Brussowvirus SW13 Requires a Cell Surface-Associated Polysaccharide To Recognize Its Streptococcus thermophilus Host

Four bacteriophage-insensitive mutants (BIMs) of the dairy starter bacterium Streptococcus thermophilus UCCSt50 were isolated following challenge with Brussowvirus SW13. The BIMs displayed an altered sedimentation phenotype. Whole-genome sequencing and comparative genomic analysis of the BIMs uncovered mutations within a family 2 glycosyltransferase-encoding gene (orf06955(UCCSt50)) located within the variable region of the cell wall-associated rhamnose-glucose polymer (Rgp) biosynthesis locus (designated the rgp gene cluster here). Complementation of a representative BIM, S. thermophilus B1, with native orf06955(UCCSt50) restored phage sensitivity comparable to that of the parent strain. Detailed bioinformatic analysis of the gene product of orf06955(UCCSt50) identified it as a functional homolog of the Lactococcus lactis polysaccharide pellicle (PSP) initiator WpsA. Biochemical analysis of cell wall fractions of strains UCCSt50 and B1 determined that mutations within orf06955(UCCSt50) result in the loss of the side chain decoration from the Rgp backbone structure. Furthermore, it was demonstrated that the intact Rgp structure incorporating the side chain structure is essential for phage binding through fluorescence labeling studies. Overall, this study confirms that the rgp gene cluster of S. thermophilus encodes the biosynthetic machinery for a cell surface-associated polysaccharide that is essential for binding and subsequent infection by Brussowviruses, thus enhancing our understanding of S. thermophilus phage-host dynamics.IMPORTANCE Streptococcus thermophilus is an important starter culture bacterium in global dairy fermentation processes, where it is used for the production of various cheeses and yogurt. Bacteriophage predation of the species can result in substandard product quality and, in rare cases, complete fermentation collapse. To mitigate these risks, it is necessary to understand the phage-host interaction process, which commences with the recognition of, and adsorption to, specific host-encoded cell surface receptors by bacteriophage(s). As new groups of S. thermophilus phages are being discovered, the importance of underpinning the genomic elements that specify the surface receptor(s) is apparent. Our research identifies a single gene that is critical for the biosynthesis of a saccharidic moiety required for phage adsorption to its S. thermophilus host. The acquired knowledge provides novel insights into phage-host interactions for this economically important starter species

Материалы на основе цемента, модифицированные наноразмерными добавками

The most common and reliable material without which modern construction is indispensable is concrete. The development of construction production is pushing for new solutions to improve the quality of concrete mix and concrete. The most demanded and significant indicators of a concrete mixture are the compressive strength and mobility of the concrete mixture. Every year, the volume of research on nanomaterials as modifying components of concrete is significantly increasing, and the results indicate the prospects for their use. Nanoparticles with a large specific surface are distinguished by chemical activity, can accelerate hydration and increase strength characteristics due to nucleation and subsequent formation of C–S–H and compaction of the material microstructure. Sol of nanosilica, which can be used instead of microsilica from industrial enterprises, and carbon nanomaterial have a wide reproduction base. This paper presents studies of these types of nanomaterials and the results of their application in cement concrete. Studies have shown that the effect is also observed with the introduction of an additive containing only one type of nanoparticles. The dependence of the obtained characteristics of cement concretes on the content of these nanomaterials has been established. It has been found that the best results were obtained with an additive in which the above-mentioned nanomaterials were used together. Compressive strength of  heavy concrete samples, improved by the complex nanodispersed system, was 78.7 MPa, which exceeds the strength of the sample containing the CNT additive in a pair with a super-plasticizer by 37 %.  The paper proposes the mechanism for  action of the presented complex additive.Самым распространенным и надежным материалом, без которого не обходится современное строительство, является бетон. Развитие строительного производства подталкивает к новым решениям в улучшении качества бетонной смеси и бетона. Наиболее востребованные и значимые показатели бетонной смеси – прочность при сжатии и подвижность бетонной смеси. С каждым годом исследований наноматериалов в качестве модифицирующих компонентов бетона становится больше, а результаты указывают на перспективность их применения. Наночастицы, обладающие большой удельной поверхностью, отличаются химической активностью, могут ускорять гидратацию и повышать прочностные показатели за счет зародышеобразования и последующего формирования C–S–H, уплотнения микроструктуры материала. Широкую базу воспроизводства имеют золь нанокремнезема, который может быть использован взамен микрокремнезема с индустриальных предприятий, и углеродный наноматериал. В статье представлены исследования данных видов наноматериалов и результаты их применения в цементных бетонах. Исследования показали, что эффект наблюдается также при введении добавки, содержащей только один вид наночастиц. Установлена зависимость получаемых характеристик цементных бетонов от количества данных наноматериалов. Выявлено, что наилучшие результаты были получены с добавкой, в которой совместно использовались вышеперечисленные наноматериалы. Прочность на сжатие образцов тяжелого бетона, улучшенная комплексной нанодисперсной системой, составила 78,7 МПа, что превышает прочность образца, содержащего добавку углеродных нанотрубок в паре с суперпластификатором, на 37 %. Изучен механизм действия представленной комплексной добавки

Design of Materials for Solid Oxide Fuel Cells, Permselective Membranes, and Catalysts for Biofuel Transformation into Syngas and Hydrogen Based on Fundamental Studies of Their Real Structure, Transport Properties, and Surface Reactivity

Advances in design of materials for solid oxide fuel cells, oxygen and hydrogen separation membranes, and catalysts for biofuel conversion into syngas and hydrogen are reviewed. Application of new efficient techniques of material synthesis and characterization of their atomic-scale structure, transport properties, and reactivity allowed to develop new types of efficient cathodes and anodes for solid oxide fuel cells, asymmetric supported oxygen, and hydrogen separation membranes with high permeability and structured catalysts with nanocomposite-active components demonstrating high performance and stability to coking in steam/autothermal reforming of biofuels. © 2021 Elsevier B.V.This work was supported by the АААА-А21-121011390007-7 budget project of the Boreskov Institute of catalysis. A.A.Y. gratefully acknowledges financial support within the project CICECO — Aveiro Institute of Materials ( UIDB/50011/2020 and UIDP/50011/2020 ) financed by national funds through the FCT/MCTES and when appropriate cofinanced by FEDER under the PT2020 Partnership Agreement

Novel materials for solid oxide fuel cells cathodes and oxygen separation membranes: Fundamentals of oxygen transport and performance

In the field of modern hydrogen energy, obtaining pure hydrogen and syngas and then being able to use them for green energy production are significant problems. Developing solid oxide fuel cells (SOFC) and catalytic membranes for oxygen separation as well as materials for these devices is one of the most likely ways to solve these problems. In this work, the authors’ recent studies in this field are reviewed; the fundamentals of developing materials for SOFC cathodes and oxygen separation membranes’ permselective layers based on research of their oxygen mobility and surface reactivity are presented. Ruddlesden – Popper phases Ln2–xCaxNiO4+δ (LnCNO) and perovskite-fluorite nanocomposites PrNi0.5Co0.5O3–δ–Ce0.9Y0.1O2–δ (PNC–YDC) were studied by isotope exchange of oxygen with C18O2 and 18O2 in flow and closed reactors. For LnCNO a high oxygen mobility was shown (D* ~ 10–7 cm2/s at 700 °C), being provided by the cooperative mechanism of oxygen migration involving both regular and highly-mobile interstitial oxygen. For PNC–YDC dominated a wide fast diffusion channel via fluorite phase and interphases due to features of the redistribution of cations resulting in superior oxygen mobility (D* ~ 10–8 cm2/s at 700 °C). After optimization of composition and nanodomain structure of these materials, as cathodes of SOFC they provided a high power density, while for asymmetric supported oxygen separation membranes – a high oxygen permeability. © 2020Support of different parts of the work by the Russian Science Foundation (Project 16-13-00112) and the budget project №AAAA-A17-117041110045-9 for Boreskov Institute of Catalysis is gratefully acknowledged. The authors from the Ural Federal University are grateful to the Government of the Russian Federation (Agreement 02.A03.21.0006, Act 211). Ce 0.9 Y 0.1 O 2–δ |Ce 0.9 Gd 0.1 O 2–δ |Ni/Zr 0.84 Y 0.16 O 2–δ anodic half-cells and Ni/Al foam substrates were kindly provided by H.C. Starck, Germany and Powder Metallurgy Institute NAN Belarus, respectively. Authors would like to appreciate International Conference on Advances in Energy Systems and Environmental Engineering (ASEE19, Wroclaw, Poland, June 9-12, 2019) Organization Committee

IgTM: An algorithm to predict transmembrane domains and topology in proteins

<p>Abstract</p> <p>Background</p> <p>Due to their role of receptors or transporters, membrane proteins play a key role in many important biological functions. In our work we used Grammatical Inference (GI) to localize transmembrane segments. Our GI process is based specifically on the inference of Even Linear Languages.</p> <p>Results</p> <p>We obtained values close to 80% in both specificity and sensitivity. Six datasets have been used for the experiments, considering different encodings for the input sequences. An encoding that includes the topology changes in the sequence (from inside and outside the membrane to it and vice versa) allowed us to obtain the best results. This software is publicly available at: <url>http://www.dsic.upv.es/users/tlcc/bio/bio.html</url></p> <p>Conclusion</p> <p>We compared our results with other well-known methods, that obtain a slightly better precision. However, this work shows that it is possible to apply Grammatical Inference techniques in an effective way to bioinformatics problems.</p

Morphological, Physiological and Genetic Characteristics of Populations of the Main Plague Host Rhombomys opimus Licht., 1823 in the Central Asian Desert Natural Focus of Plague

Revealed by morphological characters, physiological status, and genetic diversity of populations of the main plague host Rhombomys opimus Licht., 1823 in Central Asia desert natural focus is described.Differences in the skull parameters of R. opimus from different populations were revealed. It’s shown that gerbils from Moyunkum are separate autonomous populations group. Samples from Moyunkum and Mangyshlak differed from other samples. In Balkhash-Alakol depression found two regional complexes: Pre-Balkhash and Dzungarian.Study results of free amino acids level in R. opimus blood serum obtained by gas-liquid chromatography of blood sera from animals captured in different zones of Central Asian focus gave statistically significant differences. To determine genetic variability in ecological and geographical isolation of R. opimus populations the DNA was genotyped.DNA samples analysis combined the studied gerbil from the desert focus into four clusters with eighteen haplotypes. R. opimus sequence analysis taking into account data from territories of Iran, Kazakhstan and China, clustered into three large clusters. First cluster combined the sequences of Kazakhstan and China samples, while great gerbil captured in Kazakhstan is located in a separate treasure. Second and third clusters include sequences of a great gerbil captured in Iran

Композиты из субмикронных сфер Y2O3 с функциональной основой наноразмерных модификаций диоксида титана: получение и характеризация

Composites anatase/Y2O3, η-TiO2/Y2O3, Degussa P25/Y2O3 and Hombifine/Y2O3 were prepared by simultaneous dispersion of Y2O3 and TiO2 powders in weakly alkaline aqueous media or dispersion of Y2O3 powders in acidic titania-containing hydrosols followed by special treatment. Initial reagents and composites were characterized by X-ray diffraction, IR spectroscopy, transmission and scanning electronic microscopy with X-ray spectral microanalysis.Впервые получены композиты анатаз/Y2O3, η-TiO2/Y2O3, Degussa P25/Y2O3 нанесением наноразмерных модификаций диоксида титана со структурами анатаза и η-модификации и Degussa P25 на субмикронные сферы Y2O3 путём совместного диспергирования порошков Y2O3 и TiO2 в слабощелочной водной среде либо диспергирования порошка Y2O3 вкислотном титансодержащем гидрозоле с последующей обработкой. Исходные вещества и композиты охарактеризованы методами рентгенографии, ИК-спектроскопии, просвечивающей и сканирующей электронной микроскопии с рентгеноспектральным микроанализом, низкотемпературной (-196°C) адсорбции азота

Belt and Road Initiative in Central Asia: Anticipating socioecological challenges from large‐scale infrastructure in a global biodiversity hotspot

Until recently, China's Belt and Road Initiative (BRI) has overlooked many of the social and environmental dimensions of its projects and actions in favor of more immediate economic and sociopolitical considerations. The main focus of investments under BRI has largely been to improve transport, telecommunication, and energy infrastructures. However, in Central Asia, biodiversity is not only foundational for the livelihoods and socioeconomic wellbeing of communities, it also shapes people's culture and identities. Furthermore, ecosystem services derived from functioning landscapes bring enormous benefit for millions of people downstream through integrated and transboundary water systems. Already under pressure from climate-induced melting of glaciers, the fate of ecologically important areas is considered in light of the potential harm arising from large-scale linear infrastructure projects and related investments under China-led BRI. Following review of some of the anticipated impacts of BRI on mountain environments and societies in the region, we highlight several emerging opportunities and then offer recommendations for development programs—aiming fundamentally to enhance the sustainability of BRI investments. Leveraging new opportunities to strengthen partner countries’ priority Sustainable Development Goals and enhancing their agency in the selection of collaborations and the standards to use in environmental impact and risk assessments are recommended

Материалы на основе цемента, модифицированные наноразмерными добавками

The most common and reliable material without which modern construction is indispensable is concrete. The deve- lopment of construction production is pushing for new solutions to improve the quality of concrete mix and concrete. The most demanded and significant indicators of a concrete mixture are the compressive strength and mobility of the concrete mixture. Every year, the volume of research on nanomaterials as modifying components of concrete is significantly increa- sing, and the results indicate the prospects for their use. Nanoparticles with a large specific surface are distinguished by chemical activity, can accelerate hydration and increase strength characteristics due to nucleation and subsequent formation of C–S–H and compaction of the material microstructure. Sol of nanosilica, which can be used instead of microsilica from industrial enterprises, and carbon nanomaterial have a wide reproduction base. This paper presents studies of these types of nanomaterials and the results of their application in cement concrete. Studies have shown that the effect is also observed with the introduction of an additive containing only one type of nanoparticles. The dependence of the obtained characteristics of cement concretes on the content of these nanomaterials has been established. It has been found that the best results were obtained with an additive in which the above-mentioned nanomaterials were used together. Compressive strength of heavy concrete samples, improved by the complex nanodispersed system, was 78.7 MPa, which exceeds the strength of the sample containing the CNT additive in a pair with a super-plasticizer by 37 %. The paper proposes the mechanism for action of the presented complex additive

Influence of the mobility of oxygen on the reactivity of La1-x Sr (x) MnO3 perovskites in methane oxidation

Radically different dependences of the activity of La1 - x Sr (x) MnO3 (x = 0-0.5) perovskites in methane oxidation on the degree of substitution of strontium for lanthanum are observed for low and high temperatures. Unsubstituted LaMnO3 exhibits the highest activity in the temperature range from 300 to 500A degrees C, while the sample with the maximum degree of substitution (La0.5Sr0.5MnO3) shows the highest activity at higher temperatures of 700-900A degrees C. In the low temperature region, the activity of La1t - x Sr (x) MnO3 is determined by the amount of weakly bound (overstoichiometric) oxygen, which is formed in cation-deficient lattices and is characterized by a thermal desorption peak with T (max) = 705A degrees C. At higher temperatures (800-900A degrees C), the strongly bound oxygen of the catalyst lattice is involved in the formation of the reaction products under both unsteady- and steady-state conditions. As a consequence, the catalytic activity in methane oxidation correlates with the apparent rate constant of oxygen diffusion in the oxide bulk