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Journal articles on the topic 'Sulfato complex'

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Published: 4 June 2021
Last updated: 1 February 2022

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1

Wieghardt, Karl, Stefan Drüeke, Phalguni Chaudhuri, Ulrich Flörke, Hans-Jürgen Haupt, Bernhard Nuber, and Johannes Weiss. "Bioanorganische Modellkomplexe für Metalloproteine des Eisen(III): Synthese, Kristallstrukturen und Magnetismus der zweikernigen Komplexe [L2Fe2III(µ-O)(μ-SO4)2] · 3 H2O und [L2Fe2III(μ-O)(μ-SO3)2] · 5/3 NaClO4 · (H2O)3.67 (L = N,N′N″-Trimethyl-1,4,7-triazacyclononan) / Bioinorganic Model Complexes for Metalloproteins of Iron(III): Syntheses, Crystal Structures, and Magnetism of the Binuclear Complexes [L2Fe2III(μ-O)(μ-SO4)2]·3 Η2O and [L2Fe2III(μ-O)(μ-SO3)2] · 5/3 NaClO4 · (H2O)3.67 (L = N,N′,N″-Trimethyl-1,4,7-triazacyclononane)." Zeitschrift für Naturforschung B 44, no. 9 (September 1, 1989): 1093–101. http://dx.doi.org/10.1515/znb-1989-0916.

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The reaction of LFeCl3 (L = N,N′,N″-trimethyl-1,4,7-triazacyclononane) with Na2SO4, Na2SO3/NaClO4, and Na2SeO3/NaClO4 in aqueous solution affords the binuclear oxo bridged complexes [L2Fe2(μ-Ο)(μ-SΟ4)2]·3Η2Ο (1), [L2Fe2(μ-O)(μ-SO3)2]·5/3NaClO4·(H2O)3.67 (2), [L2Fe2(μ-O)(μ-SeO3)2](NaClO4)2.75·5H2O (3). The reaction of LFeCl3 in dry methanol with Na2SO4 yields yellow crystals of [L2Fe2(μ-SO4)3] · 2 H2O (4). The crystal structures of 1 and 2 have been determined by X-ray crystallography. Crystals of 1, 2, and 3 consist of neutral, binuclear μ-oxo bridged diiron(III) complexes which contain two additional O,O′-coordinated sulfato, sulfito, and selenito bridging ligands, respectively. The high spin ferric ions in 1, 2, and 3 are strongly intramolecularly antiferromagnetically spin exchange coupled with J values of —97(1), -104(2), and —104(2) cm-1 (H = —2JŜ,·Ŝ2, S1 = S2 = 5/2), respectively. 4 contains three μ-sulfato bridges between two FeIII ions. Only a very weak antiferromagnetic coupling has been detected (J = —5.5(5) cm-1). Complex 1 serves as a model compound for the diiron(III) complex of the sulfate treated, oxidized form of the biomolecule uteroferrin.
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2

Kelly, Norman, Marco Wenzel, Thomas Doert, Kerstin Gloe, Jan J. Weigand, Leonard F. Lindoy, and Karsten Gloe. "Unique Occurrence of Cationic and Anionic Bis-1,2-diaminocyclohexane Copper(II) Units in a Double Complex Salt." Australian Journal of Chemistry 69, no. 5 (2016): 533. http://dx.doi.org/10.1071/ch15697.

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The reaction of (±)-trans-diaminocyclohexane (dach) with copper(ii) sulfate in water resulted in the spontaneous formation of a double complex salt of type [Cu(dach)2(H2O)2][Cu(dach)2(SO4)2]·6H2O, whose X-ray structure confirmed the presence of the same square-planar Cu(dach)22+ coordination motif in both the complex cation and anion. Each copper centre adopts a Jahn–Teller-distorted octahedral geometry. Both axial positions of the metal centre in the complex cation are occupied by water molecules, whereas two monodentate sulfato ions occupy the corresponding sites in the complex anion, leading to a trans N4O2-donor coordination environment in each ion.
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3

Stoeckli-Evans, Helen, Olha Sereda, Antonia Neels, Sebastien Oguey, Catherine Ionescu, and Yvan Jacquier. "In situsingle-crystal to single-crystal (SCSC) transformation of the one-dimensional polymercatena-poly[[diaqua(sulfato)copper(II)]-μ2-glycine] into the two-dimensional polymer poly[μ2-glycine-μ4-sulfato-copper(II)]." Acta Crystallographica Section C Structural Chemistry 70, no. 11 (October 15, 2014): 1057–63. http://dx.doi.org/10.1107/s2053229614021123.

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The one-dimensional coordination polymercatena-poly[diaqua(sulfato-κO)copper(II)]-μ2-glycine-κ2O:O′], [Cu(SO4)(C2H5NO2)(H2O)2]n, (I), was synthesized by slow evaporation under vacuum of a saturated aqueous equimolar mixture of copper(II) sulfate and glycine. On heating the same blue crystal of this complex to 435 K in an oven, its aspect changed to a very pale blue and crystal structure analysis indicated that it had transformed into the two-dimensional coordination polymer poly[(μ2-glycine-κ2O:O′)(μ4-sulfato-κ4O:O′:O′′:O′′)copper(II)], [Cu(SO4)(C2H5NO2)]n, (II). In (I), the CuIIcation has a pentacoordinate square-pyramidal coordination environment. It is coordinated by two water molecules and two O atoms of bridging glycine carboxylate groups in the basal plane, and by a sulfate O atom in the apical position. In complex (II), the CuIIcation has an octahedral coordination environment. It is coordinated by four sulfate O atoms, one of which bridges two CuIIcations, and two O atoms of bridging glycine carboxylate groups. In the crystal structure of (I), the one-dimensional polymers, extending along [001], are linkedviaN—H...O, O—H...O and bifurcated N—H...O,O hydrogen bonds, forming a three-dimensional framework. In the crystal structure of (II), the two-dimensional networks are linkedviabifurcated N—H...O,O hydrogen bonds involving the sulfate O atoms, forming a three-dimensional framework. In the crystal structures of both compounds, there are C—H...O hydrogen bonds present, which reinforce the three-dimensional frameworks.
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4

Mezei, Gellert. "Sulfate-bridged dimeric trinuclear copper(II)–pyrazolate complex with three different terminal ligands." Acta Crystallographica Section E Crystallographic Communications 72, no. 8 (July 8, 2016): 1064–67. http://dx.doi.org/10.1107/s2056989016010719.

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The reaction of CuSO4·5H2O, 4-chloropyrazole (4-Cl-pzH) and triethylamine (Et3N) in dimethylformamide (DMF) produced crystals of diaquahexakis(μ-4-chloropyrazolato-κ2N:N′)bis(N,N-dimethylformamide)di-μ3-hydroxido-bis(μ4-sulfato-κ4O:O′:O′′:O′′)hexacopper(II)N,N-dimethylformamide tetrasolvate dihydrate, [Cu3(OH)(SO4)(C3H2ClN2)3(C3H7NO)(H2O)]2·4C3H7NO·2H2O. The centrosymmetric dimeric molecule consists of two trinuclear copper–pyrazolate units bridged by two sulfate ions. The title compound provides the first example of a trinuclear copper–pyrazolate complex with three different terminal ligands on the Cu atoms, and also the first example of such complex with a strongly binding basal sulfate ion. Within each trinuclear unit, the CuIIatoms are bridged by μ-pyrazolate groups and a central μ3-OH group, and are coordinated by terminal sulfate, H2O and DMF ligands, respectively. Moreover, the sulfate O atoms coordinate at the apical position to the Cu atoms of the symmetry-related unit, providing square–pyramidal coordination geometry around each copper cation. The metal complex and solvent molecules are involved in O—H...O hydrogen bonds, leading to a two-dimensional network parallel to (10-1).
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5

Liu, Ting, Yi-An Wang, Qing Zang, and Guo-Qing Zhong. "Hydrothermal Synthesis, Structural Characterization, and Interaction Mechanism with DNA of Copper(II) Complex Containing 2,2′-Bipyridine." Bioinorganic Chemistry and Applications 2018 (2018): 1–10. http://dx.doi.org/10.1155/2018/8459638.

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A Cu(II) complex [Cu(bipy)(H2O)2(SO4)]n (bipy = 2,2′-bipyridine) was synthesized by hydrothermal method and characterized structurally by elemental analyses, single crystal X-ray diffraction, infrared spectra, and thermogravimetry and differential scanning calorimetry. The Cu(II) was hexacoordinated by two N atoms from bipy, two O atoms from different sulfate radical anions, and two O atoms from two water molecules, forming a slightly distorted octahedral geometry, and bridged by sulfato groups into polymeric chains. Under the condition of physiological pH, the interaction mechanism between the complex and hsDNA was explored with acridine orange as a fluorescence probe by spectroscopic methods. The binding modes between the complex and hsDNA were the electrostatic and embedded modes.
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6

Zeghouan, Ouahida, Mohamed AbdEsselem Dems, Seifeddine Sellami, Hocine Merazig, and Jean Claude Daran. "A strongly fluorescent NiII complex with 2-(2-hydroxyethyl)pyridine ligands: synthesis, characterization and theoretical analysis and comparison with a related polymeric CuII complex." Acta Crystallographica Section E Crystallographic Communications 74, no. 8 (July 6, 2018): 1042–48. http://dx.doi.org/10.1107/s2056989018009301.

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The synthesis and characterization of diaquabis[2-(2-hydroxyethyl)pyridine-κ2 N,O)nickel(II) dinitrate, [Ni(C7H9NO)2(H2O)2](NO3)2, under ambient conditions is reported and compared with catena-poly[[bis[2-(2-hydroxyethyl)pyridine-κ2 N,O]copper(II)]-μ-sulfato-κ2 O:O′], [Cu(C7H9NO)2(SO4)] n [Zeghouan et al. (2016). Private communication (refcode 1481676). CCDC, Cambridge, England]. In the two complexes, the 2-(2-hydroxyethyl)pyridine ligands coordinate the metal ions through the N atom of the pyridine ring and the O atom of the hydroxy group, creating a chelate ring. The NiII or CuII ion lies on an inversion centre and exhibits a slightly distorted MO4N2 octahedral coordination geometry, build up by O and N atoms from two 2-(2-hydroxyethyl)pyridine ligands and two water molecules or two O atoms belonging to sulfate anions. The sulfate anion bridges the CuII ions, forming a polymeric chain. The photoluminescence properties of these complexes have been studied on as-synthesized samples and reveal that both compounds display a strong blue-light emission with maxima around 497 nm. From DFT/TDDFT studies, the blue emission appears to be derived from the ligand-to-metal charge-transfer (LMCT) excited state. In addition, the IR spectroscopic properties and thermogravimetric behaviours of both complexes have been investigated.
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7

Zheng, Yue-Qing, and Jian-Li Lin. "A New Sulfato-bridged Manganese(II) Phenanthroline Complex: [Mn(phen)(H2O)2(SO4)]." Zeitschrift für anorganische und allgemeine Chemie 629, no. 2 (February 2003): 185–87. http://dx.doi.org/10.1002/zaac.200390028.

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8

Zasłona, Halina, Piotr Drożdżewski, and Maciej Barys. "A helical coordination polymer of zinc(II), 4-hydroxybenzohydrazide and sulfate ions." Acta Crystallographica Section C Crystal Structure Communications 69, no. 3 (February 5, 2013): 229–31. http://dx.doi.org/10.1107/s0108270113002758.

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In the structure of the novel zinc complexcatena-poly[[diaqua(4-hydroxybenzohydrazide)zinc(II)]-μ-sulfato], [Zn(SO4)(C7H8N2O2)(H2O)2]n, the complex cations are linked by sulfate counter-ions into helical polymeric chains extending along thebaxis. Each helix is stabilized by six intrachain hydrogen bonds involving stronger O—H...O (1.83–2.06 Å) and weaker N—H...O (2.20–2.49 Å) interactions. The ZnIIatom displays a distorted octahedral geometry formed by the 4-hydroxybenzohydrazide ligand, two water molecules and two SO42−ions, which is very similar to the metal-atom environment in a previously reported CoIIcomplex [Zasłona, Drożdżewski & Kubiak (2010).J. Mol. Struct.982, 1–8], especially the Zn—O and Zn—N bond lengths of 2.0453 (12)–2.1602 (9) and 2.1118 (12) Å, respectively.
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9

Matsushima, Yoshiyuki, Akio Matsunaga, Kazuhiro Sakai, and Akitsugu Okuwaki. "Potentiometric Studies on Sulfato Complex of Aluminium(III) in Aqueous Solution at Elevated Temperatures." Bulletin of the Chemical Society of Japan 61, no. 12 (December 1988): 4259–63. http://dx.doi.org/10.1246/bcsj.61.4259.

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10

Vicente, C. P., P. Zancan, L. L. Peixoto, R. Alves-Sá, F. S. Araújo, P. A. S. Mourão, and M. S. G. Pavão. "Unbalanced Effects of Dermatan Sulfates with Different Sulfation Patterns on Coagulation, Thrombosis and Bleeding." Thrombosis and Haemostasis 86, no. 11 (2001): 1215–20. http://dx.doi.org/10.1055/s-0037-1616054.

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SummaryWe compared the anticoagulant, antithrombotic and bleeding effects of highly sulfated dermatan sulfates from invertebrates and their mammalian counterpart. An invertebrate dermatan sulfate containing 2-O-sulfated α-L-iduronic acid and 4-O-sulfated N-acetyl-β-D-galactosamine residues is a potent anticoagulant due to a high heparin cofactor II activity. It inhibits thrombin due to the formation of a covalent complex with heparin cofactor II, as in the case of mammalian dermatan sulfate, but the effect occurs at lower concentrations for the invertebrate polysaccharide. Surprisingly, the invertebrate dermatan sulfate has a lower potency to prevent thrombus formation on an experimental model and a lower bleeding effect in rats than the mammalian dermatan sulfate. In contrast, another invertebrate dermatan sulfate, also enriched in 2-O-sulfated α-L-iduronic acid, but in this case sulfated at O-6 position of the N-acetyl-β-D-galactosamine units, has no in vitro or in vivo anticoagulant activity, does not prevent thrombus formation but shows a bleeding effect similar to the mammalian glycosaminoglycan. Overall, these results demonstrate unbalanced effects of dermatan sulfates with different sulfation patterns on coagulation, thrombosis and bleeding, and raise interesting questions concerning the relationship among these three biological actions of sulfated polysaccharides.
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11

Holczbauer, Tamas, Attila Domjan, and Csaba Fodor. "Crystal structure of diaquatris(1-ethyl-1H-imidazole-κN3)(sulfato-κO)nickel(II)." Acta Crystallographica Section E Crystallographic Communications 72, no. 3 (February 20, 2016): 374–77. http://dx.doi.org/10.1107/s2056989016002863.

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In the title complex, [Ni(SO4)(C5H8N2)3(H2O)2], the NiIIion is coordinated by three facial 1-ethyl-1H-imidazole ligands, one monodentate sulfate ligand and two water molecules in a slightly distorted octahedral coordination environment. In the crystal, two pairs of O—H...O hydrogen bonds link complex molecules, forming inversion dimers incorporatingR24(8),R22(8) andR22(12) rings. The dimeric unit also contains two symmetry-unique intramolecular O—H...O hydrogen bonds. In addition, weak C—H...O hydrogen bonds, weak C—H...π interactions and π–π interactions with a centroid–centroid distance of 3.560 (2) Å combine to form a three-dimensional network. One of the ethyl groups is disordered over two sets of sites with occupancies in the ratio 0.586 (7):0.414 (7).
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12

Altaf, M., H. Stoeckli-Evans, G. Murtaza, A. A. Isab, S. Ahmad, and M. A. Shaheen. "Structural characterization of a cadmium(II)-sulfato complex, [Cd(N,N′-diethyl thiourea)4(SO4)]." Journal of Structural Chemistry 52, no. 3 (June 2011): 625–30. http://dx.doi.org/10.1134/s0022476611030267.

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13

Rochon, F. D., and R. Melanson. "Molecular and crystal structure of a platinum(II) complex with aquo and sulfate ligands: aquo(N,N'-dimethylethylenediamine)(sulfato)platinum(II) hydrate." Inorganic Chemistry 26, no. 7 (April 1987): 989–92. http://dx.doi.org/10.1021/ic00254a006.

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14

Papatriantafyllopoulou, Constantina, Catherine P. Raptopoulou, Aris Terzis, Jozef F. Janssens, Spyros P. Perlepes, and Evy Manessi-Zoupa. "Reactions of Nickel (II) Sulfate Hexahydrate with Methyl(2-pyridyl)ketone Oxime: Two Mononuclear Sulfato Complexes Containing the Neutral Ligand." Zeitschrift für Naturforschung B 62, no. 9 (September 1, 2007): 1123–32. http://dx.doi.org/10.1515/znb-2007-0904.

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The reactions of methyl(2-pyridyl)ketone oxime, (py)C(Me)NOH, with nickel(II) sulfate hexahydrate, in the absence of an external base, have been investigated. The reaction between equimolar quantities of NiSO4 ·6 H2O and (py)C(Me)NOH in H2O leads to the mononuclear complex [Ni(SO4){(py)C(Me)NOH}(H2O)3] ·H2O (1 ·H2O), while an excess of the organic ligand affords the 1 : 2 compound [Ni(SO4){(py)C(Me)NOH}2(H2O)] ·H2O (2 ·H2O). The structures of both compounds have been determined by single crystal X-ray diffraction. In both complexes the organic ligand chelates through its nitrogen atoms and the sulfate anion acts as a monodentate ligand. The thermal decomposition of complexes 1 ·H2O and 2 ·H2O has been studied. The IR data are discussed in terms of the nature of bonding and the structures of the two complexes.
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15

RUDOLPH, W., and S. SCHOENHERR. "ChemInform Abstract: Raman and IR Spectroscopic Investigations on Aluminum Salt Solutions. Part 2. Sulfato-Complex Formation in Aluminum Sulfate Solutions and Hydrated Melts." ChemInform 23, no. 9 (August 22, 2010): no. http://dx.doi.org/10.1002/chin.199209004.

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16

Real, J. "Studies on metal-drug complexes. Crystal structure and characterization of μ-sulfato bromazepam copper(II) complex." Journal of Inorganic Biochemistry 31, no. 3 (November 1987): 221–28. http://dx.doi.org/10.1016/0162-0134(87)80007-7.

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17

Yu, Jian. "catena-Poly[[diaqua(1H-imidazo[4,5-f][1,10]phenanthroline)cobalt(II)]-μ-sulfato]." Acta Crystallographica Section E Structure Reports Online 65, no. 6 (May 7, 2009): m618. http://dx.doi.org/10.1107/s1600536809016419.

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The CoIIion in the title complex, [Co(SO4)(C13H8N4)(H2O)2]n, has a slightly distorted octahedral coordination environment formed by two O atoms from two symmetry-related bridging sulfate ligands, two N atoms from a bis-chelating 1H-imidazo[4,5-f][1,10]phenanthroline (IPL) ligand and two O atoms from coordinated water molecules. The bridging sulfate ligands connect CoIIions to form a one-dimensional chain along theb-axis direction. In the crystal structure, intermolecular O—H...O, O—H...N and N—H...O hydrogen bonds link the chains into a three-dimensional network.
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18

Setifi, Zouaoui, Huey Chong Kwong, Edward R. T. Tiekink, Thierry Maris, and Fatima Setifi. "fac-Triaqua(1,10-phenanthroline-κ2 N,N′)(sulfato-κO)cobalt(II): crystal structure, Hirshfeld surface analysis and computational study." Acta Crystallographica Section E Crystallographic Communications 76, no. 6 (May 15, 2020): 835–40. http://dx.doi.org/10.1107/s2056989020006271.

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The CoII atom in the title complex, [Co(SO4)(C12H8N2)(H2O)3] (or C12H14CoN2O7S), is octahedrally coordinated within a cis-N2O4 donor set defined by the chelating N-donors of the 1,10-phenanthroline ligand, sulfate-O and three aqua-O atoms, the latter occupying an octahedral face. In the crystal, supramolecular layers lying parallel to (110) are sustained by aqua-O—H...O(sulfate) hydrogen bonding. The layers stack along the c-axis direction with the closest directional interaction between them being a weak phenanthroline-C—H...O(sulfate) contact. There are four significant types of contact contributing to the calculated Hirshfeld surface: at 44.5%, the major contribution comes from O—H...O contacts followed by H...H (28.6%), H...C/C...H (19.5%) and C...C (5.7%) contacts. The dominance of the electrostatic potential force in the molecular packing is also evident in the calculated energy frameworks. The title complex is isostructural with its manganese, zinc and cadmium containing analogues and isomeric with its mer-triaqua analogue.
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19

Foersterling, Horst Dieter, and Linda Stuk. "Effects of cerium(4+)/sulfato complex formation in the Belousov-Zhabotinskii reaction: ESR studies of malonyl radical formation." Journal of Physical Chemistry 96, no. 7 (April 1992): 3067–72. http://dx.doi.org/10.1021/j100186a054.

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20

Chiang, Wen-Chi, Fu-Yu Tsai, Yuan-Chung Cheng, Gene-Hsiang Lee, Yu Wang, and Jwu-Ting Chen. "Organometallic sulfato- and phosphato-allyl complexes synthesized from regioselective addition of oxyacids to an η3-allenyl–propargyl complex." Inorganica Chimica Acta 334 (May 2002): 213–18. http://dx.doi.org/10.1016/s0020-1693(02)00762-4.

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21

Rasmussen, S. B., K. M. Eriksen, and R. Fehrmann. "Sulfato Complex Formation of V(V) and V(IV) in Pyrosulfate Melts Investigated by Potentiometry and Spectroscopic Methods." Journal of Physical Chemistry B 103, no. 51 (December 1999): 11282–89. http://dx.doi.org/10.1021/jp9927101.

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22

Lamanna, William C., Rebecca J. Baldwin, Michael Padva, Ina Kalus, Gerdy ten Dam, Toin H. van Kuppevelt, John T. Gallagher, Kurt von Figura, Thomas Dierks, and Catherine L. R. Merry. "Heparan sulfate 6-O-endosulfatases: discrete in vivo activities and functional co-operativity." Biochemical Journal 400, no. 1 (October 27, 2006): 63–73. http://dx.doi.org/10.1042/bj20060848.

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HS (heparan sulfate) is essential for normal embryonic development. This requirement is due to the obligatory role for HS in the signalling pathways of many growth factors and morphogens that bind to sulfated domains in the HS polymer chain. The sulfation patterning of HS is determined by a complex interplay of Golgi-located N- and O-sulfotransferases which sulfate the heparan precursor and cell surface endosulfatases that selectively remove 6-O-sulfates from mature HS chains. In the present study we generated single or double knock-out mice for the two murine endosulfatases mSulf1 and mSulf2. Detailed structural analysis of HS from mSulf1−/− fibroblasts showed a striking increase in 6-O-sulfation, which was not seen in mSulf2−/− HS. Intriguingly, the level of 6-O-sulfation in the double mSulf1−/−/2−/− HS was significantly higher than that observed in the mSulf1−/− counterpart. These data imply that mSulf1 and mSulf2 are functionally co-operative. Unlike their avian orthologues, mammalian Sulf activities are not restricted to the highly sulfated S-domains of HS. Mitogenesis assays with FGF2 (fibroblast growth factor 2) revealed that Sulf activity decreases the activating potential of newly-synthesized HS, suggesting an important role for these enzymes in cell growth regulation in embryonic and adult tissues.
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23

Moushi, Eleni, Constantinos G. Efthymiou, Spyros P. Perlepes, and Constantina Papatriantafyllopoulou. "Synthesis and Structural Characterization of a New Tetranuclear Nickel(II) Sulfato Complex Containing the Anionic Form of Di-2-Pyridyl Ketone Oxime." International Journal of Inorganic Chemistry 2011 (April 20, 2011): 1–9. http://dx.doi.org/10.1155/2011/606271.

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The preparation and crystal structure of a tetranuclear Ni(II) sulfato cluster containing the anion of di-2-pyridyl ketone oxime, (py)2CNO−, are reported. Treatment of NiSO4·6H2O with one equivalent of (py)2CNOH and one equivalent of NEt3 in MeOH leads to the compound [Ni4{(py)2CNO}4(SO4)2(MeOH)4] (1) in moderate yield. The metal ions are linked together by two 3.2111 and two 2.1110 (Harris notation) (py)2CNO− ligands, as well as two 2.1100 SO42− ions to create a rare metallacrown-type (12-MC-4) ring. Strong H-bond intermolecular interactions in 1 lead to the formation of a 1D chain along the axis. Characteristic IR bands are discussed in terms of the known structure of 1.
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Rasmussen, S. B., K. M. Eriksen, and R. Fehrmann. "ChemInform Abstract: Sulfato Complex Formation of V(V) and V(IV) in Pyrosulfate Melts Investigated by Potentiometry and Spectroscopic Methods." ChemInform 31, no. 14 (June 9, 2010): no. http://dx.doi.org/10.1002/chin.200014019.

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25

Rahmani, A., M. A. Romero, J. M. Salas, M. Quirós, and G. Alvarez de Cienfuegos. "A new example of μ3-sulfato coordination in a Cd(II) complex of 5,7-dimethyl[1,2,4]triazolo[1,5-a]pyrimidine (dmtp). Characterisation and biological activity of several metal complexes of dmtp containing the sulfato anion." Inorganica Chimica Acta 247, no. 1 (June 1996): 51–55. http://dx.doi.org/10.1016/0020-1693(95)04829-4.

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26

Bera, Manindranath, Ashley B. S. Curtiss, Ghezai T. Musie, and Douglas R. Powell. "A new self-assembled μ6-sulfato hexanuclear cobalt(II) complex of a symmetric dinucleating ligand: Synthesis and X-ray structural analysis." Inorganic Chemistry Communications 11, no. 9 (September 2008): 1033–36. http://dx.doi.org/10.1016/j.inoche.2008.05.029.

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27

Sofetis, Andreas, Giannis S. Papaefstathiou, Aris Terzis, Catherine P. Raptopoulou, and Theodoros F. Zafiropoulos. "Preparation, Crystal Structure and Spectroscopic Characterization of [Ga(OH)(SO4)(terpy)(H2O)] · H2O (terpy=2,2’:6’,2-Terpyridine): The First Characterized Gallium(III) Sulfato Complex." Zeitschrift für Naturforschung B 59, no. 3 (March 1, 2004): 291–97. http://dx.doi.org/10.1515/znb-2004-0310.

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The reaction of Ga2(SO4)3·18H2O and excess 2,2′:6′,2″-terpyridine (terpy) in MeOH / H2O leads to [Ga(OH)(SO4)(terpy)(H2O)]·H2O (1·H2O] in good yield. The structure of the complex has been determined by single-crystal X-ray crystallography. The GaIII atom in 1·H2O is 6-coordinate and ligation is provided by one terdentate terpy molecule, one monodentate sulfate, one terminal hydroxide and one terminal H2O molecule; the coodination polyhedron about the metal is described as a distorted octahedron. There is an extensive hydrogen-bonding network in the crystal structure which generates corrugated layers parallel to bc. The new complex was characterized by IR and 1H NMR spectroscopy. The spectroscopic data are discussed in terms of the nature of bonding
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Li, Guangshi, Xiaolu Xiong, Liping Wang, Lang Che, Lizhen Wei, Hongwei Cheng, Xingli Zou, et al. "Sulfation Roasting of Nickel Oxide–Sulfide Mixed Ore Concentrate in the Presence of Ammonium Sulfate: Experimental and DFT Studies." Metals 9, no. 12 (November 25, 2019): 1256. http://dx.doi.org/10.3390/met9121256.

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Sulfation roasting, a common activation technique, is a potential method for cleaner production of nickel from complex low-grade ores. In this study, nickel oxide–sulfide mixed ore concentrate was roasted with the addition of ammonium sulfate under a static air atmosphere, and the roasted products were leached by water, in order to evaluate the extraction of metals. The ammonium sulfate activation roasting was investigated thoroughly and systematically by thermogravimetry–differential scanning calorimetry, X-ray diffraction, and scanning electron microscopy. Particularly, the interface sulfation behavior and path were studied by the density functional theory (DFT) method. The results showed that a large amount of nonferrous metal sulfate (70% Ni, 89% Co, and 90% Cu) was generated, while iron was almost entirely transformed into iron oxide under appropriate roasting conditions of adding ammonium sulfate at a mass ratio of 200%, heating to 650 °C at 10 °C/min, and holding for 120 min. It was found that activation of ammonium sulfate can take two different paths: one in which ammonium sulfate directly reacts with raw ores below 500 °C and the other in which the SO2 decomposed from sulfates (ammonium sulfate, intermediate ammonium ferric sulfate, and ferric sulfate) reacts with the intermediate metal sulfides (NiS and Cu2S). The interface sulfation mechanism of NiS and Cu2S was investigated deeply by DFT method, which showed that there are two paths of sulfation for NiS or Cu2S, and both of them are thermodynamically favored. Thus, a thorough and systematic investigation of ammonium sulfate activation roasting of nickel oxide–sulfide mixed ore is provided; this might be a potential basis for future industrial applications of ammonium sulfate activation roasting techniques in complex mineral metallurgy.
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29

Brandan, E., M. Maldonado, J. Garrido, and N. C. Inestrosa. "Anchorage of collagen-tailed acetylcholinesterase to the extracellular matrix is mediated by heparan sulfate proteoglycans." Journal of Cell Biology 101, no. 3 (September 1, 1985): 985–92. http://dx.doi.org/10.1083/jcb.101.3.985.

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Heparan sulfate and heparin, two sulfated glycosaminoglycans (GAGs), extracted collagen-tailed acetylcholinesterase (AChE) from the extracellular matrix (ECM) of the electric organ of Discopyge tschudii. The effect of heparan sulfate and heparin was abolished by protamine; other GAGs could not extract the esterase. The solubilization of the asymmetric AChE apparently occurs through the formation of a soluble AChE-GAG complex of 30S. Heparitinase treatment but not chondroitinase ABC treatment of the ECM released asymmetric AChE forms. This provides direct evidence for the vivo interaction between asymmetric AChE and heparan sulfate residues of the ECM. Biochemical analysis of the electric organ ECM showed that sulfated GAGs bound to proteoglycans account for 5% of the total basal lamina. Approximately 20% of the total GAGs were susceptible to heparitinase or nitrous acid oxidation which degrades specifically heparan sulfates, and approximately 80% were susceptible to digestion with chondroitinase ABC, which degrades chondroitin-4 and -6 sulfates and dermatan sulfate. Our experiments provide evidence that asymmetric AChE and carbohydrate components of proteoglycans are associated in the ECM; they also indicate that a heparan sulfate proteoglycan is involved in the anchorage of the collagen-tailed AChE to the synaptic basal lamina.
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30

Snoeck, Carla, Christel Verreth, Ismael Hernández-Lucas, Esperanza Martínez-Romero, and Jos Vanderleyden. "Identification of a Third Sulfate Activation System in Sinorhizobium sp. Strain BR816: the CysDN Sulfate Activation Complex." Applied and Environmental Microbiology 69, no. 4 (April 2003): 2006–14. http://dx.doi.org/10.1128/aem.69.4.2006-2014.2003.

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ABSTRACT Sinorhizobium sp. strain BR816 possesses two nodPQ copies, providing activated sulfate (3′-phosphoadenosine-5′-phosphosulfate [PAPS]) needed for the biosynthesis of sulfated Nod factors. It was previously shown that the Nod factors synthesized by a nodPQ double mutant are not structurally different from those of the wild-type strain. In this study, we describe the characterization of a third sulfate activation locus. Two open reading frames were fully characterized and displayed the highest similarity with the Sinorhizobium meliloti housekeeping ATP sulfurylase subunits, encoded by the cysDN genes. The growth characteristics as well as the levels of Nod factor sulfation of a cysD mutant (FAJ1600) and a nodP1 nodQ2 cysD triple mutant (FAJ1604) were determined. FAJ1600 shows a prolonged lag phase only with inorganic sulfate as the sole sulfur source, compared to the wild-type parent. On the other hand, FAJ1604 requires cysteine for growth and produces sulfate-free Nod factors. Apigenin-induced nod gene expression for Nod factor synthesis does not influence the growth characteristics of any of the strains studied in the presence of different sulfur sources. In this way, it could be demonstrated that the “household” CysDN sulfate activation complex of Sinorhizobium sp. strain BR816 can additionally ensure Nod factor sulfation, whereas the symbiotic PAPS pool, generated by the nodPQ sulfate activation loci, can be engaged for sulfation of amino acids. Finally, our results show that rhizobial growth defects are likely the reason for a decreased nitrogen fixation capacity of bean plants inoculated with cysD mutant strains, which can be restored by adding methionine to the plant nutrient solution.
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31

Valentová, Kateřina, Kateřina Purchartová, Lenka Rydlová, Lenka Roubalová, David Biedermann, Lucie Petrásková, Alena Křenková, et al. "Sulfated Metabolites of Flavonolignans and 2,3-Dehydroflavonolignans: Preparation and Properties." International Journal of Molecular Sciences 19, no. 8 (August 9, 2018): 2349. http://dx.doi.org/10.3390/ijms19082349.

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Silymarin, an extract from milk thistle (Silybum marianum) fruits, is consumed in various food supplements. The metabolism of silymarin flavonolignans in mammals is complex, the exact structure of their metabolites still remains partly unclear and standards are not commercially available. This work is focused on the preparation of sulfated metabolites of silymarin flavonolignans. Sulfated flavonolignans were prepared using aryl sulfotransferase from Desulfitobacterium hafniense and p-nitrophenyl sulfate as a sulfate donor and characterized by high-resolution mass spectrometry (HRMS) and nuclear magnetic resonance (NMR). Their 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and N,N-dimethyl-p-phenylenediamine (DMPD) radical scavenging; ferric (FRAP) and Folin–Ciocalteu reagent (FCR) reducing activity; anti-lipoperoxidant potential; and effect on the nuclear erythroid 2-related factor 2 (Nrf2) signaling pathway were examined. Pure silybin A 20-O-sulfate, silybin B 20-O-sulfate, 2,3-dehydrosilybin-20-O-sulfate, 2,3-dehydrosilybin-7,20-di-O-sulfate, silychristin-19-O-sulfate, 2,3-dehydrosilychristin-19-O-sulfate, and silydianin-19-O-sulfate were prepared and fully characterized. Sulfated 2,3-dehydroderivatives were more active in FCR and FRAP assays than the parent compounds, and remaining sulfates were less active chemoprotectants. The sulfated flavonolignans obtained can be now used as authentic standards for in vivo metabolic experiments and for further research on their biological activity.
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32

Ramesh, Hema, K. Parthipan, and P. Sambasiva Rao. "Substitutional location for a vanadyl ion in three water coordinated triaqua(1,10-phenanthroline-k2N,N′) (sulfato-kO)magnesium(II) complex: a rare observation." Radiation Effects and Defects in Solids 167, no. 3 (March 2012): 184–92. http://dx.doi.org/10.1080/10420150.2011.638295.

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33

Trask, Barbara Crippes, Timothy M. Trask, Thomas Broekelmann, and Robert P. Mecham. "The Microfibrillar Proteins MAGP-1 and Fibrillin-1 Form a Ternary Complex with the Chondroitin Sulfate Proteoglycan Decorin." Molecular Biology of the Cell 11, no. 5 (May 2000): 1499–507. http://dx.doi.org/10.1091/mbc.11.5.1499.

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MAGP-1 and fibrillin-1, two protein components of extracellular microfibrils, were shown by immunoprecipitation studies to interact with the chondroitin sulfate proteoglycan decorin in the medium of cultured fetal bovine chondrocytes. Decorin interacted with each protein individually and with both proteins together to form a ternary complex. Expression of truncated fibrillin-1 proteins in Chinese hamster ovary cells localized proteoglycan binding to an amino-terminal region near the proline-rich domain. A spatially analogous fibrillin-2 truncated protein did not coprecipitate the same sulfated molecule, suggesting that chondroitin sulfate proteoglycan binding in this region is specific for fibrillin-1. An interaction between fibrillin and MAGP-1 was also observed under culture conditions that abrogated decorin secretion, suggesting that the two microfibrillar proteins can associate in the absence of the proteoglycan. Sulfation of matrix proteins is important for elastic fiber assembly because inhibition of sulfation was shown to prevent microfibrillar protein incorporation into the extracellular matrix of cultured cells.
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34

Hills, Elaine F., David T. Richens, and A. Geoffrey Sykes. "Kinetic studies on substitution reactions of Delepine's triangular mixed-valence iridium(III, IV, IV) complex triaqua(.mu.3-nitrido)(hexa-.mu.-sulfato)triiridate(4-)." Inorganic Chemistry 25, no. 18 (August 1986): 3144–48. http://dx.doi.org/10.1021/ic00238a010.

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35

Panin, G., S. Naia, R. Dall'Amico, L. Chiandetti, F. Zachello, C. Catassi, L. Felici, and G. V. Coppa. "Simple spectrophotometric quantification of urinary excretion of glycosaminoglycan sulfates." Clinical Chemistry 32, no. 11 (November 1, 1986): 2073–76. http://dx.doi.org/10.1093/clinchem/32.11.2073.

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Abstract We describe a simple, rapid, precise, and sensitive spectrophotometric method for measuring urinary glycosaminoglycan (GAG) sulfate excretion. The GAG sulfates are precipitated with cetylpyridinium chloride, resuspended in water, and mixed with the basic dye 1,9-dimethylmethylene blue to produce a complex with the polyanionic molecule of sulfated GAGs. Absorbance is read at 535 nm. The standard curve for reaction was linear up to 12 micrograms of the different GAGs: dermatan sulfate, heparan sulfate, keratan sulfate, chondroitin 4-sulfate, and chondroitin 6-sulfate. Within- and between-run precision (CV), measured at three different GAG concentrations (normal and pathological), varied from 1.6% to 2.5% and from 1.8% to 4.5%, respectively. Analytical recovery ranged from 71% to 107%. Urinary GAG excretion, measured by this procedure, correlates (r = 0.837; p less than 0.001) with the values obtained with the borate-carbazole reaction (Anal Biochem 1962;4:330-4).
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36

Fonseca, Roberto, Stephan-Nicollas Oliveira, Vitor Pomin, André Mecawi, Iracema Araujo, and Paulo Mourão. "Effects of oversulfated and fucosylated chondroitin sulfates on coagulation." Thrombosis and Haemostasis 103, no. 05 (2010): 994–1004. http://dx.doi.org/10.1160/th09-10-0734.

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SummaryWe report the effects of a chemically oversulfated chondroitin sulfate and a naturally fucosylated chondroitin sulfate on the coagulation system. The former has been recently identified as a contaminant of heparin preparations and the latter has been proposed as an alternative anticoagulant. The mechanism of action of these polymers on coagulation is complex and target different components of the coagulation system. They have serpin-independent anticoagulant activity, which preponderates in plasma. They also have serpin-dependent anticoagulant activity but differ significantly in the target coagulation protease and preferential serpin. Their anticoagulant effects differ even more markedly when tested as inhibitors of coagulation proteases using plasma as a source of serpins. It is possible that the difference is due to the high availability of fucosylated chondroitin sulfate whereas over-sulfated chondroitin sulfate has strong unspecific binding to plasma protein and low availability for the binding to serpins. When tested using a venous thrombosis experimental model, oversulfated chondroitin sulfate is less potent as an antithrombotic agent than fucosylated chondroitin sulfate. These highly sulfated chondroitin sulfates activate factor XII in in vitro assays, based on kallikrein release. However, only fucosylated chondroitin sulfate induces hypotension when intravenously injected into rats. In conclusion, the complexity of the regulatory mechanisms involved in the action of highly sulfated polysaccharides in coagulation requires their analysis by a combination of in vitro and in vivo assays. Our results are relevant due to the urgent need for new anticoagulant drugs or alternative sources of heparin.
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37

Straßmann, Sarah, Maike Passon, and Andreas Schieber. "Chemical Hemisynthesis of Sulfated Cyanidin-3-O-Glucoside and Cyanidin Metabolites." Molecules 26, no. 8 (April 8, 2021): 2146. http://dx.doi.org/10.3390/molecules26082146.

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The metabolism of anthocyanins in humans is still not fully understood, which is partly due to the lack of reference compounds. It is known that sulfation is one way of the complex phase II biotransformation mechanism. Therefore, cyanidin-3-O-glucoside and the cyanidin aglycone were chemically converted to their sulfates by reaction with sulfur trioxide-N-triethylamine complex in dimethylformamide. The reaction products were characterized by UHPLC coupled to linear ion trap and IMS-QTOF mass spectrometry. Based on MS data, retention times, and UV-Vis spectra, the compounds could tentatively be assigned to A-, C-, or B-ring sulfates. Analysis of urine samples from two volunteers after ingestion of commercial blackberry nectar demonstrated the presence of two sulfated derivatives of the cyanidin aglycone and one sulfated derivative of the cyanidin-3-O-glucoside. It was found that both the A ring and the B ring are sulfated by human enzymes. This study marks an important step toward a better understanding of anthocyanin metabolism.
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38

Malyar, Yuriy Nikolayevich, Natal'ya Yur'yevna Vasil'yeva, Aleksandr Sergeyevich Kazachenko, Galina Pavlovna Skvortsova, Irina Vladimirovna Korol'kova, and Svetlana Alekseyevna Kuznetsova. "SULFATION OF ABIES ETHANOL LIGNIN WITH COMPLEXES OF SULFUR TRIOXIDE WITH 1,4-DIOXANE AND PYRIDINE." chemistry of plant raw material, no. 3 (October 22, 2020): 5–15. http://dx.doi.org/10.14258/jcprm.2020036931.

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In this work, we optimized the process of sulfating abies ethanol lignin with complexes of sulfuric anhydride with pyridine and 1,4-dioxane. Experimentally found are the conditions for the implementation of the process of sulfation of abies ethanol lignin by complexes of sulfur trioxide with 1,4-dioxane and pyridine, providing a high sulfur content (12.0–12.6%). It was shown that a high sulfur content of 12.0–13.5% (mass.) in the obtained ethanol lignin sulfate is achieved when the ratio of the amount of chlorosulfonic acid to the amount of abies ethanol lignin is 20.22 : 1 mmol : g and the duration of the sulfation process is 60–120 min and independent of the nature of the sulfating complex. The structure and composition of water-soluble sulfated abies ethanol lignin are confirmed by FTIR spectroscopy, gel permeation chromatography and elemental analysis. In the FTIR spectra of sulfated abies ethanol lignin, in comparison with the FTIR spectra of the initial abies ethanol lignin, there are absorption bands in the region of 1270–1260, 1220–1212, 861–803 cm-1, corresponding to vibrations of sulfate groups. Compared to the initial lignin, sulfated abies ethanol lignin has a low degree of polydispersity. In particular, there was an increase in Mw c ~1.5 kDa to ~3.4 kDa in lignin sulfated for 30 min and a decrease in polydispersity from 2.59 to 1.22 compared to the initial abies ethanol lignin. With an increase in the sulfation time, the profile of the molecular mass distribution curve shifts to a high molecular weight region, with a simultaneous increase in polydispersity to 1.5 and Mw increases to ~4.3 kDa.
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39

Guerrini, Marco, Stefano Elli, Pierre Mourier, Timothy R. Rudd, Davide Gaudesi, Benito Casu, Christian Boudier, Giangiacomo Torri, and Christian Viskov. "An unusual antithrombin-binding heparin octasaccharide with an additional 3-O-sulfated glucosamine in the active pentasaccharide sequence." Biochemical Journal 449, no. 2 (December 14, 2012): 343–51. http://dx.doi.org/10.1042/bj20121309.

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The 3-O-sulfation of N-sulfated glucosamine is the last event in the biosynthesis of heparin/heparan sulfate, giving rise to the antithrombin-binding pentasaccharide sequence AGA*IA, which is largely associated with the antithrombotic activity of these molecules. The aim of the present study was the structural and biochemical characterization of a previously unreported AGA*IA*-containing octasaccharide isolated from the very-low-molecular-mass heparin semuloparin, in which both glucosamine residues of the pentasaccharide moiety located at the non-reducing end bear 3-O-sulfate groups. Two-dimensional and STD (saturation transfer difference) NMR experiments clearly confirmed its structure and identified its ligand epitope binding to antithrombin. The molecular conformation of the octasaccharide–antithrombin complex has been determined by NMR experiments and docking/energy minimization. The presence of the second 3-O-sulfated glucosamine in the octasaccharide induced more than one order of magnitude increase in affinity to antithrombin compared to the pentasaccharide AGA*IA.
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40

Butchard, James R., and Owen J. Curnow. "Aqueous chemistry of the five-coordinate zirconocene dichloride PhP(CH2CH2–η5-C5H4)2ZrCl2: X-ray structure of the sulfato complex PhP(CH2CH2–η5-C5H4)2Zr(η2-SO4)." Polyhedron 26, no. 2 (January 2007): 406–14. http://dx.doi.org/10.1016/j.poly.2006.06.031.

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41

Fonseca, Roberto, Gustavo Santos, and Paulo Mourão. "Effects of polysaccharides enriched in 2,4-disulfated fucose units on coagulation, thrombosis and bleeding." Thrombosis and Haemostasis 102, no. 11 (2009): 829–36. http://dx.doi.org/10.1160/th08-11-0773.

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SummarySulfated polysaccharides from marine invertebrates have welldefined structures and constitute a reliable class of molecules for structure-activity relationship studies.We tested the effects of two of these polysaccharides,namely a sulfated fucan and a fucosylated chondroitin sulfate, on coagulation, thrombosis and bleeding. The compounds share similar 2,4-disulfated fucose units, which are required for high anticoagulant activity in this class of polymer.These residues occur either as branches in fucosylated chondroitin sulfate or as components of the linear chain in the sulfated fucan.These polysaccharides possess anticoagulant activity but differ significantly in their mechanisms of action.The fucosylated chondroitin sulfate inhibits thrombin by heparin cofactor II, whereas sulfated fucan inhibits thrombin by both antithrombin and heparin cofactor II. In addition, these polysaccharides also have serpin-independent anticoagulant activities. Fucosylated chondroitin sulfate, but not sulfated fucan, activates factor XII. As a result of the complex anticoagulant mechanism, the invertebrate polysaccharides differ in their effects on experimental thrombosis. For instance, the sulfated fucan inhibits venous thrombosis at lower doses than fucosylated chondroitin sulfate. In contrast, fucosylated chondroitin sulfate is significantly more potent than sulfated fucan in arterial thrombosis. Finally, fucosylated chondroitin sulfate increases bleeding, while sulfated fucan has only a discrete effect. In conclusion, the location of 2,4-disulfated fucose units in the polysaccharide chains dictates the effects on coagulation, thrombosis and bleeding.
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42

Erdogan, Evrim, and Michael Kalafatis. "Identification of Sulfo-Tyrosines of Factor V." Blood 104, no. 11 (November 16, 2004): 1731. http://dx.doi.org/10.1182/blood.v104.11.1731.1731.

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Abstract The factor Va molecule is the essential cofactor of the prothrombinase complex. This complex composed of factor Xa and factor Va assembled on a platelet membrane-surface in the presence of Ca2+ ions converts membrane-bound prothrombin to thrombin. Single chain factor V does not bind factor Xa. Single-chain factor V is cleaved by thrombin first at Arg709 followed by cleavages at Arg1018 and Arg1545 to produce the heavy and light chains of the active cofactor (factor Va) and two activation peptides. Efficient thrombin cleavage and activation of factor V is essential for cofactor function and requires tyrosine sulfation. Tyrosine sulfation of factor V also appears to regulate its activity. Seven tyrosine residues in factor V, Tyr665, Tyr696, Tyr698, Tyr1494, Tyr1510, Tyr1515, and Tyr1565 have been identified as potential sites of sulfation. However, which residues are sulfated and their contribution to procofactor activation and cofactor function still remain to be elucidated. Two of the sulfation sites Tyr696 and Tyr698 are located in the acidic amino acid region near to the first required thrombin cleavage site at Arg709. Recent data demonstrated that these residues are essential for factor V activation and cofactor activity. Another acidic amino acid region, 1490–1520 is adjacent to the thrombin cleavage site at Arg1545 required for light chain formation. This region also contains three potential sulfation sites at residues 1494, 1510, and 1515 and was shown to be required for optimum procofactor activation. To ascertain which of these three residues is important for procofactor activation, site-directed mutagenesis was used to create recombinant factor V molecules with mutations 1493DY1494→AF, 1508DDY1510→AAF and 1514DY1515→AF. The clotting and cofactor activity of the 1493DY1494→AF and 1514DY1515→AF mutants was similar to the clotting activity observed with the wild type recombinant factor Va molecule following activation by thrombin or RVV-V activator. In contrast, under similar experimental conditions recombinant factor V with the substitution 1508DDY1510→AAF was deficient in its clotting activity and had impaired cofactor activity. Moreover, following prolonged incubation with thrombin, no light chain formation was observed in the factor V molecule bearing the 1508DDY1510→AAF mutation. Thus, amino acid residues 1508–1510 of factor V are required for thrombin interaction with the procofactor which in turn appears necessary for cleavage at Arg1545. Studies of sulfated proteins have shown that the effect of sulfo-tyrosines on protein structure/function can be preserved by replacing them with glutamic acid. To explicitly identify the sulfated tyrosines on the factor V molecule, we mutated Tyr696, Tyr698 and Tyr1510 to glutamic acid and transfected them into COS-7L cells. Expression was performed in the presence of media containing or devoid of sulfate. In the presence of sulfate, the cofactor and clotting activities of the DY696DY698→DEDE and DDY1510→DDE mutants, separately were similar to the wild type recombinant factor Va molecule. However, in the absence of sulfate, the wild type and the mutant recombinant factor V molecules had both impaired cofactor activity and clotting activity following their activation with thrombin. However, their respective activity was higher than the activity of the factor V molecule bearing the 1508DDY1510→AAF mutation. Our data suggest that residues 696, 698, and 1510 of factor V appear to be sulfated and might be important for procofactor activation and cofactor function.
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43

Pimpão, Rui C., M. Rita Ventura, Ricardo B. Ferreira, Gary Williamson, and Claudia N. Santos. "Phenolic sulfates as new and highly abundant metabolites in human plasma after ingestion of a mixed berry fruit purée." British Journal of Nutrition 113, no. 3 (January 9, 2015): 454–63. http://dx.doi.org/10.1017/s0007114514003511.

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Bioavailability studies are vital to assess the potential impact of bioactive compounds on human health. Although conjugated phenolic metabolites derived from colonic metabolism have been identified in the urine, the quantification and appearance of these compounds in plasma is less well studied. In this regard, it is important to further assess their potential biological activityin vivo. To address this gap, a cross-over intervention study with a mixed fruit purée (blueberry, blackberry, raspberry, strawberry tree fruit and Portuguese crowberry) and a standard polyphenol-free meal was conducted in thirteen volunteers (ten females and three males), who received each test meal once, and plasma metabolites were identified by HPLC–MS/MS. Sulfated compounds were chemically synthesised and used as standards to facilitate quantification. Gallic and caffeic acid conjugates were absorbed rapidly, reaching a maximum concentration between 1 and 2 h. The concentrations of sulfated metabolites resulting from the colonic degradation of more complex polyphenols increased in plasma from 4 h, and pyrogallol sulfate and catechol sulfate reached concentrations ranging from 5 to 20 μmat 6 h. In conclusion, phenolic sulfates reached high concentrations in plasma, as opposed to their undetected parent compounds. These compounds have potential use as biomarkers of polyphenol intake, and their biological activities need to be considered.
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44

Spiro, R. C., H. H. Freeze, D. Sampath, and J. A. Garcia. "Uncoupling of chondroitin sulfate glycosaminoglycan synthesis by brefeldin A." Journal of Cell Biology 115, no. 5 (December 1, 1991): 1463–73. http://dx.doi.org/10.1083/jcb.115.5.1463.

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Brefeldin A has dramatic, well-documented, effects on the structural and functional organization of the Golgi complex. We have examined the effects of brefeldin A (BFA) on the Golgi-localized synthesis and addition of chondroitin sulfate glycosaminoglycan carbohydrate side chains. BFA caused a dose-dependent inhibition of chondroitin sulfate glycosaminoglycan elongation and sulfation onto the core proteins of the melanoma-associated proteoglycan and the major histocompatibility complex class II-associated invariant chain. In the presence of BFA, the melanoma proteoglycan core protein was retained in the ER but still acquired complex, sialylated, N-linked oligosaccharides, as measured by digestion with endoglycosidase H and neuraminidase. The initiation of glycosaminoglycan synthesis was not affected by BFA, as shown by the incorporation of [6-3H]galactose into a protein-carbohydrate linkage region that was sensitive to beta-elimination. The ability of cells to use an exogenous acceptor, p-nitrophenyl-beta-D-xyloside, to elongate and sulfate core protein-free glycosaminoglycans, was completely inhibited by BFA. The effects of BFA were completely reversible in the absence of new protein synthesis. These experiments indicate that BFA effectively uncouples chondroitin sulfate glycosaminoglycan synthesis by segregating initiation reactions from elongation and sulfation events. Our findings support the proposal that glycosaminoglycan elongation and sulfation reactions are associated with the trans-Golgi network, a BFA-resistant, Golgi subcompartment.
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45

Zarpellon, Alessandro, Richard A. McClintock, James R. Roberts, and Zaverio M. Ruggeri. "Mechanism of α-Thrombin Binding to Platelet Glycoprotein Ibα." Blood 112, no. 11 (November 16, 2008): 2867. http://dx.doi.org/10.1182/blood.v112.11.2867.2867.

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Abstract Glycoprotein (GP) Ibα, a member of the GP Ib-IX-V receptor complex, is one of the most abundant platelet membrane receptors. Besides mediating the interaction with von Willebrand factor, which is necessary to initiate the tethering of circulating platelets to the injured vessel wall, it mediates the binding of α-thrombin. Sulfation of three tyrosine residues (Y276, Y278, Y279) is thought to be important for binding α-thrombin. With the goal of understanding the mechanism of thrombin binding to platelet GP Ib, we first generated an amino terminal (residues 1–290) GP Ibα fragment, called GPIbαN, which bears all the determinants for α-thrombin binding. In a previously published crystal structure of the GPIbαN/thrombin complex, the negatively charged sulfate groups on Y276 and Y279 were found to mediate interactions with two positively charged clusters of α-thrombin residues, namely exosites I and II.To evaluate tyrosine sulfation levels, we digested GPIbαN with Abalone sulfatase and the resulting species were analyzed by ion exchange chromatography. Digestion of the fully sulfated form (peak 4) progressively generated 3 additional species, called peak 3, peak 2 and peak 1, which were assumed to contain 2, 1 and no sulfated tyrosine residues, respectively. With time, all peak 4 could be converted to peak 1. The GPIbαN peak 4, mixed in a 3:1 ratio with α-thrombin, formed a stable complex that could be separated by gel permeation chromatography and incorporated all the α-thrombin added into the mixture. Peak 3 (the species that was previously crystallized in complex with thrombin and found to lack sulfation on Y278) formed a comparable amount of complex relative to peak 4, while peak 2 bound only 39% and peak 1 12% of the added thrombin. A degradation product of α-thrombin that lacks exosite I, γ-thrombin, formed the same amount of complex with GPIbαN peak 3 as α-thrombin, while meizothrombin, that lacks a fully functional exosite II, was unable to generate a stable complex. Moreover heparin and oligonucleotide HD22, specific inhibitors of exosite II, completely blocked complex formation, while Hirugen and oligonucleotide HD1, exosite I inhibitors, had no effect. The mutants Y279F (containing sulfotyrosine 276 and 278) and Y278F (containing sulfotyrosine 276 and 279) generated 87% and 92% of the complex as compared to WT, while the mutant Y276F (containing sulfotyrosine 278 and 279) generated only 10% of the complex. These results indicate that sulfotyrosine 276 in GPIbαN is essential for forming a complex with thrombin, a conclusion consistent with the crystal structure in which the sulfate group on Y276 mediates close contacts with exosite II. Altogether, these findings support the concept that exosite II is necessary and sufficient for the formation of a stable complex with a soluble GP Ibα fragment. To study thrombin binding to GP Ibα on platelets and the role of tyrosine sulfation in the process, we generated mice that express human GP Ibα either wild type (TKK) or bearing the mutation Y279F. TKK mouse platelets bound α-thrombin with an affinity similar to human platelets. Neither meizothrombin (lacking a full exosite II) nor γ-thrombin (lacking exosite I) bound to TKK platelets or human platelets. Accordingly, the exosite-specific inhibitors described above completely and independently suppressed α-thrombin binding to platelets. Mouse platelets bearing the mutation Y279F exhibited no significant thrombin binding. Since sulfated Y279 makes contacts mainly with thrombin exosite I, this can be seen as a further evidence that exosite I is involved in α-thrombin binding to platelets. Altogether, these data suggest that α-thrombin binds to platelets through a process that involves concurrently both exosites. This process is not properly reflected by the use of soluble GP Ibα fragments that can interact with thrombin solely engaging exosite II.
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46

McRae, Simon J., Alan R. Stafford, James C. Fredenburgh, and Jeffrey I. Weitz. "Studies into the Mechanism by Which Glycosaminoglycans Potentiate Protein C Activation by Factor Xa." Blood 104, no. 11 (November 16, 2004): 1724. http://dx.doi.org/10.1182/blood.v104.11.1724.1724.

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Abstract Previous studies have demonstrated that protein C (PC) can be activated by factor Xa (fXa) in a reaction that requires Ca2+ and negatively-charged phospholipid. Sulfated polysaccharides, such as heparin or dextran sulfate, have been shown to accelerate this reaction, although their mechanism of action remains elusive. To further explore this phenomenon, we first examined the effect of glycosaminoglycans of varying degrees of sulfation on the kinetics of PC activation by fXa in the presence of Ca2+ and phosphatidylcholine-phosphatidylserine vesicles (75%/25% w/w). Heparin increased the rate PC activation in a concentration-dependent and saturable fashion producing a 4-fold increase in catalytic efficiency (kcat/Km of 105 M−1 min−1) by reducing the Km for the reaction. In contrast N-desulfated heparin had no effect on the rate of this reaction, whereas dextran sulfate, which is more sulfated than heparin, increased the catalytic efficiency 21-fold. These data suggest that the capacity of glycosaminoglycans to catalyze PC activation by fXa is dependent on their degree of sulfation. The extent of sulfation is more important than chain length because hypersulfated low-molecular-weight heparin (HSLMWH) and dextran sulfate, both of which have a mean molecular weight of 5000, increased the catalytic efficiency 16- and 21-fold respectively. In contrast, enoxaparin, which also has a mean molecular weight of about 5000, had little effect. The capacity of heparin to enhance PC activation by fXa is similar in the presence of factor Va as it is in its absence, suggesting that heparin can accelerate this reaction even when fXa is incorporated within the prothrombinase complex. To begin to explore the mechanism by which these glycosaminoglycans enhance PC activation by fXa, we measured their affinities for PC and fXa, both of which have heparin-binding domains, in the presence of Ca2+. This was performed by monitoring changes in extrinsic fluorescence of fluorescein-labeled fXa or PC after addition of glycosaminoglycan. Heparin binds PC with similar affinity in the absence or presence of negatively-charged phospholipid (Kd values of 1.9 and 1.0 mM, respectively). In contrast, heparin binds fXa with 86-fold higher affinity in the presence of phospholipid vesicles than in its absence (Kd values of.007 and 0.61 mM, respectively). These findings suggest that fXa binding to phospholipid exposes a high-affinity heparin-binding site. In the absence of phospholipid, more sulfated glycosaminoglycans (dextran sulfate and HSLMWH) bind fXa with 2- to 3-fold higher affinity than heparin. These compounds exhibit a smaller increase in affinity for PC. These observations suggest that the capacity of glycosaminoglycans to enhance PC activation is dependent on the extent of sulfation, a feature that determines their affinity for fXa. How glycosaminoglycan binding to fXa modulates this reaction is uncertain, but it is more likely to reflect conformational changes in the enzyme than bridging of the enzyme to the substrate.
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47

Bistrup, Annette, Sunil Bhakta, Jin Kyu Lee, Yevgeniy Y. Belov, Michael Dee Gunn, Feng-Rong Zuo, Chiao-Chain Huang, Reiji Kannagi, Steven D. Rosen, and Stefan Hemmerich. "Sulfotransferases of Two Specificities Function in the Reconstitution of High Endothelial Cell Ligands for L-selectin." Journal of Cell Biology 145, no. 4 (May 17, 1999): 899–910. http://dx.doi.org/10.1083/jcb.145.4.899.

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L-selectin, a lectin-like receptor, mediates rolling of lymphocytes on high endothelial venules (HEVs) in secondary lymphoid organs by interacting with HEV ligands. These ligands consist of a complex of sialomucins, candidates for which are glycosylation- dependent cell adhesion molecule 1 (GlyCAM-1), CD34, and podocalyxin. The ligands must be sialylated, fucosylated, and sulfated for optimal recognition by L-selectin. Our previous structural characterization of GlyCAM-1 has demonstrated two sulfation modifications, Gal-6-sulfate and GlcNAc-6-sulfate in the context of sialyl Lewis x. We now report the cloning of a Gal-6-sulfotransferase and a GlcNAc-6-sulfotransferase, which can modify GlyCAM-1 and CD34. The Gal-6-sulfotransferase shows a wide tissue distribution. In contrast, the GlcNAc-6-sulfotransferase is highly restricted to HEVs, as revealed by Northern analysis and in situ hybridization. Expression of either enzyme in Chinese hamster ovary cells, along with CD34 and fucosyltransferase VII, results in ligand activity, as detected by binding of an L-selectin/IgM chimera. When coexpressed, the two sulfotransferases synergize to produce strongly enhanced chimera binding.
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48

Zarpellon, Alessandro, Reha Celikel, Richard McClintock, James R. Roberts, G. Loredana Mendolicchio, Hua Jing, Kottayil I. Varughese, and Zaverio M. Ruggeri. "Structural and Functional Evidence on the Role of Sulfated Tyrosine Residues In Glycoprotein Ib Binding to α-Thrombin Exosites." Blood 116, no. 21 (November 19, 2010): 326. http://dx.doi.org/10.1182/blood.v116.21.326.326.

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Abstract Abstract 326 In spite of two known crystal structures, the mechanisms supporting the interaction between the amino terminal domain of glycoprotein (GP) Ibα (GPIb-N) and α-thrombin (FIIa) are still debated, and a controversial issue concerns the involvement of FIIa exosites I and II in binding. Competition for exosite I could influence processes important for hemostasis and thrombosis. Both known crystal structures show two independent contact interfaces between GPIb-N and bound FIIa in a conformation that involves each exosite interacting with a different GPIb-N molecule. This notwithstanding, a majority of investigators in the field has concluded that exosite II is solely required for FIIa binding to GPIb-N, suggesting that the interface with exosite I is the consequence of crystal packing. The goal of this work was to probe experimentally the role of FIIa exosites in GPIb-N binding. Human GPIb-N contains three Tyr residues (at positions 276, 278 and 279) that can undergo post-translational sulfation (sulfated Tyr = Tys), although this was not the case for Tyr278 in the known crystal structures. To address this discrepancy, we expressed GPIb-N in Drosophila cells - which endogenously contain a single tyrosylprotein sulfotransferase (TPST) gene - co-transfected with human TPST-2, and showed that we could obtain different GPIb-N species with 0 to 3 sulfate moles/protein moles. Using these different GPIb-N forms immobilized onto a surface plasmon resonance (SPR) chip, we determined that the kD of human FIIa binding decreased from 1290 to 89 nM going from 0 to 3 sulfate moles/protein moles. We crystallized the fully sulfated GPIb-N complexed with FIIa and found that Tys278 established contacts not previously seen with exosite II (residues Arg35 and Lys236), thus explaining the contribution of full sulfation to maximal binding efficiency. To establish the effect of TPST-2 on the process of sulfation, we compared the affinity of FIIa binding to distinct wild type GPIb-N species of known sulfate content with that to GPIb-N mutants containing distinct single, double or triple Tyr “Phe substitutions (Phe differs from Tyr for the lack of an OH group and cannot be sulfated) in which the identity of Tys residues could be established. We found that TPST-2 favors Tyr sulfation in the order 276–278-279, which is more efficient for a complete process than the order 276–279 predominant in the absence of TPST-2. We then used different Tyr "Phe (Y to F) mutants to evaluate the effects of the substitution preventing sulfation on FIIa binding to GPIb-N in solution or immobilized onto a SPR chip. We fount that the Y276F mutant had no capacity to form a soluble complex with FIIa, while Y279F could complex about as much FIIa as fully sulfated wild type GPIb-N (82 vs 99% FIIa incorporation). Of note, both Y276F and Y279F mutants had a complete to nearly complete loss of FIIa binding activity in the SPR system. In the crystal structure, the sulfate group on Tys279 establishes three close contacts (3.1, 3.3, 2.8 □) with Trp148 in a FIIa loop neighboring exosite I. On the other hand, Tys276 has closer contacts than Tys279 with residues in exosite II, suggesting that the latter may be sufficient for FIIa binding when GPIb-N is in solution but not immobilized onto a surface. To confirm this hypothesis, we used specific aptamer inhibitors of FIIa exosite II (HD22) or I (HD1) and found that the latter, similar to the Y279F substitution, indeed had no effect on FIIa-GPIb-N soluble complex formation (thus ruling out possible allosteric effects on exosite II influencing GPIb-N binding) but completely prevented FIIa binding to immobilized GPIb-N. Of note, as shown by crystallographic evidence, bound HD1 alters the orientation of Trp148 in manner that would oppose the interaction with Tys279 in GPIb-N, providing a structural explanation for the similar functional effects of the mutation and the inhibitor. Finally, we expressed transgenically wild type or Y279F mutant human GPIbα to replace the homologous chain in the GPIb-IX-V complex of murine platelets and showed that the mutation almost completely impairs FIIa binding to platelets, which is also prevented by inhibition of exosite I with HD1. These results provide functional evidence and a structural explanation for a key role of exosite I, concurrently with exosite II, for FIIa binding to GPIbα. Additional studies are now demonstrating that interfering with this interaction modifies responses to vascular injury in vivo. Disclosures: No relevant conflicts of interest to declare.
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49

Ishihara, Masayuki, Shingo Nakamura, Yoko Sato, Tomohiro Takayama, Koichi Fukuda, Masanori Fujita, Kaoru Murakami, and Hidetaka Yokoe. "Heparinoid Complex-Based Heparin-Binding Cytokines and Cell Delivery Carriers." Molecules 24, no. 24 (December 17, 2019): 4630. http://dx.doi.org/10.3390/molecules24244630.

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Heparinoid is the generic term that is used for heparin, heparan sulfate (HS), and heparin-like molecules of animal or plant origin and synthetic derivatives of sulfated polysaccharides. Various biological activities of heparin/HS are attributed to their specific interaction and regulation with various heparin-binding cytokines, antithrombin (AT), and extracellular matrix (ECM) biomolecules. Specific domains with distinct saccharide sequences in heparin/HS mediate these interactions are mediated and require different highly sulfated saccharide sequences with different combinations of sulfated groups. Multivalent and cluster effects of the specific sulfated sequences in heparinoids are also important factors that control their interactions and biological activities. This review provides an overview of heparinoid-based biomaterials that offer novel means of engineering of various heparin-binding cytokine-delivery systems for biomedical applications and it focuses on our original studies on non-anticoagulant heparin-carrying polystyrene (NAC-HCPS) and polyelectrolyte complex-nano/microparticles (N/MPs), in addition to heparin-coating devices.
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50

Zhao, Tingting, Xiaoguang Lu, Neal M. Davies, Yuewen Gong, Jingzhen Guo, Haojun Zhang, Zhiguo Li, Jing Hong, Guixiang Fu, and Ping Li. "Diabetes Results in Structural Alteration of Chondroitin Sulfate in the Urine." Journal of Pharmacy & Pharmaceutical Sciences 16, no. 3 (July 30, 2013): 486. http://dx.doi.org/10.18433/j3gs3c.

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Purpose. The assessment of the clinical significance of chondroitin sulfate in patients with type 2 diabetes mellitus (T2DM) and diabetic nephropathy (DN) for the detection of the relationship between chondroitin sulfate (CS) structure and disease. Methods. Healthy control (n=15), type 2 diabetic patients with normalbuminuria (n=12), and patients with microalbuminuria (n=13) were enrolled in the study. Total sulfated glycosaminoglycans (GAGs) concentration in the first morning urine was evaluated by 1,9-dimethylmethylene blue method and the composition was determined by agarose gel electrophoresis. Urinary chondroitin sulfate was quantified by a combination of treatment with specific lyase digestions and separation of products by SAX-HPLC. Results: GAGs concentration significantly increased in diabetic patients with microalbuminuria compared to diabetic patients with normalbuminuria. Qualitative analysis of urinary GAGs revealed the presence of chondroitin sulfate, heparan sulfate, and low-sulphated chondroitin sulphate-protein complex (LSC-PG). There was a decrease in CS and an increase in LSC-PG in the urine of patients with diabetes compared to healthy controls. Moreover, in diabetic patients, chondroitin sulfate contains more 6-sulfated disaccharide and less 4-sulfated disaccharide. There was a statistically significant difference in ratio of 6-sulfated disaccharide to 4-sulfated disaccharide among the three groups. Conclusions: GAGs were significantly increased in diabetic patients with microalbuminuria. The levels of urinary GAGs, ratio of LSC-PG/CS, as well as ratio of 6-sulfated to 4-sulfated disaccharides could be useful markers for diagnosis of patients with diabetic nephropathy. This article is open to POST-PUBLICATION REVIEW. Registered readers (see “For Readers”) may comment by clicking on ABSTRACT on the issue’s contents page.
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