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For accurate species-level identification of microorganisms, researchers today increasingly use a combination of standard microbiological cultivation and visual observation methods with molecular biological and genetic techniques that help distinguish between species and strains of microorganisms at the level of DNA or RNA molecules. The aim of this work was to identify microorganisms from the ICG SB RAS Collection using an integrated approach that involves a combination of various phenotypic and genotypic characteristics. Key molecular-genetic and phenotypic characteristics were determined for 93 microbial strains from the ICG SB RAS Collection. The strains were characterized by means of morphological, physiological, moleculargenetic, and mass-spectrometric parameters. Specific features of the growth of the strains on different media were determined, and cell morphology was evaluated. The strains were tested for the ability to utilize various substrates. The strains studied were found to significantly differ in their biochemical characteristics. Physiological characteristics of the strains from the collection were identified too, e. g., the relationship with oxygen, type of nutrition, suitable temperature and pH ranges, and NaCl tolerance. In this work, the microorganisms analyzed were combined into separate groups based on the similarities of their phenotypic characteristics. This categorization, after further refinement and expansion of the spectrum of taxa and their metabolic maps, may serve as the basis for the creation of an “artificial” classification that can be used as a key for simplified and quicker identification and recognition of microorganisms within both the ICG SB RAS Collection and other collections.

Genetic knowledge of microorganisms plays a critical role in the creation of new biotechnologies, since the effectiveness of any biotechnology is determined by the particular qualities of the structurally functional organization of molecular-genetic systems and their components used for the production of targeted products. Collections of microbial cultures play a decisive role in mobilizing biological resources and make it possible to form a solid base for genetic, molecular biological and biotechnological research. The aim of this work was to assess the key molecular-genetic and phenotypic characteristics of strains of the collection of microorganisms created in the “FRC Institute of Cytology and Genetics of the Siberian Branch of the Russian Academy of Sciences” as a genetic resource for biotechnology. Thirty strains of microorganisms of the collection were isolated by employees of the FRC ICG SB RAS from extreme natural ecosystems, the key molecular-genetic and phenotypic characteristics were described using modern methods of molecular biology and mass-spectrometry. DNA isolation and the sequencing of 16S rRNA gene sequences were performed. The strains of the collection were characterized by morphological, physiological, moleculargenetic and mass-spectrometric characteristics. The particular qualities of growing of strains on different substrates have been established, the study of cell morphology has been carried out. The physiological characteristics of the strains of the collection have been established: the attitude to oxygen, the type of nutrition, the range of temperature and pH, the attitude to NaCl and others. Different resistance of strains to antibiotics has been established. The creation of personal mass spectra of protein profiles of the studied strains of the collection was carried out. The resulting DNA sequences of the strains are deposited in the GenBank. The chemotaxonomic characteristics of strains have been determined. The biotechnological properties of the strains were assessed, the amount of metabolites (ethanol, lactic and acetic acids) in the culture liquid was determined. The value of the collection of microorganisms of the FRC ICG SB RAS as a genetic resource for biotechnology and bioengineering is determined not only by the species diversity of its strains, but also by a wide range of their area isolation and by the depth of their characterization using the widest arsenal of both classical and modern methods (including methods of genomics, proteomics, transcriptomics and bioinformatics).

Nonthermal effects of terahertz radiation on living objects are currently intensely studied, as more sources of this radiation type and devices employing it are being constructed. Terahertz radiation is increasingly used in security and inspection systems, medical and scientific appliances due to its low quant energy, which does not cause severe effects on organisms as other radiation types with higher quant energies do. The aim of this study was the identification of protein complexes participating in the response of the archaea Halorubrum saccharovorum H3 isolated from an extreme natural environment to terahertz radiation. We developed a microfluidic system for irradiation of bacterial and archaeal cultures with terahertz radiation and performed a 5-hour-long exposure of H. saccharovorum to terahertz radiation at a wavelength of 130 μm and a power density of 0.8 Wt per cm2 for 5 h. We identified under- or overexpressed proteins in response to terahertz radiation using 2D electrophoresis with subsequent MALDI-TOF mass spectrometry. A total of 16 differentially expressed protein fractions with at least 1.5-fold changes in expression level were detected. The obtained data suggest that Halorubrum cells respond to exposure to terahertz radiation by expression changes in gene products involved in translation regulation.

A new strain, Geobacillus stearothermophilus 22 was isolated from the Garga hot spring in the Bargusin Valley, Baikal Region, Russia. The morphology and biochemistry of the strain were analyzed, and the genomewide sequencing was conducted. The sequence was subjected to bioinformatic analysis. Nucleotide sequences (contigs) of the strain were found to be similar to the genome of the thermophilic strain G. kaustophilus Y412MC52. The proteome of the new strain was analyzed. Fragments associated with hemicellulases (endoxylanase, beta xylosidase, and arabinofuranosidase) and the endoxylanase enzyme were detected.

Rapid and accurate methods of microorganism identification are essential in various human activities. They include primarily clinical diagnostics. In addition, they are in demand in environment monitoring, harmacology, food industry, research, etc. There are diverse approaches to microbe identification: phenotyping, genotyping, chemotaxonomy, direct protein profiling, etc. In this work, the effects of various growth conditions, such as temperature, growth time, and nutrition medium, on the reproducibility of microbe identification by MALDI-TOF mass spectrometry are considered by the example of three Geobacillus stearothermоphilus strains.

We have studied properties of bacterial strains isolated from hot springs in the Northern Baikal region, Baikal Rift Zone, known to have a wide range of growth conditions (pH, temperature, and carbon sources). The phylogenetic analysis and microbiological studies show that thermophilic strains belonging to the Geobacillus stearothermophilus,Anoxybacillus flavithermus, and Thermoactinomyces vulgaris species express lipolytic activity. The isolated Geobacillus stearothermophilus strains grow at up to 70 °С in a wide pH range (5–10). The isolates of the Anoxybacillus genus can grow at 60–70 °С and рН ≤ 11. Thermoactinomyces vulgaris Gus-2-1 has a narrower growth condition range: 50–60 °С and рН 7–10. Of the strains with lipolytic activity isolated in this study, Geobacillus stearothermophilus is the most promising for further studies of secreted lipases.

The paper deals with the theoretical issues of biological oxidation of oil hydrocarbons from alkanes to polycyclic aromatics. We analyze the mechanisms of biochemical processes of decomposition of oil components and provide an overview of data from common databases. Studies of microbial communities of natural oil seeps in the Uzon caldera are described in detail. It is the first study of ecophysiological characteristics of oil-degrading microorganisms isolated from thermal oil seeps of the caldera.

The prospects of new alga strains as a source of non-food renewable biomass suitable for third generation biofuel production are discussed. West Siberia is of special interest, as it has a broad range of habitats and weakly studied microalga biodiversity. During this study, a number of strains were isolated. Of them, Chlorella spp. A1125 met the requirements for cultivation in a pilot-scale photobioreactor: high biomass productivity and high lipid content (0,081 g/l, or 23 % dry weight). The strain had high contents of saturated C16:0 (25 %) and unsaturated fatty acids: C16:2 (16 %) and C18:2 (27 %), thus being promising for catalytic production of third generation biofuel.

Introduction. When designing pipeline crossings for various purposes, the solution of many engineering problems is associated with the calculation of velocity distribution and estimation of hydraulic resistance created by them. Since it is very difficult to estimate the value of hydrodynamic resistance coefficients and lifting force by theoretical means, experimental studies are usually resorted to. Pipelines can be positioned in different ways in relation to the flow, and in practice pipelines are also buried in the bottom of the watercourse. In physical experiments, a partially buried pipeline is often modelled by truncating the buried section of the pipeline. This experimental setup is more suitable for a pipeline located in an impermeable bottom. In reality, erosion-prone bottoms are often porous and permeable.Materials and methods. Hydrodynamic forces acting on a pipeline with uneven depth on both sides, on a permeable bottom, are numerically studied. Two-dimensional Navier – Stokes equations averaged over Reynolds with k–e turbulence model are used to simulate fluid flow. The seepage flow at the permeable bottom is assumed to obey Darcy’s law, the Laplace equation is solved to calculate the pore pressure assuming an isotropic and homogeneous bottom. The flow structure and pressure distribution around the pipeline are considered. The ANSYS Fluent software package is used for numerical modelling.Results. It was found that the flow structure around the pipeline is asymmetric due to the difference in bottom levels on the two sides of the pipeline. The process of scouring of the sandy bottom in the area of the pipeline location was modelled in ANSYS Fluent. Comparison of calculation results at different flow rates was made. It was found that there is an obvious difference between the hydrodynamic forces experienced by the pipeline due to the asymmetric flow structure around the pipeline.Conclusions. Peak values of external forces and lift force decreasing as the value of depth into the bottom behind the pipeline increases (e2/D). The maximum error of the drag and lift forces calculated using sixth order Fourier series is about 4 %.