Taxonomic and typological features of the flora of the "Small Pinewood" ecological path in the "Lower Kama" National Park (Tatarstan)

The article deals with the taxonomic and eco-coenotic composition of the flora of "Small Pinewood" ecological path in the "Lower Kama" National Park (Tatarstan). Author analyzes the distribution of plants by the type of habitat, life forms, and eco-coenotic groups; presents data on the most prevalent families and analyzes the adventitious fraction of flora; identifies the most rare biomorphes composing flora, and evaluates the condition of the flora

High purity β-Bi2O3 preparation by thermal decomposition of tartrates

The processes of oxidative thermolysis of bismuth(III) DL-tartrate BiC4H3O6 obtained by the interaction of high-purity basic bismuth(III) nitrates [Bi6O4(OH)4](NO3)6·H2O and [Bi6O5(OH)3](NO3)5·3H2O with DL-tartaric acid solution have been investigated. The products of precipitation have been studied by methods of X-ray diffraction and thermal analysis, IR and Raman spectroscopy and chemical analysis. The staging of thermal transformation processes has been determined. Morphological studies and grain size analysis of initial precursors and final products of their thermal transformations have been carried out. The possibility of obtaining fine crystalline powders of tetragonal bismuth(III) oxide modification β-Bi2O3 by oxidative thermolysis of DL-BiC4H3O6 has been shown

USING WIND TURBINES TO GENERATE HEAT

In this article discusses one of the alternative renewable energy sources – wind energy. Its practical use is carried out with the help of wind motors. And below are a few different schemes of heat generation using these engines.В данной статье рассматривается один из альтернативных возобновляемых источников энергии – энергия ветра. Её практическое использование осуществляется с помощью ветряных двигателей. Представлены несколько различных схем выработки тепла с помощью данных двигателей

Poverty in the Russian Federation: Peculiarities and Ways of Overcoming

As the article implies the article describes the poverty in the Russian Federation. It is analyzed in detail the peculiarities of poverty in Russia. Much attention is given to a review of the possible ways of overcoming poverty.Анализируются причины возникновения бедности и особенности её существования в России. Предлагаются пути решения проблемы на основании опыта других государств. Автор приходит к выводу о том, что необходима разработка специальной программы для устранения бедности, которая подходит к российским условиям и особенностям, а также необходимо решать другие социальные проблемы, которые только усиливают дестабилизацию общества

Structural study of the type II 3-dehydroquinate dehydratase from Actinobacillus pleuropneumoniae

9 pages, 7 figures, 2 tables.The structure of the type II dehydroquinate dehydratase (DHQase) from Actinobacillus pleuropneumoniae, the third enzyme of the shikimate pathway, has been determined. Crystals diffracting to 1.7 Å were obtained in space and on earth using the counter-diffusion technique. The structure was solved using molecular replacement and refined to high resolution. The overall structure of the dodecameric enzyme is described and compared with structures of DHQases from other bacteria. DHQases contain a flexible loop that presumably closes over the active site upon substrate binding. The enzyme can exist in an open or closed conformation. The present structure displays the open conformation, with a sulfate anion bound in the active site. The availability of this structure opens a route to structure-based antibiotics targetting this pathogenic bacterium.We thank Professor Kabsch for providing XDS free of charge. We acknowledge the support of the European Space Agency and the European Community Action to Research Infrastructure Action of the Improving Human Potential Programme to the EMBL Hamburg Outstation, contract No. HPRI-CT-1999-00017. We thank Olivier Minster (ESA) for his support of space science. The authors acknowledge the excellent work of Dr Eva ManÄ as in managing the logistics concerning the space mission. We thank Viscount Dirk Frimout for his support for space crystallization experiments.Peer reviewe

Interaction of eukaryotic translation initiation factor 4G with the nuclear cap-binding complex provides a link between nuclear and cytoplasmic functions of the m7 guanosine cap

In eukaryotes the majority of mRNAs have an m7G cap that is added cotranscriptionally and that plays an important role in many aspects of mRNA metabolism. The nuclear cap-binding complex (CBC; consisting of CBP20 and CBP80) mediates the stimulatory functions of the cap in pre-mRNA splicing, 3' end formation, and U snRNA export. As little is known about how nuclear CBC mediates the effects of the cap in higher eukaryotes, we have characterized proteins that interact with CBC in HeLa cell nuclear extracts as potential mediators of its function. Using cross-linking and coimmunoprecipitation, we show that eukaryotic translation initiation factor 4G (eIF4G), in addition to its function in the cytoplasm, is a nuclear CBC-interacting protein. We demonstrate that eIF4G interacts with CBC in vitro and that, in addition to its cytoplasmic localization, there is a significant nuclear pool of eIF4G in mammalian cells in vivo. Immunoprecipitation experiments suggest that, in contrast to the cytoplasmic pool, much of the nuclear eIF4G is not associated with eIF4E (translation cap binding protein of eIF4F) but is associated with CBC. While eIF4G stably associates with spliceosomes in vitro and shows close association with spliceosomal snRNPs and splicing factors in vivo, depletion studies show that it does not participate directly in the splicing reaction. Taken together the data indicate that nuclear eIF4G may be recruited to pre-mRNAs via its interaction with CBC and accompanies the mRNA to the cytoplasm, facilitating the switching of CBC for eIF4F. This may provide a mechanism to couple nuclear and cytoplasmic functions of the mRNA cap structure

Immunization with the Haemophilus ducreyi Hemoglobin Receptor HgbA Protects against Infection in the Swine Model of Chancroid

The etiologic agent of chancroid is Haemophilus ducreyi. To fulfill its obligate requirement for heme, H. ducreyi uses two TonB-dependent receptors: the hemoglobin receptor (HgbA) and a receptor for free heme (TdhA). Expression of HgbA is necessary for H. ducreyi to survive and initiate disease in a human model of chancroid. In this study, we used a swine model of H. ducreyi infection to demonstrate that an experimental HgbA vaccine efficiently prevents chancroid, as determined by several parameters. Histological sections of immunized animals lacked typical microscopic features of chancroid. All inoculated sites from mock-immunized pigs yielded viable H. ducreyi cells, whereas no viable H. ducreyi cells were recovered from inoculated sites of HgbA-immunized pigs. Antibodies from sera of HgbA-immunized animals bound to and initiated antibody-dependent bactericidal activity against homologous H. ducreyi strain 35000HP and heterologous strain CIP542 ATCC; however, an isogenic hgbA mutant of 35000HP was not killed, proving specificity. Anti-HgbA immunoglobulin G blocked hemoglobin binding to the HgbA receptor, suggesting a novel mechanism of protection through the limitation of heme/iron acquisition by H. ducreyi. Such a vaccine strategy might be applied to other bacterial pathogens with strict heme/iron requirements. Taken together, these data suggest continuing the development of an HgbA subunit vaccine to prevent chancroid

Outline of a Genome Navigation System Based on the Properties of GA-Sequences and Their Flanks

Introducing a new method to visualize large stretches of genomic DNA (see Appendix S1) the article reports that most GA-sequences [1] shared chains of tetra-GA-motifs and contained upstream poly(A)-segments. Although not integral parts of them, Alu-elements were found immediately upstream of all human and chimpanzee GA-sequences with an upstream poly(A)-segment. The article hypothesizes that genome navigation uses these properties of GA-sequences in the following way. (1) Poly(A) binding proteins interact with the upstream poly(A)-segments and arrange adjacent GA-sequences side-by-side (‘GA-ribbon’), while folding the intervening DNA sequences between them into loops (‘associated DNA-loops’). (2) Genome navigation uses the GA-ribbon as a search path for specific target genes that is up to 730-fold shorter than the full-length chromosome. (3) As to the specificity of the search, each molecule of a target protein is assumed to catalyze the formation of specific oligomers from a set of transcription factors that recognize tetra-GA-motifs. Their specific combinations of tetra-GA motifs are assumed to be present in the particular GA-sequence whose associated loop contains the gene for the target protein. As long as the target protein is abundant in the cell it produces sufficient numbers of such oligomers which bind to their specific GA-sequences and, thereby, inhibit locally the transcription of the target protein in the associated loop. However, if the amount of target protein drops below a certain threshold, the resultant reduction of specific oligomers leaves the corresponding GA-sequence ‘denuded’. In response, the associated DNA-loop releases its nucleosomes and allows transcription of the target protein to proceed. (4) The Alu-transcripts may help control the general background of protein synthesis proportional to the number of transcriptionally active associated loops, especially in stressed cells. (5) The model offers a new mechanism of co-regulation of protein synthesis based on the shared segments of different GA-sequences

Quantitative analysis of ribosome–mRNA complexes at different translation stages

Inhibition of primer extension by ribosome–mRNA complexes (toeprinting) is a proven and powerful technique for studying mechanisms of mRNA translation. Here we have assayed an advanced toeprinting approach that employs fluorescently labeled DNA primers, followed by capillary electrophoresis utilizing standard instruments for sequencing and fragment analysis. We demonstrate that this improved technique is not merely fast and cost-effective, but also brings the primer extension inhibition method up to the next level. The electrophoretic pattern of the primer extension reaction can be characterized with a precision unattainable by the common toeprint analysis utilizing radioactive isotopes. This method allows us to detect and quantify stable ribosomal complexes at all stages of translation, including initiation, elongation and termination, generated during the complete translation process in both the in vitro reconstituted translation system and the cell lysate. We also point out the unique advantages of this new methodology, including the ability to assay sites of the ribosomal complex assembly on several mRNA species in the same reaction mixture