[Influence of heavy metals on surfactants synthesis by Nocardia vaccinii IMV B-7405].

The production of surfactants by Nocardia vaccinii IMV B-7405 in glycerol -and hydrocarbon-containing medium after addition Cd(3+) Pb(2+) and Cu(2+) was investigated. It was established that the introduction of 0.1 mM Cu(2+) in the exponential growth phase of IMV B-7405 strain or simultaneous addition of Cu(2+) (0.1 mM) and Cd(2+) (0.3 mM), Cu(2+) (0.1 mM) and Pb(2+) (0.3 mM) in stationary phase was accompanied by the increase of conditional concentration of the surfactant (by 53 and 20-26%, respectively) compared with indexes in the medium without metals cations. It was established that the surfactants of N. vaccinii IMV B-7405 possessed protective functions from heavy metals influence. After surfactants elimination the survival of cells of strain IMV B-7405 in the presence of Cu(2+) (1.5-2.5 mM), Cd(2+) or Pb(2+) (0.1-0.3 mM) decreased a few times (to 5-45%). The inhibition action of Cu(2+) on alkane hydroxylase activity (the first enzyme of hydrocarbon catabolism) and stimulation--on phosphoenolpyruvate synthetase (enzyme of surface-active glycolipids biosynthesis) in MB B-7405 have been established.

[Synthesis of surfactants by Rhodococcus erythropolis IMV Ac-5017, Acinetobacter calcoaceticus IMV B-7241 and Nocardia vaccinii IMV B-7405 on industrial waste].

The synthesis of surfactants by Rhodococcus erythropolis IMV Ac-5017, Acinetobacter calcoaceticus IMV B-7241 and Nocardia vaccinii IMV B-7405 on industrial waste (food and oil-processing industry, production of biodiesel) was investigated. The possibility of replacing the expensive substrates (n-hexadecane and ethanol) by industrial waste (oil and fat industry, fried sunflower oil, glycerol, liquid paraffin) for the surfactant biosynthesis was established. The conditional concentration of surfactants was maximal on oil containing substrates and exceeded those on n-hexadecane and ethanol 2-3 times. The highest rates of surfactants synthesis were observed on fried sunflower oil with the use of inoculum grown on carbohydrate substrates (glucose, molasses). It was established that the addition of glucose (0.1%) was accompanied by 2-4-fold intensification of surfactants synthesis by R. erythropolis IMV Ac-5017 and N. vaccinii IMV B-7405 on fried sunflower oil (2%).

[Biodiversity of sulfate-reducing bacteria growing on objects of heating systems].

It was shown that sulfate-reducing bacteria developed on the sections of Kyiv municipal heating systems, which are exploited in conditions of different temperatures. The bacteria were different as to their morphological and physiological properties. The bacteria of Desulfovibrio genus were revealed on the sections, which were exploited at a temperature of 35-40 degrees C and bacteria of Desulfomicrobium and Desulfotomaculum genera were revealed on the sections with a higher temperature such as 60 degrees C. Based on of the 16S rRNA gene analysis data, it was demonstrated that sequences of TC2, TC3 and TC4 clones related to Desulfovibrio sp. DSM 12803 (100% sequence similarity), Desulfotomaculum sp. ECP-C-5 (92% sequence similarity) and Desulfomicrobium baculatum strain DSM 2555 (99% sequence similarity), respectively. The identified bacteria are potentially dangerous for heating systems and can be the agents of microbial corrosion.

[Antagonistic activity of Bacillus amyloliquefaciens subsp. plantarum IMV B-7404 and BIM B-439D strains towards pathogenic bacteria and micromycetes].

In this study the antagonistic activity of strains Bacillus amyloliquefaciens subsp. plantarum IMV B-7404 and BIM B-439D against bacterial and fungal pathogens of agricultural crops has been researched. It is shown that both strains of bacilli demonstrated a high level of antagonism to the vascular bacteriosis pathogen, average level of antagonism to micromycetes--root rot pathogens. To ofiobulez pathogen strain B. amyloliquefaciens subsp. plantarum BIM B-439D was more active. Cultural liquid of this strain effectively inhibited the spore's germination of pathogenic micromycetes Penicillium expansum and Botrytis cinerea. Both strains of bacilli synthesized several hydrolytic exoenzymes: proteases, amylases, ß-glucanases, chitinases and xylanases. The obtained data suggest the possibility of expanding the range of strain B. amyloliquefaciens subsp. plantarum BIM B-439D application for plant protection, as well as the need for further researches of the exometabolites spectrum of strain B. amyloliquefaciens subsp. plantarum IMV B-7404 and their biological activity in order to create an effective bioformulation for crop protection.

[Antiadhesive potencial of Rhodococcus erythropolis IMB Ac-5017 biosurfactants].

The effect of Rhodococcus erythropolis IMB Ac-5017 biosurfactants (surface-active substances, SAS) with different degree of purification on attachment of bacteria (Escherichia coli IEM-1, Bacillus subtilis BT-2, Proteus vulgaris BT-1, Staphylococcus aureus BMC-1, Pseudomonas aeruginosa P-55, Enterobacter cloacae AC-22, Erwinia aroidaeae B-433), yeasts (Candida albicans D-6) and fungi (Aspergillus niger P-3, Fusarium culmorum T-7) to the abiotic surfaces (glass, plastic, ceramics, steel, linoleum) was studied. The dependence of microorganisms adhesion on degree of SAS purification (supernatant, purified SAS solution), SAS concentration (0,04-1,25 mg/ml), type of surface and test-cultures was established. The adhesion of majority investigated bacterial cells after treatment of abiotic surfaces with supernatant of cultural liquid with SAS concentration 0,06-0,25 mg/ml was on the average 20-45, yeasts C. albicans D-6--30-75% and was less than that purified SAS solution with the same concentration. Higher antiadhesive activity of supernatant as compared to purified SAS solution testifies to possibility of exception of the expensive stage of isolation and purification at obtaining of preparations with antiadhesive properties.

[Possibility of the plasmid transfer within bacteria - compounds of the sulfidogenic microbial community].

Extrachromosomal elements have been found within the isolates of ammonifying and iron-reducing bacteria obtained from the natural sulfidogenic community. These elements were small with size approximately 5-9 kb. Transconjugant strains Pseudomonas aeruginosa 27, P aeruginosa 28, P mendocina 29, Aeromonas hydrophila/caviae 30, harboured plasmids RP4 and R68.45 were obtained. The conjugation rate and retention of the plasmid within transconjugants were studied. P mendocina 29 cells with conjugation rate - 3.0*10(-6) CFU/ recipient cell, and P. aeruginosa 27 with rate 2.4*l0(-7) CFU/recipient cell were the most susceptible to R68.45 plasmid. The most stable retention is shown for transconjugated strains such as P aeruginosa 27 (R68.45), P. aeruginosa 27(RP4), P. mendocina 29(R68.45), A. hydrophila/caviae 30(RP4), A. hydrophila/caviae 30(R68.45). Thus, it was experimentally shown that corrosive-relevant bacteria form sulfidogenic microbial community which is able to accept extrachromosomal genetic elements from other bacteria when they act as recipients in conjugational process.

[Effect of univalent cations on synthesis of surfactants by Acinetobacter calcoaceticus IMV B-7241].

The effect of univalent cations on activity of key enzymes of C2-metabolism has been investigated in the producer of biosurfactants, Acinetibacter calcoaceticus IMV B-7241 grown on ethanol. It was established that potassium cations are inhibitors of pyroquinolinequinone-dependent alcohol- and acetaldehyde dehydrogenases, the enzymes of biosynthesis of surface-active aminolipids (NADP-dependent glutamate dehydrogenase) and glycolipids (phosphoenopyruvate (PhEP)-carboxikinase), while ammonium cations are activators of these enzymes and PhEP-carboxylase. A decrease of potassium cations concentration in the cultivation medium to 1 mM and increase of the content of amine nitrogen to 10 mM as a result of potassium nitrate substitution by equimolar, as to nitrogen, urea concentration were accompanied by the increase of activity of enzymes of ethanol metabolism and SAS biosynthesis, as well as by the 2-fold increase of conditional concentration of the biosurfactants.

[Effect of surface-active substances of Acinetobacter calcoaceticus IMV B-7241, Rhodococcus erythropolis IMV Ac-5017, and Nocardia vaccinii K-8 on phytopathogenic bacteria].

The effect of surface-active substances (SAS's) of Acinetobacter calcoaceticus IMV B-7241, Rhodococcus erythropolis IMV Ac-5017, and Nocardia vaccinii K-8 on phytopathogenic bacteria has been studied. It was shown that the survival of cells (10(5)-10(7) in a milliliter) of the Pseudomonas and Xanthomonas phytopathogenic bacteria was found to be 0-33% after treatment with SAS preparations of the IMV Ac-5017 and IMV B-7241 strains for 2 h (0.15-0.4 mg/mL). In the presence of N. vaccinii K-8 SAS preparations (0.085-0.85 mg/mL), the number of cells of the majority of the studied phytopathogenic bacteria decreased by 95-100%. These data show prospects for using microbial SAS's for the construction of ecologically friendly drugs for regulating the number of phytopathogenic bacteria.

[Effect of growth factors and some microelements on biosurfactant synthesis of Acinetobacter calcoaceticus IMV B-7241].

The effect of yeast autolysate and microelements on synthesis of surface-active substances (SAS, biosurfactants) was investigated under cultivation of Acinetobacter calcoaceticus IMV B-7241 on various carbon substrates (n-hexadecane, ethanol, glycerol). The authors have shown a possibility to substitute the yeast autolysate and microelement mixture in the composition of ethanol- and n-hexadecane-containing media by copper sulfate (0.16 micromol/l) and iron sulfate (3.6 micromol/l), and in the medium with glycerol by 0.21 mmol/l of KCl, 38 micromol/l of zinc sulfate and 0.16 micromol/l of copper sulfate. Under such conditions of cultivation of the strain IMV B-7241 the SAS concentration exceeded that on the initial media, which contained the yeast autolysate and microelements, 1.2-1.6 times. The authors have also established the activating effect of low (0.01 mM) concentrations of Fe2+ on activity of the enzymes of biosynthesis of surface-active amino- (NADP-dependent glutamate dehydrogenase) and glycolipids (phosphoenolpyruvate(PhEP)-synthetase, PhEP-carboxykinase), as well as of anaplerotic reaction(PhEP-carboxylase). A necessity to introduce zinc cations into glycerol-containing medium is determined by their stimulating effect on activity of 4-dinitroso-N,N-dimethylaniline-dependent alcohol dehydrogenase--one of the enzymes of this substrate catabolism in A. calcoaceticus IMV B-7241.

[Lectin-binding analysis of the biofilm exopolymeric matrix carbohydrate composition of corrosion-aggressive bacteria].

The carbohydrate components of biofilms of corrosion-aggressive bacteria were studied by transmisstion electron microscopy using lectins labeled with colloidal gold. N-acetyl-D-glucosamine, N-acetyl-D-galactosamine, and neutral carbohydrates D-glucose and D-mannose were found within the exopolymeric matrix. Lectins with equal carbohydrate specificity demonstrated different degrees of interaction with the carbohydrate components of bacterial biofilms. To identify N-acetyl-D-galactosamine in biofilms of Desulfovibrio sp. 10 and Bacillus subtilis 36, the LBA lectin appeared to be most specific; in the case of N-acetyl-D-glucosamine in biofilms of B. subtilis 36 and Pseudomonas aeruginosa 27, the WGA lectin. During visualization of neutral carbohydrates in the studied cultures, the PSA lectin was most specific. We have shown that lectins labeled with colloidal gold could be used as an express method for the identification and localization of carbohydrates in glycopolymers of the biofilm exopolymeric matrix.

[Role of polymer complexes in the formation of biofilms by corrosive bacteria on steel surfaces].

The composition of exopolymer complexes (EPCs), synthesized by the monocultures Desulfovibrio sp. 10, Bacillus subtilis 36, and Pseudomonas aeruginosa 27 and by microbial associations involved in the corrosion of metal surfaces has been studied. An analysis of the monosaccharide composition of carbohydrate components, as well as the fatty acid composition of the lipid part of EPCs, was carried out by gas-liquid chromatography (GLC). It was found that bacteria in biofilms synthesized polymers; this process was dominated by glucose, while the growth of bacteria in a suspension was marked by a high rhamnose content. Hexouronic acids and hexosamine have been revealed as a part of B. subtilis 36 and P. aeruginosa 27 EPCs. Qualitative differences were revealed in the fatty acid composition ofexopolymers in biofilms and in a bacterial suspension. It was shown that the transition to a biofilm form of growth led to an increase in the unsaturation degree of fatty acids in the exopolymers of associative cultures. The results can be used to develop methods to control microbial corrosion of metal surfaces.

[Biologically active substances of preparation avercom].

The preparation avercom created on the basis of ethanol extracts from the biomass of Streptomyces avermitilis UCM Ac-2179, contains an antiparasitic antibiotic avermectin, as well as a complex of biologically active substances: amino acids, lipids, including nonsaturated fatty acids, and phytohormones, particularly: auxins, cytokinins, hybberellins. The above mentioned complex is characterized by nematocidical, phytostimulating and elicitor effect upon plants which has been confirmed with the results of production experiments on the cucumber variety Angelina.

[Synthesis of surfactants acinetobacter calcoaceticus IMV B-7241 and Rhodococcus erythropolis IMV Ac-5070 in the medium with glycerol].

It was established that glycerol, a byproduct of biodiesel production, may be used as substrate for synthesis of surfactants Rhodococcus erythropolis IMV Ac-5017 and Acinetobacter calcoaceticus IMV B-7241. Maximum indices of surfactants synthesis by the strain IMV B-7241 have been fixed, when the medium with glycerol included yeast autolysate and trace elements. It was shown that the surfactants synthesis could be intensified when cultivating A. calcoaceticus IMV B-7241 and R. erythropolis IMV Ac-5017 on the mixture of hexadecane and glycerol in concentration of 0.5-1.0% (in volume). When using inoculate grown on hexadecane, the conditional concentration of the surfactant A.calcoaceticus IMV B-7241 on the mixed substrate was higher by 56-100, and that of R. erythropolis IMVAc-5017 by 260-320 % than on the monosubstrate glycerol. The paper is presented in Russian.

[Role of biocompatible adhesives in the increase of rhizobia physiological activity and productivity of soybean-rhizobia symbiosis].

On the basis of natural exopolysaccharide xanthan and exopolyacrylamide the sticky-gene composition has been developed. Addition of that composition to the culture medium provided a 26.3 times higher viability of Bradyrhizobium japonicum UCM B-6035 cells during its storage. Introduction of plant growth regulators biosil or ivin into this composition increased the survival of rhizobia. Application of gel inoculant B. japonicum favored more intensive growth of rhizosphere microorganisms, nutrient's accumulation in the soil and increased productivity of soybean-Rhizobium symbiosis.

[Streptomyces species identification using the computer program StmID].

Systematic position of 49 cultures from Ukrainian Collection of Microorganisms (UCM) has been revised using the computer program StmID. Forty five cultures retained their species status but 4 cultures received the new species. Authors make a critical estimate of the program work and propose some recommendations for users.

[About the past and present of the Department of General and Soil Microbiology and ... something else]. / O proshlom i nastoiashchem otdela obshchei i pochvennoi mikrobiologii i ... eshche koe o chem.

A historical essay of creative path of collective of the Department of General and Soil Microbiology, founded in 1928, is presented. Two research schools have been formed for the past years: ecophysiology of soil microflora and geochemical activity of microorganisms. L. I. Rubenchik stood at the sources of these schools. A problem of soil biology and microorganisms interrelations with higher plants occupies a considerable place in the Department research. Separate groups, microorganisms and microbe cenoses are studied as a whole as the complex self-regulated system. The investigations of microbe corrosion of metals initiated by a necessity to solve urgent problems of Kyiv metro have been formed as the priority trend. Agents and mechanisms of biological damages of the overground, underground and underwater structures are studied and the grounds of anticorrosion measures are developed within the framework of these trends.

[The molecular-weight characteristics of the bacterial lectins and humus components in soil]. / Molekuliarno-massovye kharakteristiki bakterial'nykh lektinov i gumusovykh komponentov pochvy.

A method has been developed to determine the molecular-weight distribution of biologically active substances: bacterial lectins and soil humus compounds. The method based on the simultaneous centrifugation of samples and molecular weight standards in the density gradient of NaCl solutions or combined gradient of NaCl and CsCl solutions permits analysing biologically active substances: lectins, proteins, polysaccharides, protein-polysaccharide complexes, humus compounds in the interval of molecular weight of 13.7 kappa [symbol: see text] a to 2000 kappa [symbol: see text] a. The use of this method in the soil researches makes it possible to study the dynamics of change of molecular parameters of the soil organic matter depending on agrotechnical methods as well as to determine transformation regularities of microbial polysaccharides.

[The homeostasis of the microbial communities in soils polluted by heavy metals]. / Gomeostaz mikrobnykh soobshchestv pochv, zagriaznennykh tiazhelymi metallami.

Homeostatic potentialities of microbial communities in soils contaminated with heavy metals have been studied. To estimate the effect of contaminants on the soil microflora it was proposed to use the indices characterizing homeostasis of microbial community: microorganism survivability in contaminated soil and the period of restoration of their number, sensitivity to certain contaminants. In the model experiments on dark-grey podzolized soil it was shown that contamination with heavy metals (Cu2+, Cd2+, Sr2+, Pb2+, Hg2+) in the doses of 2 and 4 maximum permissible concentrations provokes a short-term inhibition of microorganisms development after which their number restores. Introduction of the mixture of metals evokes more intensive inhibition and extends the period of microorganism number restoration as compared with the effect of certain metals in the same doses.