigy Scientific ...
UrineDetected and Quantified0.26 umol/mmol creatinineAdult (>18 years old)BothNormal details
Abnormal Concentrations
Not Available
Associated Disorders and Diseases
Disease ReferencesNone
Associated OMIM IDsNone
DrugBank IDNot Available
Phenol Explorer Compound IDNot Available
FoodDB IDFDB022217
KNApSAcK IDNot Available
Chemspider ID8418848
KEGG Compound IDC00884
BioCyc IDCPD-12185
BiGG IDNot Available
Wikipedia LinkNot Available
PubChem Compound10243361
PDB IDNot Available
ChEBI ID85981
Food Biomarker OntologyNot Available
VMH IDNot Available
Synthesis ReferenceNagai, Kineshiro; Nagai, Kinuko. Treating inflammatory diseases with homocarnosine. U.S. (1985), 7 pp.
Material Safety Data Sheet (MSDS)Download (PDF)
General References
  1. Petroff OA, Mattson RH, Behar KL, Hyder F, Rothman DL: Vigabatrin increases human brain homocarnosine and improves seizure control. Ann Neurol. 1998 Dec;44(6):948-52. [PubMed:9851440 ]
  2. Petroff OA, Hyder F, Mattson RH, Rothman DL: Topiramate increases brain GABA, homocarnosine, and pyrrolidinone in patients with epilepsy. Neurology. 1999 Feb;52(3):473-8. [PubMed:10025774 ]
  3. Lenney JF, Peppers SC, Kucera CM, Sjaastad O: Homocarnosinosis: lack of serum carnosinase is the defect probably responsible for elevated brain and CSF homocarnosine. Clin Chim Acta. 1983 Aug 15;132(2):157-65. [PubMed:6616870 ]
  4. Rothman DL, Behar KL, Prichard JW, Petroff OA: Homocarnosine and the measurement of neuronal pH in patients with epilepsy. Magn Reson Med. 1997 Dec;38(6):924-9. [PubMed:9402193 ]
  5. Pearl PL, Novotny EJ, Acosta MT, Jakobs C, Gibson KM: Succinic semialdehyde dehydrogenase deficiency in children and adults. Ann Neurol. 2003;54 Suppl 6:S73-80. [PubMed:12891657 ]
  6. Tell G, Bohlen P, Schechter PJ, Koch-Weser J, Agid Y, Bonnet AM, Coquillat G, Chazot G, Fischer C: Treatment of Huntington disease with gamma-acetylenic GABA an irreversible inhibitor of GABA-transaminase: increased CSF GABA and homocarnosine without clinical amelioration. Neurology. 1981 Feb;31(2):207-11. [PubMed:6258106 ]
  7. Promyslov MSh, Mirzoian RA: [Homocarnosine metabolism in brain tissue]. Vopr Biokhim Mozga. 1976;11:71-7. [PubMed:1032224 ]
  8. Iurovskii SL, Orlov VI, Pogorelova TN, Drukker NA, Madan M: [Homocarnosine of the amniotic fluid as an indicator of fetal cerebral lesions]. Akush Ginekol (Mosk). 1989 Sep;(9):45-7. [PubMed:2596637 ]
  9. Menachem EB, Persson LI, Schechter PJ, Haegele KD, Huebert N, Hardenberg J, Dahlgren L, Mumford JP: Effects of single doses of vigabatrin on CSF concentrations of GABA, homocarnosine, homovanillic acid and 5-hydroxyindoleacetic acid in patients with complex partial epilepsy. Epilepsy Res. 1988 Mar-Apr;2(2):96-101. [PubMed:3143561 ]
  10. Perry TL, Kish SJ, Sjaastad O, Gjessing LR, Nesbakken R, Schrader H, Loken AC: Homocarnosinosis: increased content of homocarnosine and deficiency of homocarnosinase in brain. J Neurochem. 1979 Jun;32(6):1637-40. [PubMed:448356 ]
  11. Promyslov MSh, Mirzoian RA: [Study of homocarnosine metabolism in the brain tissue in diseases of the nervous system]. Vopr Med Khim. 1976 Mar-Apr;22(2):209-12. [PubMed:1025883 ]
  12. Manyam BV, Bhatt MH, Moore WD, Devleschoward AB, Anderson DR, Calne DB: Bilateral striopallidodentate calcinosis: cerebrospinal fluid, imaging, and electrophysiological studies. Ann Neurol. 1992 Apr;31(4):379-84. [PubMed:1586138 ]
  13. Sreekumar A, Poisson LM, Rajendiran TM, Khan AP, Cao Q, Yu J, Laxman B, Mehra R, Lonigro RJ, Li Y, Nyati MK, Ahsan A, Kalyana-Sundaram S, Han B, Cao X, Byun J, Omenn GS, Ghosh D, Pennathur S, Alexander DC, Berger A, Shuster JR, Wei JT, Varambally S, Beecher C, Chinnaiyan AM: Metabolomic profiles delineate potential role for sarcosine in prostate cancer progression. Nature. 2009 Feb 12;457(7231):910-4. doi: 10.1038/nature07762. [PubMed:19212411 ]
  14. Sjaastad O, Berstad J, Gjesdahl P, Gjessing L: Homocarnosinosis. 2. A familial metabolic disorder associated with spastic paraplegia, progressive mental deficiency, and retinal pigmentation. Acta Neurol Scand. 1976 Apr;53(4):275-90. [PubMed:1266573 ]
  15. Sjaastad O, Gjessing L, Berstad JR, Gjesdahl P: Homocarnosinosis. 3. Spinal fluid amino acids in familial spastic paraplegia. Acta Neurol Scand. 1977 Feb;55(2):158-62. [PubMed:842287 ]
  16. Lunde HA, Gjessing LR, Sjaastad O: Homocarnosinosis: influence of dietary restriction of histidine. Neurochem Res. 1986 Jun;11(6):825-38. [PubMed:3736769 ]


General function:
Involved in metallopeptidase activity
Specific function:
Preferential hydrolysis of the beta-Ala-|-His dipeptide (carnosine), and also anserine, Xaa-|-His dipeptides and other dipeptides including homocarnosine
Gene Name:
Uniprot ID:
Molecular weight:
General function:
Involved in catalytic activity
Specific function:
Catalyzes the synthesis of carnosine and homocarnosine. Carnosine is synthesized more efficiently than homocarnosine.
Gene Name:
Uniprot ID:
Molecular weight:
Adenosine triphosphate + L-Histidine + gamma-Aminobutyric acid → Adenosine monophosphate + Pyrophosphate + Homocarnosinedetails