Search

The article deals with the initial period of modern development of Sunday school as one of the elements of the religious education system, restored by the Russian Orthodox Church. Based on the materials of legislation, periodicals, as well as oral sources (memoirs of participants of the events), the course of this process in the Rostov region in the 1990s and 2000s is restored. Data on the number of Sunday schools in dynamics are given. It is concluded that during the period of the patriarchate of Aleksiy II (Ridiger) (1990-2008), requirements for a modern Sunday school and local church administrative structures for the organization of educational activities were formed. Methodological base for Sunday schools and the training of catechists also began to be formed with the participation of regions (including the Rostov region) during this period.

Abstract 2-Oxoacids are involved in a number of important metabolic processes and can be used as biomarkers in some human diseases. A new optimized method for quantification of 2,4-dinitrophenylhydrazine derivatives of 2-oxoacids using high-performance liquid chromatography was developed based on available techniques for quantification of 2-oxoacids in mammalian brain. The use of the 2,4-dinitrophenylhydrazine derivatives of 2-oxoacids was shown to be more advantageous in comparison with the previously used phenylhydrazine derivatives, due to a high chemical stability of the former. Here, we determined the concentrations of pyruvate, glyoxylate, 2-oxoglutarate, 2-oxomalonate, and 4-methylthio-2-oxobutyrate in the methanol/acetic acid extracts of the rat brain using the developed method, as well discussed the procedures for the sample preparation in analysis of mammalian brain extracts. The validation parameters of the method demonstrated that the quantification limits for each of the analyzed of 2-oxoacids was 2 nmol/mg tissue. The developed method facilitates identification of subtle changes in the tissue and cellular content of 2-oxoacids as (patho)physiological biomarkers of metabolism in mammalian tissues.

The article reflects the results of the analysis of legislation and archive documents in the 1860-1880s, which made it possible to link the change in the number of “free schoolsˮ at churches (parish or parochial schools) of the Don diocese with certain changes in the national and regional policy, both directly aimed at the primary education system and indirectly affecting its development. A short-lived increase in the number of “free schoolsˮ at churches in the early 1860s coincides with the increasing administrative pressure on the clergy by the church authorities, who, following the secular authorities, obliged the clergy to organize schools for the children of parishioners. The reduction in the number of parochial schools from 1863 until their almost complete disappearance by the end of the 1870s was the result, first of all, of the activity of the Don Cossaсk Host, as well as the weakening of the requirements for the clergy from the church hierarchs regarding their participation in the organization of “free schoolsˮ. The clergy, burdened with numerous extra-liturgical duties and not receiving regular financial support, hardly carried out the organization of schools at churches. It is also shown that parish schools received impulses for development during the reign of Alexander III, and since 1884 the number of parish schools in the Don diocese began to grow again.

The analysis of the collapses of buildings and structures that have occurred in recent decades, as well as the results of experimental studies, shows that a sudden failure of a column of the load-bearing system of a building leads to dynamic effect on structures adjacent to the site of initial local destruction. In this case, the columns adjacent to the site of the initial local destruction can be subjected to the simultaneous action of the axial shock loading and the lateral displacement of the support nodes. In this regard, the subject of the paper is the dynamic behavior of a reinforced concrete column under axial-lateral impact. The paper proposes an analytical solution to the differential equation of the axial-lateral buckling of a reinforced concrete column under accidental impact caused by a sudden structural transformation of the load-bearing system. Nonlinear behavior of material and energy dissipation due to damping have been considered. As a criterion for the bearing capacity assessment, the achievement of zero resistance is accepted, i.e., the ability of cross-section to resist the increment of forces along the height of the column. The results of numerical modeling are compared with the experimental data for lateral displacement obtained by the authors for the model of a two-story reinforced concrete frame with slender columns. The obtained analytical solution allows approximate evaluation the progressive collapse behavior of eccentrically compressed reinforced concrete columns.

Biochemistry (Moscow) 86(2), 230 - 240 (2021). doi:10.1134/S0006297921020115, Potato virus A (PVA) protein coat contains on its surface partially unstructured N-terminal domain of the viral coat protein (CP), whose structural and functional characteristics are important for understanding the mechanism of plant infection with this virus. In this work, we investigated the properties and the structure of intact PVA and partially trypsinized PVA��32 virions using small-angle X-ray scattering (SAXS) and complimentary methods. It was shown that after the removal of 32 N-terminal amino acids of the CP, the virion did not disintegrate and remained compact, but the helical pitch of the CP packing changed. To determine the nature of these changes, we performed ab initio modeling, including the multiphase procedure, with the geometric bodies (helices) and restoration of the PVA structure in solution using available high-resolution structures of the homologous CP from the PVY potyvirus, based on the SAXS data. As a result, for the first time, a low-resolution structure of the filamentous PVA virus, both intact and partially degraded, was elucidated under conditions close to natural. The far-UV circular dichroism spectra of the PVA and PVA��32 samples differed significantly in the amplitude and position of the main negative maximum. The extent of thermal denaturation of these samples in the temperature range of 20-55��C was also different. The data of transmission electron microscopy showed that the PVA��32 virions were mostly rod-shaped, in contrast to the flexible filamentous particles typical of the intact virus, which correlated well with the SAXS results. In general, structural analysis indicates an importance of the CP N-terminal domain for the vital functions of PVA, which can be used to develop a strategy for combating this plant pathogen., Published by Springer Science + Business Media B.V, Dordrecht [u.a.]

During the entire life cycle, the facilities are experienced to force and environmental actions of various nature and intensity. In some cases, such influences can lead to a loss of the bearing capacity of the structural elements of a building, which in turn can lead to a disproportionate failure of the entire structural system. Such phenomenon was called progressive collapse. Major accidents at facilities, such as the collapse of a section of the Ronan Point high-rise residential building (London, 1968), the Sampoong department store (Seoul, 1995), the Transvaal Park pavement (Moscow, 2004), the World Trade Center (New York, 2011) and others, clearly demonstrated the urgency of this problem. In this regard, the regulatory documents of the USA, Great Britain, EU, China, Australia, Russia and other countries established requirements for the need to calculate structural systems of buildings for resist to progressive collapse after sudden localized structural damage. However, the steady increase in the number of new publications on the problem of progressive collapse observed in the world scientific literature indicates that the results of such studies do not yet provide exhaustive answers to all questions related to this phenomenon. In this regard, the proposed review article is aimed at systematizing, generalizing and analyzing new research results on resistance to progressive collapse of facilities, identifying new trends and proposing new research directions and tasks to improve the level of structural safety of design solutions for buildings and structures. In order to achieve this goal, the following aspects were considered: the nature of the impacts leading to progressive collapse; features of modeling the progressive collapse of structural systems of buildings and structures; mechanisms of resistance to progressive collapse and criteria for evaluation of a progressive collapse resistance. Particular attention in the scientific review is paid to the analysis of works related to a new direction of research in the area under consideration, associated with the assessment of the bearing capacity of eccentrically compressed elements of structural systems, the effect on their resistance to progressive collapse of the parameters of the loading mode, degradation of material properties and the topology of the structural system. The significance of the proposed scientific review is that, along with the well-known and new results presented in the English-language scientific literature, it summarizes and analyzes the original approaches, methods and research results published in Russian-language scientific publications, primarily included in the RSCI Web of Science.

The article demonstrates the possibility of prescribing an effective and safe lipid-lowering combination of the most tolerated doses of statins in combination with ezetimibe, using the example of a patient with severe lipid metabolism disorders in the post-infarction period. It has been shown that in real clinical practice, patients with acute coronary syndrome and persisting high LDL values are quite common, despite of the prescription of statins. These patients need closer follow-up and wider use of combined lipid-lowering therapy by adding ezetimibe to maximally tolerated doses of statins. Current clinical guidelines allow this to be done when patients fail to achieve target LDL values (>1.4 mmol/L) with statins monotherapy. This approach is effective and safe, which is illustrated by this hereditary clinical case. In routine clinical practice mandatory lipids control is required 4–6 weeks after patient’s discharge from the hospital for acute coronary syndrome. If the target lipids values were not achieved with the maximum dosage of statins, a mandatory using the combination therapy with ezetimibe is required. Keywords: myocardial infarction, dyslipidemia, improved prognosis, statins, ezetimibe For citation: Sedykh DYu, Fedorova NV, Kashtalap VV. Possibilities of combination lipid-lowering therapy in a patient with very high cardiovascular risk (сlinical case). Consilium Medicum. 2021; 23 (1): 70–73. DOI: 10.26442/20751753.2021.1.200604

The settlements and cemeteries of the Sintashta – type (21st–18th century BC) are concentrated in the southern Trans-Urals steppe. The earliest stage of investigations was related to the decoding of aerial photos that allowed specialists to discover and identify the majority of the settlements. This report presents the results of a geophysical investigation at the Andreevskoye settlement, where we conducted micro-magnetic and ground penetrating radar (GPR) surveys. Magnetic studies have provided new information on the structure of the fortifications and the number and location of houses in the settlements during their occupancy, as well as on the many wells discovered inside the houses. Drawing on our data, a new plan of the settlement was produced, more accurate than the one prepared solely from interpretations of aerial photographs. The settlement consists of multiple layers and is characterized by a complex configuration formed from three rectangular systems of defensive structures. We obtained GPR deep sections along three profiles, indicating the ditches and dwellings of the ancient settlement under sediments and the ruins of walls. Based on these data, we conclude that the depth from the modern surface of the earth to the occupation layer in the dwellings of the ancient settlement is approximately 50–70 cm. Our results provide archaeologists with reliable data that are necessary for the selection of excavation sites.

Introduction. Problem solving focused on the protection of buildings and structures from progressive collapse and minimization of resources, needed for this purpose, is becoming increasingly important. In many countries, including Russia, this type of protection is incorporated into national regulatory documents, and, therefore, any research, aimed at developing effective ways to protect structural systems from progressive collapse under special actions, is particularly relevant. In this regard, the present article aims to formulate effective strength criteria for such anisotropic materials as reinforced concrete to analyze plane stressed reinforced concrete structures exposed to sudden structural transformations caused by the removal of one of bearing elements. Materials and methods. To solve this problem, a variant of the generalized theory of plasticity of concrete and reinforced concrete, developed by G.A. Geniev, is proposed for application to the case of variable loading of a plane stressed reinforced concrete element. The acceptability of generalization of the strength criterion, pursuant to the theory of plasticity of concrete and reinforced concrete under static loading, and the applicability of this criterion to variable static-dynamic loading of reinforced concrete are used as the main hypothesis. An algorithm of an approximate method is presented as a solution to this problem; it allows to analyze the considered stress-strain state of plane stressed reinforced concrete elements. Results. The numerical analysis of the obtained solution, compared with the results of the experimental studies, was used to evaluate the designed strength criterion for reinforced concrete elements located in the area where the column is connected to the girder of a monolithic reinforced concrete frame in case of a sudden restructuring of a structural system. It is found out that the qualitative nature of the destruction pattern of the area under research, obtained in experiments, corresponds to the destruction pattern, identified by virtue of the analysis performed using the proposed criterion. Conclusions. The variant of the reinforced concrete strength criterion designated for the variable loading of a plane stressed reinforced concrete element and an algorithm for its implementation, based on the theory of plasticity of concrete and reinforced concrete developed by G.A. Geniev, is applicable to the analysis of a special limit state of reinforced concrete elements of structural systems of frames of buildings and structures.

The history of reindeer domestication is a critical topic in the study of human-animal relationships across Northern Eurasia. The Iamal-Nenets region of Arctic Siberia, now a global centre of reindeer pastoralism, has been the subject of much recent research on reindeer domestication. However, tracking the beginnings of reindeer domestication in this region and elsewhere in Eurasia has proved challenging. Archaeological imagery is an under-utilized source of information for exploring animal domestication. In this paper we explore the abundant reindeer imagery found at the Iron Age site of Ust’-Polui in Iamal, dating from ~260 bce to ce 140. While reindeer were hunted in Siberia long before the occupation of Ust’-Polui, portable reindeer imagery appears abruptly at this time period, co-occurring at the site with equipment thought to be for training transport reindeer. Training and working with transport reindeer required long-term engagement with specific animals that became well known and precious to their human keepers. Creating, utilizing and depositing the reindeer imagery objects at Ust’-Polui was a way of acknowledging critical new working relationships with specific domestic reindeer.

The study of reindeer domestication provides a unique opportunity to examine how domestication involves more than bodily changes in animals produced through selection. Domestication requires enskilment among humans and animals, and this process of pragmatic learning is dependent on specific forms of material culture. Particularly with the domestication of working animals, the use of such material culture may predate phenotypic and genetic changes produced through selective breeding. The Iamal region of Arctic Siberia is generating an increasingly diverse set of archeological data for reindeer domestication that evidences such processes. Three early sites, Ust’-Polui, Tiutei-Sale I, and Iarte VI, contain artifacts proposed to be parts of headgear worn by transport reindeer, the earliest dating to just over 2000 years ago. Contemporary Nenets reindeer herders scrutinized replicas of these archeological objects, and comparisons with historic reindeer harness parts from Arctic Russia were also made. Nenets consistently interpreted barbed L-shaped antler pieces from Iamal as parts of headgear for training young reindeer in pulling sleds. Some types of swivels were also interpreted as transport reindeer headgear. Based on these consultations with Nenets and observations of their ongoing reindeer domestication practices, we argue that material things such as headgear, harnesses, and sleds are not merely technological means of using or controlling reindeer in transportation but instead were part of the meshwork within which some reindeer became enskilled to being domestic. Domestication of reindeer and other animals involves ongoing efforts, landscapes, and made things, all of which form the environment within which domestic relationships emerge.

Small-angle X-ray scattering is an important structural tool for studying biological membranes; however, interpretation of scattering data remains a challenging problem. In most cases, analysis makes it possible to determine some structural parameters and the electron density profile of lipid bilayers, but no methods providing more detailed information (e.g., about the structural organization of vesicles) have been proposed yet. An approach making it possible to determine the main integral characteristics of liposomes using small-angle scattering is presented in this study. Within this approach a quasi-atomic model of liposome is built from individual lipid molecules, which form a sphere or a hollow ellipsoid. The method has been implemented in a computer program, verified on experimental small-angle X-ray scattering data, and proposed to analyze the structure of lipid vesicles and their interactions with proteins.

Small-angle X-ray scattering (SAXS) is one of the major tools for the study of model membranes, but interpretation of the scattering data remains non-trivial. Current approaches allow the extraction of some structural parameters and the electron density profile of lipid bilayers. Here it is demonstrated that parametric modelling can be employed to determine the polydispersity of spherical or ellipsoidal vesicles and describe the electron density profile across the lipid bilayer. This approach is implemented in the computer program BILMIX. BILMIX delivers a description of the electron density of a lipid bilayer from SAXS data and simultaneously generates the corresponding size distribution of the unilamellar lipid vesicles.

During operation, both of a residual static and dynamic load can be applied to the structural members, and in the case of an emergency impact, such as the sudden structural member removal, the dynamic additional loading arises in the structural elements. Ultimate deformations and strength of concrete and reinforced concrete under this loading mode significantly differ from their values under static or dynamic loading mode. This paper presents the results of experimental and theoretical determination of the concrete stress–strain curve parameters for varying levels of the initial static load and loading modes. The differential equation of the concrete deformation model for the static-dynamic loading mode and its solution at various levels of the initial static stress were obtained. It was established that the maximum permissible time of impact on a concrete specimen under dynamic additional loading and the ultimate strength of concrete depend on the level of the initial static load. Numerical analysis and specimens’ tests shown that parameters of the concrete stress–strain curves under static-dynamic loading mode substantially depend on the level of initial relative stresses in concrete.

In the Southern Urals in 2015–2019 research was conducted on the fortified settlement of the Bronze Age Levoberezhnoe (Sintashta II). An asphalt road was drawn through the settlement, during the construction of which about a third of the monument’s area was destroyed. Excavations of the monument have been carried out since 2015. It has been established that the settlement is multi-layered; it functioned in the Late Bronze Age from the turn of the 3rd–2nd millennium BC until the last quarter of the second millennium BC. Detailed magnetic and topographic surveys were performed on the territory that remaining survived the construction of the road. The location of the external moat was reliably determined by linear positive magnetic anomalies. The base of the outer wall of the settlement had a thickness of about 4 m, the width of the outer moat was 2–2.5 m. It was also possible to accurately localize a number of walls of buildings. The settlement had a rectangular shape, inside there were 26 dwellings. As a result of a comprehensive analysis of the data and aerial photographs of the last century, the layout of the entire settlement was reconstructed.

Recent studies demonstrate the involvement of inflammatory processes in the development of depression and the anti-inflammatory effects of antidepressants. Infiltration and adhesion of neutrophils to nerve tissues and their aggressive secretion are considered as possible causes of inflammatory processes in depression. We studied the effect of the antidepressant imipramine on the adhesion and accompanied secretion of neutrophils under control conditions and in the presence of lipopolysaccharides (LPS). As a model of integrin-dependent neutrophil infiltration into tissues, we used integrin-dependent adhesion of neutrophils to the fibronectin-coated substrate. We studied the effect of the antidepressant imipramine on the adhesion of neutrophils to fibronectin and the accompanying production of reactive oxygen species (ROS) and the secretion of proteins and free amino acids under control conditions and in the presence of lipopolysaccharides (LPS). Our data showed that imipramine Imipramine inhibiteds neutrophil adhesion and concomitant secretion of proteins, including matrix metalloproteinase 9 (MMP-9) and neutrophil gelatinase-associated lipocalin (NGAL), which modify the extracellular matrix and basement membranes required for cell migration. Imipramine also significantly and selectively blocked the release of the free amino acid hydroxylysine, a product of lysyl hydroxylase, an enzyme that affects the organization of the extracellular matrix by modifying collagen lysine residues. In contrast, imipramine enhanced the release of ROS by neutrophils during adhesion to fibronectin and stimulated apoptosis. The anti-inflammatory effect of imipramine may be associated with the suppression of neutrophil infiltration and their adhesion to nerve tissues by inhibiting the secretion of neutrophils, which provides these processes.

The efficiency of tritium labeling of salts of pantothenic (HO–R–COOH), hopantenic (HO–R–CH2–COOH), and 4-D-phosphopantothenic [(HO)2P(=O)–O–R–COOH] acids [R = CH2C(CH3)2CHOH–CONH(CH2)2] with thermal activation of tritium at target temperatures of 77 and 295 K was studied. The phosphate group inhibits the isotope exchange. The tritium-labeled compounds were used for studying the adsorption of pantothenic acid derivatives from aqueous solutions and in the presence of 0.9% NaCl at 297 ± 3 K onto nanodiamonds prepared by detonation synthesis (NDs). Preparation of stable ND suspensions in advance enhances the ability of NDs to adsorb the compounds studied. The parameters of the equation describing the sorption isotherms at different ionic strengths of the solution were calculated. The strength of the adsorbate retention in contact with water, 0.9% NaCl solution, 0.01 M HCl solution, and 40 g L−1 bovine serum albumin (BSA) solution was determined. The data obtained allow two mechanisms of the adsorbate retention on the ND surface to be considered: reversible adsorption due to ionic interactions and irreversible binding due to hydrophobic interactions. The strongly bound molecules undergo slow desorption in the presence of BSA. The revealed trends confirm high potential of NDs as a drug delivery platform.

This research was supported by Russian Foundation for Basic Research, project No. № 18-09-40011.

Neutrophils release branched-chain (valine, isoleucine, leucine), aromatic (tyrosine, phenylalanine) and positively charged free amino acids (arginine, ornithine, lysine, hydroxylysine, histidine) when adhere and spread onto fibronectin. In the presence of agents that impair cell spreading or adhesion (cytochalasin D, fMLP, nonadhesive substrate), neutrophils release the same amino acids, except for a sharp decrease in hydroxylysine and an increase in phenylalanine, indicating their special connection with cell adhesion. Plasma of patients with diabetes is characterized by an increased content of branched-chain and aromatic amino acids and a reduced ratio of arginine/ornithine compared to healthy human plasma. Our data showed that the secretion of neutrophils, regardless of their adhesion state, can contribute to this shift in the amino acid content. Abbreviations: BCAAs: branched-chain amino acids; Е2: 17β-estradiol; LPS: lipopolysaccharide from Salmonella enterica serovar Typhimurium; fMLP: N-formylmethionyl-leucyl-phenylalanine.

This paper reports on a complex structural analysis of the potato virus A coat protein using a set of complementary physico-chemical methods. We have demonstrated previously that this protein does not exist as individual subunits in solution and undergoes association into oligomers with subsequent transition to β‑conformation. The purpose of the present work was to study the possible mechanisms of this transformation and to search for methods that dissociate protein oligomers. To analyze the low resolution protein structure in solution, small-angle X-ray scattering was used. Stable particles representing clusters of 30 coat protein subunits were present even in an aqueous salt solution with a high ionic strength and pH (pH 10.5; 0.5 M NaCl). The particles did not dissociate in the presence of 10 mM dextran sulfates (15 and 100 kDa). Dissociation in the presence of 5.2 mM sodium dodecyl sulfate results in the formation of the subunit–detergent complexes consisting of 10–12 small particles joined together like “beads on a string”. Similar effects of sodium dodecyl sulfate were shown for serum albumins (bovine and human). Denaturation of the potato virus A coat protein molecules occurs in the presence of detergent concentrations that are seven times lower than that in albumins (5.2 and 35 mM), which confirms low stability of the potato virus A coat protein. Using spectral methods, preservation of the secondary structure and loss of the tertiary structure of the protein in its complex with sodium dodecyl sulfate have been demonstrated. Possible mechanism for protein particle formation through the interaction between unordered terminal domains and their transformation into β‑structures has been suggested.

The paper presents the results of micromagnetic and GPR surveys at No. 1 ancient quarry of Belousovsky mine. As a result of geophysical studies, we identified the local positive magnetic anomalies along the sides of the No. 1 quarry of Belousovsky mine. These anomalies are associated with the soils excavated from the quarry. According to the GPR data, the bottom topography of the ancient quarry was determined during its operation in the Bronze Age, and a three-dimensional model of the mine was created. Based on the results of the study, it is possible to estimate the number of excavated soils and the amount of ore mined.

The structure of tobacco mosaic virus (TMV) virions and stacked disk aggregates of TMV coat protein (CP) in solution was analyzed by synchrotron-based small-angle X-ray scattering (SAXS) and negative contrast transmission electron microscopy (TEM). TMV CP aggregates had a unique stability but did not have helical symmetry. According to the TEM data, they were stacked disks associated into transversely striated rod-shaped structures 300 to 800 A long. According to modeling based on the crystallographic model of the 4-layer TMV CP aggregate (PDB: 1EI7), the stacked disks represented hollow cylinders. The calculated SAXS pattern for the disks was compared to the experimental one over the entire measured range. The best correlation with the SAXS data was found for the model with the repeating central pair of discs; the SAXS curves for the stacked disks were virtually identical irrespectively of the protein isolation method. The positions of maxima on the scatter curves could be used as characteristic features of the studied samples; some of the peaks were assigned to the existing elements of the quaternary structure (periodicity of aggregate structure, virion helix pitch). Low-resolution structural data for the repolymerized TMV CP aggregates in solution under conditions similar to natural were produced for the first time. Analysis of such nano-size objects is essential for their application in biomedicine and biotechnology.

The collective memory about wars is an object of study, as well as the formation and upbringing within the educational process. The category of generation, collective memory, and psychological trauma are considered as central in the framework of the study described here. It is assumed that wars are significant for the formation of psycho-traumatic experience of a generation. Using visual methods, in which people were asked using self-report to evaluate their feelings and emotions when looking at photographs of various wars of the twentieth century, the hypothesis was tested that the role of the Second World War is the most traumatic compared to other wars due to its role, proximity in time and media effect. The conclusions are drawn about the absence of fundamental differences in the memory of World War II by all generations of Russians (N = 548 people) in all emotional and traumatic parameters, except for the parameter of feeling of pride in the results of the war.

Domestication has particular salience in archaeology, and numerous recent theoretical papers describe this process as a set of evolutionary, ongoing, social, and material relationships between humans and select other species. In contrast, analytical papers on the domestication of dogs nearly always involve a search for their origins as marked by changes in genes and morphologies. This article explores this contrast through the examination of dog remains from the Iron Age Ust’-Polui site in the western Siberian Arctic. Many of the numerous dogs represented at this site were killed and probably consumed when young, likely as part of sacrifices. Others at the site were intentionally buried. Ust’-Polui also contains abundant evidence of advanced dog sledding, including probable harness parts and portions of several complex sleds. Sacrificing and otherwise killing dogs is a domestication practice, as these activities are a form of selective breeding. Domestication of dogs at Ust’-Polui and elsewhere is more than selective breeding, as it is enabled and dependent upon specific landscapes, built things, and other species. At Ust’-Polui these at a minimum included a rich local environment, sleds and harness swivels, and freshwater fish, all of which intertwined in making the particular domestic relationships at the site possible.

A complex structural analysis of nuclear export protein NS2 (NEP) of influenza virus A has been performed using bioinformatics predictive methods and small-angle X-ray scattering data. The behavior of NEP molecules in a solution (their aggregation, oligomerization, and dissociation, depending on the buffer composition) has been investigated. It was shown that stable associates are formed even in a conventional aqueous salt solution at physiological рН value. For the first time we have managed to get NEP dimers in solution, to analyze their structure, and to compare the models obtained using the method of the molecular tectonics with the spatial protein structure predicted by us using the bioinformatics methods. The results of the study provide a new insight into the structural features of nuclear export protein NS2 (NEP) of the influenza virus A, which is very important for viral infection development.

Matrix protein M1 of Influenza virus, which forms its inner scaffold, is the most abundant amongst viral proteins. Functions of M1 protein are highly diverse, as it has to ensure both the entry of the viral genetic material into the cytoplasm of the infected cell and the assembly of new viral particles for multiplication of infection. In all these processes matrix protein interacts with lipid membranes–either viral external lipid envelope or plasma membrane of a virus-infected cell. However, molecular mechanisms of such interactions are still unclear. In this work, we used the method of fluorescent probes on the example of 1-anilinonaphthalene- 8-sulfonate to determine components of the lipid bilayer required for binding of the M1 protein to the membrane, as well as possible orientations of the protein relative to the lipid membrane. We found that for the adsorption of matrix protein M1 lipid bilayer had to contain phosphatidylserines, while neither phosphatidylethanolamine nor cholesterol promoted protein binding to the membrane. Furthermore, our data suggest that M1 protein binds negatively charged lipid bilayer by positively charged amino acids exhibiting outward anionic sites.

In our previous study, we have observed that the isolated coat proteins (CP) of the Potyvirus Potato Virus A (PVA) virions exhibit an intrinsic tendency to self-associate into various multimeric forms containing some fractions of cross-β-structure. In this report, we studied the effect of solution conditions on the structure and dissociation of isolated PVA CP using a number of complementary physicochemical methods. Analysis of the structure of PVA CP in solution was performed by limited proteolysis with MALDI-TOF mass spectrometry analysis, transmission electron microscopy, intrinsic fluorescence spectroscopy, and synchrotron small angle X-ray scattering (SAXS). Overall structural characteristics of PVA CP obtained by combination of these methods and ab initio shape reconstruction by SAXS show that PVA CP forms large multi-subunit particles. We demonstrate that a mixture of compact virus-like particles (VLP) longer than 30 nm is assembled on dialysis of isolated CP into neutral pH buffer (at low ionic strength). Under conditions of high ionic strength (0.5 M NaCl) and high pH (pH 10.5), PVA dissociates into low compactness oval-shaped particles of approximately 30 subunits (20-30 nm). The results of limited trypsinolysis of these particles (enzyme/substrate ratio 1:100, 30 min) showed the existence of non-cleavable core-fragment, consisting of 137 amino acid residues. Trypsin treatment removed only a short N-terminal fragment in the intact virions. These particles are readily reassembled into regular VLPs by changing pH back to neutral. It is possible that these particles may represent some kind of intermediate in PVA assembly in vitro and in vivo.