Identification of a capsular polysaccharide from Moraxella bovis

Component Causes of Infectious Bovine Keratoconjunctivitis - The Role of Moraxella Species in the Epidemiology of Infectious Bovine Keratoconjunctivitis

Infectious bovine keratoconjunctivitis (IBK) involves multiple factors and opportunistic pathogens, including members of the genus Moraxella, specifically M bovis. The causal role of M bovis is clear, where the presence of virulence factors that facilitate colonization (pili) and host cytotoxicity (RTX toxins) are well characterized, and IBK has been reproduced in many models. Experimental infection with M bovoculi has failed to reproduce IBK-typical lesions in cattle thus far. However, recent work using genomics and mass spectrometry have found genomic diversity and recombination within these species, making species differentiation complex and challenging the ability to assign IBK causality to these organisms.

Structure characterization, antioxidant and emulsifying capacities of exopolysaccharide derived from Pantoea alhagi NX-11

Pantoea alhagi exopolysaccharides (PAPS) have been shown to enhance crop resistance to abiotic stress. However, physicochemical properties and structure of PAPS have not yet been analyzed. In this study, two PAPSs, named PAPS1 and PAPS2, were isolated and purified from the P. alhagi NX-11. The results showed PAPS1 and PAPS2 were composed of glucose, galactose, glucuronic acid, glucosamine and mannose with average molecular weight of 1.326 × 10⁶ Da and 1.959 × 10⁶ Da, respectively. Moreover, the structure of PAPS1 and PAPS2 was investigated by FT-IR and NMR analysis. PAPS1 was identified to have the backbone structure of →4)-β-D-GlcpA-(1→2)-α-D-Galp-(1→3)-β-D-Galp-(1→3)-β-D-GlcpN- (1→3)-α-D-Galp-(1→3)-β-D-Galp-(1→. PAPS2 had the backbone structure of →4)-β-D-GlcpA-(1→2)-α-D-Galp-(1→3)-β-D-Glcp-(1→3)-β-D-GlcpN-(1→3)-α-D-Galp-(1→3)-α-D-GlcpN-(1→. In addition, PAPS1 and PAPS2 had moderate antioxidant and emulsifying capacities. Overall, the structure analysis of PAPS may point out the direction for the subsequent study of PAPS-mediated microbial and plant interactions, and further exploration of the application of PAPS.

Chemoenzymatic synthesis of homogeneous chondroitin polymers and its derivatives

Chondroitin sulfate is a linear glycosaminoglycan widely distributed as an important extracellular matrix component of mammalian cells. It participates in numerous pathological processes, however, illustration of its diverse biological roles is hampered by the unavailability of structurally defined chondroitin polymers and their derivatives. Herein, we report a novel homogeneous chondroitin polymers synthetic strategy which combines stepwise oligosaccharides synthesis with one-pot homogeneous chondroitin chain polymerization. Exogenous trisaccharide was proved to be the necessary acceptor for PmCS-catalyzed homogeneous chondroitin polymers synthetic reactions. The strategy exhibited a well-controlled relationship between the final sugar chain length and the molar ratios of reaction substrates that could synthesize homogenous chondroitin polymers with unprecedented narrow molecular weight distribution. More importantly, the strategy was further expanded to synthesis of unnatural zwitterionic and N-sulfonated chondroitin polymers by incorporation of sugar nucleotide derivatives into the synthetic approach.

Immunomodulatory properties of Trehala manna decoction and its isolated carbohydrate macromolecules

ETHNOPHARMACOLOGICAL RELEVANCE

Trehala manna (Shekar tighal) is a cocoon-shaped manna produced by larval activity of Curculionidae family on some Echinops species. In Persian traditional medicine, it is used not only for the treatment of fever and constipation but also for sore throat, influenza and some other viral and bacterial infections which seems to be related to its boosting effects on immune system. The aim of this study was to evaluate immunomodulatory properties of Trehala manna and its isolated polysaccharides.

MATERIALS AND METHODS

Several carbohydrate macromolecules were isolated from Trehala manna decoction using solvent-solvent extraction, ion exchange and size-exclusion chromatography. The macromolecules were characterized by gas chromatography-mass spectrometry and spectrophotometric methods. The immunomodulatory effects of Trehala manna decoction and its isolated polysaccharides were evaluated on Jurkat cells at different concentrations using WST-1 reagent.

RESULTS

Seven water-soluble polysaccharides were isolated with the structures of rhamnogalacturonan, glucogalacturonan, manno-arabinogalacturonan or homogalacturonan and the molecular weights (MW) of ≤1.67-667 ≤ kDa. Large polysaccharides with MW ≥667 kDa and pectin inhibited the proliferation of Jurkat cells in a dose-dependent manner with the IC50 range of 98.06-429.53 µg/mL. The IC50 for low MW polysaccharides (around 1 kDa) did not show considerable cytotoxicity (IC50>1000 µg/mL), in contrast, they exhibited a dose-dependent enhancement of cell proliferation at concentration range of 15.62-62.50 μg/mL.

CONCLUSION

Trehala aqueous decoction and its isolated polysaccharides showed some immunomodulatory effects on Jurkat cell line in a dose-dependent manner and the molecular weight of these polysaccharides also revealed a great impact on their cytotoxic/proliferative properties.

Analysis of carbohydrates and glycoconjugates by matrix-assisted laser desorption/ionization mass spectrometry: an update for the period 2005-2006

This review is the fourth update of the original review, published in 1999, on the application of MALDI mass spectrometry to the analysis of carbohydrates and glycoconjugates and brings coverage of the literature to the end of 2006. The review covers fundamental studies, fragmentation of carbohydrate ions, method developments, and applications of the technique to the analysis of different types of carbohydrate. Specific compound classes that are covered include carbohydrate polymers from plants, N- and O-linked glycans from glycoproteins, glycated proteins, glycolipids from bacteria, glycosides, and various other natural products. There is a short section on the use of MALDI-TOF mass spectrometry for the study of enzymes involved in glycan processing, a section on industrial processes, particularly the development of biopharmaceuticals and a section on the use of MALDI-MS to monitor products of chemical synthesis of carbohydrates. Large carbohydrate-protein complexes and glycodendrimers are highlighted in this final section.