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The structure of an intact glycosaminoglycan (GAG) chain of the bikunin proteoglycan (PG) is studied by using a combined top-down and bottom-up sequencing strategy. Electrospray ionization Fourier transform-ion cyclotron resonance mass spectrometry analysis of the size-uniform fraction of bikunin GAG mixture has determined the chain length and number of sulfo groups in the intact GAGs.

The effect of glycosaminoglycans of varying degrees of sulfation was examined on the kinetics of protein C activation by factor Xa (f.Xa) in the presence of [Ca.sup.2+] and phospahtidylcholine-phosphatidylserine vesicles (PVPS). The findings suggest that a high affinity glycosaminoglycan binding site is exposed when f.Xa binds to PCPS.

A study used ultraviolet (UV) visible spectroscopy to show that the chloramides derived from N-acetyl function of the glycosamine rings were formed by the reaction of HOCl with glycosaminoglycans and model compounds. Results indicate that selective fragmentation takes place at disaccharides intervals due to the analogous reactions with glycosaminoglycans and HOCL- mediated glycosaminoglycan fragmentation can play an important role in disease progression and resolution.

Research has been conducted on carbohydrate sulfation. The study of the sulfotransferase subtype acting on GalNAc, Gal and GlcNAc residue 6-position has been carried out and the role of carbohydrate sulfotransferases in glycosaminoglycans' inflammatory response and biosynthesis has been investigated and discussed.

Results reveal that among the glycosaminoglycans heparin binds with high affinity to the surface antigen circumsporozoite protein of malaria sporozoites. Data indicate that a decasaccharide represents the minimum sized sequence that can bind to circumsporozoite.

The regio- and stereoselective synthesis of beta-D-gluco-, alpha-L-ido- and alpha-L-altropyranosiduronic acids from delta(super 4)-uronate monosaccharides was described. The trans-diaxial bromohydrin analogues were produced by bromination of the C-4,5 double bond, and these compounds were converted to the corresponding epoxides in high yields. Direct reduction of the epoxides using borane-tetrahydrofuran system resulted in the corresponding glucuronic acids in low to moderate yields.

The binding site on the chemokine interleukin-8 (IL-8) for the glycosaminoglycan heparin was characterized through a systematic series of site-directed mutants of IL-8 in which the basic residues were replaced by alanine. Findings revealed a heparin-binding surface on IL-8 that includes the C-terminal alpha-helix and the proximal loop around residues 18-23. The heparin-binding site is spatially differentiated from the residues having to do with receptor binding.

A study was conducted to test whether pigment epithelium-derived factor (PEDF) associates with the bovine interphotoreceptor matrix by ionic interactions. Chemical modification, limited proteolysis and a predictive spatial framework were utilized to determine a glycosaminoglycan-binding region on the amino acid sequence of the PEDF. Results indicated that PEDF does not support a homology with antithrombin III in basic residues at helix D.

A study was conducted on the interaction between glycosaminoglycans and amyloid-associated immunoglobulin light chains using size-exclusion high-performance liquid chromatography and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The findings show that heparin 16,000 and chondroitin sulfate B and C precipitated both human intact light chains and recombinant light chain variable domains. The strongest interactions were observed with proteins that had formed amyloid.

The binding of the long platelet-derived growth factor A (PDGF-A) isoform to a heparin, a glycosaminoglycan, was studied. To this end, the rA125 and the rA109 variants of PDGF-A were expressed in Escherichia coli and characterized using surface plasmon resonance. The results revealed the high affinity binding of the long homo dimer, rA125, to low molecular weight heparin. This was attributed to the presence of an amino acid carboxyl-terminal extension that is absent in the short homodimer.

A model based on an X-ray crystal structure of Congo Red described the sulfonated azo dye's active site binding with the HIV-1 protease. Model behavior indicated a higher affinity for the Evans Blue dye compared to Congo Red. Analysis of the interactions involving sulfonate and sulfate groups with functional groups in protein yielded six complexes that were formed by the activity between an amino acid and a sulfonated azo dye.

1H and 13C NMR spectroscopy are used to investigate the interaction of histamine with beef lung heparin. Results reveal that histamine is bound by heparin in an intensely pD-dependent manner. At low pD, some histamine binds territorially in the condensation volume around heparin. At increasing pD and as the carboxylic group is titrated, a binding region with a high affinity for the imidazolium ring is generated. NMR results also indicate the presence of a binding site with a high attraction for the imidazolium ring.

A comparison of the crystal structure of human artemin (ART) and previously solved glial cell-line derived neurotrophic factor (GDNF) structure is presented, where the structure contains three sulfate anions that are arranged in a triad motif and are suggestive of a glycosaminoglycan (GAG)-binding site. The ART is suggested to bind HSPGs and identify residues that may be involved in HSPG binding.

A novel method, which explains the synthesis of glycosaminoglycan using a transition state analogue monomer, is reported. The glycosaminoglycan used in the study is hyaluronan, which is a natural polysacharide.

The purpose of this work is to analyze glycosaminoglycans (GAGs) directly from complex mixtures without the need to purify individual components. Novel conditions for negative ion electrospray MS of chondroitin sulfate (CS) oligosaccharides are described in which sodium adduction and fragmentation are avoided. Differentiation between positional sulfation isomers is demonstrated for CS disaccharides, and a selected reaction monitoring scheme is used to quantify sulfation isomers in disaccharides liberated from decorin and biglycan. A size exclusion chromatography LC/MS method is shown to be effective for compositional analysis of longer CS oligosaccharides. The SEC step serves to simplify the composition of GAGs entering the mass spectrometer at any time, thus allowing the masses of the constituent molecules to be extracted. Mass spectrometric detection produces far more information than conventional UV or fluorescent detectors and allows the monosaccharide composition of individual components to be determined.

Chemokines are known to be actively involved in the mediation of cellular recruitment in routine immunosurveillance and inflammation. Being a family of proteins that interact with cell surface glycosaminoglycans (GAGs), chemokines help to drive the formation of haptotactic gradients at the site of an inflammation. The selectivity of this chemokine-GAG interactions suggests that a disruption of the immobilized gradient may be an achievable therapeutic approach in inflammatory disease.

An evaluation of the search capabilities of three widely used programs, namely, GRID, DOCK and AutoDock, for heparin binding sites was conducted using known crystal structures of the protein-heparin complexes antithrombin, and acidic and basic fibroblast growth factor. The heparin binding site for all test cases was correctly determined with all three programs. When the protocols were used to predict the heparin binding site on Interleukin-8 (IL-8), results suggested that His18, Lys20, Arg60, Lys64 and Arg68 in IL-8 all bind to heparin.