ABSTRACT
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Here, we present the draft genome sequence of Magnetospirillum sp. strain SO-1, a freshwater magnetotactic spirillum isolated from the sediments of the Ol'khovka River, Russia.
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According to 16S rRNA gene- or genome-based phylogeny, magnetotactic bacteria (MTB) belong to diverse taxonomic groups. Here we analyzed the diversity of MTB in a sample taken from the freshwater lake Beloe Bordukovskoe near Moscow,... more
According to 16S rRNA gene- or genome-based phylogeny, magnetotactic bacteria (MTB) belong to diverse taxonomic groups. Here we analyzed the diversity of MTB in a sample taken from the freshwater lake Beloe Bordukovskoe near Moscow, Russia, by using molecular identification based on sequencing of the 16S rRNA gene andmamK, a specific marker gene for these bacteria. A protein encoded by themamKgene is involved in magnetosome chain arrangement inside the cell. As a result, six operational taxonomic units (OTUs) of MTB were identified. Among them, OTUs affiliated with the phylumNitrospiraewere predominant. ‘Ca. Etaproteobacteria’ andAlphaproteobacteriarepresented the minor groups of MTB. We also identified a novel MTB belonging to the familySyntrophaceaeof theDeltaproteobacteriaclass. Using a combination of fluorescence and transmission electron microscopy, the bacteria belonging to these new MTB groups were visualized. Electron microscopy revealed thatSyntrophaceaeMTB were rod-shaped ...
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Glutamate oxidase activity was studied in 1254 Streptomyces strains isolated from the zonal soils of various regions of Russia and other countries. Seven strains proved to be producers of extracellular L-glutamate oxidase. The most active... more
Glutamate oxidase activity was studied in 1254 Streptomyces strains isolated from the zonal soils of various regions of Russia and other countries. Seven strains proved to be producers of extracellular L-glutamate oxidase. The most active producer strain was identified, and the conditions of enzyme biosynthesis were optimized. A multistep-mutagenesis and selection procedure allowed a genetically stable strain, Streptomyces sp. Z-11-6, to be obtained, whose glutamate oxidase activity was 40 times higher than that of the original natural isolate.
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Using the method of enrichment cultures, eight lactate oxidase producer strains of the fungus Geotrichum candidum were identified. The microorganisms were isolated from diverse specimens of fermented vegetables and manure. Variation in... more
Using the method of enrichment cultures, eight lactate oxidase producer strains of the fungus Geotrichum candidum were identified. The microorganisms were isolated from diverse specimens of fermented vegetables and manure. Variation in the content of glucose and lactate and the degree of aeration made it possible to attain lactate oxidase activities of up to 130-140 U per 11 grown medium containing microbial cells.
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Species composition of anoxygenic phototrophic bacteria in microbial mats of the Goryachinsk thermal spring was investigated along the temperature gradient. The spring belonging to nitrogenous alkaline hydrotherms is located at the shore... more
Species composition of anoxygenic phototrophic bacteria in microbial mats of the Goryachinsk thermal spring was investigated along the temperature gradient. The spring belonging to nitrogenous alkaline hydrotherms is located at the shore of Lake Baikal 188 km north-east from Ulan-Ude. The water is of the sulfate-sodium type, contains trace amounts of sulfide, salinity does not exceed 0.64 g/L, pH 9.5. The temperature at the outlet of the spring may reach 54 degrees C. The cultures of filamentous anoxygenic phototrophic bacteria, nonsulfur and sulfur purple bacteria, and aerobic anoxygenic phototrophic bacteria were identified using the pufLM molecular marker. The fmoA marker was used for identification of green sulfur bacteria. Filamentous cyanobacteria predominated in the mats, with anoxygenic phototrophs comprising a minor component of the phototrophic communities. Thermophilic bacteria Chloroflexus aurantiacus were detected irn the samples from both the thermophilic and mesophili...
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Microbial methanogenesis at extreme conditions of saline alkaline soda lakes has, so far, been poorly investigated. Despite the obvious domination of sulfidogenesis as the therminal anaerobic process in hypersaline soda lakes of Kulunda... more
Microbial methanogenesis at extreme conditions of saline alkaline soda lakes has, so far, been poorly investigated. Despite the obvious domination of sulfidogenesis as the therminal anaerobic process in hypersaline soda lakes of Kulunda Steppe (Altai, south-western Siberia), high concentrations of methane were detected in the anaerobic sediments. Potential activity measurements with different substrates gave results significantly deviating from what is commonly found in hypersaline habitats with neutral pH. In particular, not only a non-competitive methylotrophic pathway was active, but also lithotrophic and, in some cases, even acetate-dependent methanogenesis was found to be present in hypersaline soda lake sediments. All three pathways were functioning exclusively within the alkaline pH range between 8 and 10.5, while the salt concentration was the key factor influencing the activity. Methylotrophic and, in less extent, lithotrophic methanogenesis, was active up to soda-saturatin...
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The properties of extracellular L-glutamate oxidase, isolated and purified from Streptomyces sp. Z-11-6 (specific activity, 50.8 U/mg protein; yield, 40%), were studied. A photometrical method of determination of activities of alanine-... more
The properties of extracellular L-glutamate oxidase, isolated and purified from Streptomyces sp. Z-11-6 (specific activity, 50.8 U/mg protein; yield, 40%), were studied. A photometrical method of determination of activities of alanine- and aspartate aminotransferases, based on the use of the L-glutamate oxidase and peroxidase, has been developed. This method is sufficiently sensitive to be used for the determination of aminotransferase activities in biological fluids. The presence of other amino acids did not interfere with the analysis and had no effect on the results of determination.
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A method for isolation of extracellular glucose oxidase from Penicillium funiculosum 433 and its purification is proposed. The enzymatic preparation was produced with a yield of 56% and a specific activity of 3730 AU per 1 mg protein. The... more
A method for isolation of extracellular glucose oxidase from Penicillium funiculosum 433 and its purification is proposed. The enzymatic preparation was produced with a yield of 56% and a specific activity of 3730 AU per 1 mg protein. The enzyme studied displayed a high thermostability, resistance to metal ions, and performance in a wide pH range and was equal in its properties to foreign analogues.
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A new enzymatic photometric assay for determination of methanol and ethanol in solutions containing both alcohols is described. The assay allows detecting methanol in the concentration range of tens ppm of in the presence of tens per cent... more
A new enzymatic photometric assay for determination of methanol and ethanol in solutions containing both alcohols is described. The assay allows detecting methanol in the concentration range of tens ppm of in the presence of tens per cent of ethanol. The lower determination threshold for methanol is at least 0.002% in the presence of 45% ethanol, with a coefficient of variation of 0.02-0.05. General-purpose spectrophotometers and photoelectric colorimeters can be used in the measurements.
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A novel enzymatic photometric assay for ethanol determination using alcohol oxidase and peroxidase is described. The sensitivity of the method allows detecting ethanol in biological fluids (saliva and blood serum). Secondary alcohols and... more
A novel enzymatic photometric assay for ethanol determination using alcohol oxidase and peroxidase is described. The sensitivity of the method allows detecting ethanol in biological fluids (saliva and blood serum). Secondary alcohols and other organic compounds do not interfere with the assay. General-purpose spectrophotometers and photoelectric colorimeters can be used in the measurements. Methanol and propanol can also be determined by this technique.
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ABSTRACT We present a test procedure and test results for purposes of approval of type for real-time polymerase chain reaction (PCR) amplifiers.
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The properties of extracellular L-glutamate oxidase isolated and purified from Streptomycessp. Z-11-6 (specific activity, 50.8 U/mg protein; yield, 40%) were studied. A photometric method of determination of activities of alanine and... more
The properties of extracellular L-glutamate oxidase isolated and purified from Streptomycessp. Z-11-6 (specific activity, 50.8 U/mg protein; yield, 40%) were studied. A photometric method of determination of activities of alanine and aspartate aminotransferases based on the use of L-glutamate oxidase and peroxidase has been developed. This method is sufficiently sensitive to be used for determining aminotransferase activities in biological fluids. The presence of other amino acids does not interfere with the analysis and has no effect on the results of determination.
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A method for isolation of extracellular glucose oxidase from Penicillium funiculosum 433 and its purification is proposed. The enzymatic preparation was produced with a yield of 56% and a specific activity of 3730 AU per 1 mg protein. The... more
A method for isolation of extracellular glucose oxidase from Penicillium funiculosum 433 and its purification is proposed. The enzymatic preparation was produced with a yield of 56% and a specific activity of 3730 AU per 1 mg protein. The enzyme studied displayed a high thermostability, resistance to metal ions, and performance in a wide pH range and was equal in