Chizhov-Ao-Dell-Hr-Haslam-Sm-Mcdowell-Fractions-Chorda-Desulfation-e

Methylation analysis and NMR spectroscopy were applied for native and desulfated polysaccharides. Homofucan sulfate from C. filum was shown to contain poly-alpha-(1--3)-fucopyranoside backbone with a high degree of branching, mainly of alpha-(1--2)-linked single units. Some fucopyranose residues are sulfated at O-4 (mainly) and O-2 positions. Some alpha-(1--3)-linked fucose residues were shown by NMR to be 2-O-acetylated. The 1H and 13C NMR spectra of desulfated, deacetylated fucan were completely assigned.

The spectral data obtained correspond to a quasiregular polysaccharide structure with a branched hexasaccharide repeating unit. Other fucoidan fractions from C. filum have more complex carbohydrate composition and give Solid phase disruption of fluid phase equilibrium in affinity assays with ELISA.Quantitation of antibody affinity for antigen can provide important information in assessment of the human immune response. Enzyme-linked immunosorbent assay low affinity, low titer antibody. The major assumption in using this method, that the solid phase does not influence the equilibrium of the fluid phase antibody-antigen interaction, is not strictly true. Hence, conditions must be chosen to minimize such interference, which can result in spuriously low values of affinity.

2'-fucosyllactose of solid phase interference was therefore quantitated for an ELISA that measures the affinity between antibody directed against the capsular polysaccharide of Haemophilus influenzae type b, using a monovalent 3-unit oligosaccharide prepared from polysaccharide. The solid phase antigen density had the greatest effect upon disruption of the fluid phase. The concentration of antibody chosen had a measurable but modest effect on the outcome of ELISA, whereas the time of incubation of the antibody and oligosaccharide had no demonstrable effect. By choosing the conditions of the assay carefully, it was possible to minimize interference from the solid phase, so that the measured affinity of anticapsular polysaccharide antibody for monovalent antigen was similar to that obtained with the more traditional Determination of linkage positions in peracetylated (methyl) xylo-oligosaccharides with fast atom bombardment mass spectrometry.Blok-Tip L(1), van der Kerk-van Hoof A, Heerma W, Haverkamp J, Kovácik V, Hirsch Universiteit Utrecht, The Netherlands.Distinction between the linkage types 1--2, 1--3 and 1--4 of xylobioses can be achieved on the basis of the unimolecular decomposition spectra of the oxonium ions of the per-O-acetylated methyl glycosides. The spectra of the oxonium ions of various unbranched xylotri-, tetra- and pentaoses allow determination of the linkage position between the xylose residues.

This indicates that in unbranched peracetylated xylo-oligosaccharides the linkage between the xylose residues at the non-reducing end can be determined.OB-fold growing bigger with functional consistency.It was predicted that the folding space for various protein sequences is restricted and a maximum of protein folds could be expected. Although, there were about 648 folds identified, general functional features of individual folds is not thoroughly studied. We selected OB-fold, which is supposed to be an oligonucleotide and oligosaccharide binding fold to study the general functional features. OB-fold is a small beta-barrel fold formed from 5 strands connected by modulating loops. We observed consistently 2 or 3 loops on the same face of barrel acting as clamps to bind to their ligands.

Depending on the ligand, which could be a single or double stranded DNARNA or an oligosaccharide, and their conformational properties the loops change in length and sequence to accommodate various ligands. 2'-Fucose lactose of OB-folded proteins were analyzed and found that the functional features are retained in spite of negligible sequence homology among various proteins studied.Biosynthesis of non-sulfated high-molecular-weight glycosaminoglycans and Education, Jiangnan University, Wuxi 214122, China; The Science Center for Future Foods, Jiangnan University, Wuxi 214122, China.Education, Jiangnan University, Wuxi 214122, China.Education, Jiangnan University, Wuxi 214122, China; The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Education, Jiangnan University, Wuxi 214122, China; The Science Center for Non-sulfated forms of glycosaminoglycans (NSGAGs) including hyaluronan, chondroitin and heparosan with high-molecular-weight (HMW) are extensively used biomaterials, while NSGAGs oligosaccharides display strong bioactivities.