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Record Information
Creation Date2005-11-16 15:48:42 UTC
Update Date2015-03-09 22:57:11 UTC
Secondary Accession NumbersNone
Metabolite Identification
Common NameKeratan
DescriptionKeratan is a sulfated mucopolysaccharide initially isolated from bovine cornea. At least two types are known. Type I, found mostly in the cornea, contains D-galactose and D-glucosamine-6-O-sulfate as the repeating unit; type II, found in skeletal tissues, contains D-galactose and D-galactosamine-6-O-sulfate as the repeating unit.
  1. Keratan 6'-sulfate
  2. Keratan 6'-sulphate
  3. Keratan sulfate
  4. Keratan sulphate
  5. Kerato 6'-sulfate
  6. Kerato 6'-sulphate
  7. Kerato sulfate
  8. Kerato sulphate
Chemical FormulaC28H48N2O32S4
Average Molecular Weight1052.935
Monoisotopic Molecular Weight1052.10730021
IUPAC Name{[(2S,4S,5R,6S)-5-acetamido-6-{[(2S,3R,4S,5S,6R)-2-{[(2R,3S,4R,5R,6S)-5-acetamido-4-hydroxy-2-[(sulfooxy)methyl]-6-{[(2R,3R,4S,5S,6R)-2,3,5-trihydroxy-6-[(sulfooxy)methyl]oxan-4-yl]oxy}oxan-3-yl]oxy}-3,5-dihydroxy-6-[(sulfooxy)methyl]oxan-4-yl]oxy}-4-hydroxyoxan-2-yl]methoxy}sulfonic acid
Traditional Name[(2S,4S,5R,6S)-5-acetamido-6-{[(2S,3R,4S,5S,6R)-2-{[(2R,3S,4R,5R,6S)-5-acetamido-4-hydroxy-2-[(sulfooxy)methyl]-6-{[(2R,3R,4S,5S,6R)-2,3,5-trihydroxy-6-[(sulfooxy)methyl]oxan-4-yl]oxy}oxan-3-yl]oxy}-3,5-dihydroxy-6-[(sulfooxy)methyl]oxan-4-yl]oxy}-4-hydroxyoxan-2-yl]methoxysulfonic acid
CAS Registry Number69992-87-6
InChI Identifier
Chemical Taxonomy
DescriptionThis compound belongs to the class of organic compounds known as oligosaccharide sulfates. These are carbohydrates containing between 3 and 9 sugar units, one of which bear one or more sulfate groups.
KingdomOrganic compounds
Super ClassOrganooxygen compounds
ClassCarbohydrates and carbohydrate conjugates
Sub ClassOligosaccharides
Direct ParentOligosaccharide sulfates
Alternative Parents
  • Oligosaccharide sulfate
  • N-acyl-alpha-hexosamine
  • Glucosamine
  • O-glycosyl compound
  • Glycosyl compound
  • Amino saccharide
  • Sulfuric acid monoester
  • Sulfuric acid ester
  • Alkyl sulfate
  • Sulfate-ester
  • Oxane
  • Acetamide
  • Organic sulfuric acid or derivatives
  • Secondary carboxylic acid amide
  • Secondary alcohol
  • Polyol
  • Hemiacetal
  • Carboxamide group
  • Oxacycle
  • Organoheterocyclic compound
  • Carboxylic acid derivative
  • Carboxylic acid amide
  • Acetal
  • Hydrocarbon derivative
  • Organonitrogen compound
  • Carbonyl group
  • Alcohol
  • Aliphatic heteromonocyclic compound
Molecular FrameworkAliphatic heteromonocyclic compounds
External DescriptorsNot Available
StatusDetected and Quantified
  • Endogenous
BiofunctionNot Available
ApplicationNot Available
Cellular locationsNot Available
Physical Properties
Experimental Properties
Melting PointNot AvailableNot Available
Boiling PointNot AvailableNot Available
Water SolubilityNot AvailableNot Available
LogPNot AvailableNot Available
Predicted Properties
Water Solubility24.9 mg/mLALOGPS
pKa (Strongest Acidic)-2.6ChemAxon
pKa (Strongest Basic)-4ChemAxon
Physiological Charge-4ChemAxon
Hydrogen Acceptor Count28ChemAxon
Hydrogen Donor Count13ChemAxon
Polar Surface Area518.82 Å2ChemAxon
Rotatable Bond Count20ChemAxon
Refractivity194.24 m3·mol-1ChemAxon
Polarizability92.22 Å3ChemAxon
Number of Rings4ChemAxon
Rule of FiveYesChemAxon
Ghose FilterYesChemAxon
Veber's RuleYesChemAxon
MDDR-like RuleYesChemAxon
SpectraNot Available
Biological Properties
Cellular LocationsNot Available
Biofluid Locations
  • Blood
Tissue Location
  • Cartilage
  • Epidermis
  • Fibroblasts
  • Intestine
  • Prostate
PathwaysNot Available
Normal Concentrations
BloodDetected and Quantified0.14 (0.01-0.30) uMAdult (>18 years old)BothNormal details
Abnormal Concentrations
BloodDetected and Quantified0.75 (0.10-1.44) uMAdult (>18 years old)BothMucopolysaccharidosis IVA details
Associated Disorders and Diseases
Disease References
Mucopolysaccharidosis IVA
  1. Tomatsu S, Okamura K, Taketani T, Orii KO, Nishioka T, Gutierrez MA, Velez-Castrillon S, Fachel AA, Grubb JH, Cooper A, Thornley M, Wraith E, Barrera LA, Giugliani R, Schwartz IV, Frenking GS, Beck M, Kircher SG, Paschke E, Yamaguchi S, Ullrich K, Isogai K, Suzuki Y, Orii T, Kondo N, Creer M, Noguchi A: Development and testing of new screening method for keratan sulfate in mucopolysaccharidosis IVA. Pediatr Res. 2004 Apr;55(4):592-7. Epub 2004 Jan 7. [14711889 ]
Associated OMIM IDs
  • 253000 (Mucopolysaccharidosis IVA )
DrugBank IDNot Available
DrugBank Metabolite IDNot Available
Phenol Explorer Compound IDNot Available
Phenol Explorer Metabolite IDNot Available
FoodDB IDFDB022459
KNApSAcK IDNot Available
Chemspider ID394000
KEGG Compound IDC00573
BiGG IDNot Available
Wikipedia Linkkeratan sulfate
NuGOwiki LinkHMDB01165
Metagene LinkHMDB01165
METLIN IDNot Available
PubChem Compound446715
PDB IDNot Available
ChEBI IDNot Available
Synthesis ReferenceNot Available
Material Safety Data Sheet (MSDS)Not Available
General References
  1. Isnard N, Fodil-Bourahla I, Robert AM, Robert L: Pharmacology of skin aging. Stimulation of glycosaminoglycan biosynthesis by L-fucose and fucose-rich polysaccharides, effect of in vitro aging of fibroblasts. Biomed Pharmacother. 2004 Apr;58(3):202-4. [15082343 ]
  2. Willen MD, Sorrell JM, Lekan CC, Davis BR, Caplan AI: Patterns of glycosaminoglycan/proteoglycan immunostaining in human skin during aging. J Invest Dermatol. 1991 Jun;96(6):968-74. [1710640 ]
  3. Brunnee T, Reddigari SR, Shibayama Y, Kaplan AP, Silverberg M: Mast cell derived heparin activates the contact system: a link to kinin generation in allergic reactions. Clin Exp Allergy. 1997 Jun;27(6):653-63. [9208186 ]
  4. Block JA, Schnitzer TJ, Andersson GB, Lenz ME, Jeffery R, McNeill TW, Thonar EJ: The effect of chemonucleolysis on serum keratan sulfate levels in humans. Arthritis Rheum. 1989 Jan;32(1):100-4. [2521451 ]
  5. Thonar EJ, Lenz ME, Klintworth GK, Caterson B, Pachman LM, Glickman P, Katz R, Huff J, Kuettner KE: Quantification of keratan sulfate in blood as a marker of cartilage catabolism. Arthritis Rheum. 1985 Dec;28(12):1367-76. [2935158 ]
  6. Sorrell JM, Caterson B: Detection of age-related changes in the distributions of keratan sulfates and chondroitin sulfates in developing chick limbs: an immunocytochemical study. Development. 1989 Aug;106(4):657-63. [2562661 ]
  7. Thonar EJ, Schnitzer TJ, Kuettner KE: Quantification of keratan sulfate in blood as a marker of cartilage catabolism. J Rheumatol. 1987 May;14 Spec No:23-4. [2957502 ]
  8. al-Hakim A, Linhardt RJ: Electrophoresis and detection of nanogram quantities of exogenous and endogenous glycosaminoglycans in biological fluids. Appl Theor Electrophor. 1991;1(6):305-12. [1718441 ]
  9. Kliner DJ, Gorski JP, Thonar EJ: Keratan sulfate levels in sera of patients bearing cartilage tumors. Cancer. 1987 Jun 1;59(11):1931-5. [2952259 ]
  10. Bautch JC, Malone DG, Vailas AC: Effects of exercise on knee joints with osteoarthritis: a pilot study of biologic markers. Arthritis Care Res. 1997 Feb;10(1):48-55. [9313390 ]
  11. Morocutti M, Marchini M, Colombo B, Ruggeri A: Heterogeneity of proteoglycan particles in thin sections and replicas of human articular cartilage. Acta Biol Hung. 1984;35(2-4):233-43. [6242453 ]
  12. Cameron M, Buchgraber A, Passler H, Vogt M, Thonar E, Fu F, Evans CH: The natural history of the anterior cruciate ligament-deficient knee. Changes in synovial fluid cytokine and keratan sulfate concentrations. Am J Sports Med. 1997 Nov-Dec;25(6):751-4. [9397261 ]
  13. Klintworth GK, Meyer R, Dennis R, Hewitt AT, Stock EL, Lenz ME, Hassell JR, Stark WJ Jr, Kuettner KE, Thonar EJ: Macular corneal dystrophy. Lack of keratan sulfate in serum and cornea. Ophthalmic Paediatr Genet. 1986 Dec;7(3):139-43. [2951638 ]
  14. Israel HA, Diamond BE, Saed-Nejad F, Ratcliffe A: Correlation between arthroscopic diagnosis of osteoarthritis and synovitis of the human temporomandibular joint and keratan sulfate levels in the synovial fluid. J Oral Maxillofac Surg. 1997 Mar;55(3):210-7; discussion 217-8. [9054908 ]
  15. Plaas AH, West LA, Thonar EJ, Karcioglu ZA, Smith CJ, Klintworth GK, Hascall VC: Altered fine structures of corneal and skeletal keratan sulfate and chondroitin/dermatan sulfate in macular corneal dystrophy. J Biol Chem. 2001 Oct 26;276(43):39788-96. Epub 2001 Aug 20. [11514545 ]
  16. Thonar EJ, Glant T: Serum keratan sulfate--a marker of predisposition to polyarticular osteoarthritis. Clin Biochem. 1992 Jun;25(3):175-80. [1633632 ]
  17. Thonar EJ: Serum keratan sulfate concentration as a measure of the catabolism of cartilage proteoglycans. Ryumachi. 1990 Dec;30(6):461-8. [2100374 ]
  18. Holland JW, Meehan KL, Redmond SL, Dawkins HJ: Purification of the keratan sulfate proteoglycan expressed in prostatic secretory cells and its identification as lumican. Prostate. 2004 May 15;59(3):252-9. [15042600 ]
  19. Israel HA, Saed-Nejad F, Ratcliffe A: Early diagnosis of osteoarthrosis of the temporomandibular joint: correlation between arthroscopic diagnosis and keratan sulfate levels in the synovial fluid. J Oral Maxillofac Surg. 1991 Jul;49(7):708-11; discussion 712. [2056369 ]


General function:
Involved in sulfotransferase activity
Specific function:
Sulfotransferase that utilizes 3'-phospho-5'-adenylyl sulfate (PAPS) as sulfonate donor to catalyze the transfer of sulfate to position 6 of the N-acetylgalactosamine (GalNAc) residue of chondroitin. Chondroitin sulfate constitutes the predominant proteoglycan present in cartilage and is distributed on the surfaces of many cells and extracellular matrices. Can also sulfate Gal residues of keratan sulfate, another glycosaminoglycan, and the Gal residues in sialyl N-acetyllactosamine (sialyl LacNAc) oligosaccharides. May play a role in the maintenance of naive T-lymphocytes in the spleen.
Gene Name:
Uniprot ID:
Molecular weight:
General function:
Involved in sulfotransferase activity
Specific function:
Sulfotransferase that utilizes 3'-phospho-5'-adenylyl sulfate (PAPS) as sulfonate donor to catalyze the transfer of sulfate to position 6 of galactose (Gal) residues of keratan. Has a preference for sulfating keratan sulfate, but it also transfers sulfate to the unsulfated polymer. The sulfotransferase activity on sialyl LacNAc structures is much higher than the corresponding desialylated substrate, and only internal Gal residues are sulfated. May function in the sulfation of sialyl N-acetyllactosamine oligosaccharide chains attached to glycoproteins. Participates in biosynthesis of selectin ligands. Selectin ligands are present in high endothelial cells (HEVs) and play a central role in lymphocyte homing at sites of inflammation.
Gene Name:
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Molecular weight:
Phosphoadenosine phosphosulfate + Keratan → Adenosine 3',5'-diphosphate + Keratandetails
General function:
Involved in sulfotransferase activity
Specific function:
Sulfotransferase that utilizes 3'-phospho-5'-adenylyl sulfate (PAPS) as sulfonate donor to catalyze the transfer of sulfate to position 6 of non-reducing N-acetylglucosamine (GlcNAc) residues. Preferentially acts on mannose-linked GlcNAc. Also able to catalyze the transfer of sulfate to position 6 of the N-acetylgalactosamine (GalNAc) residue of chondroitin. Also acts on core 2 mucin-type oligosaccharide and N-acetyllactosamine oligomer with a lower efficiency. Has weak or no activity toward keratan sulfate and oligosaccharides containing the Galbeta1-4GlcNAc. Catalyzes 6-O-sulfation of beta-benzyl GlcNAc but not alpha- or beta-benzyl GalNAc.
Gene Name:
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Molecular weight:
General function:
Involved in hydrolase activity, hydrolyzing O-glycosyl compounds
Specific function:
Plays an important role in the degradation of dermatan and keratan sulfates.
Gene Name:
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Molecular weight:
General function:
Involved in catalytic activity
Specific function:
Not Available
Gene Name:
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Molecular weight:
Not Available
General function:
Involved in catalytic activity
Specific function:
Not Available
Gene Name:
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Molecular weight:
Not Available
General function:
Involved in protein binding
Specific function:
May be important in developing and maintaining corneal transparency and for the structure of the stromal matrix
Gene Name:
Uniprot ID:
Molecular weight:
General function:
Involved in protein binding
Specific function:
Affects the rate of fibrils formation. May have a primary role in collagen fibrillogenesis
Gene Name:
Uniprot ID:
Molecular weight:
General function:
Involved in sulfotransferase activity
Specific function:
Catalyzes the transfer of sulfate to position 6 of non- reducing N-acetylglucosamine (GlcNAc) residues of keratan. Mediates sulfation of keratan in cornea. Keratan sulfate plays a central role in maintaining corneal transparency. Acts on the non- reducing terminal GlcNAc of short and long carbohydrate substrates that have poly-N-acetyllactosamine structures
Gene Name:
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Molecular weight:
General function:
Involved in galactosyltransferase activity
Specific function:
May be involved in keratane sulfate biosynthesis. Transfers N-acetylgalactosamine on to keratan sulfate-related glycans. May play a role in preventing cells from migrating out of the original tissues and invading surrounding tissues
Gene Name:
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General function:
Involved in protein binding
Specific function:
May be implicated in biomineralization processes. Has a function in binding of osteoblasts via the alpha(V)beta(3)- integrin
Gene Name:
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General function:
Involved in female pregnancy
Specific function:
Not Available
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