Просмотр исходного текста страницы Heparin-Heparan-Sulfate-Oligosaccharides-Studies-Synthesis-Means-p

The various synthetic strategies available to chemical synthesis have recently enabled the acquisition of several regular and irregular sequences, including a number of dodecasaccharides, through improved coupling methods and judicial protecting group manipulations. Controlled chain elongation and critical application of modification enzymes allowed the generation of well-defined constructs via chemoenzymatic synthesis. Investigations of various protein interactions with the synthetic constructs delivered valuable information that could aid future drug development endeavors.Conformational analysis of furanoside-containing mono- and oligosaccharides.Structure elucidation of a novel acidic tetrasaccharide and hexasaccharide derived from a chemically modified heparin.Oligosaccharins--oligosaccharides that regulate growth, development and defence Darvill A(1), Augur C, Bergmann C, Carlson RW, Cheong JJ, Eberhard S, Hahn MG, Quantitative recovery of Man9GlcNAc2Asn derivatives from concanavalin A.<br /><br />Some larger high-mannose-type oligosaccharides bind very tightly to concanavalin A and are difficult to elute. We present conditions that permit the complete elution of compounds containing high-mannose type oligosaccharides from a popular concanavalin A-Sepharose that is commercially available. [https://en.wikipedia.org/wiki/Lacto-N-tetraose Fucosylated oligosaccharides] -labeled Man9GlcNAc2Asn (N. Kawasaki and Y.C. Lee, Anal. Biochem.<br /><br />, [http://www.allinno.com/product/healthcare/674.html Human Milk Glycans] bound to concanavalin A-Sepharose were completely eluted with 1 M methyl alpha-D-mannopyranoside by allowing the column to stand in elution buffer, permitting the oligosaccharide or glycoprotein to slowly dissociate from the Prompt chemoenzymatic synthesis of diverse complex-type oligosaccharides and its application to the solid-phase synthesis of a glycopeptide with Asn-linked sialyl-undeca- and asialo-nonasaccharides.We describe herein the preparation of 24 pure asparagine-linked oligosaccharides [(NeuAc-alpha-2,6-Gal-beta-1,4-GlcNAc-beta-1,2-Man-alpha-1,61,3-)(2)-Man-beta-1,4-GlcNAc-beta-1,4-GlcNAc-beta-1-asparagine, 2] obtained from egg yolk. Our synthetic strategy aimed at adapting branch specific exo-glycosidases digestion (beta-D-galactosidase, N-acetyl-beta-D-glucosaminidase and alpha-D-mannosidase) of the individual asialo-branch after preparation of monosialyloligosaccharides obtained from 2 by acid hydrolysis of NeuAc. In order to perform branch specific exo-glycosidase digestion, isolation of pure monosialyloligosaccharides obtained was essential. However, isolation of two kinds of monosialyloligosaccharides are difficult by HPLC due to their highly hydrophilic nature. Therefore, we examined chemical protection with hydrophobic protecting (Fmoc and benzyl) groups. These chemical protection enabled us to separate the monosialyloligosaccharides by use of a HPLC column (ODS) on synthetic scales.<br /><br /> Using these pure monosialiloligosaccharides enable us to obtain 24 Asn-linked oligosaccharides and alpha-D-mannosidase). In addition, solid-phase synthesis of glycopeptide having Asn-linked sialyl-undeca- and asialo-nonasaccharides thus obtained, was also performed on an acid labile HMPA-PEGA resin.Teratogenic effects induced by chitosan oligosaccharide in Wistar female rat The aim of this research is to investigate the teratogenic effects of chitosan oligosaccharide in Wistar female rats (Rattus norvegicus). Chitosan LD value was calculated by probit analysis. High dose, 1 LD which equal to 1&nbsp;mgkg body weight, and low dose, 1 LD which equal to &nbsp;mgkg body weight, were administrated orally to Wistar female rats to examine the teratogenic effect during organogenesis period from 6th day to 15th day of gestation. Treated and control rats were sacrificed and their foetuses were examined for external, skeletal and visceral anomalies, number and length of foetuses and their weights. Obtained results showed toxicity and teratogenic effects of chitosan on treated rats and their progenies, i.<br /><br />e. high fetal mortality, offspring's weight and length reduction, and high incidence of fetal external, skeletal and visceral abnormalities. This suggested that chitosan is a teratogenic compound, restricted to current results from orally treated Wistar rats.Core sugar residues of the N-linked oligosaccharides of Russell's viper venom factor X-activator maintain functionally active polypeptide structure.We have previously showed that factor X activator of Russell's viper venom and one in each of the two light chains [Gowda, D.C., Jackson, C.<br /><br />M., Hensley, P., &amp; Davidson, E.A. (1994) J. Biol. Chem.<br /><br /> 269, 644-6]. In the present study, we have investigated the role of the carbohydrate moieties in the structure and functional activity of RVV-X.