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PubMed1965

Ultra-high vacuum and microorganisms.

Experimental study of the space environment effect on living organisms is one of the most important tasks of exobiology. However location of the living organisms under study outside space vehicles and sputniks is combined with technical difficulties. Therefore it is much more suitable to reproduce conditions found in space in laboratory and to study its effect on living cells. It was proved that low temperatures, even those approaching absolute zero do not kill microorganisms. The fact of microorganisms surviving radiation of some million roentgen suggests that they would not be killed by ionizing radiation in space. UV rays should be considered as the most active sterilizing agent. The ability of microorganisms to resist high vacuum is studied much worse. Under the action of high vacuum at 10(-8)-10(-9) mm Hg during 72 hours all studied seven species of spore-forming bacilli remained viable. As for nonsporeforming bacteria under conditions mentioned, cells of some species perished (correction of parished) completely while other species retained viable cells. Conidia of fungi and parts of mycelium of fungi which do not form conidia, sustained high vacuum well.

Aspergillus fumigatus↗
PubMedDate not supplied

[Role of phenol-decomposing microorganisms in the process of phenol destruction in the Black Sea].

The number and species of phenol decomposing microorganisms, as well as the activity of their biochemical oxidation of phenol, were studied in waters of the shelf zone of the Black Sea, from the Danube estuary to Batumi. The number of these microorganisms and their phenol decomposing activity were higher in waters near harbours than in regions outside the anthropogenic activity. These parameters were highest in contaminated waters of the river origin. Most of these phenol decomposing microorganisms belong to the genera Pseudomonas and Bacterium, with the predominance of the species of Bacterium album and Pseudomonas desmolyticum (subspecis Pseudomonas rathionis).

Marine Biology↗
PubMed2002

Exposure to airborne microorganisms in furniture factories.

Microbiological air sampling was performed in 2 furniture factories located in eastern Poland. In one factory furniture were made from fibreboards and chipboards while in the other from beech wood. It was found that the concentration of total microorganisms (bacteria + fungi) in the air of the facility using beech wood for furniture production (mean 10.7 x (3) cfu/m(3), range 3.3 27.5 x (3) cfu/m(3)) was significantly higher (p < 0.01) compared to microbial concentration in the facility using fibre- and chipboards (mean 3.6 x (3) cfu/m(3), range 1.9-6.2 x (3) cfu/m(3)). On average, the commonest microorganisms in the air of the furniture factories were corynebacteria (Corynebacterium spp., Arthrobacter spp., Brevibacterium spp.) which formed 18.1-50.0% of the total airborne microflora, and fungi (mostly Aspergillus spp., Penicillium spp., Absidia spp. and yeasts) which formed 6.2-54.4% of the total count. The values of the respirable fraction of airborne microflora in the furniture factories varied within fairly wide limits and were between 15.0-62.4%. Altogether, 28 species or genera of bacteria and 12 species or genera of fungi were identified in the air of examined factories, of which respectively 8 and 7 species or genera were reported as having allergenic and/or immunotoxic properties. In conclusion, the workers of furniture factories are exposed to relatively low concentrations of airborne microorganisms which do not exceed the suggested occupational exposure limits. Nevertheless, the presence of allergenic and/or immunotoxic microbial species in the air of factories poses a potential risk of respiratory disease, in particular in sensitive workers.

Absidia↗
PubMedDate not supplied

[Microorganism in the hyphae of mycorrhiza-forming fungus].

A microorganism with the cell wall and cytoplasmic membrane was found when the endotrophic mycorrhiza of pea was studied by electron microscopy. The wall of the microorganism was in a close contact with the cytoplasm of the fungus. No changes were found in the ultrastructure of the fungus and microorganism caused by their interaction.

Bacteria↗
PubMedDate not supplied

[Generation time of pure cultures of heterotrophic microorganisms isolated from Lake Baĭkal].

Generation time was determined in pure cultures of heterotrophic microorganisms in the conditions similar to those of Baikal in June--July of 1972. Generation time was found to be 37+/-7, 16+/-2.5, 16+/-3.2, and 10+/-2.5 hours, respectively, when the cultures had been diluted with Baikal water in the following rations: 1 : 0,1 : 5,1 : 10, and 1 : 20. No differences in the growth rate were found among 11 cultures of heterotrophic microorganisms isolated from Baikal. Conditions limiting the microbial growth improve from the dilution of 1 : 0 to the dilution of 1 : 5. The mean time of generation is 27 hours for June--July. Generation time determined for pure cultures of heterotrophic microorganisms in the conditions similar to natural can be used to calculate production of the bacterial biomass for a definite period of the year.

Bacteria↗
PubMed2002

Exposure to airborne microorganisms and endotoxin in a potato processing plant.

Microbiological air sampling was performed in a big potato processing plant located in eastern Poland. Air samples for determination of concentrations of microorganisms, dust and endotoxin were collected at 6 sites in the division producing potato flakes and meal from dried potato pulp and at 2 sites in the division producing potato syrup from imported starch. The concentrations of total airborne microorganisms were within a range of 28.3-93.1 x 10(3) cfu/m(3). Mesophilic bacteria were dominant at all sampling sites, forming 73.1-98.8% of the total count. Among them, distinctly prevailed corynebacteria (irregular Gram-positive rods) that accounted for 54.3-81.1% of the total airborne microflora. The most common were strains of Corynebacterium spp., followed by strains of Arthrobacter spp., Microbacterium spp., and Agromyces ramosus. The latter species, so far not reported from the air of occupational environments, abundantly develops in the parenchyma of potato tubers. Its airborne concentration increased rapidly after peeling of potatoes, and attained maximal values at cutting and blanching (steaming and sulfuration) of potatoes, and at sacking of potato meal. The proportions of Gram-negative bacteria and endospore-forming bacilli were low, respectively 0.6-7.6% and 2.0-8.1% of total count. Fungi constituted 1.2-26.9% of total count. The dominant species was Aspergillus niger that formed 99.8% of total airborne fungi. The values of the respirable fraction of airborne microflora varied between 25.3-73.2%. The concentrations of airborne dust were 1.4-26.6 mg/m(3) in the division producing potato flakes and meal and 114.9-200.5 mg/m(3) at pouring of potato and corn starch for syrup. The concentrations of airborne endotoxin were in the range of 0.011-0.089 microg/m(3) during the initial stages of potato processing (unloading, washing, peeling) and drastically increased after blanching to the extraordinarily high levels of 45.9-1893.9 microg/m(3). At pouring of starch for syrup, the concentrations of airborne endotoxin were much lower, within a range of 0.029-0.156 microg/m(3). In conclusion, the workers of potato processing facilities could be exposed to large concentrations of microorganisms, dust and endotoxin posing a risk of work-related respiratory disease.

Agricultural Workers' Diseases↗
PubMed2002

[Inflammatory bowel disease--do microorganisms play a role?].

This review focuses on the potential pathogenic role of microorganisms in relation to inflammatory bowel diseases, i.e. Crohn's disease and ulcerative colitis. Pathogenic microorganism such as Mycobacterium paratuberculosis, measles and mumps viruses, Epstein-Barr virus, and Listeria monocytogenes are discussed, as well as involvement of the normal intestinal flora. Furthermore, the influence of microorganisms in experimental animal colitis models is discussed. The available results are inconclusive, but there seems to be basis for proposing the hypothesis that the inflammation in inflammatory bowel disease reflects an immune imbalance with loss of tolerance for normally harmless antigens in the mucosal microflora.

Animals↗
PubMedDate not supplied

[Glycopolymers of microorganisms as a source for creation of ecologically-safe antimicrobial media with specific activity].

Current data concerning structure components of the surface of microorganisms which take direct part in manifestation of their adhesive properties--adhesin, on the one hand, and carbohydrate components of cell receptors, on the other hand, are presented and analyzed in the paper. The prevention or decrease of adhesion by means of competitive inhibition by substances, which enclose structure, analogues of adhesins or their receptors, make up promising trend in the system of treatment and prophylaxis of infectious diseases. The use of synthetic substance of directed action will allow ceasing the development of infectious process without additional chemical loading of the organism-host and pollution of the environment, since as to their structure they resemble biomolecules typical of this organism. It is asummed that the data on the microorganism surface components can serve a basis for conducting fundamental investigations concerning relations between the structure and function of natural biopolymers, specification of phylogenetic relations between certain groups of microorganisms as well as for defining the mechanisms of the action and further perfection of probiotics.

Adhesins, Bacterial↗
PubMed2002

[Diversity of the microorganisms degrading aromatic hydrocarbons].

Aromatic hydrocarbons are biological xenobiotics. Indigenous microorganism groups turn from being unfamiliar with into active response to environmental changes by their adaptability to environment. There are changes in their genetic background, and then, the biodiversity turns into being. This paper reviewed the microorganism groups resources, biocharacters, genetic background, evolvement and their adaptability to environment; described the genetic information, expression and regulatory for some species in detail; and pointed out that the degradation of aromatic hydrocarbons depended mainly on new microorganisms formed by genetic engineering and on their highly efficient metabolic regulatory.

Bacteria↗
PubMedDate not supplied

[Microorganisms in heat supply lines and internal corrosion of steel pipes].

In laboratory experiments with batch cultures of thermophilic microorganisms isolated from urban heat supply systems, the growth of sulfate-reducing, iron-oxidizing, and iron-reducing bacteria was found to accelerate the corrosion rate of the steel-3 plates used in the pipelines. In the absence of bacteria and dissolved oxygen, minimal, corrosion was determined. The aforementioned microorganisms, as well as sulfur-oxidizing bacteria, were found to be widespread in water and corrosion deposits in low-alloy steel pipelines (both delivery and return) of the Moscow heat networks, as well as in the corrosion deposits on the steel-3 plates in a testing unit supplied with the network water. The microorganisms were found in samples with water pH ranging from 8.1 to 9.6 and a temperature lower than 90 degrees C. Magnetite, lepidocrocite, goethite, X-ray amorphous ferric oxide were the corrosion products identified on the steel-3 plates, as well as siderite, aragonite, and S0. The effect of microbiological processes on the rate of electrochemical corrosion was evaluated from the accumulation of corrosion deposits and from variation in total and local corrosion of the steel plates in a testing unit.

Bacteria↗
PubMedDate not supplied

[Department of Biochemistry of Microorganisms--start of the path (1951-1973)].

Creation of the Department of Biochemistry of Microorganisms at the Institute of Microbiology and Virology of the Academy of Sciences of Ukrainian SSR in the 30's of the last century was determined by a necessity of profound investigation of vital activity biochemism of microorganisms from various systematic groups which were studied in microbiological department of the Institute. Such complexity can explain certain diversity of the Department research at initial stages of its existence. The research of saccharose transformation into dextran Leuconostoc mesenteroides, when production solutions become slingy at sugar-refinaries, was one of the first most significant works of the Department. The enzyme saccharose-glycosyl-transferase performing this process was described for the first time. A cycle of works on the study of enzymes splitting lactose in milk under the effect of Streptococcus lactis has been carried out. Complex investigation of a number of proteins, polysaccharides, enzymes in enterobacteria has shown that the blocking of the enzyme aldolase is one of the reasons of alkali formation. A method has been developed for isolation of arenarin, antibiotic of plant origin, from sandy everlasting, the nature of its acting basis has been established. Nufarin, an active antibiotic, was isolated from the roots of white water lily when studying nitrogen fixation processes, special attention was given to interaction of hydrogenase and enzymes, taking part in nitrogen fixation, to the effect of ATP on these processes, ways of its synthesis, localization of ATPase in the cell membranes. Works on the study of lypopolysaccharides and polysaccharides of Gram-negative enterobacteria, bacteria of Pseudomonas genus were started with the purpose to use the obtained data to specify systematic propositions of the investigated microorganisms. Further on these works became the basis of thematic department. There are numerous reviews dedicated to their development.

Academies and Institutes↗
PubMedDate not supplied

[Taxonomy, ecology, and physiological and biochemical characteristics of industrially important microorganisms].

The work is dedicated to the investigations which were carried out in the Department of Physiology of Industrial Microorganisms in the recent years. Fundamental results of investigations dedicated to development of systematics of nocardio- and coryne-like bacteria, lactic acid bacteria and yeast; to the study of their distribution in nature, physiological-and-biochemical peculiarities. Considerable attention is paid to growth physiology of lactic acid bacteria and yeast, to lectin-forming microorganisms, to the study of fungi shaping under deep cultivation, as well as to microorganisms, taking part in the environment purification from heavy metals and oil products. Drugs created for treatment and prophylaxis of cattle diseases, for fodder siloing; new lactic acid preparations of functional direction, technological bases of sewage treatment for oil products and heavy metals are described.

Academies and Institutes↗
PubMed2003

[Advances in extraction and purification of soil microorganism].

For the studies on soil microbial ecology and bio-diversity as well as on the dynamics of C, N, S and P in soil, it is necessary to quantitatively extract microorganism from soil. The recent advances on extraction and purification of microorganism from soil were reviewed in this paper. The procedure for extracting microorganism from soil was comprised of three steps, i.e., soil dispersion, separation and purification. Most bacteria in soil could be successively extracted from soil particles by present techniques such as filtration, centrifugation and elutriation. However, filamentous fungi seem more difficult to be extracted than bacteria, because it is tangled with soil particles. Rotating wire frame, aqueous extraction and membrane filter technique, and low-speed centrifugation were used for extracting filamentous fungi from soil, but the extraction efficiency was rather low and needed to be raised. Aqueous two-phase partitioning system was successfully adopted as a technique for bacteria purification, and it would possibly become a technique suitable for fungi purification. The potential area of research on soil microbial ecology as well as on soil and plant nutrition by using microbial extraction technique was also discussed.

Bacteria↗
PubMedDate not supplied

[Cultivation of microorganisms in micro-volumes of culture media].

Studies on the cultivation of aerobic microorganisms in microdrops of growth medium, immobilized in a layer of highly dispersed disconnector (Aerosil), were carried out. The dispersion of the growth medium and its immobilization in a layer of Aerosil was found to produce no influence on the morphological, cultural and biochemical properties of Serratia marcescens cells, determined both immediately after treatment with the field and some time after storage of the treated suspensions. On the contrary, the duration of the action of ferromagnetic bodies produced essential influence on the viability of the microorganisms in dispersed growth medium and on the accumulation of cells in the course of subsequent cultivation. The development of cells grown in the microdrops of the nutriuent medium was similar to that of cells grown in submerged cultivation, following the S-shaped curve. With the increase of the seed dose a drop in the initial growth rate occurred and the accumulation of microbial cells increased by the end of the process. The greatest increase of biomass was observed with minimal seed doses. With a rise in the concentration of amino nitrogen in the growth medium the yield of cells increased only till this concentration reached 320 mg%. Under these conditions the specific growth rate also increased. The accumulation of cells was greater and occurred earlier when microorganisms were cultivated in immobilized state in powder.

Bacteriological Techniques↗
PubMed2003

[Advances in the research of soil microorganisms and their mediated processes under heavy metal stress].

More and more evidence from both laboratory and field experiments suggested that soil microbes were more sensitive to heavy metal stress than soil animals or plants living in the same soil. This understanding has been gradually accepted as a common point in this field. The history and the latest advances in soil microorganisms and its mediated processes under heavy metal stresses in soils were reviewed in this paper. It is difficult to do any comparison among the results from laboratory, field toxicological experiment and environmental monitoring. So far, a relevantly 'accurate' control soil was rarely available in the environmental monitoring. Much of evidence has indicated that not only microbial population/biomass was changed under heavy metal stress, but also its structure was varied. Although many molecular methods, such as PLFA, BIOLOG and DNA, have been developed to detect this microbial structural change, they always need many expensive instruments and accessories, and only could be done in laboratory. Therefore, some rapid and easy methods are expected to develop to substitute the traditional plate count. The speciation in the solution phase, ion effect and rhizospheric effect of heavy metal on the toxicity to soil microorganisms and its mediated processes need extent studies and discussion. Finally, the microbial indicator system of assessing heavy metal toxicity to soil microorganisms and its mediated processes need to be established.

Bacteria↗
PubMed2003

Influence of air-ions on selected microorganisms.

In the following work the influence of air-ions and ozone on the selected microorganisms, first of all on Staphylococcus epidermidis is discussed. Carried out investigations proved that the levels of air-ions concentrations, causing specific changes in the development of particular microorganisms, are very differentiated and depend on individual parameters of those organisms. These levels are generally characterized by high values of concentrations, range n +/- =4 x 10(6) ions/cm3 and are connected with the type of the air-ions used. However investigations did not confirm any negative influence of the positive air-ions seen as a destructive factor upon any of the investigated microorganisms.

Acanthamoeba↗
PubMed2003

[Analysis of the microorganisms isolated from kidney recipients treated in the Department of Clinical Transplantology and General Surgery, Medical University in Bydgoszcz in 2001 year].

One of the most important reasons of complications after organ transplantation may be the infections. The aim of the present work was to analyse of microorganisms isolated from patients, which were the recipients for kidney transplantation in 2001 year. The diagnostic material contained 140 samples from 53 patients, 40 (22.2%) samples from Euro-Collins fluid used for kidney storage before the transplantation and 3 end-pieces of catheter. The positive cultures were found in 125 (69.4%) samples. Gram-positive bacteria constituted 58.4%, Gram-negative bacteria--34.2%, fungi--7.4%. 140 strains of microorganisms were isolated from pharyngeal swabs and 55 strains of bacteria were isolated from palm swabs. Most of them were considered as a physiological flora. It was found 4-time significant bacteriuria among positive cultures from urine samples. In the cultures of fluid used for kidney storage 12 (30.0%) positive samples were obtained, out of which 16 strains of microorganisms were isolated. Among the strains of Staphylococcus 35.3% were MR. Among 18 strains of Gram-negative rods one strain was multiresistant to antibiotics. None of analyzed strains was ES beta L-producing. A high percentage of positive cultures from fluid used for kidney storage suggests the possibility of contamination of the organ with bacteria coming from kidney donor or during the storage, transport and actions connected with taking the organ to the transplantation.

Drug Resistance, Multiple↗
PubMedDate not supplied

[Manganese concentration by microorganisms inhabiting the soils of a manganese biogeochemical province in Georgia].

The concentrating of manganese by microorganisms was studied with bacteria, actinomycetes and fungi inhabiting soils of the manganese biogeochemical province of the Georgian Republic with different content of this element (from 1045 to 296 000 mg/kg of dry weight). The amount (from 4.0 X 10(-3) to 10 per cent per dry substance) and character of manganese accumulation by microorganisms were found to depend on the content of this element in the growth medium, the taxonomic position of microorganisms, and their adaptation to geochemical conditions.

Bacillus megaterium↗