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Record Information
Version4.0
StatusDetected and Quantified
Creation Date2005-11-16 15:48:42 UTC
Update Date2017-12-07 01:12:25 UTC
HMDB IDHMDB0000186
Secondary Accession Numbers
  • HMDB00186
  • HMDB05761
Metabolite Identification
Common NameAlpha-Lactose
Descriptionalpha-Lactose is the major sugar present in milk and the main source of energy supplied to the newborn mammalian in its mother's milk. Lactose is also an important osmotic regulator of lactation. It is digested by the intestinal lactase (EC 3.2.1.108), an enzyme expressed in newborns. Its activity declines following weaning. As a result, adult mammals are normally lactose-intolerant and more than 75% of the human adult population suffers from lactase deficiency. Lactase deficiency is present in up to 80 percent of blacks and Latinos, and up to 100 percent of American Indians and Asians. Persons with lactose intolerance are unable to digest significant amounts of lactose. Common symptoms include abdominal pain and bloating, excessive flatus, and watery stool following the ingestion of foods containing lactose. A sizable number of adults believe they are lactose intolerant but do not actually have impaired lactose digestion, and some persons with lactase deficiency can tolerate moderate amounts of ingested lactose. A diagnosis of lactose intolerance can usually be made with a careful history supported by dietary manipulation. If necessary, diagnosis can be confirmed by using a breath hydrogen or lactose tolerance test. These mostly uncomfortable symptoms of lactose maldigestion are blamed for a variably dairy consumption. There is, however, emerging evidence that certain lactic acid-producing bacteria, which selectively consume prebiotics, may be beneficial against some lower intestinal diseases. Lactose maldigestion and lactose should perhaps be re-evaluated as a potential provider of such a prebiotic. Treatment consists primarily of avoiding lactose-containing foods. Lactase enzyme supplements may be helpful. The degree of lactose malabsorption varies greatly among patients with lactose intolerance, but most of them can ingest up to 350 mL of milk daily without symptoms. Lactose-intolerant patients must ensure adequate calcium intake. (PMID: 13130292 , 12216958 , 12197838 , 12018807 ). Lactose in the urine is a biomarker for the consumption of milk.
Structure
Thumb
SynonymsNot Available
Chemical FormulaC12H22O11
Average Molecular Weight342.2965
Monoisotopic Molecular Weight342.116211546
IUPAC Name(2R,3R,4S,5R,6S)-2-(hydroxymethyl)-6-{[(2R,3S,4R,5R,6S)-4,5,6-trihydroxy-2-(hydroxymethyl)oxan-3-yl]oxy}oxane-3,4,5-triol
Traditional Nameα-lactose
CAS Registry Number63-42-3
SMILES
OC[C@H]1O[C@@H](O[C@H]2[C@H](O)[C@@H](O)[C@@H](O)O[C@@H]2CO)[C@H](O)[C@@H](O)[C@H]1O
InChI Identifier
InChI=1S/C12H22O11/c13-1-3-5(15)6(16)9(19)12(22-3)23-10-4(2-14)21-11(20)8(18)7(10)17/h3-20H,1-2H2/t3-,4-,5+,6+,7-,8-,9-,10-,11+,12+/m1/s1
InChI KeyGUBGYTABKSRVRQ-XLOQQCSPSA-N
Chemical Taxonomy
ClassificationNot classified
Ontology
Disposition

Biological Location:

  Subcellular:

  Biofluid and excreta:

  Organ and components:

  Tissue and substructures:

  Cell and elements:

    Element:

Source:

Process

Naturally occurring process:

  Biological process:

    Biochemical pathway:

Role

Indirect biological role:

Physical Properties
StateSolid
Experimental Properties
PropertyValueReference
Melting Point201 - 202 °CNot Available
Boiling PointNot AvailableNot Available
Water Solubility195 mg/mL at 20 °CNot Available
LogPNot AvailableNot Available
Predicted Properties
PropertyValueSource
Water Solubility586 g/LALOGPS
logP-3ALOGPS
logP-4.7ChemAxon
logS0.23ALOGPS
pKa (Strongest Acidic)11.25ChemAxon
pKa (Strongest Basic)-3ChemAxon
Physiological Charge0ChemAxon
Hydrogen Acceptor Count11ChemAxon
Hydrogen Donor Count8ChemAxon
Polar Surface Area189.53 ŲChemAxon
Rotatable Bond Count4ChemAxon
Refractivity68.34 m³·mol⁻¹ChemAxon
Polarizability30.96 ųChemAxon
Number of Rings2ChemAxon
Bioavailability0ChemAxon
Rule of FiveYesChemAxon
Ghose FilterYesChemAxon
Veber's RuleYesChemAxon
MDDR-like RuleYesChemAxon
Spectra
Spectra
Spectrum TypeDescriptionSplash Key
GC-MSGC-MS Spectrum - GC-EI-TOF (Pegasus III TOF-MS system, Leco; GC 6890, Agilent Technologies) (8 TMS)splash10-0uxs-0972000000-af8ca1bf1faa3d01a08dView in MoNA
GC-MSGC-MS Spectrum - GC-EI-TOF (Pegasus III TOF-MS system, Leco; GC 6890, Agilent Technologies) (8 TMS; 1 MEOX)splash10-00di-9741000000-a61bf0223a1683f0402eView in MoNA
GC-MSGC-MS Spectrum - GC-EI-TOF (Pegasus III TOF-MS system, Leco; GC 6890, Agilent Technologies) (8 TMS; 1 MEOX)splash10-00di-9641000000-12611bfab50cb066e8afView in MoNA
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (Non-derivatized) - 70eV, Positivesplash10-03e9-4897000000-332d470623cd7f1e1cedView in MoNA
Predicted GC-MSPredicted GC-MS Spectrum - GC-MS (4 TMS) - 70eV, Positivesplash10-014i-3513539000-d702fa4adb45f44530b6View in MoNA
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 10V, Positive (Annotated)splash10-03di-0901000000-bcb7aaa42261d980d488View in MoNA
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 25V, Positive (Annotated)splash10-000f-9300000000-1bc18b05388cd2213573View in MoNA
LC-MS/MSLC-MS/MS Spectrum - Quattro_QQQ 40V, Positive (Annotated)splash10-01p9-9000000000-4483af567feecb34a651View in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Positivesplash10-03gl-0907000000-a1de7813fbe8b5258c10View in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Positivesplash10-03e9-0900000000-79cc5059a3f338e8c1ddView in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Positivesplash10-03di-3900000000-851d0bc84d91b6e09579View in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Negativesplash10-002f-0749000000-af1d18f2bc3ab8e02883View in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Negativesplash10-0200-2902000000-67218697344afb9e70faView in MoNA
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Negativesplash10-01td-4900000000-40aa2d8125769803cfbbView in MoNA
1D NMR1H NMR SpectrumNot AvailableView in JSpectraViewer
1D NMR13C NMR SpectrumNot AvailableView in JSpectraViewer
2D NMR[1H,1H] 2D NMR SpectrumNot AvailableView in JSpectraViewer
2D NMR[1H,13C] 2D NMR SpectrumNot AvailableView in JSpectraViewer
Biological Properties
Cellular Locations
  • Cytoplasm
  • Extracellular
  • Lysosome
  • Golgi apparatus
Biofluid Locations
  • Blood
  • Breast Milk
  • Feces
  • Urine
Tissue Location
  • Bladder
  • Gut
  • Intestine
  • Muscle
  • Platelet
  • Skin
  • Spleen
Pathways
NameSMPDB/PathwhizKEGG
Congenital disorder of glycosylation CDG-IIdPw000555Pw000555 greyscalePw000555 simpleNot Available
GLUT-1 deficiency syndromePw000556Pw000556 greyscalePw000556 simpleNot Available
Galactose MetabolismPw000159Pw000159 greyscalePw000159 simpleMap00052
GalactosemiaPw000200Pw000200 greyscalePw000200 simpleNot Available
Lactose DegradationPw000153Pw000153 greyscalePw000153 simpleNot Available
Normal Concentrations
BiofluidStatusValueAgeSexConditionReferenceDetails
BloodExpected but not Quantified Not AvailableNot Available
Normal
    details
    Breast MilkDetected and Quantified170000 +/- 7300 uMAdult (>18 years old)Female
    Normal
    details
    FecesDetected but not Quantified Infant (0-1 year old)Both
    Normal
    details
    UrineDetected and Quantified19.378 +/- 10.997 umol/mmol creatinineChildren (1 - 13 years old)Not Specified
    Normal
      • Mordechai, Hien, ...
    details
    UrineDetected and Quantified11.8 (1.0-24.2) umol/mmol creatinineAdult (>18 years old)Both
    Normal
    details
    UrineDetected and Quantified30.0 (13.0-49.0) umol/mmol creatinineInfant (0-1 year old)BothNormal
      • Geigy Scientific ...
    details
    UrineDetected and Quantified1.45 (0.63-3.45) umol/mmol creatinineAdult (>18 years old)BothNormal
      • Geigy Scientific ...
    details
    UrineDetected and Quantified36.31 +/- 6.60 umol/mmol creatinineAdult (>18 years old)Not Specified
    Normal
    details
    UrineDetected and Quantified66.02 +/- 6.60 umol/mmol creatinineAdult (>18 years old)Not Specified
    Normal
    details
    UrineDetected and Quantified676.75 +/- 85.83 umol/mmol creatinineNewborn (0-30 days old)Not Specified
    Normal
    details
    UrineDetected and Quantified6.08 +/- 6.07 umol/mmol creatinineInfant (0-1 year old)BothNormal details
    Abnormal Concentrations
    BiofluidStatusValueAgeSexConditionReferenceDetails
    UrineDetected and Quantified51.475 +/- 126.985 umol/mmol creatinineChildren (1 - 13 years old)Not Specified
    Eosinophilic esophagitis
      • Mordechai, Hien, ...
    details
    Associated Disorders and Diseases
    Disease ReferencesNone
    Associated OMIM IDsNone
    DrugBank IDDB04465
    DrugBank Metabolite IDNot Available
    Phenol Explorer Compound IDNot Available
    Phenol Explorer Metabolite IDNot Available
    FoodDB IDFDB001145
    KNApSAcK IDC00001136
    Chemspider ID76293
    KEGG Compound IDC00243
    BioCyc IDLACTOSE
    BiGG ID34366
    Wikipedia LinkLactose
    METLIN ID267
    PubChem Compound84571
    PDB IDLBT
    ChEBI ID36219
    References
    Synthesis ReferenceRuffing, Anne; Mao, Zichao; Ruizhen Chen, Rachel. Metabolic engineering of Agrobacterium sp. for UDP-galactose regeneration and oligosaccharide synthesis. Metabolic Engineering (2006), 8(5), 465-473.
    Material Safety Data Sheet (MSDS)Download (PDF)
    General References
    1. Jung SK, Fujimoto D: A novel beta-galactoside-binding lectin in adult rat kidney. J Biochem. 1994 Sep;116(3):547-53. [PubMed:7852273 ]
    2. Oozeer R, Furet JP, Goupil-Feuillerat N, Anba J, Mengaud J, Corthier G: Differential activities of four Lactobacillus casei promoters during bacterial transit through the gastrointestinal tracts of human-microbiota-associated mice. Appl Environ Microbiol. 2005 Mar;71(3):1356-63. [PubMed:15746338 ]
    3. Dimopoulos MA, Anagnostopoulos A: Thalidomide in relapsed/refractory multiple myeloma: pivotal trials conducted outside the United States. Semin Hematol. 2003 Oct;40(4 Suppl 4):8-16. [PubMed:15015891 ]
    4. Muthusamy A, Erickson DR, Sheykhnazari M, Bhavanandan VP: Enhanced binding of modified pentosan polysulfate and heparin to bladder--a strategy for improved treatment of interstitial cystitis. Urology. 2006 Jan;67(1):209-13. [PubMed:16413377 ]
    5. Johnson JD, Simoons FJ, Hurwitz R, Grange A, Mitchell CH, Sinatra FR, Sunshine P, Robertson WV, Bennett PH, Kretchmer N: Lactose malabsorption among the Pima indians of Arizona. Gastroenterology. 1977 Dec;73(6):1299-304. [PubMed:578795 ]
    6. Lustenberger RW: [A 23-year old patient with chronic diarrhea. Celiac disease and lactose intolerance]. Praxis (Bern 1994). 2005 Feb 2;94(5):163-4. [PubMed:15745382 ]
    7. Sharma A, DiCioccio RA, Allen HJ: Identification and synthesis of a novel 15 kDa beta-galactoside-binding lectin in human leukocytes. Glycobiology. 1992 Aug;2(4):285-92. [PubMed:1421750 ]
    8. Rana SV, Bhasin DK, Vinayak VK: Lactose hydrogen breath test in Giardia lamblia-positive patients. Dig Dis Sci. 2005 Feb;50(2):259-61. [PubMed:15745082 ]
    9. Mitchell JD, Brand J, Halbisch J: Weight-gain inhibition by lactose in Australian Aboriginal children. A controlled trial of normal and lactose hydrolysed milk. Lancet. 1977 Mar 5;1(8010):500-2. [PubMed:65606 ]
    10. Soupene E, van Heeswijk WC, Plumbridge J, Stewart V, Bertenthal D, Lee H, Prasad G, Paliy O, Charernnoppakul P, Kustu S: Physiological studies of Escherichia coli strain MG1655: growth defects and apparent cross-regulation of gene expression. J Bacteriol. 2003 Sep;185(18):5611-26. [PubMed:12949114 ]
    11. Yeoh E, Horowitz M, Russo A, Muecke T, Robb T, Chatterton B: The effects of abdominal irradiation for seminoma of the testis on gastrointestinal function. J Gastroenterol Hepatol. 1995 Mar-Apr;10(2):125-30. [PubMed:7787155 ]
    12. Bondesson E, Bengtsson T, Borgstrom L, Nilsson LE, Norrgren K, Olsson B, Svensson M, Wollmer P: Dose delivery late in the breath can increase dry powder aerosol penetration into the lungs. J Aerosol Med. 2005 Spring;18(1):23-33. [PubMed:15741771 ]
    13. Roberson CM: Lactose intolerance. Ala Nurse. 2004 Dec-2005 Feb;31(4):23-4; quiz 24. [PubMed:15662762 ]
    14. Kim KI, Lee WS, Benevenga NJ: Feeding diets containing high levels of milk products or cellulose decrease urease activity and ammonia production in rat intestine. J Nutr. 1998 Jul;128(7):1186-91. [PubMed:9649604 ]
    15. Gunther S, Patterson RE, Kristal AR, Stratton KL, White E: Demographic and health-related correlates of herbal and specialty supplement use. J Am Diet Assoc. 2004 Jan;104(1):27-34. [PubMed:14702580 ]
    16. Delaveau P: [Milk lactose. Hypothesis on its biological importance]. Ann Pharm Fr. 2003;61(5):340-2. [PubMed:13130292 ]
    17. Vilotte JL: Lowering the milk lactose content in vivo: potential interests, strategies and physiological consequences. Reprod Nutr Dev. 2002 Mar-Apr;42(2):127-32. [PubMed:12216958 ]
    18. Szilagyi A: Review article: lactose--a potential prebiotic. Aliment Pharmacol Ther. 2002 Sep;16(9):1591-602. [PubMed:12197838 ]
    19. Swagerty DL Jr, Walling AD, Klein RM: Lactose intolerance. Am Fam Physician. 2002 May 1;65(9):1845-50. [PubMed:12018807 ]

    Enzymes

    General function:
    Involved in hydrolase activity, hydrolyzing O-glycosyl compounds
    Specific function:
    LPH splits lactose in the small intestine.
    Gene Name:
    LCT
    Uniprot ID:
    P09848
    Molecular weight:
    218584.77
    General function:
    Involved in transferase activity, transferring glycosyl groups
    Specific function:
    Responsible for the synthesis of complex-type N-linked oligosaccharides in many glycoproteins as well as the carbohydrate moieties of glycolipids. Can produce lactose.
    Gene Name:
    B4GALT2
    Uniprot ID:
    O60909
    Molecular weight:
    41971.815
    General function:
    Involved in lactose synthase activity
    Specific function:
    Regulatory subunit of lactose synthase, changes the substrate specificity of galactosyltransferase in the mammary gland making glucose a good acceptor substrate for this enzyme. This enables LS to synthesize lactose, the major carbohydrate component of milk. In other tissues, galactosyltransferase transfers galactose onto the N-acetylglucosamine of the oligosaccharide chains in glycoproteins.
    Gene Name:
    LALBA
    Uniprot ID:
    P00709
    Molecular weight:
    Not Available
    General function:
    Involved in transferase activity, transferring glycosyl groups
    Specific function:
    The Golgi complex form catalyzes the production of lactose in the lactating mammary gland and could also be responsible for the synthesis of complex-type N-linked oligosaccharides in many glycoproteins as well as the carbohydrate moieties of glycolipids. The cell surface form functions as a recognition molecule during a variety of cell to cell and cell to matrix interactions, as those occurring during development and egg fertilization, by binding to specific oligosaccharide ligands on opposing cells or in the extracellular matrix.
    Gene Name:
    B4GALT1
    Uniprot ID:
    P15291
    Molecular weight:
    43919.895
    General function:
    Involved in hydrolase activity, hydrolyzing O-glycosyl compounds
    Specific function:
    Cleaves beta-linked terminal galactosyl residues from gangliosides, glycoproteins, and glycosaminoglycans. Isoform 2 has no beta-galactosidase catalytic activity, but plays functional roles in the formation of extracellular elastic fibers (elastogenesis) and in the development of connective tissue. Seems to be identical to the elastin-binding protein (EBP), a major component of the non-integrin cell surface receptor expressed on fibroblasts, smooth muscle cells, chondroblasts, leukocytes, and certain cancer cell types. In elastin producing cells, associates with tropoelastin intracellularly and functions as a recycling molecular chaperone which facilitates the secretions of tropoelastin and its assembly into elastic fibers.
    Gene Name:
    GLB1
    Uniprot ID:
    P16278
    Molecular weight:
    Not Available
    General function:
    Involved in glycolipid transporter activity
    Specific function:
    Accelerates the intermembrane transfer of various glycolipids. Catalyzes the transfer of various glycosphingolipids between membranes but does not catalyze the transfer of phospholipids. May be involved in the intracellular translocation of glucosylceramides
    Gene Name:
    GLTP
    Uniprot ID:
    Q9NZD2
    Molecular weight:
    23849.6
    References
    1. Overington JP, Al-Lazikani B, Hopkins AL: How many drug targets are there? Nat Rev Drug Discov. 2006 Dec;5(12):993-6. [PubMed:17139284 ]
    2. Imming P, Sinning C, Meyer A: Drugs, their targets and the nature and number of drug targets. Nat Rev Drug Discov. 2006 Oct;5(10):821-34. [PubMed:17016423 ]