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There is no data in the literature on the course of myocardial infarction in patients after COVID-19. Purpose to use a clinical example to present a case of postinfarction left ventricular aneurysm in a patient after undergoing COVID-19. Materials and methods: Patient T., 49 years old, was admitted to the federal state budgetary institution Federal Center of Cardiovascular Surgery of the Ministry of Health of the Russian Federation (Astrakhan) with complaints of pain in the heart with irradiation in the left shoulder and lower jaw. Considers himself ill for 7 days. It is known from anamnesis of life that the patient suffered COVID-19 two weeks ago. He has been suffering from arterial hypertension for a year. Results: A clinical example demonstrates that COVID-19 affects course of myocardial infarction: it is a risk factor for the development of post infarction aneurysm of the left ventricle in the early stages after a myocardial infarction. Myocardial infarction was accompanied by the formation of pathological Q waves, impaired conduction of the right leg of the Gis bundle a decrease in the ejection fraction of the left ventricle, acute occlusion of the right coronary artery. Postinfarction aneurysm of the left ventricle had an anterior-septal apical localization. In addition, the study of highly sensitive troponin T and N-terminal fragment of the pro-brain natriuretic peptide type B in patients with myocardial infarction complicated by postinfarction aneurysm of the left ventricle after COVID-19 is also important for determining the stages of development of pathological processes in this pathology, evaluating the effectiveness of therapy and the outcome of this pathology.

Background. The role of the VKORC1 (1639GA, rs9923231) gene polymorphism in hypersensitivity to warfarin and hypocoagulation is known. It has been proven that polymorphisms in the VKORC1 gene can lead to the progression of atherosclerosis and hypercoagulability, and, therefore, can be factors contributing to the development of acute coronary syndrome. Aim. To study the effect of polymorphic genotypes carriage of the VKORC1 gene on the clinical and laboratory parameters of patients with acute coronary syndrome. Material and methods. The pilot observational cross-sectional study involved 77 patients who were under observation in the conditions of the Federal Center for Cardiovascular Surgery in Astrakhan and the vascular center of Kirov City Hospital No. 3 (Astrakhan), from October 2020 to May 2021. Genotyping for CYP2C9, VKORC1, CYP4F2 on a PCR analyzer was performed. For statistical processing, the HardyWeinberg and Student criteria; 95% confidence interval were determined using Statistica Trial 13 and IBM SPSS Statistics 26.0. Differences were considered statistically significant at p 0.05. Results. Significant differences related to the frequency of hemodynamically significant stenosis in homozygous carriers of the GG gene for VKORC1 compared with the group of carriers of the GA genotype 3 (8.8%) versus 7 (22.5%); p=0.0058. Carriers of the GA and GG genotypes were most often diagnosed with myocardial infarction (Q- and non-Q-forming). Carriers of the AA genotype were more likely to have new or progressive angina pectoris. The level of hyperglycemia and triglyceridemia was the highest in the group of patients with the AA genotype, VKORC1 gene. Conclusion. Statistically significant differences were established in the clinical and laboratory parameters of patients with acute coronary syndrome, carriers of different genotypes of the VKORC1 gene.

A comparative study of the electronic structure of the salen ligand in the H2(Salen) molecule and the [Ni(Salen)] complex was performed using the experimental methods of XPS, UV PES, and NEXAFS spectroscopy along with DFT calculations. Significant chemical shifts of +1.0 eV (carbon), +1.9 eV (nitrogen), and −0.4 eV (oxygen) were observed in the 1s PE spectra of the salen ligand atoms when passing from a molecule to a complex, unambiguously indicating a substantial redistribution of the valence electron density between these atoms. It is proposed that the electron density transfer to the O atoms in [Ni(Salen)] occurred not only from the Ni atom, but also from the N and C atoms. This process seemed to be realized through the delocalized conjugated π-system of the phenol C 2p electronic states of the ligand molecule. The DFT calculations (total and partial DOS) for the valence band H2(Salen) and [Ni(Salen)] described well the spectral shape of the UV PE spectra of both compounds and confirmed their experimental identification. An analysis of the N and O 1s NEXAFS spectra clearly indicated that the atomic structure of the ethylenediamine and phenol fragments was retained upon passing from the free salen ligand to the nickel complex.

Methods for the preparation of two highly flexible synthetic building blocks, namely pyrrole/aminoenone and pyrrole/aminoacrylonitrile ensembles, on the basis of available starting materials such as 2-acylethynylpyrroles or pyrrole-2-carbodithioates, are summarized. The presence of several reactive centers in their molecules (pyrrole ring, enamine and carbonyl or nitrile moieties) ensures their multiple reactivity and application as versatile intermediates in the synthesis of heterocyclic ensembles such as pyrrolyl pyridines, bipyrroles, pyrrolyl-isoxazoles and condensed compounds, such as pyrrolo[3,2-a]pyrazines, pyrrolizines, which have high potential for use in medical chemistry and materials science.

Studies on the identification, properties and function of chitin in sponges (Porifera), which are recognized as the first multicellular organisms on Earth, continue to be of fundamental scientific interest. The occurrence of chitin has so far been reported in 21 marine sponge species and only in two inhabiting fresh water. In this study, we present the discovery of α-chitin in the endemic demosponge Ochridaspongia rotunda, found in Lake Ohrid, which dates from the Tertiary. The presence of chitin in this species was confirmed using special staining, a chitinase test, FTIR, Raman and NEXAFS spectroscopy, and electrospray ionization mass spectrometry (ESI-MS). In contrast to the case of marine sponges, chitin in O. rotunda has been found only within its holdfast, suggesting a role of chitin in the attachment of the sponge to the hard substratum. Isolated fibrous matter strongly resemble the shape and size of the sponge holdfast with membrane-like structure.

Marine sponges were among the first multicellular organisms on our planet and have survived to this day thanks to their unique mechanisms of chemical defense and the specific design of their skeletons, which have been optimized over millions of years of evolution to effectively inhabit the aquatic environment. In this work, we carried out studies to elucidate the nature and nanostructural organization of three-dimensional skeletal microfibers of the giant marine demosponge Ianthella basta, the body of which is a micro-reticular, durable structure that determines the ideal filtration function of this organism. For the first time, using the battery of analytical tools including three-dimensional micro—X-ray Fluorescence (3D-µXRF), X-ray diffraction (XRD), infra-red (FTIR), Raman and Near Edge X-ray Fine Structure (NEXAFS) spectroscopy, we have shown that biomineral calcite is responsible for nano-tuning the skeletal fibers of this sponge species. This is the first report on the presence of a calcitic mineral phase in representatives of verongiid sponges which belong to the class Demospongiae. Our experimental data suggest a possible role for structural amino polysaccharide chitin as a template for calcification. Our study suggests further experiments to elucidate both the origin of calcium carbonate inside the skeleton of this sponge and the mechanisms of biomineralization in the surface layers of chitin microfibers saturated with bromotyrosines, which have effective antimicrobial properties and are responsible for the chemical defense of this organism. The discovery of the calcified phase in the chitinous template of I. basta skeleton is expected to broaden the knowledge in biomineralization science where the calcium carbonate is regarded as a valuable material for applications in biomedicine, environmental science, and even in civil engineering.

The results of the research of a composite based on multi-walled carbon nanotubes (MWCNTs) decorated with CuO/Cu2O/Cu nanoparticles deposited by the cupric formate pyrolysis are discussed. The study used a complementary set of methods, including scanning and transmission electron microscopy, X-ray diffractometry, Raman, and ultrasoft X-ray spectroscopy. The investigation results show the good adhesion between the copper nanoparticles coating and the MWCNT surface through the oxygen atom bridge formation between the carbon atoms of the MWCNT outer graphene layer and the oxygen atoms of CuO and Cu2O oxides. The formation of the Cu–O–C bond between the coating layer and the outer nanotube surface is clearly confirmed by the results of the O 1s near edge X-ray absorption fine structure (NEXAFS) and X-ray photoelectron spectroscopy (XPS) of the Cu/MWCNTs nanocomposite. The XPS measurements were performed using a laboratory spectrometer with sample charge compensation, and the NEXAFS studies were carried out using the synchrotron radiation of the Russian–German dipole beamline at BESSY-II (Berlin, Germany) and the NanoPES station at the Kurchatov Center for Synchrotron Radiation and Nanotechnology (Moscow, Russia).

Siderophores produced by microorganisms to scavenge iron from the environment have been shown to contribute to virulence and/or stress resistance of some plant pathogenic bacteria. Phytopathogenic bacteria of Pectobacterium genus possess genes for the synthesis of siderophore enterobactin, which role in plant-pathogen interactions has not been elucidated. In the present study we characterized the phenotype of the mutant strain of Pba deficient for the enterobactin-biosynthetic gene entA. We showed that enterobactin may be considered as a conditionally beneficial virulence factor of Pba. The entA knockout did not reduce Pba virulence on non-primed plants, however, salicylic acid-primed plants were more resistant to ΔentA mutant than to the wild type Pba. The reduced virulence of ΔentA mutant towards the primed plants is likely explained by its compromised resistance to oxidative stress.

Pharmaceutically relevant substituted 2-(pyrazol-5-yl)-4,5,6,7-tetrahydropyrrolo [3,2-c]pyridines have been assembled in good to excellent yields via the reaction of 2,2,6,6-tetramethylpiperidin-4-one oxime with acetylene, cross-coupling of the resulting 4,4,6,6-tetramethyl-4,5,6,7 tetrahydropyrrolo[3,2-c]pyridines with aroylbromoacetylenes, and reaction of the formed 2-(aroylethynyl)-4,4,6,6-tetramethyl-4,5,6,7-tetrahydropyrrolo[3,2-c]pyridines with hydrazine.

Soft rot Pectobacteriaceae (SRP) are ubiquitous on earth as there are records of findings from all continents where host plants are grown. This chapter describes information on soft rot diseases on these continents. For some countries, detailed information is provided by local experts on the SRP present, their economic damage, and the management strategies applied for their control. The focus of the chapter is mainly on SRP as causative agents of potato blackleg, although in specific cases details are provided on SRP in other host plants. In Europe, the SRP cause important economic losses mainly on potato, with most species described in the literature being found. In Latin America significant losses are also reported due to potato diseases caused by various Dickeya and Pectobacterium species, while in Australia and Oceania, recent outbreaks of D. dianthicola in potato have resulted in high economic losses. In Asia, however, SRP cause economic losses mainly in vegetable crops other than potato, while in North America SRP cause diseases on a wide range of crops (including potato and ornamental plants) in both field and storage. In Africa SRP are only known to occur in 17 of the 54 African countries but where it is known, potato is the most affected crop.

Exploitation of natural forests forms expanding frontiers. Simultaneously, protected area frontiers aim at maintaining functional habitat networks. To assess net effects of these frontiers, we examined 16 case study areas on five continents. We (1) mapped protected area instruments, (2) assessed their effectiveness, (3) mapped policy implementation tools, and (4) effects on protected areas originating from their surroundings. Results are given as follows: (1) conservation instruments covered 3–77%, (2) effectiveness of habitat networks depended on representativeness, habitat quality, functional connectivity, resource extraction in protected areas, time for landscape restoration, “paper parks”, “fortress conservation”, and data access, (3) regulatory policy instruments dominated over economic and informational, (4) negative matrix effects dominated over positive ones (protective forests, buffer zones, inaccessibility), which were restricted to former USSR and Costa Rica. Despite evidence-based knowledge about conservation targets, the importance of spatial segregation of conservation and use, and traditional knowledge, the trajectories for biodiversity conservation were generally negative., Ambio, 50 (12), ISSN:0044-7447, ISSN:1654-7209

There are “molecular switchers” that transform peaceful coexistence of plants with phytopathogenic pectobacteria to symptomatic infection. These switchers seem to be perspective “targets” for plant protection approaches.

Snow mold is a severe plant disease caused by psychrophilic or psychrotolerant fungi, of which Microdochium species are the most harmful. A clear understanding of Microdochium biology has many gaps, the pathocomplex and its dynamic are poorly characterized, virulence factors are unknown, genome sequences are not available, and the criteria of plant snow mold resistance are not elucidated. Our study aimed to identify comprehensive characteristics of a local community of snow mold-causing Microdochium species colonizing a particular crop culture. By using the next-generation sequencing (NGS) technique, we characterized fungal and bacterial communities of pink snow mold-affected winter rye (Secale cereale) plants within a given geographical location shortly after snowmelt. Twenty-one strains of M. nivale were isolated, classified on the basis of internal transcribed spacer 2 (ITS2) region, and characterized by morphology, synthesis of extracellular enzymes, and virulence. Several types of extracellular enzymatic activities, the level of which had no correlations with the degree of virulence, were revealed for Microdochium species for the first time. Our study shows that genetically and phenotypically diverse M. nivale strains simultaneously colonize winter rye plants within a common area, and each strain is likely to utilize its own, unique strategy to cause the disease using &ldquo, a personal&rdquo, pattern of extracellular enzymes.

Soft rot caused by Pectobacterium species is a devastating plant disease poorly characterized in terms of host plant responses. In this study, changes in the transcriptome of tobacco plants after infection with Pectobacterium atrosepticum (Pba) were analyzed using RNA-Seq. To draw a comprehensive and nontrivially itemized picture of physiological events in Pba-infected plants and to reveal novel potential molecular &ldquo, players&rdquo, in plant&ndash, Pba interactions, an original functional gene classification was performed. The classifications present in various databases were merged, enriched by &ldquo, missed&rdquo, genes, and divided into subcategories. Particular changes in plant cell wall-related processes, perturbations in hormonal and other regulatory systems, and alterations in primary, secondary, and redox metabolism were elucidated in terms of gene expression. Special attention was paid to the prediction of transcription factors (TFs) involved in the disease&rsquo, s development. Herewith, gene expression was analyzed within the predicted TF regulons assembled at the whole-genome level based on the presence of particular cis-regulatory elements (CREs) in gene promoters. Several TFs, whose regulons were enriched by differentially expressed genes, were considered to be potential master regulators of Pba-induced plant responses. Differential regulation of genes belonging to a particular multigene family and encoding cognate proteins was explained by the presence/absence of the particular CRE in gene promoters.

Currently, X-ray photoelectron spectroscopy (XPS) is widely used to characterize the nanostructured material surface. The ability to determine the atom distribution and chemical state with depth without the sample destruction is important for studying the internal structure of the coating layer several nanometers thick, and makes XPS the preferable tool for the non-destructive testing of nanostructured systems. In this work, ultra-soft X-ray spectroscopy methods are used to study hidden layers and interfaces of pyrolytic tungsten carbide nanoscale coatings on the multi-walled carbon nanotube (MWCNT) surfaces. XPS measurements were performed using laboratory spectrometers with sample charge compensation, and Near Edge X-ray Absorption Fine Structure (NEXAFS) studies using the Russian&ndash, German dipole beamline (RGBL) synchrotron radiation at BESSY-II. The studied samples were tested by scanning and transmission electron microscopy, X-ray diffractometry, Raman scattering and NEXAFS spectroscopy. It was shown that the interface between MWCNT and the pyrolytic coating of tungsten carbide has a three-layer structure: (i) an interface layer consisting of the outer graphene layer carbon atoms, forming bonds with oxygen atoms from the oxides adsorbed on the MWCNT surface, and tungsten atoms from the coating layer, (ii) a non-stoichiometric tungsten carbide WC1-x nanoscale particles layer, (iii) a 3.3 nm thick non-stoichiometric tungsten oxide WO3-x layer on the WC1-x/MWCNT nanocomposite outer surface, formed in air. The tungsten carbide nanosized particle&rsquo, s adhesion to the nanotube outer surface is ensured by the formation of a chemical bond between the carbon atoms from the MWCNT upper layer and the tungsten atoms from the coating layer.

Проведены исследования нанокомпозитов, полученных путем осаждения методом MOCVD с использованием хроморганической жидкости «Бархос» слоев разной толщины пиролитического хрома на внешнюю поверхность многостенных углеродных нанотрубок (МУНТ). Данные покрытия из пиролитического Cr имеют высокую микротвердость, термостойкость, гидрофобность и химическую стойкость по отношению к соляной и серной кислотам и расплаву щелочей.Уникальные физические свойства хромовых покрытий, а также химическая стойкость в широком диапазоне температур и большая внешняя поверхность МУНТ открывают широкие перспективы возможных приложений исследуемых нанокомпозитов. Важной проблемой в этом случае является выяснение механизмов адгезии хрома на химически инертную поверхность МУНТ.Перспективным методом изучения интерфейса поверхность МУНТ – покрывающий слой является ультрамягкая рентгеновская спектроскопия в области NEXAFS 1s – порога ионизации углерода. Однако такие исследования для соединений хрома практически отсутствуют в литературе по причине наложения структуры NEXAFS Cr2p-спектров поглощения на область NEXAFS C1s – порога ионизации. В настоящей работе исследования нанокомпозитов были проведены методом полного выхода электронов с использованием оригинальной методики подавления и измерениявклада кратных порядков в области C1s – края поглощения. Проведенные методами NEXAFS и XPS-спектроскопии исследования нанокомпозита (пиролитический Cr) / МУНТ показали: (i) в спектре композита сохраняются особенности, характерные для чистой МУНТ; (ii) отсутствиесущественной деструкции внешних слоев МУНТ; (iii) интерфейс между МУНТ и покрытием пиролитического хрома представляет собой многослойную структуру. Эта структура включает внешнюю поверхность МУНТ, атомы которой образуют С–О и С–Cr связи с покрытием пиролитического хрома, монослой карбида хрома и покрывающий слой оксида хрома (Cr2O3). Для исследованных образцов определены эффективные толщины покрывающих слоев оксидаи карбида хрома 1.5 и 0.3 нм соответственно. ЛИТЕРАТУРА Ob’edkov A. M., Kaverin B. S., Gusev S. A., Ezerskii A. B., Semenov N. M., Zaytsev A. A., Egorov V. A., Domrachev G. A. MOCVD modifi cation of the surface of multiwalled carbon nanotubes to impart to them necessary physicochemical properties. Journal of Surface Investigation. 2009; 3(4): 554–558. DOI: https://doi.org/10.1134/S1027451009040120 Кириллов А. И., Объедков А. М., Егоров В. А., Домрачев Г. А., Каверин Б. С., Семенов Н. М., Лопатина Т. И., Гусев С. А., Мансфельд А. Д. Создание с помощью MOCVD-технологии наноструктурированных композиционных материалов на основе многостенных углеродных нанотрубок. Нанотехника. 2011; 1(25): 72–78. Sivkov V. N., Ob’edkov A. M., Petrova O. V., Nekipelov S. V., Kremlev K.V ., Kaverin B. S., Semenov N. M., Gusev S. A. X-ray and synchrotron investigations of heterogeneous systems based on multiwalled carbon nanotubes. Physics of the Solid State. 2015;57(1): 197–204. DOI: https://doi.org/10.1134/S1063783415010291 Petrova O. V., Nekipelov S. V., Mingaleva A. E., Sivkov V. N., Obiedkov A. M., Kaverin B. S., Kremlev K. V., Ketkov S. Yu., Gusev S. A., Vyalikh D. V., Molodtsov S. L. Study of composite MWCNT/pyrolytic Cr interface by NEXAFS spectroscopy. Journal of Physics: Conference Series. 2016;741(1): 012038. DOI: https://doi.org/10.1088/1742-6596/741/1/012038 Fedoseenko S. I., Iossifov I. F., Gorovikov S. A., Schmidt J., Follath R., Molodtsov S. L., Adamchuk V. K., Kaindl G. Development and present status of the Russian-German soft X-ray beamline at BESSY II. Nucl. Instr. and Meth. A. 2001;470: 84-88. DOI: https://doi.org/10.1016/S0168-9002(01)01032-4 Kummer K., Sivkov V. N., Vyalikh D. V., Maslyuk V. V., Bluher A., Nekipelov S. V., Bredow T., Mertig I., Mertig M., Molodtsov S. L. Oscillator strength of the peptide bond p*-resonances at all relevant x-ray absorption edges. Physical Review B. 2009;80: 155433–155438. DOI: https://doi.org/10.1103/PhysRevB.80.155433 Jeong H.-K., Noh H.-J., Kim J.-Y., Jin M.H., Park C. Y., and Lee Y. H. X-ray absorption spectroscopy of graphite oxide. Europhysics Letters. 2008;82: 67004-1–5. DOI: https://doi.org/10.1209/0295-5075/82/67004 Madix R. J., Solomon J. L., and Stцhr J. The orientation of the carbonate anion on Ag(110). Surf. Sci. 1988;197: L253–L259. DOI: https://doi.org/10.1016/0039-6028(88)90624-3 Chen J. G. NEXAFS investigations of transition metal oxides, nitrides, carbides, sulfi des and otherinterstitial compounds. Surface Science Report. 1997;30: 1–152. DOI: https://doi.org/10.1016/S0167-5729(97)00011-3 Ruihua Cheng B. Xu., Borca C. N., Sokolov A., Yang C.-S., Yuan L., Liou S.-H., Doudin B., Dowben P. A. Characterization of the native Cr2O3 oxide surface of CrO2. Appl. Phys. Letters. 2001;79: 3122–3124. DOI: https://doi.org/10.1063/1.1416474 NIST Standard Reference Database 71. NIST Electron Inelastic-Mean-Free-Path Database: Version1.2. Режим доступа: www.nist.gov/srd/nist-standardreference-database-71 Teghil R., Santagata A., De Bonis A., Galasso A., Villani P. Chromium carbide thin fi lms deposited by ultra-short pulse laser deposition. Applied Surface Science. 2009; 255: 7729–7733. DOI: https://doi.org/10.1016/j.apsusc.2009.04.151 Zhao D., Jiang X., Wang Y., Duan W., Wang L. Microstructure evolution, wear and corrosion resistance of Cr-C nanocomposite coatings in seawater. Applied Surface Science. 2018;457: 914–924. DOI: https://doi.org/10.1016/j.apsusc.2018.06.248

The paper is devoted to the structure and properties of the composite material based on multi-walled carbon nanotubes (MWCNTs) covered with pyrolytic iron and chromium. Fe/MWCNTs and Cr/MWCNTs nanocomposites have been prepared by the metal organic chemical vapor deposition (MOCVD) growth technique using iron pentacarbonyl and bis(arene)chromium compounds, respectively. Composites structures and morphologies preliminary study were performed using X-ray diffraction, scanning and transmission electron microscopy and Raman scattering. The atomic and chemical composition of the MWCNTs&rsquo, surface, Fe-coating and Cr-coating and interface&mdash, (MWCNTs surface)/(metal coating) were studied by total electron yield method in the region of near-edge X-ray absorption fine structure (NEXAFS) C1s, Fe2p and Cr2p absorption edges using synchrotron radiation of the Russian-German dipole beamline (RGBL) at BESSY-II and the X-ray photoelectron spectroscopy (XPS) method using the ESCALAB 250 Xi spectrometer and charge compensation system. The absorption cross sections in the NEXAFS C1s edge of the nanocomposites and MWCNTs were measured using the developed approach of suppressing and estimating the contributions of the non-monochromatic background and multiple reflection orders radiation from the diffraction grating. The efficiency of the method was demonstrated by the example of the Cr/MWCNT nanocomposite, since its Cr2p NEXAFS spectra contain additional C1s NEXAFS in the second diffraction order. The study has shown that the MWCNTs&rsquo, top layers in composite have no significant destruction, the MWCNTs&rsquo, metal coatings are continuous and consist of Fe3O4 and Cr2O3. It is shown that the interface between the MWCNTs and pyrolytic Fe and Cr coatings has a multilayer structure: a layer in which carbon atoms along with epoxy &ndash, C&ndash, O&ndash, bonds form bonds with oxygen and metal atoms from the coating layer is formed on the outer surface of the MWCNT, a monolayer of metal carbide above it and an oxide layer on top. The iron oxide and chromium oxide adhesion is provided by single, double and epoxy chemical binding formation between carbon atoms of the MWCNT top layer and the oxygen atoms of the coating, as well as the formation of bonds with metal atoms.

The article represents a retrospective of nature conservation in the Murmansk Region. It is devoted to the period since the first State Nature Reserves to the present day. Today, the network of Protected Areas (PA) in the Murmansk Region consists of three nature state Reserves, one National Park, two nat-ural parks, 12 protected areas “Zakaznik”, 55 nature monuments and the protected area of the Polar-Alpine Botanical Garden-Institute. The total area of the PA is 1,947,799.4 hectares or 13.4% of the Mur-mansk Region. An effectiveness of the PA was assessed due to the correspondence of the protection regimes and the threats. The authors concluded that effective environmental protection could be realized only in small part of PA, mainly in nature state reserves and national park, whose total area is only 4.2% of the Murmansk Region. At the present level of efficiency, even if it will be possible to achieve a share of Pas equal to 16.4% of the region’s area, it is hardly possible to guarantee the proper level of biodiversity conservation and the stability of the ecosystem of the region.

In the present study, we have monitored the process of systemic plant colonization by the plant pathogenic bacterium Pectobacterium atrosepticum (Pba) using RNA-Seq analysis in order to compare bacterial traits under in planta and in vitro conditions and to reveal potential players that participate in switching from stealth to brute force strategy of the pathogen. Two stages of tobacco plant colonization have been assayed: i) the initial one associated with visually symptomless spread of bacteria throughout the host body via primary xylem vessels where bacterial emboli were formed (stealth strategy), and ii) the advanced stage coupled with an extensive colonization of core parenchyma and manifestation of soft rot symptoms (brute force strategy). Plant-inducible genes in Pba and potential players switching the pathogen’s behavior were revealed. Genes from the cfa locus responsible for the production of coronafacic acid displayed the strongest induction in the asymptomatic zone relative to the symptomatic one and were shown experimentally to act as the true strategy “switchers” of Pba behavior in planta. Surprisingly, cfa genes appeared to be unnecessary for establishment of the asymptomatic stage of plant colonization but were required for the transition to soft-rot-associated symptomatic stage coupled with over-induction of jasmonate-mediated pathway in the plant.

Pyrrolo[2,3-f]quinoxalines are synthesized by heating 1,2,5-oxadiazolo[3,4-g]indoles with ethanolamine in the presence of p-toluenesulfonic acid.

The phytopathogenic bacterium Pectobacterium atrosepticum (Pba), one of the members of the soft rot Pectobacteriaceae, forms biofilm-like structures known as bacterial emboli when colonizing the primary xylem vessels of the host plants. The initial extracellular matrix of the bacterial emboli is composed of the host plant’s pectic polysaccharides, which are gradually substituted by the Pba-produced exopolysaccharides (Pba EPS) as the bacterial emboli “mature”. No information about the properties of Pba EPS and their possible roles in Pba-plant interactions has so far been obtained. We have shown that Pba EPS possess physical properties that can promote the maintenance of the structural integrity of bacterial emboli. These polymers increase the viscosity of liquids and form large supramolecular aggregates. The formation of Pba EPS aggregates is provided (at least partly) by the acetyl groups of the Pba EPS molecules. Besides, Pba EPS scavenge reactive oxygen species (ROS), the accumulation of which is known to be associated with the formation of bacterial emboli. In addition, Pba EPS act as suppressors of the quantitative immunity of plants, repressing PAMP-induced reactions; this property is partly lost in the deacetylated form of Pba EPS. Overall, our study shows that Pba EPS play structural, protective, and immunosuppressive roles during Pba–plant interactions and thus should be considered as virulence factors of these bacteria.

The Green Belt of Fennoscandia (GBF) is the Russian-Finnish-Norwegian border region with forest areas and mire massifs almost unaffected by human activity. In the early 1990s, the concept of the Green Belt of Fennoscandia was put forward as a result of joint work of researchers and experts in Fennoscandia and discussion of sustainable development principles for border regions. Its main aim was to have public interests united in the fields of economic development and nature conservation. The cores of the GBF are protected areas (PAs), of federal and regional status, and ecologically connected with the Pan-European Ecological Network (Natura 2000) as well as with Norwegian PAs.

Our study is the first to consider the changes in the entire set of matrix plant cell wall (PCW) polysaccharides in the course of a plant infectious disease. We compared the molecular weight distribution, monosaccharide content, and the epitope distribution of pectic compounds and cross-linking glycans in non-infected potato plants and plants infected with Pectobacterium atrosepticum at the initial and advanced stages of plant colonization by the pathogen. To predict the gene products involved in the modification of the PCW polysaccharide skeleton during the infection, the expression profiles of potato and P. atrosepticum PCW-related genes were analyzed by RNA-Seq along with phylogenetic analysis. The assemblage of P. atrosepticum biofilm-like structures—the bacterial emboli—and the accumulation of specific fragments of pectic compounds that prime the formation of these structures were demonstrated within potato plants (a natural host of P. atrosepticum). Collenchyma was shown to be the most “vulnerable” tissue to P. atrosepticum among the potato stem tissues. The infection caused by the representative of the Soft Rot Pectobacteriaceae was shown to affect not only pectic compounds but also cross-linking glycans, the content of the latter was increased in the infected plants compared to the non-infected ones.

The photoluminescence from n-hexane solutions of the dyes obtained by the introduction of amino groups into the meta position of the phenyl rings of 3,5-diphenyl-8-CF3-BODIPY was found to be strongly quenched by some aromatic molecules (benzene and toluene). On the contrary, the introduction of an amino group into the para position does not lead to significant quenching. The quenching of photoluminescence from the meta derivatives obeys the mixed static + dynamic mechanism. Temperature-dependent time-resolved fluorescence measurements were performed to determine the Stern—Volmer constants of the static and dynamic components of quenching. It follows from these data that the binding energy between luminophore and toluene molecules is about 5.0 kcal/mol in the ground state and larger than 3.4 kcal/mol in the excited state. Complexation with toluene facilitates the intramolecular charge transfer in the BODIPY derivatives with the meta position of the amino groups, resulting in photoluminescence quenching.

In the present study, we attempted to elucidate if the harmful phytopathogenic bacteria of Pectobacterium genus (P. atrosepticum) possess the enzymes for oxidation of phenolic compounds. Polyphenol oxidase (laccase) activity was revealed in P. atrosepticum cell lysates. Using bioinformatic analysis, an ORF encoding a putative copper-containing polyphenol oxidase of 241 amino acids with a predicted molecular mass of 25.9 kDa was found. This protein (named Pal1) shares significant level of identity with laccases of a new type described for several bacterial species. Cloning and expression of the pal1 gene and the analysis of corresponding recombinant protein confirmed that Pal1 possessed laccase activity. The recombinant Pal1 protein was characterized in terms of substrate specificity, kinetic parameters, pH and temperature optimum, sensitivity to inhibitors and metal content. Pal1 demonstrated alkali- and thermo-tolerance. The kinetic parameters Km and kcat for 2,6-dimethoxyphenol were 0.353 ± 0.062 mM and 98.79 ± 4.9 s-1 , respectively. The protein displayed high tolerance to sodium azide, sodium fluoride, NaCl, SDS and cinnamic acid. The transcript level of the pal1 gene in P. atrosepticum was shown to be induced by plant-derived phenolic compound (ferulic acid) and copper sulfate.