Search results for "glucosa"

ChemInform Abstract: Synthetic O-Glycopeptides as Model Substrates for Glycosyltransferases.

2010

Abstract A new approach to O-glycopeptides of the glucosamine type is described. N-Urethane protected, peracetylated glucosamine is converted into its 1-thio (1-bromo) derivative and used for glycosylation of a variety of protected serine or threonine derivatives as acceptors. The urethane group is easily exchanged for the natural N-acetyl moiety and O-deacetylation is achieved with hydrazine/methanol. The resulting O-GlcNAc derivatives are subjected to an enzymatic galactosylation procedure using β-1,4-galactosyltransferase (EC 2.4.1.22) to furnish O-glycopeptides of the neolactosamine type.

Candida albicans mycelial wall structure: supramolecular complexes released by zymolyase, chitinase and beta-mercaptoethanol.

1991

Different techniques released from the wall of Candida albicans mycelial cells high molecular weight mannoprotein materials with different levels of complexity. SDS solubilized among others one protein of 180 kDa which reacted with a monoclonal antibody (MAb) specific of a O-glycosylated protein secreted by regenerating mycelial protoplasts [Elorza et al. (1989) Biochem Biophys Res Commun 162:1118-1125]. Zymolyase, chitinase and beta-mercaptoethanol, released different types of high molecular highly polydisperse mannoprotein materials (greater than 180 kDa) that also reacted with the same MAb. These materials had N-glycosidically linked sugar chains, in addition to the O-glycosidically bond…

2016

Abstract. Bioaerosols pose risks to human health and agriculture and may influence the evolution of mixed-phase clouds and the hydrological cycle on local and regional scales. The availability and reliability of methods and data on the abundance and properties of atmospheric bioaerosols, however, are rather limited. Here we analyze and compare data from different real-time ultraviolet laser/light-induced fluorescence (UV-LIF) instruments with results from a culture-based spore sampler and offline molecular tracers for airborne fungal spores in a semi-arid forest in the southern Rocky Mountains of Colorado. Commercial UV-APS (ultraviolet aerodynamic particle sizer) and WIBS-3 (wideband integ…

Quantitative studies of the secretion of complement component C3 by resident, elicited and activated macrophages. Comparison with C2, C4 and lysosoma…

1982

To quantitate the secretion of complement component C3 by guinea pig peritoneal macrophages an enzyme-linked immunosorbent assay was developed. C3 secretion was studied in resident, elicited and activated macrophages and compared with release of hemolytically active C2 and C4, as well as the lysosomal enzyme β-D-2-acetamido-2-deoxyglucosidase. Resident macrophages secreted about 6 ng C3/106 cells/h into culture supernatants over a period of 12 h. Corynebacterium parvum-activated cells were found to secrete 3 times that amount at nearly constant rates. There was a stepwise increase in secretion of functional C2 and C4 when comparing resident, elicited and activated macrophages; secretion was…

A Combination of Celecoxib and Glucosamine Sulfate Has Anti-Inflammatory and Chondroprotective Effects: Results from an In Vitro Study on Human Osteo…

2021

This study investigated the possible anti-inflammatory and chondroprotective effects of a combination of celecoxib and prescription-grade glucosamine sulfate (GS) in human osteoarthritic (OA) chondrocytes and their possible mechanism of action. Chondrocytes were treated with celecoxib (1.85 µM) and GS (9 µM), alone or in combination with IL-1β (10 ng/mL) and a specific nuclear factor (NF)-κB inhibitor (BAY-11-7082, 1 µM). Gene expression and release of some pro-inflammatory mediators, metalloproteinases (MMPs), and type II collagen (Col2a1) were evaluated by qRT-PCR and ELISA

Unique Microbial Catabolic Pathway for the Human Core N-Glycan Constituent Fucosyl-α-1,6-N-Acetylglucosamine-Asparagine

2020

The survival of commensal bacteria in the human gut partially depends on their ability to metabolize host-derived molecules. The use of the glycosidic moiety of N-glycoproteins by bacteria has been reported, but the role of N-glycopeptides or glycoamino acids as the substrates for bacterial growth has not been evaluated. We have identified in Lactobacillus casei strain BL23 a gene cluster (alf-2) involved in the catabolism of the glycoamino acid fucosyl-α-1,6-N-GlcNAc-Asn (6′FN-Asn), a constituent of the core-fucosylated structures of mammalian N-glycoproteins. The cluster consists of the genes alfHC, encoding a major facilitator superfamily (MFS) permease and the α-l-fucosidase AlfC, and t…

Structural determination of the lipo-chitin oligosaccharide nodulation signals produced by Rhizobium giardinii bv. giardinii H152

2003

Abstract Rhizobium giardinii bv. giardinii is a microsymbiont of plants of the genus Phaseolus and produces extracellular signal molecules that are able to induce deformation of root hairs and nodule organogenesis. We report here the structures of seven lipochitooligosaccharide (LCO) signal molecules secreted by R. giardinii bv. giardinii H152. Six of them are pentamers of GlcNAc carrying C 16:0 , C 18:0 , C 20:0 and C 18:1 fatty acyl chains on the non-reducing terminal residue. Four are sulfated at C-6 of the reducing terminal residue and one is acetylated in the same position. Six of them are N -methylated on the non-reducing GlcN residue and all the nodulation factors are carbamoylated o…

Disulfide-crosslinked hyaluronan-gelatin hydrogel films: a covalent mimic of the extracellular matrix for in vitro cell growth

2003

A new disulfide crosslinking method was developed for the preparation of blended hyaluronan (HA)-gelatin hydrogels to form a synthetic, covalently linked mimic of the extracellular matrix (ECM). The HA and gelatin were chemically modified using 3,3′-dithiobis(propionic hydrazide) (DTP). After reduction with dithiothreitol (DTT), the thiol derivatives of HA (HA-DTPH) and gelatin (gelatin-DTPH) were obtained and characterized. To minimize interference with biological function, the degree of substitution of HA-DTPH and gelatin-DTPH was kept below 50%. Solutions of HA-DTPH and gelatin-DTPH in varying blends (20%, 40%, 60%, 80% gelatin) were prepared in 1% w/v NaCl and crosslinked by disulfide b…

Transient Receptor Potential Canonical 3 (TRPC3) Channels Are Required for Hypothalamic Glucose Detection and Energy Homeostasis

2017

Fil: Chrétien, Chloé. University of Bourgogne Franche-Comté. Institut National de la Recherche Agronomique. Centre des Sciences du Goût et de l’Alimentation; France Fil: Fenech, Claire. University of Bourgogne Franche-Comté. Institut National de la Recherche Agronomique. Centre des Sciences du Goût et de l’Alimentation; France Fil: Liénard, Fabienne. University of Bourgogne Franche-Comté. Institut National de la Recherche Agronomique. Centre des Sciences du Goût et de l’Alimentation; France Fil: Grall, Sylvie. University of Bourgogne Franche-Comté. Institut National de la Recherche Agronomique. Centre des Sciences du Goût et de l’Alimentation; France Fil: Chevalier, Charlène. University of …

Glucosamine Supplementation Improves Physical Performance in Trained Mice

2021

Introduction D-Glucosamine (GlcN) is one of the most widely consumed dietary supplements and complementary medicines in the world and has been traditionally used to attenuate osteoarthritis in humans. GlcN extends lifespan in different animal models. In humans, its supplementation has been strongly associated with decreased total mortality and improved vascular endothelial function. GlcN acts as a suppressor of inflammation and by inhibiting glycolysis, it can activate the metabolism of stored fat and mitochondrial respiration. Methods The conventional human GlcN dose is 1,500 mg x day-1 but extensive evidence indicates that much higher doses are well tolerated. GlcN is one of the supplemen…