Publications by authors named "Victoria Shcherbakova"

Macozinone (MCZ; PBTZ169) is a first-in-class antituberculosis clinical-stage benzothiazinone-based drug candidate. Although its efficacy and safety have been strongly proven in several preclinical and clinical studies, the physicochemical and pharmacokinetic properties specific to MCZ required further optimization. Accordingly, this study aimed to evaluate the pharmacokinetics of MCZ administered as extended-release (ER) tablets F2 and F6 compared to immediate-release (IR) dispersible tablets for oral suspension.

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A strain of obligately anaerobic, spore-forming, Gram-positive rods was isolated from child faeces and characterized both phenotypically and genotypically. Phylogenetic analysis based on 16S rRNA gene and whole genome sequencing revealed the strain to represent a member of the family distant from described species and genera. The strain was moderately saccharolytic with mannose as the preferred substrate and produced lactic acid, acetic acid and H as the end products.

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A strain of obligately anaerobic, Gram-stain-negative rods was isolated from human faeces and characterized both phenotypically and genotypically. Phylogenetic analysis based on 16S rRNA gene and whole-genome sequences revealed the strain to represent a member of the genus Prevotella, distant from the species with validly published names, with the closest relationship to Prevotella oryzae. The strain was moderately saccharolytic and proteolytic.

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Polar permafrost is at the forefront of climate change, yet only a few studies have enriched the native methane-producing microbes that might provide positive feedbacks to climate change. Samples Ant1 and Ant2, collected in Antarctic Miers Valley from permafrost sediments, with and without biogenic methane, respectively, were evaluated for methanogenic activity and presence of methanogens. After a one-year incubation of both samples under anaerobic conditions, methane production was observed only at room temperature in microcosm Ant1 with CO2/H2 (20/80) as carbon and energy sources and was monitored during the subsequent 10 years.

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A genomic reconstruction belonging to the genus Methanosarcina was assembled from metagenomic data from a methane-producing enrichment of Antarctic permafrost. This is the first methanogen genome reported from permafrost of the Dry Valleys and can help shed light on future climate-affected methane dynamics.

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A study of the faecal microbiome in three healthy female rhesus macaques revealed the presence of a novel obligately anaerobic, chemoorganoheterotrophic, non-sporing, coccoid, non-motile, Gram-stain-positive bacterial species. Three strains of this species, designated as M108T, M916-1/1, and M919-2/1, were non-haemolytic, H2S-positive, catalase-positive, bile- and NaCl-sensitive and required peptone for growth. Strains also were asaccharolytic, able to utilize sulfite, thiosulfate and elemental sulfur as electron acceptors, and produced acetic and butyric acids as metabolic end-products.

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Article Synopsis
  • - The study investigated the diversity of methanogenic archaea in five permafrost samples from Russia using culture-independent methods, revealing that 60%-95% of the DNA sequences belonged to the Euryarchaeota group.
  • - Researchers identified novel methanogenic archaea from various orders such as Methanosarcinales and Methanomicrobiales, while non-methanogenic Bathyarchaeota species were found in all samples.
  • - The highest diversity of archaea was noted at a depth of 22.3 meters, likely due to the presence of organic carbon and microbial cell migration during freezing.
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Two novel strains of Gram-stain-negative, rod-shaped, obligately anaerobic, non-spore-forming, non-motile bacteria were isolated from the faeces of healthy human subjects. The strains, designated as 585-1T and 668, were characterized by mesophilic fermentative metabolism, production of d-lactic acid, succinic acid and acetic acid as end products of d-glucose fermentation, prevalence of C18 : 1ω9, C18 : 1ω9 aldehyde, C16 : 0 and C16 : 1ω7c fatty acids, presence of glycine, glutamic acid, lysine, alanine and aspartic acid in the petidoglycan peptide moiety and lack of respiratory quinones. Whole genome sequencing revealed the DNA G+C content was 56.

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Culture-based study of the faecal microbiome in two adult female subjects revealed the presence of two obligately anaerobic, non-spore-forming, rod-shaped, non-motile, Gram-negative bacterial strains that represent novel species. The first strain, designated 627T, was a fastidious, slow-growing, indole-positive bacterium with a non-fermentative type of metabolism.The strain was characterized by the production of acetic and succinic acids as metabolic end products, the prevalence of iso-C15 : 0 fatty acid and the presence of menaquinones MK-10 and MK-11.

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A novel haloalkaliphilic sulfate-reducing bacterium, designated Al915-01(T), was isolated from benthic sediments of the Lake Alginskoe, a soda lake located in the Trans-Baikal Region, Russia. Cells of the strain were Gram-stain negative, motile, non-spore-forming vibrion (0.4-0.

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New strains of sulfate-reducing bacteria were isolated from two alkaline brackish lakes located in the Siberian region of Russia, namely in the Southern Transbaikalia, Buriatia. The article presents data describing morphology, physiology, and biochemical characteristics of the isolated strains. These strains Ki4, Ki5, and Su2 were mesophilic and alkaliphilic with optimal growth at pH 8.

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A novel obligately anaerobic, non-spore-forming, rod-shaped, non-motile Gram-reaction-negative bacterium was isolated from infant faeces. The strain, designated NSB1(T), was able to grow on rich media at 30-37 °C, in the presence of up to 2 % (w/v) Oxgall and 2 % (w/v) NaCl. Cells of strain NSB1(T) produced catalase, but not urease and indole.

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A novel constituent of bacterial polysaccharides, 2,3,4-triacetamido-2,3,4-trideoxy-L-arabinose, was found in the O-specific polysaccharide from the lipopolysaccharide of Psychrobacter cryohalolentis K5(T) and identified by 1D and 2D (1)H and (13)C NMR studies of the polysaccharide and a disaccharide obtained by solvolysis of the polysaccharide with triflic acid. The following structure of the branched polysaccharide was established by sugar analysis, triflic acid solvolysis, Smith degradation, and 2D NMR spectroscopy.

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An acidic polysaccharide was obtained from Psychrobacter maritimus 3pS isolated from a Siberian cryopeg sample (Kolyma lowland). The following structure of the tetrasaccharide repeating unit of the polysaccharide was established by sugar analysis along with (1)H and (13)C NMR spectroscopy: →2)-α-L-Rhap-(1→4)-α-D-GalpNAcA-(1→3)-α-D-QuipNAc4NHb-(1→3)-β-D-QuipNAc4NHb-(1→ where D-GalNAcA indicates 2-acetamido-2-deoxy-D-galacturonic acid and d-QuiNAc4NHb indicates 2-acetamido-2,4,6-trideoxy-4-[(S)-3-hydroxybutanoyl]amino-D-glucose.

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Psychrotrophic bacteria of the genus Psychrobacter have not been studied in respect to lipopolysaccharide structure. In this work, we determined the structure of the O-specific polysaccharide of the lipopolysaccharide of Psychrobacter muricolla 2pS(T) isolated from overcooled (-9°C) water brines within permafrost. The polysaccharide was found to be acidic due to the presence of an amide of 2-acetamido-2-deoxy-l-guluronic acid with glycine (l-GulNAcA6Gly), which has not been hitherto found in nature.

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