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Superconducting hybrid structures based on single nanowires are a new type of nanoscale devices with peculiar transport characteristics. Control over the nanowire structure is essential for understanding hybrid electronic phenomena arising in such complex systems. In this work, we report a technique for the fabrication of cobalt nanowires by template-assisted electrodeposition usingiRcompensation, which allows revealing the fundamental dependence of the preferred direction of nanowire growth on the deposition potential. Long coarse-grained cobalt nanowires with a diameter of 70 nm have been implemented into Nb/Co/Nb hybrid structures. We demonstrate that using electrode fabrication techniques that do not contaminate the surface of the nanowire leads to a high quality of devices with low-resistance interfaces. Low-temperature resistivity of 4.94 ± 0.83µΩ cm and other transport characteristics of Co nanowires are reported. The absence of long-range superconducting proximity effect for Nb/Co/Nb systems with different nanowire length is discussed.
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Understanding the fatigue behaviour of hybrid fibre-reinforced plastics is desirable for exploiting their features in safe, durable and reliable industrial components. The fatigue performance of hybrid composites has not been extensively investigated yet. The paper presents an overview of the available knowledge on the fatigue of hybrid fibre-reinforced plastics, and, more specifically, reports the fatigue behaviour of a quasi-isotropic pseudo-ductile all-carbon fibre interlayer hybrid composite by experimental measurements and observations, with emphasis on the damage development. The fatigue conditions are tension-tension stress- and strain-controlled cyclic loading. The results include fatigue life for different maximum stress and strain levels, stiffness evolution and damage observations by X-ray micro-computed tomography. The studied hybrid all-carbon fibre quasi-isotropic composite exhibits pseudo-ductility in quasi-static testing. For stress-controlled fatigue, the fatigue load over the limit of elastic response is not sustained. Contrary to that, the composite retains its load-carrying ability in the pseudo-ductile regime for a strain-controlled regime, albeit with lowered stiffness. This article is part of the theme issue 'Ageing and durability of composite materials'.
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Nano-sized archaeota, with their small genomes and limited metabolic capabilities, are known to associate with other microbes, thereby compensating for their own auxotrophies. These diminutive and yet ubiquitous organisms thrive in hypersaline habitats that they share with haloarchaea. Here, we reveal the genetic and physiological nature of a nanohaloarchaeon-haloarchaeon association, with both microbes obtained from a solar saltern and reproducibly cultivated together in vitro. The nanohaloarchaeon Candidatus Nanohalobium constans LC1Nh is an aerotolerant, sugar-fermenting anaerobe, lacking key anabolic machinery and respiratory complexes. The nanohaloarchaeon cells are found physically connected to the chitinolytic haloarchaeon Halomicrobium sp. LC1Hm. Our experiments revealed that this haloarchaeon can hydrolyze chitin outside the cell (to produce the monosaccharide N-acetylglucosamine), using this beta-glucan to obtain carbon and energy for growth. However, LC1Hm could not metabolize either glycogen or starch (both alpha-glucans) or other polysaccharides tested. Remarkably, the nanohaloarchaeon's ability to hydrolyze glycogen and starch to glucose enabled growth of Halomicrobium sp. LC1Hm in the absence of a chitin. These findings indicated that the nanohaloarchaeon-haloarchaeon association is both mutualistic and symbiotic; in this case, each microbe relies on its partner's ability to degrade different polysaccharides. This suggests, in turn, that other nano-sized archaeota may also be beneficial for their hosts. Given that availability of carbon substrates can vary both spatially and temporarily, the susceptibility of Halomicrobium to colonization by Ca Nanohalobium can be interpreted as a strategy to maximize the long-term fitness of the host.
Assuntos
Halobacteriaceae/fisiologia , Nanoarchaeota/fisiologia , Polissacarídeos/metabolismo , Simbiose/fisiologia , Proteínas Arqueais/genética , Proteínas Arqueais/metabolismo , Técnicas de Cocultura , Regulação da Expressão Gênica em Archaea , Genoma Arqueal , Genômica , FilogeniaRESUMO
Solanum tuberosum L. (common potato) is one of the most important crops produced almost all over the world. Genomic sequences of potato opens the way for studying the molecular variations related to diversification. We performed a reconstruction of genomic sequences for 15 tetraploid potato cultivars grown in Russia using short reads. Protein-coding genes were identified; conserved and variable parts of pan-genome and the repertoire of the NBS-LRR genes were characterized. For comparison, we used additional genomic sequences for twelve South American potato accessions, performed analysis of genetic diversity, and identified the copy number variations (CNVs) in two these groups of potato. Genomes of Russian potato cultivars were more homogeneous by CNV characteristics and have smaller maximum deletion size in comparison with South American ones. Genes with different CNV occurrences in two these groups of potato accessions were identified. We revealed genes of immune/abiotic stress response, transport and five genes related to tuberization and photoperiod control among them. Four genes related to tuberization and photoperiod were investigated in potatoes previously (phytochrome A among them). A novel gene, homologous to the poly(ADP-ribose) glycohydrolase (PARG) of Arabidopsis, was identified that may be involved in circadian rhythm control and contribute to the acclimatization processes of Russian potato cultivars.
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Solanum tuberosum , Solanum tuberosum/genética , Variações do Número de Cópias de DNA , Genoma de Planta , Genômica , TetraploidiaRESUMO
OBJECTIVE: The aim: To analyze the results of inflammatory and immunological parameters of the oral cavity after cystectomy with different methods of connecting the edges of the operated area. PATIENTS AND METHODS: Materials and methods: The research was conducted in 87 patients who sought surgical treatment of odontogenic cysts of the jaws. Patients were divided into groups depending on the method of wound closure after surgery. We analyzed the results of laboratory tests (leukocytes, ESR, IL-1ß, IL-6, TNF-α, IL-8, NO synthase, MMP-9). RESULTS: Results: The analysis of the effectiveness of using different methods of approximation of the oral mucosa wound on inflammatory and immunological pa¬rameters showed that when using welding of the edges of the operated area using the EKVZ-300 "Patonmed" apparatus, we get positive results of laboratory indicators of inflammatory markers faster (leukocyte counts are normal on day 30, ESR, IL-1ß - on the 14th day, TNF-α - on the 7th day, IL-6, IL-8, NO synthase, MMP-9 - on the 30th day), that is, healing in such patients is faster than in patients with wound closure with classic suture material or laser. CONCLUSION: Conclusions: When comparing the methods of approximation of postoperative oral mucosa wounds by different methods, based on the results of these inflammatory and immunological parameters, the best results were obtained when using electric welding of tissues. Further research and use of the proposed method will facilitate and shorten the rehabilitation period of patients after surgery.
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Metaloproteinase 9 da Matriz , Fator de Necrose Tumoral alfa , Humanos , Interleucina-6 , Cistectomia , Interleucina-8 , Mucosa Bucal/cirurgiaRESUMO
New antioxidants are commonly evaluated via two main approaches, i.e., the ability to donate an electron and the ability to intercept free radicals. We compared these approaches by evaluating the properties of 11 compounds containing both antioxidant moieties (mono- and polyphenols) and auxiliary pharmacophores (pyrrolidone and caprolactam). Several common antioxidants, such as butylated hydroxytoluene (BHT), 2,3,5-trimethylphenol (TMP), quercetin, and dihydroquercetin, were added for comparison. The antioxidant properties of these compounds were determined by their rates of reaction with 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical and their oxidation potentials from cyclic voltammetry. Although these methods test different chemical properties, their results correlate reasonably well. However, several exceptions exist where the two methods give opposite predictions! One of them is the different behavior of mono- and polyphenols: polyphenols can react with DPPH more than an order of magnitude faster than monophenols of a similar oxidation potential. The second exception stems from the size of a "bystander" lactam ring at the benzylic position. Although the phenols with a seven-membered lactam ring are harder to oxidize, the sterically nonhindered compounds react with DPPH about 2× faster than the analogous five-membered lactams. The limitations of computational methods, especially those based on a single parameter, are also evaluated and discussed.
Assuntos
Antioxidantes , Caprolactama , Antioxidantes/química , Antioxidantes/farmacologia , Compostos de Bifenilo/química , Hidroxitolueno Butilado/química , Fenóis/química , Picratos/química , Polifenóis , PirrolidinonasRESUMO
Type II toxin-antitoxins systems are widespread in prokaryotic genomes. Typically, they comprise two proteins, a toxin, and an antitoxin, encoded by adjacent genes and forming a complex in which the enzymatic activity of the toxin is inhibited. Under stress conditions, the antitoxin is degraded liberating the active toxin. Though thousands of various toxin-antitoxins pairs have been predicted bioinformatically, only a handful has been thoroughly characterized. Here, we describe the AtaT2 toxin from a toxin-antitoxin system from Escherichia coli O157:H7. We show that AtaT2 is the first GNAT (Gcn5-related N-acetyltransferase) toxin that specifically targets charged glycyl tRNA. In vivo, the AtaT2 activity induces ribosome stalling at all four glycyl codons but does not evoke a stringent response. In vitro, AtaT2 acetylates the aminoacyl moiety of isoaccepting glycyl tRNAs, thus precluding their participation in translation. Our study broadens the known target specificity of GNAT toxins beyond the earlier described isoleucine and formyl methionine tRNAs, and suggest that various GNAT toxins may have evolved to specificaly target other if not all individual aminoacyl tRNAs.
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Acetiltransferases/genética , Escherichia coli O157/genética , Glicina-tRNA Ligase/genética , Biossíntese de Proteínas/genética , Antitoxinas/genética , Toxinas Bacterianas/genética , Escherichia coli O157/patogenicidade , Sistemas Toxina-Antitoxina/genéticaRESUMO
The Calvin-Benson-Bassham (CBB) cycle assimilates CO2 for the primary production of organic matter in all plants and algae, as well as in some autotrophic bacteria. The key enzyme of the CBB cycle, ribulose-bisphosphate carboxylase/oxygenase (RubisCO), is a main determinant of de novo organic matter production on Earth. Of the three carboxylating forms of RubisCO, forms I and II participate in autotrophy, and form III so far has been associated only with nucleotide and nucleoside metabolism. Here, we report that form III RubisCO functions in the CBB cycle in the thermophilic chemolithoautotrophic bacterium Thermodesulfobium acidiphilum, a phylum-level lineage representative. We further show that autotrophic CO2 fixation in T. acidiphilum is accomplished via the transaldolase variant of the CBB cycle, which has not been previously demonstrated experimentally and has been considered unlikely to occur. Thus, this work reveals a distinct form of the key pathway of CO2 fixation.
Assuntos
Processos Autotróficos , Proteínas de Bactérias/metabolismo , Firmicutes/enzimologia , Fotossíntese , Ribulose-Bifosfato Carboxilase/metabolismo , Dióxido de Carbono/metabolismo , Sequestro de Carbono , Redes e Vias MetabólicasRESUMO
Diseases caused by the Gram-positive bacterium Curtobacteriumflaccumfaciens pv. flaccumfaciens (Cff) inflict substantial economic losses in soybean cultivation. Use of specific bacterial viruses (bacteriophages) for treatment of seeds and plants to prevent the development of bacterial infections is a promising approach for bioprotection in agriculture. Phage control has been successfully tested for a number of staple crops. However, this approach has never been applied to treat bacterial diseases of legumes caused by Cff, and no specific bacteriophages have been known to date. This paper presents detailed characteristics of the first lytic bacteriophage infecting this pathogen. Phage Ayka, related to φ29-like (Salasmaviridae) viruses, but representing a new subfamily, was shown to control the development of bacterial wilt and tan spot in vitro and in greenhouse plants.
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Actinomycetales , Infecções Bacterianas , Bacteriófagos , Fabaceae , Actinobacteria , Bactérias , Fabaceae/microbiologia , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Glycine maxRESUMO
BACKGROUND: Sunflower is an important oilseed crop domesticated in North America approximately 4000 years ago. During the last century, oil content in sunflower was under strong selection. Further improvement of oil properties achieved by modulating its fatty acid composition is one of the main directions in modern oilseed crop breeding. RESULTS: We searched for the genetic basis of fatty acid content variation by genotyping 601 inbred sunflower lines and assessing their lipid and fatty acid composition. Our genome-wide association analysis based on the genotypes for 15,483 SNPs and the concentrations of 23 fatty acids, including minor fatty acids, revealed significant genetic associations for eleven of them. Identified genomic regions included the loci involved in rare fatty acids variation on chromosomes 3 and 14, explaining up to 34.5% of the total variation of docosanoic acid (22:0) in sunflower oil. CONCLUSIONS: This is the first large scale implementation of high-throughput lipidomic profiling to sunflower germplasm characterization. This study contributes to the genetic characterization of Russian sunflower collections, which made a substantial contribution to the development of sunflower as the oilseed crop worldwide, and provides new insights into the genetic control of oil composition that can be implemented in future studies.
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Ácidos Graxos/análise , Helianthus , Óleos de Plantas/análise , Estudos de Associação Genética , Genótipo , Helianthus/genética , América do Norte , Melhoramento Vegetal , Federação RussaRESUMO
A rotation sensor is one of the key elements of inertial navigation systems and compliments most cell phone sensor sets used for various applications. Currently, inexpensive and efficient solutions are mechanoelectronic devices, which nevertheless lack long-term stability. Realization of rotation sensors based on spins of fundamental particles may become a drift-free alternative to such devices. Here, we carry out a proof-of-concept experiment, demonstrating rotation measurements on a rotating setup utilizing nuclear spins of an ensemble of nitrogen vacancy centers as a sensing element with no stationary reference. The measurement is verified by a commercially available microelectromechanical system gyroscope.
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Blackleg and soft rot of potato (Solanum tuberosum) were monitored in the Central European part of Russia within a period of 2012- 2019. Symptoms included decay of tubers, blackening of stem vascular bundles, and partial yellowing of leaves. The disease causes serious potato yield losses in the field and storage. Pectobacterium parmentieri, P. brasiliense, P. versatile (syn. Ca. Pectobacterium maceratum), P. carotovorum, P. atrosepticum, Dickeya dianthicola, and D. solani are considered as main causal agents of soft rot and blackleg disease in Russia (Voronina et al. 2019, Ngoc Ha et al., 2019, Shirshikov et al. 2018, Kornev et al. 2012). Potato plant samples collected in commercial fields in routine plant health assay were used for bacteria isolation on crystal violet pectate agar (CVP) (Helias et al. 2012) as described previously (Voronina et al. 2019). Bacterial colonies producing pitting on CVP were re-isolated and purified on nutrient broth yeast extract medium. DNA of bacterial isolates was extracted, and polymerase chain reaction (PCR) amplifications were performed using gapA primers (Cigna et al. 2017) followed by sequencing. DNA sequence alignment showed that the isolates F099, F100, F106, F109, and F118 were identical (deposited as part of NCBI Ref.Seq. for F109 NZ_RRYS01000004.1, locus KHDHEBDM_RS06360) and grouped together with the type strain Pectobacterium polaris NIBIO1006T (CP017481), a new species described as a potato pathogen (Dees et al. 2017). These strains were negative in diagnostic PCR assays using specific primers Y45/Y46 for the detection of P. atrosepticum, Br1f and L1r for P. brasiliense (Duarte et al. 2004), and ADE1/ADE2 for Dickeya sp. (Nassar et al. 1996). To further validate the identification, strain F109 of P. polaris was selected for genome sequencing. The genome of P. polaris strain F109, (NCBI Reference Sequence NZ_RRYS00000000.1) reveals >99% sequence similarity with type strain P. polaris IPO_1606 (GenBank accession GCA_902143345.1). The strain F109 was deposited to All-Russian Collection of Microorganisms under number VKM V-3420. Thus, the characterization of five isolates provided evidence that a previously unreported pathogen was present in the surveyed fields. The isolates were uniform in genetic and physiological properties; they were gram negative, facultative anaerobes with pectinolytic activity, negative for oxidase, urease, indole production, gelatin liquefaction. All isolates were catalase positive, produced acid from lactose, rhamnose, saccharose, xylose, and trehalose, and were tolerant to 5% NaCl, unable to utilize malonate and citrate. All the isolates grew at 37°C. All isolates caused soft rot symptoms on 10 inoculated potato tubers. They produced typical black leg rot symptoms in young potato plants inoculated with 107 CFU/ml of the pathogen by stem injection and incubated at 25°C for 48 h. The bacteria were re-isolated successfully from symptomatic potato and pathogen confirmed by gapA sequencing to complete Koch's postulates. To our knowledge, this is the first report of blackleg and soft rot caused by P. polaris on potato in the Russian Federation. According to the data of commercial diagnostic laboratory "PhytoEngineering" (Moscow region), P. polaris occurred in 5% potato seed stocks harvested in 2017-2019 in the Moscow region. This finding may indicate that new Pectobacterium strains have adapted to a diverse environment, which is consistent with widespread distribution of commercial seed potatoes. The author(s) declare no conflict of interest. Funding: This work was supported by Russian Science Foundation grant #16-16-00073.
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Cytochrome c3 (uranyl reductase) from Desulfovibrio vulgaris can reduce uranium in bacterial cells and in cell-free systems. This gene was introduced in tobacco under control of the RbcS promoter, and the resulting transgenic plants accumulated uranium when grown on a uranyl ion containing medium. The uptaken uranium was detected by EM in chloroplasts. In the presence of uranyl ions in sublethal concentration, the transgenic plants grew phenotypically normal while the control plants' development was impaired. The data on uranium oxidation state in the transgenic plants and the possible uses of uranium hyperaccumulation by plants for environmental cleanup are discussed.
Assuntos
Grupo dos Citocromos c/genética , Desulfovibrio vulgaris/metabolismo , Nicotiana/crescimento & desenvolvimento , Compostos de Urânio/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Biodegradação Ambiental , Cloroplastos , Grupo dos Citocromos c/metabolismo , Engenharia Genética , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/metabolismo , Regiões Promotoras Genéticas , Nicotiana/genética , Nicotiana/metabolismoRESUMO
Discovery of the B7 family immune checkpoints such as CTLA-4 (CD152), PD-1 (CD279), as well as their ligands B7-1 (CD80), B7-2 (CD86), B7-H1 (PD-L1, CD274), and B7-DC (PD-L2, CD273), has opened new possibilities for cancer immunotherapy using monoclonal antibodies (mAb). The blockade of inhibitory receptors (CTLA-4 and PD-1) with specific mAb results in the activation of cancer patients' T lymphocytes and tumor rejection. However, the use of mAb in clinics has several limitations including side effects and cost of treatment. The development of new low-molecular compounds that block immune checkpoints' functional activity can help to overcome some of these limitations. In this paper, we describe a synthetic peptide (p344) containing 14 amino acids that specifically interact with CTLA-4 protein. A 3D computer model suggests that this peptide binds to the 99MYPPPY104 loop of CTLA-4 protein and potentially blocks the contact of CTLA-4 receptor with B7-1 ligand. Experimental data confirm the peptide-specific interaction with CTLA-4 and its ability to partially block CTLA-4/B7-1 binding. The identified synthetic peptide can be used for the development of novel immune checkpoint inhibitors that can block CTLA-4 functional activity for cancer immunotherapy.
Assuntos
Antígeno CTLA-4 , Inibidores de Checkpoint Imunológico , Proteínas de Neoplasias , Neoplasias/tratamento farmacológico , Peptídeos , Antígeno B7-1/antagonistas & inibidores , Antígeno B7-1/química , Antígeno B7-1/metabolismo , Antígeno CTLA-4/antagonistas & inibidores , Antígeno CTLA-4/química , Antígeno CTLA-4/metabolismo , Humanos , Inibidores de Checkpoint Imunológico/química , Inibidores de Checkpoint Imunológico/farmacologia , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/química , Proteínas de Neoplasias/metabolismo , Neoplasias/química , Neoplasias/metabolismo , Peptídeos/química , Peptídeos/farmacologiaRESUMO
MicroRNAs, which circulate in blood, are characterized by high diagnostic value; in biomedical research, they can be considered as candidate markers of various diseases. Mature microRNAs of glial cells and neurons can cross the blood-brain barrier and can be detected in the serum of patients with autism spectrum disorders (ASD) as components of macrovesicles, macromolecular protein and low-density lipoprotein particles. In our present study, we have proposed an approach, in which microRNAs in protein complexes can be concentrated on the surface of AFM chips with oligonucleotide molecular probes, specific against the target microRNAs. MicroRNAs, associated with the development of ASD in children, were selected as targets. The chips with immobilized molecular probes were incubated in serum samples of ASD patients and healthy volunteers. By atomic force microscopy (AFM), objects on the AFM chip surface have been revealed after incubation in the serum samples. The height of these objects amounted to 10 nm and 6 nm in the case of samples of ASD patients and healthy volunteers, respectively. MALDI-TOF-MS analysis of protein components on the chip surface allowed us to identify several cell proteins. These proteins are involved in the binding of nucleic acids (GBG10, RT24, RALYL), in the organization of proteasomes and nucleosomes (PSA4, NP1L4), and participate in the functioning of the channel of active potassium transport (KCNE5, KCNV2).
Assuntos
Transtorno do Espectro Autista/sangue , Proteínas Sanguíneas/genética , MicroRNA Circulante/sangue , Microscopia de Força Atômica/instrumentação , Adulto , Proteínas Sanguíneas/metabolismo , Criança , MicroRNA Circulante/metabolismo , Feminino , Humanos , Masculino , Microscopia de Força Atômica/métodos , Pessoa de Meia-Idade , Canais de Potássio de Abertura Dependente da Tensão da Membrana/sangue , Canais de Potássio de Abertura Dependente da Tensão da Membrana/genética , Canais de Potássio de Abertura Dependente da Tensão da Membrana/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por MatrizRESUMO
An obligately alkaliphilic, anaerobic, proteolytic bacterium was isolated from a sample of Tanatar III soda lake sediment (Altai region, Russia) and designated as strain Z-1701T. Cells of strain Z-1701T were short, straight, motile Gram-stain-positive rods. Growth of Z-1701T obligately depended on the presence of sodium carbonate. Strain Z-1701T could utilize various peptides mixtures, such as beef and yeast extracts, peptone, soytone, trypticase and tryptone, as well as such proteins as albumin, gelatin and sodium caseinate. It was able to grow oligotrophically with 0.02 g l-1 yeast extract as the sole energy and carbon source. Carbohydrates did not support the growth of strain Z-1701T. The main products released during the growth of strain Z-1701T on tryptone were formate, acetate and ammonium. Strain Z-1701T was able to reduce ferrihydrite, Fe(III)-EDTA, anthraquinone-2,6-disulfonate and elemental sulfur, using proteinaceous substrates as electron donors. In all cases the presence of the electron acceptor in the medium stimulated growth. The main cellular fatty acids were iso-C15â:â0, iso-C15â:â0 aldehyde, iso-C15â:â1 ω6, C16â:â0, iso-C17â:â0 aldehyde, C16â:â0 aldehyde and C14â:â0. The DNA G+C content of the isolate was 43.9 mol%. Phylogenetic analysis based on the concatenated alignment of 120 protein-marker sequences revealed that strain Z-1701T falls into a cluster with the genus Tindallia, family Clostridiaceae. 16S rRNA gene sequence identity between strain Z-1701T and Tindallia species were 88.3-89.75â%. On the basis of its phenotypic characteristics and phylogenetic position, the novel isolate is considered to be a representative of a novel genus and species for which the name Isachenkonia alkalipeptolytica gen. nov., sp. nov. is proposed, with Z-1701T (=JCM 32929Т=DSM 109060Т=VKM B-3261Т) as its type strain.
Assuntos
Bactérias Anaeróbias/classificação , Compostos Férricos/metabolismo , Lagos/microbiologia , Filogenia , Bactérias Redutoras de Enxofre/classificação , Álcalis , Bactérias Anaeróbias/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Bacilos Gram-Positivos/classificação , Bacilos Gram-Positivos/isolamento & purificação , Concentração de Íons de Hidrogênio , RNA Ribossômico 16S/genética , Federação Russa , Análise de Sequência de DNA , Enxofre/metabolismo , Bactérias Redutoras de Enxofre/isolamento & purificaçãoRESUMO
A novel aerobic moderately thermophilic bacterium, strain 3753OT, was isolated from a Chukotka hot spring (Arctic, Russia) using the newly developed technology of laser engineering of microbial systems. Сells were regular short rods, 0.4×0.8-2.0 µm in size, with a monoderm-type envelope and a single flagellum. The temperature and pH ranges for growth were 42-60 °C and pH 6.5-8.5, the optima being 50-54 °C and pH 7.3. Strain 3753OT grew chemoorganoheterotrophically on a number of carbohydrates or peptidic substrates and volatile fatty acids, and chemolithoautotrophically with siderite (FeCO3) as the electron donor. The major cellular fatty acid was branched C19â:â0. Phosphatidylethanolamine, phosphatidylglycerol and two unidentified phospholipids as well as two yellow carotenoid-type pigments were detected in the polar lipid extract. Strain 3753OT was inhibited by chloramphenicol, polymyxin B, vancomycin, streptomycin, neomycin and kanamycin, but resistant to the action of novobiocin and ampicillin. The DNA G+C content was 69.9 mol%. The 16S rRNA gene as well as 51 conservative protein sequence-based phylogenetic analyses placed strain 3753OT within the previously uncultivated lineage OLB14 in the phylum Chloroflexi. Taking into account the phylogenetic position as well as phenotypic properties of the novel isolate, the novel genus and species Tepidiforma bonchosmolovskayae gen. nov., sp. nov., within the Tepidiformaceae fam. nov., the Tepidiformales ord. nov. and the Tepidiformia classis nov. are proposed. The type strain of Tepidiforma bonchosmolovskayae is 3753OT (=VKM B-3389T=KTCT 72284T).
Assuntos
Chloroflexi/classificação , Fontes Termais/microbiologia , Filogenia , Regiões Árticas , Técnicas de Tipagem Bacteriana , Composição de Bases , Carotenoides/química , DNA Bacteriano/genética , Ácidos Graxos/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Federação Russa , Análise de Sequência de DNARESUMO
A series of benzotriazole, cyclic amides and pyrimidine derivatives, containing 2,6-di-tert-butyl-phenol fragments, were synthesized. The redox properties of obtained compounds were studied using the cyclic voltammetry on a platinum electrode in acetonitrile. The oxidation potentials of all substances were comparable to those of BHT. The obtained compounds were tested for their antibacterial activity, and N-(2-(3,5-di-tert-butyl-4-hydroxyphenyl)-2-oxoethyl)isatin (32 µg/mL) exerted good activity against Staphylococcus aureus.
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Antibacterianos/química , Antioxidantes/química , Fenóis/química , Amidas/química , Antibacterianos/farmacologia , Antioxidantes/farmacologia , Humanos , Oxirredução/efeitos dos fármacos , Fenóis/síntese química , Fenóis/isolamento & purificação , Fenóis/farmacologia , Pirimidinas/química , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/patogenicidade , Triazóis/químicaRESUMO
The Pot, Atom, and Step Economy (PASE) approach is based on the Pot economy principle and unites it with the Atom and Step Economy strategies; it ensures high efficiency, simplicity and low waste formation. The PASE approach is widely used in multicomponent chemistry. This approach was adopted for the synthesis of previously unknown hydroxyquinolinone substituted chromeno[2,3-b]pyridines via reaction of salicylaldehydes, malononitrile dimer and hydroxyquinolinone. It was shown that an ethanol-pyridine combination is more beneficial than other inorganic or organic catalysts. Quantum chemical studies showed that chromeno[2,3-b]pyridines has potential for corrosion inhibition. Real time 1H NMR monitoring was used for the investigation of reaction mechanism and 2-((2H-chromen-3-yl)methylene)malononitrile was defined as a key intermediate in the reaction.
Assuntos
Aldeídos/química , Técnicas de Química Sintética , Piridinas/química , Quinolonas/química , Solventes/química , Catálise , Dimerização , Etanol/química , Hidroxiquinolinas/química , Espectroscopia de Ressonância Magnética , Nitrilas/química , Teoria QuânticaRESUMO
Oral applications of peroxidised sunflower oil (PSO) cause development of nephropathy, which can be prevented with the help of oral applications of the Biotrit phytogel containing bioflavonoids from wheat seedlings. The purpose of this work was to determine the renoprotective effect of the Biotrit phytogel under the influence of PSO on rats. The experiments were carried out on 18 white Wistar rats (females, 4-5 months, 210±12 g), divided into 3 equal groups: the first - control, received compound feed. The 2nd and 3rd groups received the same diet; however, they additionally undergo oral applications of PSO at a dose of 0.5 ml per rat daily for 5 days. Rats of the 3rd group 30 minutes before the application of PSO received application of the "Biotrit" gel in a dose of 0.5 ml per rat for 5 days. After euthanasia of animals, kidneys were removed on the 6th day and the level of biochemical markers of inflammation and the content of malonic dialdehyde (MDA), urease and lysozyme were determined in the homogenate of the latter. Under the action of PSO both indicators significantly increase: elastase activity by 20%, and MDA content by 50%. Oral applications of the "Biotrit" gel reduce both indicators of inflammation. Catalase activity does not change both with the introduction of PSO and after application of the Biotrit gel. In rats treated with PSO, urease activity in the kidneys significantly increases, indicating an increase in bacterial contamination, which decreases under the influence of oral applications of the Biotrit gel. The consumption of peroxidised fats causes the development of nephropathy in experimental animals. To prevent the development of peroxide nephropathy, one can use oral applications of "Biotrit" phytogel.