Die Schreiber der alt-türkischen Brāhmī-Texte

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The endoribonucleolytic N-terminal half of Escherichia coli RNase E is evolutionarily conserved in Synechocystis sp. and other bacteria but not the C-terminal half, which is sufficient for degradosome assembly

Escherichia coli RNase E, an essential single-stranded specific endoribonuclease, is required for both ribosomal RNA processing and the rapid degradation of mRNA. The availability of the complete sequences of a number of bacterial genomes prompted us to assess the evolutionarily conservation of bacterial RNase E. We show here that the sequence of the N-terminal endoribonucleolytic domain of RNase E is evolutionarily conserved in Synechocystis sp. and other bacteria. Furthermore, we demonstrate that the Synechocystis sp. homologue binds RNase E substrates and cleaves them at the same position as the E. coli enzyme. Taken together these results suggest that RNase E-mediated mechanisms of RNA decay are not confined to E. coli and its close relatives. We also show that the C-terminal half of E. coli RNase E is both sufficient and necessary for its physical interaction with the 3'-5' exoribonuclease polynucleotide phosphorylase, the RhlB helicase, and the glycolytic enzyme enolase, which are components of a "degradosome" complex. Interestingly, however, the sequence of the C-terminal half of E. coli RNase E is not highly conserved evolutionarily, suggesting diversity of RNase E interactions with other RNA decay components in different organisms. This notion is supported by our finding that the Synechocystis sp. RNase E homologue does not function as a platform for assembly of E. coli degradosome components

Discovery of a novel class of highly conserved vaccine antigens using genomic scale antigenic fingerprinting of pneumococcus with human antibodies

Pneumococcus is one of the most important human pathogens that causes life-threatening invasive diseases, especially at the extremities of age. Capsular polysaccharides (CPSs) are known to induce protective antibodies; however, it is not feasible to develop CPS-based vaccines that cover all of the 90 disease-causing serotypes. We applied a genomic approach and described the antibody repertoire for pneumococcal proteins using display libraries expressing 15–150 amino acid fragments of the pathogen's proteome. Serum antibodies of exposed, but not infected, individuals and convalescing patients identified the ANTIGENome of pneumococcus consisting of ∼140 antigens, many of them surface exposed. Based on several in vitro assays, 18 novel candidates were preselected for animal studies, and 4 of them showed significant protection against lethal sepsis. Two lead vaccine candidates, protein required for cell wall separation of group B streptococcus (PcsB) and serine/threonine protein kinase (StkP), were found to be exceptionally conserved among clinical isolates (>99.5% identity) and cross-protective against four different serotypes in lethal sepsis and pneumonia models, and have important nonredundant functions in bacterial multiplication based on gene deletion studies. We describe for the first time opsonophagocytic killing activity for pneumococcal protein antigens. A vaccine containing PcsB and StkP is intended for the prevention of infections caused by all serotypes of pneumococcus in the elderly and in children

A novel antisense RNA regulates at transcriptional level the virulence gene icsA of Shigella flexneri

The virulence gene icsA of Shigella flexneri encodes an invasion protein crucial for host colonization by pathogenic bacteria. Within the intergenic region virA-icsA, we have discovered a new gene that encodes a non-translated antisense RNA (named RnaG), transcribed in cis on the complementary strand of icsA. In vitro transcription assays show that RnaG promotes premature termination of transcription of icsA mRNA. Transcriptional inhibition is also observed in vivo by monitoring the expression profile in Shigella by real-time polymerase chain reaction and when RnaG is provided in trans. Chemical and enzymatic probing of the leader region of icsA mRNA either free or bound to RnaG indicate that upon hetero-duplex formation an intrinsic terminator, leading to transcription block, is generated on the nascent icsA mRNA. Mutations in the hairpin structure of the proposed terminator impair the RnaG mediated-regulation of icsA transcription. This study represents the first evidence of transcriptional attenuation mechanism caused by a small RNA in Gram-negative bacteria. We also present data on the secondary structure of the antisense region of RnaG. In addition, alternatively silencing icsA and RnaG promoters, we find that transcription from the strong RnaG promoter reduces the activity of the weak convergent icsA promoter through the transcriptional interference regulation

Policy agents as catalysts of knowledge links in the biotechnology sector

The purpose of this paper is to explore the role of public policy in promoting interorganisational knowledge links in the biotechnology sector. Despite the significance of such interactions and the policy efforts devoted to them, there is a limited understanding of how different initiatives from various policy levels contribute to the formation of specific knowledge linkages within the biotechnology industry. The paper identifies four main types of knowledge exchange, including market relations, spillovers, formal co-operations and informal networking. Drawing on evidence from the Vienna biotechnology cluster we intend to show how national and regional policy programmes and government actions function as mechanisms to stimulate the establishment of such interactions. (author's abstract)Series: SRE - Discussion Paper

Ueber Ortsbezeichnungen im Alttürkischen

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Die erste generation der forscher an den Turfan-Handschriften.

Donated by Klaus KreiserReprinted from : H. Klengel and W. Sundermann, eds., Ägypten Vorderasien Turfa

Iranische Elemente im zentral- und ostasiatischen Volksglauben

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Clusterentwicklung und -politik im Biotechnologiesektor Wien im Kontext internationaler Erfahrungen

(kein Autorenref. vorhanden)Series: SRE - Discussion Paper