PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “GLUCOSAMINE”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,441 records · Page 80Linked to original sources
PubMed1985

Flavobacterium heparinum 6-O-sulphatase for N-substituted glucosamine 6-O-sulphate.

A specific glyco-6-O-sulphatase has been purified to homogeneity from Flavobacterium heparinum. The enzyme hydrolyses the 6-O-sulphates of 2-deoxy-2-sulphamido-6-O-sulpho-D-glucose (GlcNS-6S), 2-acetamido-2-deoxy-6-O-sulpho-D-glucose (GlcNAc-6S) and 2-amino-2-deoxy-6-O-sulphato-D-glucose (GlcN-6S). The activity was purified 2100-fold by successive chromatography on CM-Sepharose CL-6B, Sepharose CL-4B, hydroxyapatite and blue-Sepharose CL-6B. Sodium dodecyl sulphate/polyacrylamide gel electrophoresis showed a protein of relative molecular mass 64000. Four novel assays were developed using 35S-labelled and 14C-labelled monosaccharides. The purified enzyme was free of all other known heparin-degrading enzymes. In particular this was the first resolution of the 6-O-sulphatase from the sulphamidase. Optimal activity was at pH 7.5. Enzyme activity was virtually unaffected by Na+ and K+ ions. Enhancements of activity of 12% and 30% were effected by Mg2+ and Ca2+ ions respectively. Inorganic phosphate and sulphate (both 0.005 mol dm-3) inhibited activity by 48% and 50% respectively. The Km value for the free amino substrate GlcN-6S was 1.35 mmol dm-3. In contrast the Km values for the GlcNAc-6S and GlcNS-6S were 54 mumol dm-3 and 16 mumol dm-3 respectively.

Flavobacterium↗
PubMed1989

Antiviral activity of a D-glucosamine derivative against herpetic ulcers (HSV type 2) in rabbit cornea.

Although most herpetic ocular infections in adults are caused by herpesvirus hominis type 1, several cases of culture proved HSV-2 ocular infection in adults have been described, with more severe and prolonged disease. In a screening for new antiherpetic compounds, we investigated the efficacy in vivo of a new compound, nitroderivative of D-glucosaminhydrochloride (GN-11) in comparison with D-glucosaminhydrochloride (GN), Acyclovir (ACV) and placebo against herpetic keratitis of herpes simplex type 2 in 4 x 4 eyes from 4 x 4 rabbits, respectively. ACV and GN-11 showed similar results. The treatment with GN-11 retarded the appearance of herpetic lesions, which were small and diffuse in comparison with the placebo group. A total recovery was obtained on the 12th day of the treatment. In the ACV treated group, a minimal number of small lesions appeared, but the eyes recovered normality on the 7th day of treatment. The appearance of acute herpetic keratitis was prevented by GN-11. Placebo and GN treated groups showed similar evolution, with lost vision and neurological involvement on the 7th day of infection.

Acyclovir↗
PubMed2006

Structural basis of glmS ribozyme activation by glucosamine-6-phosphate.

The glmS ribozyme is the only natural catalytic RNA known to require a small-molecule activator for catalysis. This catalytic RNA functions as a riboswitch, with activator-dependent RNA cleavage regulating glmS messenger RNA expression. We report crystal structures of the glmS ribozyme in precleavage states that are unliganded or bound to the competitive inhibitor glucose-6-phosphate and in the postcleavage state. All structures superimpose closely, revealing a remarkably rigid RNA that contains a preformed active and coenzyme-binding site. Unlike other riboswitches, the glmS ribozyme binds its activator in an open, solvent-accessible pocket. Our structures suggest that the amine group of the glmS ribozyme-bound coenzyme performs general acid-base and electrostatic catalysis.

5' Untranslated Regions↗
PubMed1987

Biological activities of chemically synthesized 2-keto-3-deoxyoctonic acid-(alpha 2----6)-D-glucosamine analogs of lipid A.

The mitogenicity, lethal toxicity, and Shwartzman reaction of three derivatives of chemically synthesized 2-keto-3-deoxyoctonic acid-linked 2,3-diacyloxyacylglucosamine-4-phosphate (KDO-GlcN-4-P) were determined. The compounds, A-301 (with di-3-hexadecanoyloxytetradecanoyl at the C-2 and C-3 positions), A-303 (di-3-tetradecanoyloxytetradecanoyl), and A-305 (3-dodecanoyloxytetradecanoyl and 3-tetradecanoyloxytetradecanoyl), induced a significant incorporation of [3H]thymidine into splenocytes of C57BL/6 mice. The compounds A-301 and A-303 showed lethality at a high dose of 50 micrograms per mouse in C57BL/6 mice sensitized with D-galactosamine, whereas A-305 caused toxicity even at a dose of 10 micrograms per mouse. However, the three compounds did not elicit the local Shwartzman reaction in rabbits. These findings indicate that the addition of 2-keto-3-deoxyoctonic acid enhances the mitogenic activity of 2,3-diacyloxyacylglucosamine-4-phosphate but does not affect the lethal toxicity and the induction of Shwartzman reaction.

Animals↗
PubMedDate not supplied

[The study of the reaction of terminated oligomerization in the synthesis of oligo-(beta1-6)-glucosamines].

The applicability of terminated oligomerization to the synthesis of oligo-(beta1-6)-glycosamines, fragments of the intercellular polysaccharide adhesin of staphylococci, was studied. The reactions of terminated oligomerization were carried out with mono-, di-, and trisaccharide monomers and N-protected aminopropanol; and spacered mono- and disaccharides as terminating molecules were also attempted. The primary formation of cyclic products of monomer intramolecular glycosylation was observed in almost all the reactions. Only the experiments with the monomer based on the disaccharide bromide under the conditions of the Helferich reaction led to reduced yields (30%) of the cyclic products. However, even in this case, the desired terminated oligosaccharides were generated in approximately 10% yield and mainly were the products of single glycosylation of the terminator by the monomer. These experiments allow the conclusion that, under the examined conditions, the reaction of terminated oligomerization could not result in the synthesis of oligoglucosamines with a high molecular mass.

Carbohydrate Sequence↗