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I V Botvinko

Publications and source records attributed to I V Botvinko.

17 recordsLinked to original sources
PubMed1993

[Structure of the repeating unit of the intracellular polysaccharide from Mycobacterium convolutum 240].

An acidic extracellular polysaccharide composed of D-glucose, L-fucose, D-glucuronic acid and pyruvic acid residues has been isolated from the Mycobacterium convolutum culture fluid. On the basis of methylation analysis and 13C NMR data, the structure of the repeating unit of the polysaccharide was deduced as follows: -->3)-beta-D-Glcp-(1-->4)-beta-D-GlcpA-(1-->4)-alpha-L-Fucp- (1--> [formula: see text]

Carbohydrate Sequence↗
PubMed1991

Structure of the major exopolysaccharide produced by Azotobacter beijerinckii B-1615.

A. beijerinckii strain B-1615 produced two acidic exopolysaccharides in the ratio approximately 9:1. The minor polysaccharide contained mannuronic and guluronic acids in the ratio 2.3:1 and is a bacterial alginate. The major polysaccharide consisted of D-galactose, L-rhamnose, and pyruvic acid in the ratios 2:1:1 and was acetylated. On the basis of methylation analysis, and 1H- and 13C-n.m.r. spectroscopy of the polysaccharide before and after removal of the pyruvic acid residues and O-deacetylation, it was concluded that the major polysaccharide had the structure [formula; see text] with up to 1.5 OAc groups per repeating unit.

Azotobacter↗
PubMed1990

[The electron microscopic study of bacterial development in colonies. The heteromorphous growth of bacteria during the natural development of a population].

In this work data on the morphological features of the heteromorphous growth of bacteria in the process of the natural development of their population are presented. The authors believe that the heteromorphous growth of cells is inherent in the normal cycle of the development of bacteria in the population and that this process is reversible. It has certain regularities, common for different bacteria, in the variability of morphological manifestations and can be regarded as one of the stages of the natural L-transformation of bacteria.

Culture Media↗
PubMed1990

[Electron microscopic study of bacterial development in colonies. The morphology of bacterial colonies].

The morphology of colonies of some pathogenic Gram-negative and Gram-positive bacteria has been studied by scanning and transmitted electron microscopy. The presence of covers on the surface of cells in colonies has been revealed. The examination of colony fragments in ultrathin section has revealed that cells exist in associations and the elements of cell covers are differentiated in the form of fibrillar structures in the intracellular space. This investigation has shown that covers in the colonies of the bacteria under study should be regarded as their morphological feature playing an important role in the development of the infectious process.

Cell Membrane↗
PubMed1983

[Mechanism of action of an exopolysaccharide from Mycobacterium cyaneum on the local cellular reaction in experimental coli infection].

A study was made of the effect of the exopolysaccharide (PS) M. cyaneum B-646 on cellular reaction in peritoneal exudate of white mice infected with E. coli. PS intensified the migration of phagocytic cells to the focus of infection, accelerated neutrophil maturation, promoted an earlier and more active involvement of neutrophils, particularly of macrophages, into the phagocytic process. In this case, there was a marked correlation between the magnitude of phagocyte population (of macrophage population to a greater degree) in peritoneal exudate and absorption capacity. PS activated macrophagal lysosomes, affecting selectively the accumulation of enzymes by the cells and lysosomal membrane permeability. The action of PS is dose-dependent. Under experimental conditions in question, the most favourable effect on local cellular reaction was exerted by PS in a dose of 20 micrograms per mouse.

Acid Phosphatase↗
PubMedDate not supplied

[Colonial organization and intercellular communication of microorganisms].

This review covers the modern concepts and recent data demonstrating the integrity and coherence of microbial populations (colonies, biofilms, etc.) as peculiar "super-organisms." Special attention is given to such relevant phenomena as apoptosis, bacterial altruism, quorum effects, collective differentiation of microbial cells, and the formation of population-level structures such as an extracellular matrix. Emphasis is placed on the channels in colonies and agents of intercellular communication in microbial populations. The involvement of a large number of evolutionarily conserved communicational facilities and patterns of intercellular interactions is underscored. Much attention is also given to the role of colonial organization and intercellular communication in parasite/commensal/symbiont-multicellular host organism systems.

Apoptosis↗
PubMedDate not supplied

[Isolation of hydrocarbon-oxidizing psychrophilic bacteria from oil-polluted soils].

Microorganisms growing on a mineral medium with crude oil and its light fractions as only carbon and energy sources have been isolated from samples of oil-polluted soils collected in the Usa District (Komi Republic, Russia). For the first time, hydrocarbon-oxidizing psychrophilic bacteria of the genus Cytophaga have been found that are clearly capable of consuming crude oil hydrocarbons. A method for cultivating microorganisms on porous plastic is proposed. The data from the literature on the response of soil microbiota to oil pollution indicate that the pollution can activate or suppress the growth of various physiological groups of microorganisms [1]. Different soil and climatic conditions and pollution levels can give rise to different microbial cenoses, which include different associations and predominant microbial species.

Biodegradation, Environmental↗
PubMedDate not supplied

[Exopolysaccharide and proteolytic enzyme synthesis by M-, S- and R-forms of Mycobacterium lacticolum].

The composition of exocellular polysaccharides was studied in the M, S and R variants of Mycobacterium lacticolum 104. The exoglycans of the M and S variants were found to be rather similar but differ considerably from the exoglycan of the R form. The polysaccharides of the M and S cells contained glucose, mannose, galactose, and pyruvic acid; the exoglycan of the R cells contained also the fourth sugar arabinose, but lacked pyruvic acid. The specific rotation of the polysaccharides from the M, S and R variants ([alpha]d20), respectively, was +207.5, +168.0 and +25.0. The caseinolytic activity of the M, S and R variants, respectively, by the seventh day of growth was 0.93+/-0.21, 0.62+/-0.07 and 0.47+/-0.07 units/ml.

Chemical Phenomena↗
PubMedDate not supplied

[Comparative study of the chemical composition and properties of the capsule polysaccharides in M-, S- and R-variants of Mycobacterium lacticolum].

Polysaccharides from the capsules of Mycobacterium lacticolum M, S and R variants were comparatively studied for the first time. The polysaccharides from M and S cells contained galactose, glucose and mannose; however, the polysaccharides must be different since they vary in specific rotation. The capsule polysaccharide from R cells contained also arabinose. Its specific rotation differed considerably from those of M and S cells. The polysaccharides are involved in phage adsorption on mycobacterial cells, and the three variants show differences in this respect. The free exopolysaccharides of M, S and R variants are identical with the corresponding capsule exoglycans, and their proportions differ among the variants.

Free Radicals↗
PubMedDate not supplied

[Conditions for extracellular heteroglycan biosynthesis by Mycobacterium salivarium].

Mycobacterium salivarium 76 was found to synthesize the individual exoglycan unbound to proteins and lipids in media containing various sources of carbon (sugars, polyatomic alcohols, n-alkanes) and nitrogen (nitrates and ammonium salts) at pH from 6 to 10. These compounds determined the quantitative yield of glycan, but had no effect on its monomeric composition represented by glucose, mannose, uronic acid and pyruvate residues. The highest yield of biomass and polysaccharide was found in the medium with n-dodecane and KNO3 at pH 7.0.

Culture Media↗
PubMedDate not supplied

[Extracellular polysaccharides of saprotrophic mycobacteria and patterns of their formation].

Exocellular polysaccharides were synthesized by ten strains of 7 saprotrophic mycobacterial species in parallel with their growth. The cultures grew and produced polysaccharides more rapidly in a medium with glucose than in a medium with n-hexadecane. The polymers are homogeneous acid heteroglycans of the regular structure. All of them contain glucose and some of them contain hexuronic acid. Galactose, fucose, mannose, ramnose and pyruvic acid are found in some of the polysaccharides. The exoglycans of two mycobacterial species contain mannolactylic acid. Beta-glycosidic linkages prevail in most of the polysaccharides.

Alkanes↗
PubMedDate not supplied

[Conditions for exopolysaccharide biosynthesis by Mycobacterium mucosum and its composition].

Mycobacterium mucosum 32 synthesizes an extracellular heteropolysaccharide during its growth in media with different sources of carbon (sugar, polyatomic alcohols, n-alkenes) and nitrogen (nitrates, ammonium salts) within the pH range from 6 to 10. The yield of the polysaccharide depends on the cultural growth and on several factors of the medium. The monosaccharide composition of the glycan does not change depending on the conditions. It contains glucose, galactose, mannose and uronic acid. This exopolysaccharide is an individual compound which is not bound to proteins or lipids.

Chromatography, Gas↗
PubMedDate not supplied

[Intercellular matrix of Bacillus subtilis 271: polymeric composition and function].

It was found that the intercellular matrix of Bacillus subtilis 271 mainly consists of alpha-1,4-glucan (65% of dry matter), branched at some C-3 residues of the polymeric chain, and poly-D-glutamic acid (19% of dry matter). The kinematic viscosity of aqueous solutions of the native matrix was four times as great as that of deproteinized matrix. Increasing the pH of aqueous solutions of the native matrix from 4 to 6 or decreasing their temperature from 38.5 to 11.5 degrees C caused a three- and sevenfold increase in the viscosity of these solutions, respectively. The integrity of the matrix appears to be essential for maintaining the homeostasis of Bacillus subtilis populations.

Bacillus subtilis↗
PubMedDate not supplied

[Effect of serotonin (5-hydroxytryptamine) on the growth and differentiation of microorganisms].

Serotonin (5-hydroxytryptamine), a neurotransmitter and social behavior factor in higher animals, accelerates culture growth and induces cell aggregation in Escherichia coli and Rhodospirillum rubrum at concentrations of 2 x 10(-7)-2 x 10(-5)M. In the myxobacterium Polyangium sp., 10(-6)-10(-5)M serotonin stimulates cell aggregation and myxospore formation. At concentrations over 20 microM, serotonin induces the opposite effect: it inhibits cell aggregation and microbial culture growth. Serotonin at these concentrations also inhibits the light-dependent membrane potential generation in Rsp. rubrum (the data were obtained by the method of penetrating ions). Therefore, the above effects can be due to the elimination of the transmembrane electrical gradient by serotonin. As for micromolar serotonin concentrations, their effects presumably result from the specific action of serotonin as an intercellular communication agent accelerating and possibly synchronizing the development of the cell population.

Cell Division↗