Presence-Fluorine-Atoms-Effects-Cells-b

Moreover, the number of fluorine atoms did not pose a steric barrier and instead, their presence possibly increased the hydrophobicity of the primer and enhanced membrane permeability. This strategy of using a fluorous-tagged primer and cells can pave the way for an easier way of preparing oligosaccharides via an environment-friendly approach that eliminates the use of large amounts of Induction of anti-pneumococcal cell wall polysaccharide antibodies by type 4 pneumococcal polysaccharide-protein conjugates.Wilhelmina Kinderziekenhuis, State University, School of Medicine, Utrecht, The We have prepared polysaccharide-protein conjugates consisting of type 4 pneumococcal capsular polysaccharide (PS4) coupled to tetanus toxoid. The PS4 preparation used contained 2% pneumococcal cell wall polysaccharide (CPs). During the conjugation process, in addition to PS4-protein conjugates, CPs-protein conjugates were also formed. After immunization with PS4-protein conjugates, CPs-protein conjugates that are present as a contaminant induce IgG anti-CPs antibodies in mice.

Pneumococcal oligosaccharides, prepared by periodate oxidation of PS4, did not contain detectable amounts of CPs; hence, oligosaccharide-protein conjugates did not induce anti-CPs antibodies.The cell wall polymer of the extremely halophilic archaeon Natronococcus The cell wall polymer of Natronococcus occultus (DSM 3396) consists of L-glutamate, N-acetyl-D-glucosamine, N-acetyl-D-galactosamine, D-galacturonic acid, D-glucuronic acid and D-glucose in a molar ratio of 5718. Partial acid hydrolysis of the cell wall polymer produced soluble fragments that could be separated by HPLC. A gamma-glutamyl dipeptide was isolated. In the intact cell wall polymer, the glutamate residues form a poly-(gamma-glutamine) chain with a length of about monomers, which corresponds to a relative molecular mass of approximately 70 Da. Two other soluble dimeric fragments, composed of glutamate and either glucosamine or galactosamine in a molar ratio of 11, were purified from the hydrolysate, suggesting the presence of two different oligosaccharides linked to the poly-(gamma-glutamine) chain of the intact polymer. 2'-fucosyllactose of additional fragments, which were composed of an amino sugar and galacturonic acid or glucose indicated that one oligosaccharide consisted of a glucosamine pentamer in an alpha-1,3 linkage at the reducing end and an oligomer with at least five beta-1,4-linked galacturonic acid residues at the non-reducing end.

The second oligosaccharide was comprised of a galactosamine dimer in a beta-1,3 linkage at the reducing end and a maltose unit at the non-reducing end. Both oligosaccharides were linked to the alpha-amide group of the glutamine residues of the poly-(gamma-glutamine) chain. The whole cell wall polymer, which represents a novel type of natural glycoconjugate, has Chemical synthesis of 6'-alpha-maltosyl-maltotriose, a branched oligosaccharide representing the branch point of starch.Chemical synthesis of the branched pentasaccharide 6'-alpha-maltosyl-maltotriose another synthon as a glycosyl donor. 2'-Fucose lactose used as glycosyl acceptor was phenyl 2,3,6-tri-O-benzyl-1-thio-beta-D-glucopyranoside (7) and was synthesized 2,3-di-O-acetyl-4,6-O-benzylidene-1-thio-beta-D-glucopyranoside and phenyl 2,3-di-O-benzyl-4,6-O-benzylidene-1-thio-beta-D-glucopyranoside as key intermediates. The synthon used as glycosyl donor was O-(2,3,4,6-tetra-O-benzyl-alpha-D-glucopyranosyl)-(1--4)-O-(2,3,6-tri-O -benzyl - alpha-D-glucopyranosyl)-(1--6)-O-[(2,3,4,6-tetra-O-benzyl-alpha-D- glucopyranosyl)-(1--4)]-2,3-di-O-benzyl-alpha,beta-D-glucopyranosyl trichloroacetimidate (12) and was synthesized from phenyl O-2,3,4,6-tetra-O-benzyl-alpha-D-glucopyranosyl)-(1--4)-O-(2,3,6-tri-O- benzyl- alpha-D-glucopyranosyl)-(1--6)-O-[(2,3,4,6-tetra-O-acetyl-alpha-D- glucopyranosyl)-(1--4)]-2,3-di-O-acetyl-1-thio-beta-D-glucopyranoside with O-(2,3,4,6-tetra-O-benzyl-alpha-D-glucopyranosyl)-(1--4)-O-(2,3,6-tri-O - benzyl-alpha-D-glucopyranosyl)-(1--4)]-2,3-di-O-benzyl-D-glucopyranose as an intermediate. Condensation of compounds 7 and 12 followed by removal of the phenylthio group and debenzylation provided the branched pentasaccharide 15.

Alternatively, the branched pentasaccharide was produced from amylopectin by consecutive alpha- and beta-amylase treatments and purified by chromatography. The identity of the products obtained by chemical synthesis and enzymatic hydrolysis is documented by 1H and 13C NMR spectra-N-glycyl beta-oligosaccharide derivatives as stable intermediates for the Biochemistry 1993 Apr 13;32(14)3829.Incubation of reducing sugars in ammonium bicarbonate was found to be a simple procedure for the formation of beta-D-glycosylamines of purified complex oligosaccharides in -% yield.