1.0 2011-09-21 00:23:47 UTC 2015-07-21 06:57:29 UTC FDB023047 Iduronic acid Iduronic acid is a constituent of glycosaminoglycans heparin and heparan sulfate in varying proportions providing considerable diversity in sequence and biological function. The glycosaminoglycans (GAGs) are linear polysaccharides with alternating uronic acids (Iduronic acid and Glucuronic acid) and hexosamine residues, in which a limited set of monosaccharide units gives rise to a number of complex sequences by variable substitution with O-sulfate, N-sulfate, and N-acetyl groups. GAGs usually exist as the O-linked side-chains of proteoglycans, displaying a set of physiological functions which is remarkably wide and as yet incompletely explored. They may act as structural components of connective tissue and the extracellular matrix, or as specific ligands in the relationship between the cell surface and its surroundings. Heparan sulfate exists on the surface of most or all mammalian cells and can display a remarkable range of different sequence motifs; its range of interactions and possible functions reflect its structural complexity. The main repeat unit of heparin structurally resembles the protein binding sequences in heparan sulfate, but contains a higher percentage of sulfated residues. Utilized therapeutically as an anticoagulant and readily available in good quantities heparin serves as a useful model for heparan sulfate. Theoretical and experimental studies indicate that L-Iduronic acid residues of glycosaminoglycans are in equilibrium of different conformations, the relative proportion of conformers being a function of sulfation pattern and sequence. This unique conformational flexibility may provide an explanation for the stronger binding and associated higher biological activities of Iduronic acid-containing glycosaminoglycans (such as heparin, heparan sulfate and dermatan sulfate) as compared with other GAGs having similar charge density but with the more rigid glucuronic acid as the major uronic acid residue. Dermatan sulfates and heparins, which contain L-Iduronic acid in their backbone, show higher low-density lipoprotein (LDL)-affinity than chondroitin sulfates, which contain only D-glucuronic acid. Though confirming a non-specific, predominantly electrostatic interaction between GAGs and LDL, these results indicate modulation of LDL affinity by the polysaccharide backbone. Naturally oversulfated dermatan sulfate (SO3H/COOH ca. 1.2), mainly oversulfated at C-2 of Iduronic acid residues, show comparatively higher anticoagulant activity. (PMID: 3076283, 8466951, 8542607, 11087707) [HMDB] iduronate L-Iduronate L-Iduronic acid C6H10O7 194.1394 194.042652674 (2S,3R,4R,5S)-2,3,4,5-tetrahydroxy-6-oxohexanoic acid iduronic acid 3402-98-0 O[C@H](C=O)[C@H](O)[C@@H](O)[C@H](O)C(O)=O InChI=1S/C6H10O7/c7-1-2(8)3(9)4(10)5(11)6(12)13/h1-5,8-11H,(H,12,13)/t2-,3+,4-,5+/m1/s1 IAJILQKETJEXLJ-LECHCGJUSA-N belongs to the class of organic compounds known as glucuronic acid derivatives. Glucuronic acid derivatives are compounds containing a glucuronic acid moiety (or a derivative), which consists of a glucose moiety with the C6 carbon oxidized to a carboxylic acid. Glucuronic acid derivatives Organic compounds Organic oxygen compounds Organooxygen compounds Carbohydrates and carbohydrate conjugates Aliphatic acyclic compounds Alpha hydroxy acids and derivatives Alpha-hydroxyaldehydes Beta hydroxy acids and derivatives Beta-hydroxy aldehydes Carboxylic acids Hexoses Hydrocarbon derivatives Hydroxy fatty acids Medium-chain fatty acids Medium-chain hydroxy acids and derivatives Monocarboxylic acids and derivatives Organic oxides Polyols Secondary alcohols Alcohol Aldehyde Aliphatic acyclic compound Alpha-hydroxy acid Alpha-hydroxyaldehyde Beta-hydroxy acid Beta-hydroxy aldehyde Carbonyl group Carboxylic acid Carboxylic acid derivative Fatty acid Fatty acyl Glucuronic acid or derivatives Hexose monosaccharide Hydrocarbon derivative Hydroxy acid Hydroxy fatty acid Medium-chain fatty acid Medium-chain hydroxy acid Monocarboxylic acid or derivatives Monosaccharide Organic oxide Polyol Secondary alcohol Solid logp -2.32 ALOGPS logs -0.29 ALOGPS solubility 1.00e+02 g/l ALOGPS logp -3.2 ChemAxon pka_strongest_acidic 3.24 ChemAxon pka_strongest_basic -3.7 ChemAxon iupac (2S,3R,4R,5S)-2,3,4,5-tetrahydroxy-6-oxohexanoic acid ChemAxon average_mass 194.1394 ChemAxon mono_mass 194.042652674 ChemAxon smiles O[C@H](C=O)[C@H](O)[C@@H](O)[C@H](O)C(O)=O ChemAxon formula C6H10O7 ChemAxon inchi InChI=1S/C6H10O7/c7-1-2(8)3(9)4(10)5(11)6(12)13/h1-5,8-11H,(H,12,13)/t2-,3+,4-,5+/m1/s1 ChemAxon inchikey IAJILQKETJEXLJ-LECHCGJUSA-N ChemAxon polar_surface_area 135.29 ChemAxon refractivity 37.21 ChemAxon polarizability 16.1 ChemAxon rotatable_bond_count 5 ChemAxon acceptor_count 7 ChemAxon donor_count 5 ChemAxon physiological_charge -1 ChemAxon formal_charge 0 ChemAxon Specdb::MsIr 1814 Specdb::MsIr 1815 Specdb::MsIr 1816 Specdb::CMs 11142 Specdb::CMs 38462 Specdb::CMs 169559 Specdb::MsMs 75312 Specdb::MsMs 75313 Specdb::MsMs 75314 Specdb::MsMs 134931 Specdb::MsMs 134932 Specdb::MsMs 134933 Specdb::MsMs 2660113 Specdb::MsMs 2660114 Specdb::MsMs 2660115 Specdb::MsMs 3018474 Specdb::MsMs 3018475 Specdb::MsMs 3018476 Specdb::NmrOneD 122818 Specdb::NmrOneD 122819 Specdb::NmrOneD 122820 Specdb::NmrOneD 122821 Specdb::NmrOneD 122822 Specdb::NmrOneD 122823 Specdb::NmrOneD 122824 Specdb::NmrOneD 122825 Specdb::NmrOneD 122826 Specdb::NmrOneD 122827 Specdb::NmrOneD 122828 Specdb::NmrOneD 122829 Specdb::NmrOneD 122830 Specdb::NmrOneD 122831 Specdb::NmrOneD 122832 Specdb::NmrOneD 122833 Specdb::NmrOneD 122834 Specdb::NmrOneD 122835 Specdb::NmrOneD 122836 Specdb::NmrOneD 122837 HMDB02704 24769 #<Reference:0x000055ce32232d90> #<Reference:0x000055ce32232bb0> #<Reference:0x000055ce322329a8> #<Reference:0x000055ce32232750> #<Reference:0x000055ce32232548> #<Reference:0x000055ce32232318> #<Reference:0x000055ce32232110> #<Reference:0x000055ce32231ee0> Anatidae Type 1 specific Anatidae 8830 Beefalo Type 1 specific Bos taurus X Bison bison 297284 Bison Type 1 specific Bison bison 9901 Buffalo Type 1 specific Bubalus bubalis 89462 Cattle (Beef, Veal) Type 1 specific Bos taurus 9913 Chicken Type 1 specific Gallus gallus 9031 Columbidae (Dove, Pigeon) Type 1 specific Columbidae 8930 Deer Type 1 specific Cervidae 9850 Domestic goat Type 1 specific Capra aegagrus hircus 9925 Domestic pig Type 1 specific Sus scrofa domestica 9825 Elk Type 1 specific Cervus canadensis 1574408 Emu Type 1 specific Dromaius novaehollandiae 8790 European rabbit Type 1 specific Oryctolagus 9984 Greylag goose Type 1 specific Anser anser 8843 Guinea hen Type 1 specific Numida meleagris 8996 Horse Type 1 specific Equus caballus 9796 Mallard duck Type 1 specific Anas platyrhynchos 8839 Mountain hare Type 1 specific Lepus timidus 62621 Mule deer Type 1 specific Odocoileus 9871 Ostrich Type 1 specific Struthio camelus 8801 Pheasant Type 1 specific Phasianus colchicus 9054 Quail Type 1 specific Phasianidae 9005 Rabbit Type 1 specific Leporidae 9979 Rock ptarmigan Type 1 specific Lagopus muta 64668 Sheep (Mutton, Lamb) Type 1 specific Ovis aries 9940 Squab Type 1 specific Columba 8931 Turkey Type 1 specific Meleagris gallopavo 9103 Velvet duck Type 1 specific Melanitta fusca 371864 Wild boar Type 1 specific Sus scrofa 9823 Alpha-L-iduronidase P35475 IDUA Carbohydrate sulfotransferase 14 Q8NCH0 CHST14 Dermatan-sulfate epimerase Q9UL01 DSE Heparan sulfate glucosamine 3-O-sulfotransferase 2 Q9Y278 HS3ST2 Heparan sulfate glucosamine 3-O-sulfotransferase 3A1 Q9Y663 HS3ST3A1 Heparan sulfate glucosamine 3-O-sulfotransferase 3B1 Q9Y662 HS3ST3B1 Heparan sulfate glucosamine 3-O-sulfotransferase 4 Q9Y661 HS3ST4 UDP-glucuronosyltransferase 1-1 P22309 UGT1A1 UDP-glucuronosyltransferase 1-4 P22310 UGT1A4 UDP-glucuronosyltransferase 1-6 P19224 UGT1A6 UDP-glucuronosyltransferase 1-9 O60656 UGT1A9 UDP-glucuronosyltransferase 2B4 P06133 UGT2B4 UDP-glucuronosyltransferase 2B7 P16662 UGT2B7