Understanding the mechanisms of biological processes requires accurate knowledge of the three-dimensional structures of the executing molecules, eg, proteins, bioactive peptides, and others. For this, we have determined the three-dimensional structures of de novo designed and natural anti-microbial and anti-endotoxic peptides in complex with lipopolysaccharide (LPS), the main component of the outer membrane of gram-negative bacteria using solid-state NMR methods. solution. . Center for Nanoscience and Molecular Medicine, Amrita Institute of Medical Sciences and Research Centre, AIMS-Ponekkarra, Edapally, Cochin, Kerala-682041.
TA is a phosphodiester polymer that is ubiquitous in Gram-positive bacteria and constitutes 50% of the mass of the bacterial cell wall. Preincubation of human epithelial cells with isolated WTA resulted in a decrease in the adhesion of wild-type cells to human epithelial cell lines.
Research led UG education at IISER Pune K.N. Ganesh
Cell wall polysaccharides of plant fibers: biosynthesis and functional role Tatyana A. Gorshkova
The chemical synthesis of oligosaccharides often involves a glycosylation reaction between a glycosyl donor and an aglycone. A new glycosyl donor to this repertoire was introduced by exploiting gold catalysts on stable propargyl glycosides from our laboratory. Many advantages are provided as propargyl glycosides are frequently synthesized via acid-mediated Fisher glycosylation conditions and they are stable to most of the frequent reactions in carbohydrate chemistry.
Already recently, while investigating the reactivity of propargyl glycosides for the synthesis of immunological epitopes of infectious bacteria, we observed the formation of 1,6-anhydro monosaccharides that were envisaged to originate from the aglycone as a result of the activation of the methyl glycosides. Also, it is pertinent to mention that gold-mediated activation of propargyl glycosides is orthogonal to some of the already reported glycosyl donors.
Monosaccharide Modifications and Studies on Lipoarabinomannan Oligosaccharides N. Jayaraman
Structures and biosynthesis of bacterial lipopolysaccharides Yuriy A. Knirel
High resolution mass spectrometry in structural studies of bacterial lipopolysaccharides
The increase in elongation is a very marked process: the length of the cells can increase up to several thousand times. Each of the many models of plant cell elongation works with a category such as cell wall stretching. Furthermore, other cell wall polysaccharides may play an important role in the elongation process.
However, the number of publications comparing the composition and structure of cell wall matrix polysaccharides in extensible and non-extensive tissues was surprisingly low. We have analyzed changes in the localization and structure of the major polysaccharides of the cereal cell wall matrix during elongation growth.
Glycosidases as hydrolases and synthases
Institute of Physiology, Komi Science Center, The Ural Branch of the Russian Academy of Sciences, Syktyvkar, Russia. It has been found that pectins containing 80% and more residues of galacturonic acid reduce activity of macrophages and inhibit reaction of delayed type hypersensitivity (DTH). For example, galacturonic fragments of potamogetonan, oxycoccusan and rauvolfian were found to reduce activity of leukocytes similarly to parent pectins.
A high degree of methylesterification of galacturonic acid residues (more than 50%) was found to break the inhibitory effect of pectins on leukocyte activity. It was established that the presence of fragments of branched galacturonan induces a biphasic immunomodulatory action, namely the decrease in leukocyte activity turns into its increase. Pectins and galacturonans with leukocyte-inhibiting ability have been shown to increase the resistance of laboratory mice to endotoxinemia induced by injection of lipopolysaccharide and have been found to protect mice from acetic acid-induced colon inflammation.
Advanced branching pectins such as lemnan from duckweed Lemna minor, butomosan from grass rush Butomus umbellatus and silenan from campion Silene vulgaris were found to stimulate antigen-nonspecific (phagocytosis) and antigen-specific (DTH, production of antibodies) immune responses. Branched region of silenan was found to consist mainly of linear 1,4-linked beta-galactan and 1,5-alpha-arabinan chains, whereas tanacetane was found to contain significant portions of branched fragments of arabinan and galactan in the side carbohydrate chains. Enhancement of intestinal permeability to antigen was found to mediate stimulation of humoral immune response by lemnan.
Natural plant cell wall pectins appear to have the ability to stimulate and suppress the immune response. Chemical modifications of 1 on the side chain of the aglycone moiety of 1 led to a series of antitumor compounds with lower in vivo toxicity. It has been shown that the presence of O-acyl groups on the sugar branches is crucial for the interaction with DNA, the inhibition of topoisomerase I and the cytotoxic activity of the antibiotic.
Galectins: study of their cellular cis- and trans-ligands
Microbial Cellulose: a sustainable alternative to conventional fibers; process development, scale up, purification & potential applications
Continuous Chemical Education – Approach at Zelinsky Institute Sergey E. Semenov
D. Zelinsky Institute and Moscow Chemical Lyceum
From the beginning of their studies, students of the HCC also have a special free day each week to continue their scientific research started at the Lyceum. Finally, the training at the postgraduate courses of research institutions of the RAS is completed by defending theses and obtaining degree in chemical sciences comparable to PhD. Scientists from institutes of the RAS act as the teachers and establish long-term "tutor-student" pairs, as they are interested in providing follow-up and further development of their scientific schools.
As a result, even the students of MCL are often the co-authors of the scientific articles and conference reports because of their valuable contributions to research projects. One of the main problems in scaling up processes of biocatalytic conversion of LCB is the increase in the catalytic activity of enzyme complexes and individual enzymes. Cytokine-inducing, antioxidant activities and effects on hemostasis of different types of carrageenan (kappa, lambda, kappa/iota, kappa/beta and iks) isolated from the red seaweeds Gigartinaceae and Tichocarpaceae families collected from the Pacific coast were studied.
The reducing capacity of the studied carrageenans was not very pronounced, and the capacity of the commercial polysaccharide samples was negligible. Antioxidant effects of carrageenans against reactive oxygen/nitrogen species depend on polysaccharide concentration and such fine structural features as the presence of a hydrophobic 3,6-anhydrogalactose unit, the amount and position of sulfate groups, and an oxidizing agent against which the antioxidant action of the sample is directed. . The results indicated that carrageenans possess antioxidant capacity in vitro, and this effect mainly depends on the structure of the polysaccharide itself rather than the reducing capacity of the polysaccharides.
Carrageenans were also shown to inhibit aggregation of platelets washed with thrombin or collagen as agonists, and in the case of collagen the effect of carrageenans was more pronounced resulting in an average reduction of 80% for carrageenans and 85% for heparin. The in vivo impact of carrageenans as a food supplement (“Carrageenan-DV”, PIBOC FEB RAS) composed of two carrageenan samples was also determined. The results of this investigation showed that the application of "Carrageenan-DV" as an additional source of dietary fiber during the complex therapy of patients with cardiovascular disorders contributed to the normalization of lipid metabolism indices and the chronic inflammatory process.
Marine carbohydrates
Macromolecular and Carbohydrate Binding Properties of Chitooligosaccharide- specific Phloem Exudate Lectins from two Cucurbitaceae Species
Polysaccharides of the red algae
Fucoidans as a base for drug design Nadezhda E. Ustyuzhanina
Synthesis and Chemical biology of GPI molecules Ram Vishwakarma
POSTERS
High-resolution electrospray mass spectra (MS and MS/MS) of biotinylated, HEG- spacered molecular probe HNK-1 and its desulfated analog
Kiselevsky, 2 Nikolay E. Nifantiev 1
Application of Artificial Neural Networks for the Analysis of NMR Spectra of Natural Fucoidans
The derivatives of isoprenoid biosythesis intermediate 2-C-methyl-D-erythritol-2,4 cyclodiphosphate as new antibiotics
Water-dependent reduction of carbohydrate azides by dithiotreitol
Representative examples of the azide reduction with DTT
Multilateral action of carbohydrates of different classes on all systems of living organisms has been known since ancient times. In the second half of the 20th century, unique properties of 1,3-glycans were discovered, showing pronounced antitumor properties [1]. The effect of these polysaccharides is an incentive for researchers trying to find ways for safer cancer therapy.
Increasing the effectiveness of existing treatment methods can be achieved by supplementing with drugs that increase anti-tumor resistance at the expense of affecting the body's immune system. In this regard, complexes of many metals are of interest, which have been found to have both immunomodulatory and cytotoxic effects [2,3]. We specifically researched many complex compounds of bivalent 3d elements with one of the simplest sugars - gluconic acid [4,5].
It should be noted that the acute toxicity of gluconates is significantly reduced compared to inorganic compounds, at this time it has been shown to preserve the level of cytotoxicity relative to erythroleukemia K562 cells. The synthesized complexes produced immunomodulatory effect (recovery of IgG level after the control), revealed by experiments "in vivo" on the model of immunodeficiency (mice). There is also an increase in long-lived animals (mice of line BALB/c) noted transplantable tumors by tens of percent. We also investigated the effect of gluconates of some elements on another index of humoral immunity - the level of conformational forms of complement component C3 - C3 (H2O), which correlates with the level of tumor marker CA-125 [6,7].
The determination of the С3(Н2О) level was carried out in the process of incubation of venous blood serum of patients suffering from some diseases: breast cancer in stages I-IIА, diffuse and nodular mastopathy, fibrous adenoma, Hodgkin's and non-Hodgkin's lymphomas compared to healthy donors. We have noticed the adjustment of this index; in some cases it did not differ from control (p <0.05).
AGSULAR ® - natural polysaccharide - based pharmacological substance from Siberian larch wood
In this communication, we report the synthesis of fully sulfated oligosaccharides linked by fucoidan chains. The first series of compounds consists of di-, tetra-, hexa-, octa-, dodeca- and hexadecasaccharides 1-6, built from (13)-linked -L-fucopyranose residues, corresponding to polysaccharides isolated from several seaweeds, including Saccharina latissima (formerly Laminaria saccharina), Chorda filum. Another type of compounds is represented by di-, tetra- and hexasaccharide 7-9, built from alternately linked (13) and (14).
Inorganic polyphosphate and sensitivity of yeast cells to cellobiose lipid, a new microbial fungicide
Natural antibodies against glycans from human milk
New aminosugar derivatives of genetically engineered Amphotericin B –type antibiotics S44HP and BSG005: synthesis and antifungal activity
Influence of sulfated cellulose from Pópulus trémula wood on thrombin’s and activated factor X’s activities
Synthesis of the HNK-1 trisaccharide and related oligosaccharides and their use in assessing the carbohydrate specificity of HNK-1 antibodies.
Synthesis of the HNK-1 Trisaccharide and Related Oligosaccharides and Their Application for Assessment of the Carbohydrate Specificity of HNK-1 Antibodies
STUDY ON THE STEREOSELECTIVITY OF CYCLIZATION OF LINEAR β-(16)- OLIGOSACCHARIDES
Federal State Budgetary Institution “Hematological Science Center” of the Ministry of Health and Social Development of the Russian Federation, Moscow. In addition, the proposed sulfated methods of chitosan and pectic polysaccharides from wood greens of Siberian spruce (Abies sibirica L.). Modification of cellulose sulfate by introducing into the polymer structure oligomers of oxyethylene and bulky trityl substituents had been carried out (Fig. 1).
A new effective method for sulfate chitosan without the use of highly toxic organic bases was proposed. The method consists of carrying out the sulfation reaction with swollen polysalt chitosan and n-toluene sulfonic acid in an organic solvent, and using sulfamic acid as sulfating agent (Fig. 2). We believe that the development of an effective method for the synthesis of sulfated derivatives of water-soluble polysaccharides isolated from wood greens of Siberian spruce is an important achievement.
Conducted a preliminary study of hydrodynamic properties of the new sulfated polymers and obtained the first data on their hemorrheological properties. Full assignment of the signals from 1H and 13C NMR and the structure of the antibiotic INA-1278, produced by the experimental strain Streptomyces sp.
Full assignment of the signals of the 1 H and 13 C NMR and the structure of the antibiotic INA-1278, formed by the experimental strain Streptomyces sp
Synthetic nona-β(1→6)-glucosamines with various patterns of N-acetylation representing fragments of an exopolysaccharide produced by Staphylococcus aureus
Effect of natural non-specific immunomodulators – yeast and fungal (1→3)-beta-D- glucans on growth and metastasis of murine Levis lung carcinoma
Local Organizing Committee
Official Service Agent
Symposium Sponsor
