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71.
ABSTRACTThere is an increasing interest in the Eustigmatophyceae, a class of stramenopile microalgae, because they offer a variety of high-value health-beneficial compounds, e.g. polyunsaturated fatty acids (PUFAs), while concomitantly producing high biomass. Clarification of the taxonomy of these organisms at the species level is important in order to achieve reproducible results and constant yields of valuable compounds in their exploitation. Here the distinction of the, so far exclusively, morphologically defined species of the genera Eustigmatos and Vischeria was tested. Distinctions inferred from almost full 18S and ITS2 rRNA as well as plastid-encoded rbcL gene sequences were evaluated following a morphological investigation. The ITS2 secondary-structure-based phylogenies separated independent lineages (species) with long internal branches. This recommends ITS2 as a promising marker for a DNA metabarcoding approach (culture-independent biodiversity assessment). In contrast, the 18S V4 region which is commonly used in metabarcoding was almost invariant, whereas the almost full length sequences distinguished eight groups/types of strains. Monophyly of the species was supported by shared ITS2 secondary structure features, making them distinct from other eustigmatophyte lineages in concordance with phylogenetic analyses. No groups of strains were congruently supported by all three markers. Consequently, the previous distinction of two genera on the basis of morphology cannot be retained and the species should be accommodated in a single genus, Vischeria. Taxonomic changes among the species with the definition of epitypes, on the basis of cryopreserved strains, are recommended. Two findings point to a more complex evolutionary history of the species. The rbcL and nuclear markers resulted in disparate groupings of strains. In three species divergent intragenomic ITS2 paralogues were revealed. Therefore, a still broader taxon sampling, in conjunction with a deep sequencing approach, is needed for a more comprehensive understanding of the complex evolution of eustigmatophyte species. 相似文献
72.
Zubareva OE Shcherbakova KP Kalemenev SV Simbirtsev AS Klimenko VM 《Zhurnal vysshe? nervno? deiatelnosti imeni I P Pavlova》2011,61(6):736-741
Impairments of cognitive functions in children and adolescents are often consequences ofperinatal pathology (natal injuries, ischemia, hypoxia, infection and allergic diseases), which are accompanied by enhanced production ofproinflammatory cytokine interleukine-1beta. In this work it was shown that treatment with interleukine-1beta during the third week of life impaired active and passive avoidance conditioning in adult rats at the age of 60-70 days. 相似文献
73.
S. A. Pecheritsyna V. A. Shcherbakova A. L. Kholodov V. N. Akimov T. N. Abashina N. E. Suzina E. M. Rivkina 《Microbiology》2007,76(5):614-620
The paper deals with the microbiological characterization of water-saturated horizons in permafrost soils (cryopegs) found on the Varandei Peninsula (Barents Sea coast), 4–20 m deep. The total quantity of bacteria in the water of cryopegs was 3.5 × 108 cells/ml. The population of cultivated aerobic heterotrophic bacteria was 3–4 × 107 cells/ml and the number of anaerobic heterotrophic bacteria varied from 102 to 105 cells/ml depending on cultivation temperature and salinity. Sulfate-reducing bacteria and methanogenic archaea were found as hundreds and tens of cells per ml of water, respectively. A pure culture of a sulfate-reducing strain B15 was isolated from borehole 21 and characterized. Phylogenetic analysis has shown that the new bacterium is a member of the genus Desulfovibrio with Desulfovibrio mexicanus as its closest relative (96.5% similarity). However, the significant phenotypic differences suggest that strain B15 is a new species of sulfate-reducing bacteria. 相似文献
74.
Savateev K. V. Rusinov V. L. Kotovskaya S. K. Spasov A. A. Naumenko L. V. Taran A. S. Brigadirova A. A. Yakovlev D. S. Sultanova K. T. Shcherbakova N. M. 《Russian Journal of Bioorganic Chemistry》2022,48(4):777-782
Russian Journal of Bioorganic Chemistry - Six compounds of the 5(7)-alkylamino-6-nitroazolopyrimidine and 8-alkylazolo[5,1-b]purine series were selected based on the structural analysis of A1... 相似文献
75.
76.
Vera I. Safronova Anastasiia K. Kimeklis Elena P. Chizhevskaya Andrey A. Belimov Evgeny E. Andronov Alexander G. Pinaev Andrey R. Pukhaev Konstantin P. Popov Igor A. Tikhonovich 《Antonie van Leeuwenhoek》2014,105(2):389-399
Sixteen bacterial strains were isolated from root nodules of Vavilovia formosa plants originated from the North Ossetian State Natural Reserve (Caucasus, Russia). Phylogenetic analysis of these strains was performed using partial 16S rRNA gene and internally transcribed spacer (ITS) sequences. The results showed that the isolates belong to three families of root nodule bacteria. Twelve of them were related to the genus Rhizobium (family Rhizobiaceae) but four strains can be most probably identified as Phyllobacterium-related (family Phyllobacteriaceae), Bosea- and Rhodopseudomonas-related (family Bradyrhizobiaceae). Amplified fragment length polymorphism clustering was congruent with ITS phylogeny but displayed more variability for Rhizobium isolates, which formed a single group at the level of 30 % similarity. We expect that the isolates obtained can belong to new taxa at genus, species or subspecies levels. The results of PCR amplification of the nodulation genes nodC and nodX showed their presence in all Rhizobium isolates and one Rhodopseudomonas-related isolate. The nodC gene sequences of V. formosa isolates were closely related to those of the species Rhizobium leguminosarum bv. viciae but formed separate clusters and did not intermingle with any reference strains. The presence of the nodX gene, which is necessary for nodulation of Afghan peas (Pisum sativum L.) originated from the Middle East, allows the speculation that these wild-type pea cultivars may be the closest existing relatives of V. formosa. Thus, the studies of genetic diversity and symbiotic genes of V. formosa microsymbionts provide the primary information about their phylogeny and contribute to the conservation of this relict leguminous species. 相似文献
77.
E. M. Sukhodol’skaya V. A. Vasil’ev D. V. Shibalev O. I. Shcherbakova A. M. Kulikov O. E. Lazebny D. A. Dronova M. L. Butovskaya A. P. Ryskov 《Molecular Biology》2014,48(2):254-257
A study of VNTR polymorphism and molecular structure of 3′-UTR of the dopamine transporter gene (DAT1/SLC6A3) was performed in the Hadza and Datoga males. It was shown that Hadza and Datoga differed in allele and genotype frequencies. Allele with 9 repeats in 3′-UTR, as well as the DAT1 homozygous genotype 9/9, is more common in the Hadza. The allele with ten repeats, as well as the homozygous phenotype 10/10, is more common in the Datoga. Molecular structure of DAT1 alleles with 3, 8, and 12 repeats was determined for the first time. In addition, it was found that the DAT1 allele with 11 repeats in the Datoga significantly differed in the type and arrangement of repeats from those previously described in other populations. We suggest that variations in the repeats number and type in the 3′-UTR of allelic variants may affect the dopamine transporter gene function. 相似文献
78.
Eric N. Senning Marcus D. Collins Anastasiia Stratiievska Carmen A. Ufret-Vincenty Sharona E. Gordon 《The Journal of biological chemistry》2014,289(16):10999-11006
Membrane asymmetry is essential for generating second messengers that act in the cytosol and for trafficking of membrane proteins and membrane lipids, but the role of asymmetry in regulating membrane protein function remains unclear. Here we show that the signaling lipid phosphoinositide 4,5-bisphosphate (PI(4,5)P2) has opposite effects on the function of TRPV1 ion channels depending on which leaflet of the cell membrane it resides in. We observed potentiation of capsaicin-activated TRPV1 currents by PI(4,5)P2 in the intracellular leaflet of the plasma membrane but inhibition of capsaicin-activated currents when PI(4,5)P2 was in both leaflets of the membrane, although much higher concentrations of PI(4,5)P2 in the extracellular leaflet were required for inhibition compared with the concentrations of PI(4,5)P2 in the intracellular leaflet that produced activation. Patch clamp fluorometry using a synthetic PI(4,5)P2 whose fluorescence reports its concentration in the membrane indicates that PI(4,5)P2 must incorporate into the extracellular leaflet for its inhibitory effects to be observed. The asymmetry-dependent effect of PI(4,5)P2 may resolve the long standing controversy about whether PI(4,5)P2 is an activator or inhibitor of TRPV1. Our results also underscore the importance of membrane asymmetry and the need to consider its influence when studying membrane proteins reconstituted into synthetic bilayers. 相似文献
79.
80.
Cyrille P. Launay Laure de Decker Anastasiia Kabeshova Cédric Annweiler Olivier Beauchet 《PloS one》2014,9(10)