[Extracellular lectins from saprophytic strains of bacteria of the genus Bacillus (review)].

The present review summarizes both the authors' own and other researchers' reports concerning the synthesis and properties of sialic acid-specific extracellular lectins from saprophytic bacteria of the genus Bacillus. Bacilli of this genus isolated from different ecological niches differ with regard to the ability to synthesize lectins. The biphasic temporal pattern of lectin synthesis in culture and the effect of cultivation conditions on lectin production have been demonstrated. The advantages of the technological procedure used for the isolation and purification of these biopolymers have been characterized. Specificity towards sialic acid, which is characteristic only of a small number of lectins from bacilli and underlies a wide range of biological effects of these proteins, receives particular attention. Adaptation mechanisms involving lectins--carbohydrate-recognizing proteins--are suggested to have developed in saprophytic bacilli to ensure the survival of these organisms in a constantly changing environment.

[Chromate reduction by Pseudomonas sp. str. 10 in the presence of some heavy metals and alternative electron acceptors].

Pseudomonas sp. str. 10 reduces chromate with a rate of 0.54 mg / L.h. The availability of Cd2+ and Zn2+ in the medium has no noticeable effect on the rate or slightly increases it. The presence of nickel and copper in the ionic form in the medium resulted in a decrease of chromate reduction rate 2.4 and 4.2 times, respectively. Change of these metals into hydroxide form significantly lowers their negative influence. Iron (III) both in ionic and hydroxide form inhibits the reduction of chromate by Pseudomonas sp. 10. Joint presence of all studied metals decreases their negative impact on chromate reduction, therefore these metals may be neutralized together without a significant lowering of the process efficacy on condition that copper-containing drain will be cleaned separately. The presence of alternative acceptors of electrons inhibited the reduction of chromate. Sulfate and oxyanions of chlorine - chlorate and perchlorate have the highest inhibitory effect on chromate reduction.

[Metabolism features of bacteria resistant to high concentrations of chromate].

Twenty strains of bacteria resistant to high concentrations of chromate were isolated from different ecological niches. They were able to reduce chromate to compounds of trivalent chromium--nonsoluble chromium hydroxide or soluble crystalline hydrates of trivalent chromium. The growth features of these microorganisms on media containing chromate at high concentrations (up to 20.0 g/l) are described. Besides chromate bacteria can reduce vanadate to compounds of V(4+) and Mo(6+) to Mo(5+). The best reduction takes place on the media where MPB. glucose or ethanol serves as the source of carbon. The growth and reduction of anion-in-study did not occur on organic acids. It was shown that tungstate, chlorate or perchlorate were not toxic for the studied bacteria up to concentrations of 10.0 g/l, however were not reduced by these microorganisms. The most active strains belong to genera Pseudomonas, Oerskovia, Bacillus, Micrococcus.

[The ability of actinobacteria to assimilate n-alkanes under nitrate-reducing conditions].

It has been established that the oil-oxidizing strains of actinobacteria--components of the preparation "Ekolan-M" are able to assimilate n-alkanes during microaerobic cultivation in nitrate-reducing conditions. After 7 days of growth in these conditions, the level of biodegradation of n-hexadecane of the investigated strains was 52.0%, which is 1.5 times less than for the same period in the aerobic cultivation. n-Hexadecane utilized by cells was completely mineralized to carbon dioxide, the amount of which in the gas phase reached 1.6% on the 9th day of growth.

[Reduction of chlorate in the presence of heavy metals by Acinetobacter thermotoleranticus C-1].

Influence of heavy metals on Acinetobacter thermotoleranticus C-1 was studied by the rate of chlorate reduction and biomass growth. It was established that Fe3+ in a form of free ion at concentration of 30 mg/l also stimulates both the reduction of chlorate by A. thermotoleranticus C-1 and the growth of biomass, Cd2+ Pb2+ and Mn2+ do not practically affect the process velocity or stimulate it a little, Cu2+ and Zn2+ lower the reduction rate of C10(3)- 2.5-3 times, under these conditions the biomass growth is inhibited more weakly than the reduction rate. Nickel and cobalt in the mentioned amount inhibit completely the process of reduction. Metals in the form of hydroxide-ion proved to be less toxic for str. C-1, than their ion forms. General influence of a free ion, metal hydroxide and the amount of organic nutrition takes more considerable (stimulating or inhibiting) influence on the process, than each of these factors itself.

[Geno- and phenotypic characteristic of Bacillus strains--components of endosporin].

Endosporin is used in veterinary for the prophylaxis and treatment of disbacteriosis, intestinal infections, festering wounds and postpartum pyoinflammatory complications in agricultural animals. The probiotic is based on two Bacillus strains which inhibit growth of a broad spectrum of pathogenic microorganisms and synthesise proteolytic enzymes and other biologically active secondary metabolites, particularly - polysaccharides. The activity of these two strains was supplementary. For the species identification of these strains, sequences of 16S rRNA genes and fatty acid content of cell walls were analysed. It was found that the both strains belong to B. velezensis. Limitations of application of 16S rRNA sequences for identification of closely related species are discussed in the paper. A method of 16S rRNA sequence profiling by polymorphic nucleotides was proposed. It was also shown that usefulness of Bacillus strains in probiotics is mostly based on their unique strain specific properties rather than on general species characteristics.

[Efficiency of the preparation "Ekolan-M" for purification of oil polluted soil].

The efficiency of purification of oil contaminated loamy chernozem by the preparation "Ekolan-M" was investigated. During 12 months a complex soil bioremediation using the preparation and alfalfa, as the land-improving plant, at the final stage of purification resulted in the reduction of hydrocarbon content by 97.0%, and without the preparation - by 65.5 %. In the version of experiment with the preparation a 100% decrease of soil phytotoxicity was achieved and a significant stimulation of plant growth and development was observed. The process of soil purification was accompanied by intensive development of hydrocarbon-oxidizing microorganisms, the amount of which during the process of oil concentration gradually decreased, approaching the level in the control uncontaminated soil.

[Selection of thermophilic lactose-fermenting yeast strains].

The screening and selection of lactose-fermenting yeasts among 97 collection yeast strains belonging to different taxonomic groups has been conducted to obtain ethanol from whey. The strains (n=18) (1 strain of K. lactis. 16 strains of K. marxianus and 1 strain of C. kefyr) fermented lactose at 48 degrees C and 15 selected strains rapidly consumed lactose within 24-48 h of cultivation. The presence of 6% of ethanol in the medium resulted in a considerable growth inhibition (more than 80%) of the selected strains.

[Reduction of chlorates by acinetobacter thermotoleranticus C-1 in the presence of chromate ions].

The rate of chlorate reduction by A. thermotoleranticus C-1 reached 59.6-63.7 mg/l an hour and did not practically depend on chlorate concentration in a broad range. Chlorate and chromate being jointly present in the medium, the rate of chlorate-reduction depended on chromate concentration and remained at the same level when content of chromate reached 5 mg/l. Under CrO4(2-) of 10.0 mg/l the reduction of chlorate by A. thermotoleranticus became inconsiderably slower. The increase of CrO4(2-) content to 20.0-30.0 mg/l decreased the chlorate reduction rate from 63.7 to 18.3-5.8 mg/l an hour, and availability of 50.0 mg/l of chromate was the inhibiting concentration for chlorate destruction and led to irreversible loss of the capacity ofA. thermotoleranticus C-1 to reduce chlorate. The reduction of chromate proceeded simultaneously with that of chlorate. The rate of chromate reduction by A. thermotoleranticus C-1 under their content in the medium of 3-20 mg/l was 0.5-0.37 mg/l an hour and decreased considerably with the increase of concentration of chromate-ions. Availability of chlorate had no effect on reduction of chromate by A. thermotoleranticus C-1.

[Study of vaginal and intestinal microflora of women in the prenatal period and its correction in dysbacteriosis].

A comparative research of the structure of vaginal and intestinal microflora in norm and at kidney pathologies in women in the prenatal period was carried out. At physiologically normal course of pregnancy microbiocenosis of vagina and intestine does not contain pathogenic and conditional-pathogenic microorganisms. Lactic acid bacteria are fixed within the limits of 10(5)-10(8) CFU/1 ml in the vagina secretion and 10(7)-10(8) CFU/1 g in the intestine content. The spore microorganisms have completely disappeared in vaginal biocenosis of women with pyelonephritis after pharmacotherapy; and colibacterias has disappeared in 62% of women. Quantity of lactic acid bacteria has also decreased. Quantity of E. coli (10(8)- 10(9)) CFU/g, sporous microorganisms (10(3)-10(4)) CFU/g and yeast (10(4)-10(5)) CFU/g has considerably increased in the content of intestine. Lactic acid bacteria in content of the vagina are presented by: Lactobacillus acidophilus, L. plantarum, L. fermentum, L. vaginalis; in content of the intestine--L. plantarum and L. fermentum. All the isolated strains of lactobacilli are resistant to metrogyl and amphotericin, 87%--to cephoxitine, cypropfloxacine. Twenty three of 24 strains of lactic acid bacteria--antagonists of pathogenic microflora have shown adhesion to vaginal epthelium. The degree of adhesive activity depends on the strain and genus specificity of cultures. The highest index of adhesiveness in indicated in Enterococcus faecium (5.82 - 7.62) and Streptococcus salivarius subsp. thermophilus (2.74 - 6.40) strains. The screening of strains has been performed, which suppress growth of gas-producing microflora. The strain of Lactobacillus plantarum 200D proved to be the most active one. A complex of cultures of the lactic bacteria providing normalization of microbial cenosis of the vagina in women in the prenatal period has been selected as based on the data obtained. The biotechnology of production of vaginal suppositories is developed.

[Reversion of antibiotic-sensitivity of lactic acid bacteria in grafted cultures of lymphoblastoid human cells].

The reversion of the antibiotic sensitivity of lactic acid bacteria: Streptococcus salivarius subsp. thermophilus, Enterococcus faecium, Lactobacillus plantarum have been studied. The phenomenon of the reversion has been fists studied in lactic acid bacteria of different taxonomic groups at their interactions with lymphoblastoid human cells. It is shown that resistance of lactobacteria to antibiotics can change depending on the terms of cultivation, genus and strain specificity. Most often the reversion of antibiotic sensitivity was observed with respect to fuzidin (26%) and cefepim (23%), most rarely--with respect to cephazolin, erithromicin, cefamandol, tobramicin and oxacillin.

[Interferon induction by lacticacid bacteria in vitro and in vivo experiments].

Interferonogenic acitivity of lacticacid bacteria was studied in experiments in vitro and in vivo. It have been shown, that interferon induction depends both on strain species and on culture medium used for lactobacteria harvesting. Streptococcus thermophilus induces interferon more actively in leucocytes (in vitro)--1280 AU/ml on the bines broth medium, and less actively--320 AU/ml on fermented corn medium. Interferon induction in human leucocytes was not registered in case of L. plantarum 200 strain. In vivo experiments show that E. faecium strain and strain mixture of streptococcus termophilus are active interferon inductors. Induced interferon is recognized as alpha- and gamma-interferon, with domination of alpha-interferon.

[Assessment of probiotics according to the international organizations (FAO/WHO)].

The guidelines of international organizations (FAO/WHO) are presented in the paper for the purpose of estimation of probiotic properties of the strains of microorganisms as well as functional food products in respect of their influence on health. Modern scientific researches served as the basis for minimum requirements necessary for the competence of probiotic status. The chart of the experiment sequence is presented that has to be used for probiotics estimation: bacteria systemizing with the use of phenotype and genetic techniques, description of functional properties of the probiotic and estimation of its safety. The in vitro tests for determination of safety of probiotics are described.

[Protective action of electromagnetic radiation (40.68 MHz) on Saccharomyces cerevisiae UCM Y-517]. / Protektornoe deistvie élektromagnitnogo izlucheniia (40.68 MHz) na Saccharomyces cerevisiae UKM Y-517.

Electromagnetic radiation (EMR) (40.68 MHz, 15 and 30 W) has been studied for its effect on survivability of cells of Saccharomyces cerevisiae UCM Y-517 under the extremal influence of the environment factors (pH, freezing-thawing, nistatin (1.0 microg/ml)). It is shown that even short-term irradiation of the yeast suspension (during 5 min) takes protective effect under the conditions of stress factors, displayed in the increase of the number of live intact cells. It was established by cytochemical methods that 50-70 % of cells were characterized as damaged and dead in the control samples after yeast exposition under the stress conditions. Such an effect was not observed in the samples of preliminary irradiated cells. The pool of extracellular nucleotides was shown to decrease as a result of the yeast cells irradiation; one could also observe the decrease of these cells ability to acidity the culture medium. The increase of activity of intracellular enzymes of dehydrogenase complex was noted as well. Stability of electrostatic characteristics of the cell surface (zeta-potential) and catalase activity under the effect of EMR of radio-frequency range has been demonstrated. The found effect of protective action of EMR of the above frequency is of nonspecific character, which allows its mechanism universality to be supposed.

[Adhesion of lactic acid bacteria to epithelium of different cavities of the human organism]. / Adgeziia molochnokislykh bakterii k épiteliiu razlichnykh polostei organizma cheloveka.

During investigation of adhesive properties of lactic acid bacteria it was found out that 11 strains adhered to buccal intestinal and vaginal epithelium of human. The highest adhesive activity was detected in enterococci (adhesive index 7.75-14.26), lower one--in streptococci (6.40-9.16). In lactobacilli adhesive properties manifested in different ways: Lactobacillus acidophilus strains adhered more often to buccal epithelium (2.58-4.60) and rarely--to intestinal and vaginal. L. plantarum manifested high adhesive activity (8.03 -9.69) to buccal epithelium and lower one--to the rest of epithelium types. Monosaccharide composition of glycocalix of 6 strains of lactic acid bacteria was studied to understand the adhesion mechanism. It was shown that surface structures of this microorganism interact with plant lectins, specific to certain monosaccharides.

[Effect of chromium (VI) on growth physiology and sorptional capacity of yeast]. / Vliianie khroma (VI) na fiziologiiu rosta i sorbtsionnuiu sposobnost' drozzhzhei.

Resistance of 7 yeast species (7 strains) to various chrome concentrations in the medium and their sorptional activity have been studied. It is shown that the biomass of the yeast Williopsis californica UKM-248, Candida krusei UKM-61t under their concentration in the medium of 200 and 500 mg/l of Cr6+ is 0.74 and 0.45 g/l DWB, respectively. For the rest of strains these chrome concentrations are toxical and the concentration of 100 mg/l of Cr6+ is the bordering threshold for them. Under periodical cultivation in the medium with 30 mg/l of Cr6+ one can observe the delay of cultures growth displayed in the increase of the lag-phase and exponential growth phase as well as the decrease of medium pH (to 2). The resistance of the studied yeast to high concentrations of Cr6+ correlates with their sorptional activity.

[Effect of radio-frequency electromagnetic radiation on physiological features of Saccharomyces cerevisiae strain UCM Y-517]. / Vliianie radiochastotnogo élektromagnitnogo izlucheniia na fiziologicheskie osobennosti Saccharomyces cerevisiae UKM Y-517.

Effect of electromagnetic radiation (40.68 MHz) on growth characteristics of Saccharomyces cerevisiae strain UCM Y-517 has been studied. Reliable increase of the specific growth rate (by 7-15%) and change of duration of growth phases as a result of irradiation of yeast population has been shown. The EMR effect has been found to depend on physiological state of the irradiated cells and composition of the irradiation performance medium: reliable effects were found only for the cells preliminarily grown on the dense nutrition medium in the late phase of delayed growth or on achieving the stationary growth phase. The role of radiation term and power as well as of temperature factor in EMR effect on the cells is discussed. It has been noted that the dependence of specific growth rate of yeast on the initial density of cells population acquire the nonlinear character as affected by EMR of radiofrequency range.

[Search of heavy metals biosorbents among yeasts of different taxonomic groups]. / Poisk biosorbentov tiazhelykh metallov sredi drozhzhei razlichnykh taksonomicheskikh grupp.

The use of microbial cells as heavy metal biosorbents is a potential alternative for the existing methods of the environment treatment for pollution by these metals. Yeast may be successfully used in the metals sorption. An agar-plate screening method was used for rapid isolation of metal-accumulating strains of yeast and preliminary estimation of their biosorption capacity. The capacity to accumulate heavy metals, such as copper, zinc, lead, chrome and cobalt was estimated in 68 pigmented and pigmentless yeast strains isolated from different sources. The best capacity of copper and zinc accumulation was shown by pink-coloured Rhodotorula mucilaginosa, Rhodotorula aurantiaca, Rhodotorula glutinis and pigmentless strains of the yeast Candida krusei, Williopsis california.

[Yeasts--biosorbents of heavy metals]. / Drozhzhi--biosorbenty tiazhelykh metallov.

The sharp increase of the level of environment pollution by heavy metals caused the increase of interest to the problem of live organisms (including microorganisms) resistance to these metals. Biosorption is one of the mechanisms of microorganisms resistance to heavy metals. Yeasts as biosorbents are of special interest. An analysis of the data from literature have shown that the yeast biomass may be used successfully as biosorption material for such metals as Ag, Au, Cd, Co, Cr, Cu, Ni, Pb, U, Th, Zn. Yeasts of genera Saccharomyces, Candida, Pichia are efficient biosorbents of metals. The sorptional system estimation is based on the classic sorption isotherm obtained in the course of equilibrium experiments and depends on pH, properties of metal ions, biomass concentration, preliminary physical or chemical treatment of the biomass, presence of various organic and inorganic ions and on temperature. The yeast biomass may be obtained using numerous industrial processes, that decreases considerably the biosorbent cost. Most yeasts can sorb a wide range of metals or be strictly specific in respect of only one metal. Special attention would be paid to the cell wall which structure determines sorption proceeding mechanisms. Problems of mechanisms of heavy metal biosorption by microorganisms at molecular level are discussed. The review also deals with the newest developments on improving the biosorption processes in microorganisms, yeast in particular.

[Leaching of calcium, silicon, aluminum and iron from micromycetes grown in submerged culture in the presence of ground concrete]. / Vyshchelachivanie kal'tsiia, kremniia, aliuminiia i zheleza pri roste mikromitsetov v prisutstvii izmel'chennogo betona v usloviiakh glubinnogo kul'tivirovaniia.

The leaching of chemical elements from concrete by microfungi of genera Aspergillus and Cladosporium during fungal growth on the medium containing ground barrier concrete under submerged conditions has been studied. It was shown that the leaching of chemical elements depended on the process of growth and metabolites excretion, on fungi species and on concrete concentration on the medium. Specificity of metals mobilization by different fungi was found.