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S S Beliaev

Publications and source records attributed to S S Beliaev.

At least 19 recordsLinked to original sources
PubMedDate not supplied

[Physiologo-biochemical properties of a strain of Beijerinckia mobilis 1phi Phn+--a degrader of polycyclic aromatic hydrocarbons].

Beijerinckia mobilis 1f capable of degrading polycyclic aromatic hydrocarbons (PAHs) was isolated from a soil contaminated with creosote. Strain 1f could utilize phenanthrene and naphthalene as the sole sources of carbon. The mean rate of phenanthrene degradation during culture growth was 7-8 micrograms/(ml h). After cultivation under nonselective conditions, strain 1f retained its ability to degrade phenanthrene. Cometabolism considerably widened the range of PAHs that could be transformed by strain 1f. The strain was able to grow in a mineral medium with creosote as the sole source of carbon. After 30 days of cultivation in this medium, the total concentration of PAHs decreased from 665.5 mg/l to 170 mg/l.

Biodegradation, Environmental↗
PubMedDate not supplied

[Physiological and phylogenetic diversity of thermophilic spore-forming hydrocarbon-oxidizing bacteria from oil fields].

The distribution and population density of aerobic hydrocarbon-oxidizing bacteria in the high-temperature oil fields of Western Siberia, Kazakhstan, and China were studied. Seven strains of aerobic thermophilic spore-forming bacteria were isolated from the oil fields and studied by microbiological and molecular biological methods. Based on the 16S rRNA gene sequences, phenotypic characteristics, and the results of DNA-DNA hybridization, the taxonomic affiliation of the isolates was tentatively established. The strains were assigned to the first and fifth subgroups of the genus Bacillus on the phylogenetic branch of the gram-positive bacteria. Strains B and 421 were classified as B. licheniformis. Strains X and U, located between B. stearothermophilus and B. thermocatenulatus on the phylogenetic tree, and strains K, Sam, and 34, related but not identical to B. thermodenitrificans and B. thermoleovorans, undoubtedly represent two new species. Phylogenetically and metabolically related representatives of thermophilic bacilli were found to occur in geographically distant oil fields.

Bacillus↗
PubMedDate not supplied

[Clusterization of halophilic and halotolerant eubacteria using whole-cell protein electrophoresis data].

Total cell proteins of the nineteen halophilic and halotolerant eubacteria isolated from marine sediments and highly mineralized formation waters of oil fields were investigated by SDS gel electrophoresis. The microorganisms studied, phenotypically identified as belonging to the genera Dietzia, Rhodococcus, Staphylococcus, Cytophaga, Brevibacterium, and Archangium, were found to form clearly distinguishable clusters (20-30% similarity at the generic level) on the dendrogram derived from electrophoretic protein patterns. Protein similarity data confirmed the heterogeneity of Rhodococcus maris and its relatedness to the genus Dietza.

Bacterial Proteins↗
PubMedDate not supplied

[Microbiological processes in a high-temperature oil field].

Thermophilic sulfate-reducing bacteria (SRB) oxidizing lactate, butyrate, and C12-C16 n-alkanes of oil at a temperature of 90 degrees C were isolated from samples of water and oil originating from oil reservoirs of the White Tiger high-temperature oil field (Vietnam). At the same time, no thermophiles were detected in the injected seawater, which contained mesophilic microorganisms and was the site of low-temperature processes of sulfate reduction and methanogenesis. Thermophilic SRB were also found in samples of liquid taken from various engineering reservoirs used for oil storage, treatment, and transportation. These samples also contained mesophilic SRB, methanogens, aerobic oil-oxidizing bacteria, and heterotrophs. Rates of bacterial production of hydrogen sulfide varied from 0.11-2069.63 at 30 degrees C and from 1.18-173.86 at 70 degrees C micrograms S/(1 day); and those of methane production, varied from 58.4-100 629.8 nl CH4/(1 day) (at 30 degrees C). The sulfur isotopic compositions of sulfates contained in reservoir waters and of hydrogen sulfide of the accompanying gas indicate that bacterial sulfate reduction might be effective in the depth of the oil field.

Bacteria↗
PubMedDate not supplied

[Degradation of machine oil by nocardiform bacteria].

Gas liquid chromatography (GLC) was used for the first time to screen for machine oil-degrading microorganisms. Oil degradation was evaluated from the microorganism respiratory activity during the utilization of oil as the sole carbon and energy source. The results are consistent with those obtained by the conventional weighing method. Substrate specificity of the active strains with respect to different machine oils was studied. Bacterial communities exhibited the highest activity, whereas a Rhodococcus erythropolis strain was the most active among pure cultures. Various stages of bacterial interaction with oil drops were followed by means of fluorescent microscopy.

Actinomycetales↗
PubMedDate not supplied

[Desulfacinum subterraneum sp.nov.--a new thermophilic sulfate-reducing bacterium isolated from a high temperature oil field ].

A new thermophilic sulfate-reducing bacterium isolated from the high-temperature White Tiger oil field (Vietnam) is described. Cells of the bacterium are oval (0.4-0.6 by 0.6-1.8 microns), nonmotile, non-spore-forming, and gram-negative. Growth occurs at 45 to 65 degrees C (with an optimum at 60 degrees C) at NaCl concentrations of 0 to 50 g/l. In the course of sulfate reduction, the organism can utilize lactate, pyruvate, malate, fumarate, ethanol, salts of fatty acids (formate, acetate, propionate, butyrate, caproate, palmitate), yeast extract, alanine, serine, cysteine, and H2 + CO2 (autotrophically). In addition to sulfate, the bacterium can use sulfite, thiosulfate, and elemental sulfur as electron acceptors. In the absence of electron acceptors, the bacterium can ferment pyruvate and yeast extract (a yet unrecognized capacity of sulfate reducers) with the formation of acetate and H2. The G + C content of DNA is 60.8 mol %. The level of DNA-DNA hybridization of the isolate (strain 101T) and Desulfacinum infernum (strain B alpha G1T) is as low as 34%. Analysis of the nucleotide sequence of 16S rDNA places strain 101T in the phylogenetic cluster of the Desulfacinum species within the sulfate reducer subdivision of the delta subclass of Proteobacteria. All these results allowed the bacterium studied to be described as a new species, Desulfacinum subterraneum sp. nov., with strain 101 as the type strain.

Electron Transport↗
PubMedDate not supplied

[Effect of the media salinity on destruction of petroleum oils by nocardioform bacteria].

Oil degradation by cultures of Rhodococcus erythropolis and Dietzia maris was found to depend on the NaCl concentration in the medium. Optimal utilization of turbine oil by R. erythropolis and D. maris was observed at 0.5 and 2 to 5% NaCl concentration, respectively. Mineral oil and a mixture of paraffins (C14-C18) were utilized within a broader range of the medium salinity. As shown by fluorescent microscopy, D. maris colonies formed on the oil drop surface, whereas R. erythropolis cells penetrated the drops. The strains studied may populate various ecological niches in oil-containing ecosystems. They are promising for the development of microbial preparations for cleaning the environment from oil pollution.

Actinomycetales↗
PubMedDate not supplied

[Phylogenetic diversity of aerobic saprotrophic bacteria isolated from the Daqing oil field].

A diverse and active microbial community in the stratal waters of the Daqing oil field (China), which is exploited with the use of water-flooding, was found to contain aerobic chemoheterotrophic bacteria (including hydrocarbon-oxidizing ones) and anaerobic fermentative, sulfate-reducing, and methanogenic bacteria. The aerobic bacteria were most abundant in the near-bottom zones of injection wells. Twenty pure cultures of aerobic saprotrophic bacteria were isolated from the stratal waters. Under laboratory conditions, they grew at temperatures, pH, and salinity values typical of the stratal water from which they were isolated. These isolates were found to be able to utilize crude oil and a wide range of hydrocarbons, fatty acids, and alcohols. Phylogenetic analysis carried out with the use of complete 16S rRNA sequences showed that the isolates could be divided into three major groups: gram-positive bacteria with a high and a low G + C content of DNA and gram-negative bacteria of the gamma-subclass of the Proteobacteria. Gram-positive isolates belonged to the genera Bacillus, Brevibacillus, Rhodococcus, Dietzia, Kocuria, Gordonia, Cellulomonas, and Clavibacter. Gram-negative isolates belonged to the genera Pseudomonas and Acinetobacter. In their 16S rRNA sequences, many isolates were similar to the known microbial species and some probably represented new species.

Alcohols↗
PubMedDate not supplied

[Antagonistic interactions between stress factors during the growth of microorganisms under conditions simulating the parameters of their natural ecotopes].

Two stress factors, hypoxia (microaerobic conditions) and a high salt concentration, if applied simultaneously to aerobic microorganisms, display an antagonistic mode of interaction. As a result, the NaCl level that is usually optimal for moderate halophiles (5-6%) becomes optimal for the growth of weak halophiles (Rhodococcus erythropolis and Shewanella sp. CN32); the halotolerant yeast Yarrowia lypolytica acquires halophilic properties (with a growth optimum at a NaCl concentration of 10%), and the growth rate of the extremely halophilic Halobacterium salinarum increases at supraoptimal salt concentrations (25-34%). This phenomenon is apparently due to multiple changes in metabolic reactions. In particular, high salt concentrations suppress respiration and the formation of enzymes (superoxide dismutase and catalase) that protect the cell from toxic oxygen species. Therefore, establishment of microaerobic conditions compensates for the loss of these protective mechanisms and enables cell growth at higher salt concentrations than under aerobic conditions. Of some importance can also be the increase in the intracellular concentrations of osmoprotectants caused by the suppression of their intracellular oxidation. The implications of this phenomenon for the ecophysiology of microorganisms (including oiloxidizing species) and for the classification of weak and moderate halophiles are discussed.

Bacteria↗
PubMedDate not supplied

[Determination of the rate of microbiological oxidation of methane using 14CH4].

The rate of microbiological oxidation of methane was determined by a technique using 12CH4. About 75-96 percent of the carbon form the methane oxidized by microorganisms was found in carbon dioxide, the remaining part was incorporated into the microbial cells. The rate of microbiological mehtane oxidation in the water of the Mari lakes was 6.4 times 10(-3) to 464.4 times 10(-3) cm3 CH4/litre per day.

Bacteria↗
PubMedDate not supplied

[Intensity of bacterial methane formation in ooze deposits in lakes].

The rate of methane production of bacteria via the decomposition of acetate in ooze deposits of the Mari lakes was 0.0165 to 0.483 mg CH4/day/ litre wet ooze. From 32 to 98 per cent of methane in the ooze of studied reservoirs formed through microbiological reduction of carbon dioxide by hydrogen.

Acetates↗
PubMedDate not supplied

[Microbiological oxidation of methane in the stratal waters of the Lower Volgian].

Methanotrophic bacteria are rather widely distributed in bed waters of oil and gas deposits in the Nizhneye Povolzhye. Their number reaches 250 cells per 1 ml of water. However, bacterial methane oxidation is active only in waters whose redox potential exceeds +250 mV. In a number of cases, microbial methane oxidation is limited by the absence of oxygen from bed waters. If air is added to samples of such water, methane dissolved in the water is oxidized by microorganisms at a high rate (2--451 X 10(-4) cm3 of methane per litre of water per day).

Geological Phenomena↗