148 research outputs found

    Cellulases from Mycelial fungi <em>Penicillium verruculosum</em> as a Real Alternative to Trichoderma Enzymes in Industrial Hydrolysis of Cellulosic Biomass

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    Abstract The possibility of using the recipient strain Penicillium verruculosum B1-537 (ΔniaD) as a producer of laboratory and industrial enzymes was considered. The advantage of this strain is its ability to secrete a basic cellulase complex consisting of cellobiohydrolases, endoglucanases, and β-glucosidase, which exceeds in its hydrolytic ability the enzyme complex of Hypocrea (Trichoderma) strains. Using the expression system, the basic complex of cellulases of the recipient strain Piptochaetium verruculosum B1-537 (ΔniaD) was supplemented with new (booster) enzymes that are necessary to increase its hydrolytic activity. Enzyme preparations adapted to the processing of various types of renewable plant biomass were obtained

    Steady state of atoms in a resonant field with elliptical polarization

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    We present a complete set of analytical and invariant expressions for the steady-state density matrix of atoms in a resonant radiation field with arbitrary intensity and polarization. The field drives the closed dipole transition with arbitrary values of the angular momenta JgJ_{g} and JeJ_{e} of the ground and excited state. The steady-state density matrix is expressed in terms of spherical harmonics of a complex direction given by the field polarization vector. The generalization to the case of broad-band radiation is given. We indicate various applications of these results.Comment: revtex, 26 pages, including 3 eps figures; PRA accepted for publication;v2 three typos are fixe

    Ectothiorhodospira variabilis, sp. nov., an alkaliphilic and halophilic purple sulfur bacterium from soda lakes

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    During studies of moderately halophilic strains of Ectothiorhodospira from steppe soda lakes, we found a novel group of bacteria related to Ectothiorhodospira haloalkaliphila with salt optima at 50–80 g NaCl l”1. Phylogenetic analysis using 16S rRNA gene sequences of strains from soda lakes in Mongolia, Egypt and Siberia revealed separation of the group of new isolates from other Ectothiorhodospira species, including the closely related Ect. haloalkaliphila. DNA–DNA hybridization studies demonstrated that the new isolates form a homogeneous group at the species level, but at the same time are distinct from related species such as Ect. haloalkaliphila, Ect. vacuolata, Ect. shaposhnikovii and Ect. marina. The new isolates are considered to be strains of a novel species, for which the name Ectothiorhodospira variabilis sp. nov. is proposed, with the type strain WN22T (5VKM B-2479T 5DSM 21381T). Photosynthetic pigments of the novel species are bacteriochlorophyll a and carotenoids of the spirilloxanthin series with spirilloxanthin and derivatives thereof, together with small amounts of lycopene and rhodopin. Gas vesicles are formed by most of the strains, particularly in media containing yeast extract (0.5 g l”1) and acetate (0.5–2.0 g l”1). Sequence analysis of nifH (nitrogenase) and cbbL (RuBisCO) confirmed the assignment of the strains to the genus Ectothiorhodospira and in particular the close relationship to Ect. haloalkaliphila. The novel species Ect. variabilis is found in soda lakes separated by great geographical distances and is an alkaliphilic and halophilic bacterium that tolerates salt concentrations up to 150–200 g NaCl l”1

    Multiparametric determination of genes and their point mutations for identification of beta-lactamases

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    Breakup reaction models for two- and three-cluster projectiles

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    Breakup reactions are one of the main tools for the study of exotic nuclei, and in particular of their continuum. In order to get valuable information from measurements, a precise reaction model coupled to a fair description of the projectile is needed. We assume that the projectile initially possesses a cluster structure, which is revealed by the dissociation process. This structure is described by a few-body Hamiltonian involving effective forces between the clusters. Within this assumption, we review various reaction models. In semiclassical models, the projectile-target relative motion is described by a classical trajectory and the reaction properties are deduced by solving a time-dependent Schroedinger equation. We then describe the principle and variants of the eikonal approximation: the dynamical eikonal approximation, the standard eikonal approximation, and a corrected version avoiding Coulomb divergence. Finally, we present the continuum-discretized coupled-channel method (CDCC), in which the Schroedinger equation is solved with the projectile continuum approximated by square-integrable states. These models are first illustrated by applications to two-cluster projectiles for studies of nuclei far from stability and of reactions useful in astrophysics. Recent extensions to three-cluster projectiles, like two-neutron halo nuclei, are then presented and discussed. We end this review with some views of the future in breakup-reaction theory.Comment: Will constitute a chapter of "Clusters in Nuclei - Vol.2." to be published as a volume of "Lecture Notes in Physics" (Springer

    Infective and nonbacterial thrombotic endocarditis in patients with post-COVID-19 viral-immune myocarditis

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    The possibility of heart inflammation (both myocardial and endocardial) months after a coronavirus disease 2019 (COVID-19) has not been practically studied, especially since approaches to the treatment of myocarditis in combination with various endocarditis forms have not been developed.Aim. To study the prevalence and mechanisms of SARS-CoV-2-associated endocardial injury in patients with morphologically verified post-COVID-19 myocarditis, as well as to develop approaches to comprehensive therapy.Material and methods. The study included 18 patients with severe morphologically verified post-COVID-19 myocarditis (men, 9; 51,1±9,4 years; 35 to 66 years). Patients with prior verified myocarditis/myocardial infarction, rheumatic heart disease, and systemic immune diseases were excluded. The average time after COVID-19 was 6,5 [3.5; 10] months The diagnosis of myocarditis was confirmed by endomyocardial biopsy (including immunohistochemical examination with antibodies to CD3, CD20, CD45, CD68, and to SARS-CoV-2 antigens; polymerase chain reaction for SARS-CoV-2 RNA, DNA of cardiotropic viruses). The blood level of anticardiac antibodies was determined by indirect immunofluorescence. In addition, echocardiography, magnetic resonance imaging (n=8), cardiac multislice tomography (n=1), and coronary angiography (n=14) were performed.Results. Biopsy revealed active (n=12) and borderline (n=3) lymphocytic myocarditis, eosinophilic (n=2) and giant cell (n=1) myocarditis. In 4 patients, nonbacterial thrombotic endocarditis (NBTE) with parietal and intravascular thrombosis was diagnosed, and in one patient — infective endocarditis (IE) of the bicuspid aortic valve. Myocardial persistence of SARS-CoV-2 was detected in 72% of cases (in 3 patients — with NBTE; in 1 — with IE; in 9 — without endocarditis). Titers of anticardiac antibodies increased by 3-4 times in 94% of patients. Patients with endocarditis were characterized by larger heart chambers, lower ejection fraction (27,5±6,6 vs 36,0±13,4%), more severe pulmonary hypertension, and valvular regurgitation. Intraventricular thrombosis according to echocardiography/magnetic resonance imaging and cardiac embolism was not observed. Treatment in all patients included methylprednisolone at an average dose of 24 mg a day. In 10 patients, the result was monitored for at least 3 months as follows: the ejection fraction was 46,0±12,7% and 44,3±7,3% in patients with and without endocarditis, respectively.Conclusion. Endocarditis in patients with post-COVID-19 myocarditis was detected in 28% (1 patient — IE; 4 — NBTE). The key mechanisms of post-COVID-19 myocarditis and NBTE are long-term (up to 18 months) myocardial persistence of SARS-Cov-2 and the development of an autoimmune reaction. Endocarditis was diagnosed in more severe patients, including those with giant cell and eosinophilic myocarditis. The effectiveness of steroid therapy in combination with anticoagulants in patients with NBTE requires further study. In case of IE, steroids can also be used in the treatment of myocarditis (in combination with antibiotics and immunoglobulin)

    Involvement of yeast HSP90 isoforms in response to stress and cell death induced by acetic acid

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    Acetic acid-induced apoptosis in yeast is accompanied by an impairment of the general protein synthesis machinery, yet paradoxically also by the up-regulation of the two isoforms of the heat shock protein 90 (HSP90) chaperone family, Hsc82p and Hsp82p. Herein, we show that impairment of cap-dependent translation initiation induced by acetic acid is caused by the phosphorylation and inactivation of eIF2 alpha by Gcn2p kinase. A microarray analysis of polysome-associated mRNAs engaged in translation in acetic acid challenged cells further revealed that HSP90 mRNAs are over-represented in this polysome fraction suggesting preferential translation of HSP90 upon acetic acid treatment. The relevance of HSP90 isoform translation during programmed cell death (PCD) was unveiled using genetic and pharmacological abrogation of HSP90, which suggests opposing roles for HSP90 isoforms in cell survival and death. Hsc82p appears to promote survival and its deletion leads to necrotic cell death, while Hsp82p is a pro-death molecule involved in acetic acid-induced apoptosis. Therefore, HSP90 isoforms have distinct roles in the control of cell fate during PCD and their selective translation regulates cellular response to acetic acid stress.This work was supported by Fundacao para a Ciencia e Tecnologia and COMPETE/QREN/EU (PTDC/BIA-MIC/114116/2009), and by the Canadian Institute for Health Research (MOP 89737 to MH). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

    Microfluidic droplet platform for ultrahigh-throughput single-cell screening of biodiversity

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    © 2017, National Academy of Sciences. All rights reserved.Ultrahigh-throughput screening (uHTS) techniques can identify unique functionality from millions of variants. To mimic the natural selection mechanisms that occur by compartmentalization in vivo, we developed a technique based on single-cell encapsulation in droplets of a monodisperse microfluidic double water-in-oil-in-water emulsion (MDE). Biocompatible MDE enables in-droplet cultivation of different living species. The combination of droplet-generating machinery with FACS followed by next-generation sequencing and liquid chromatography-mass spectrometry analysis of the secretomes of encapsulated organisms yielded detailed genotype/phenotype descriptions. This platform was probed with uHTS for biocatalysts anchored to yeast with enrichment close to the theoretically calculated limit and cell-to-cell interactions. MDE-FACS allowed the identification of human butyrylcholinesterase mutants that undergo self-reactivation after inhibition by the organophosphorus agent paraoxon. The versatility of the platform allowed the identification of bacteria, including slow-growing oral microbiota species that suppress the growth of a common pathogen, Staphylococcus aureus, and predicted which genera were associated with inhibitory activity

    Different Effect of Proteasome Inhibition on Vesicular Stomatitis Virus and Poliovirus Replication

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    Proteasome activity is an important part of viral replication. In this study, we examined the effect of proteasome inhibitors on the replication of vesicular stomatitis virus (VSV) and poliovirus. We found that the proteasome inhibitors significantly suppressed VSV protein synthesis, virus accumulation, and protected infected cells from toxic effect of VSV replication. In contrast, poliovirus replication was delayed, but not diminished in the presence of the proteasome inhibitors MG132 and Bortezomib. We also found that inhibition of proteasomes stimulated stress-related processes, such as accumulation of chaperone hsp70, phosphorylation of eIF2α, and overall inhibition of translation. VSV replication was sensitive to this stress with significant decline in replication process. Poliovirus growth was less sensitive with only delay in replication. Inhibition of proteasome activity suppressed cellular and VSV protein synthesis, but did not reduce poliovirus protein synthesis. Protein kinase GCN2 supported the ability of proteasome inhibitors to attenuate general translation and to suppress VSV replication. We propose that different mechanisms of translational initiation by VSV and poliovirus determine their sensitivity to stress induced by the inhibition of proteasomes. To our knowledge, this is the first study that connects the effect of stress induced by proteasome inhibition with the efficiency of viral infection

    АССОЦИАЦИИ ПОЛИМОРФИЗМА ГЕНА ADRA2B С ФАКТОРАМИ РИСКА СЕРДЕЧНО-СОСУДИСТЫХ ЗАБОЛЕВАНИЙ В ПОПУЛЯЦИИ КОРЕННЫХ ЖИТЕЛЕЙ ГОРНОЙ ШОРИИ

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    Study objectives: examine the frequency of genotypes and alleles of I/D polymorphism of gene ADRA2B of native people living in Mountain Shoria (the Shors), as well as their association with risk factors for cardiovascular diseases.Material and methods. Overall 221 native people of Shoria were examined. The average age is51.07 ± 1.46 among males, 52.93 ± 0.96 among females (p = 0.286). Anthropometric characteristics, lipid levels of blood and I/D polymorphism of ADRA2B were studied.Results. DD genotype of the gene ADRA2B in the native population of the Shor people is associated with adiposis and high index of "waist/hip", hypertriglyceridemia. The average values of Quetelet index is higher in carriers of this genotype compared with carriers of genotype ID. Average waist indications in homozygous insertions were lower than those in homozygous deletions and heterozygotes. Patients with genotype DD have higher average levels of triglycerides, atherogenic index, cholesterol, very low density lipoproteins.Conclusion. DD allele ADRA2B genotype is responsible for adiposis and high levels of TG among native population of Shoria.Научно-исследовательский институт комплексных проблем сердечно-сосудистых заболеваний Сибирского отделения РАН, Кемерово; Новокузнецкий государственный институт усовершенствования врачей, НовокузнецкЦель исследования – изучить частоты генотипов и аллелей I/D полиморфизма гена ADRA2B в популяции коренных жителей Горной Шории (шорцев), а также их ассоциацию с факторами риска сердечно-сосудистых заболеваний.Материал и методы. Проведено клинико-эпидемиологическое исследование коренного населения труднодоступных районов Горной Шории. Сплошным методом обследован 221 человек, выборка состояла из взрослого населения (лица в возрасте 18 лет и старше). Средний возраст обследуемых составил (51,07 ± 1,46) лет у мужчин, (52,93 ± 0,96) лет у женщин (p = 0,286). Изучены антропометрические данные, показатели липидного спектра крови, I/D полиморфизм гена ADRA2B.Результаты. Генотип DD гена ADRA2B в популяции шорцев ассоциируется с ожирением и повышенным индексом «талия/бедро», гипертриглицеридемией. Средние значения индекса Кетле выше у носителей данного генотипа по сравнению с носителями генотипа ID. У гомозигот по инсерции средние показатели окружности талии оказались меньше, чем у гомозигот по делеции и у гетерозигот. Средние уровни триглицеридов, индекса атерогенности, холестерина липопротеинов очень низкой плотности были выше у лиц с генотипом DD.Заключение. В популяции шорцев маркером генетической предрасположенности к ожирению, нарушению распределения жировой ткани и гипертриглицеридемии является аллель D гена а2В-адренорецептора
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