23 research outputs found

    En frankisk Korsfibel fra 9. ĂĄrhundrede fra Ribe

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    I 1990 blev der ved en udgravning i Ribe fundet et lille korsformet smykke af forgyldt bronze, der stammer fra Karolingerriget, og som kan dateres til 9. århundrede. Man bør regne den til et af de ældste arkæologiske spor efter kristne, som allerede på dette tidspunkt kan have levet på den vikingetidige handelsplads i det sydvestlige Jylland

    A Twist to the Kirby-Bauer Disk Diffusion Susceptibility Test: an Accessible Laboratory Experiment Comparing Haloferax volcanii and Escherichia coli Antibiotic Susceptibility to Highlight the Unique Cell Biology of Archaea

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    Archaea, once thought to only live in extreme environments, are present in many ecosystems, including the human microbiome, and they play important roles ranging from nutrient cycling to bioremediation. Yet this domain is often overlooked in microbiology classes and rarely included in laboratory exercises. Excluding archaea from high school and undergraduate curricula prevents students from learning the uniqueness and importance of this domain. Here, we have modified a familiar and popular microbiology experiment-the Kirby-Bauer disk diffusion antibiotic susceptibility test-to include, together with the model bacterium Escherichia coli, the model archaeon Haloferax volcanii. Students will learn the differences and similarities between archaea and bacteria by using antibiotics that target, for example, the bacterial peptidoglycan cell wall or the ribosome. Furthermore, the experiment provides a platform to reiterate basic cellular biology concepts that students may have previously discussed. We have developed two versions of this experiment, one designed for an undergraduate laboratory curriculum and the second, limited to H. volcanii, that high school students can perform in their classrooms. This nonpathogenic halophile can be cultured aerobically at ambient temperature in high-salt media, preventing contamination, making the experiment low-cost and safe for use in the high school setting

    Towards a holistic and solution-oriented monitoring of chemical status of European water bodies: how to support the EU strategy for a non-toxic environment?

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    Abstract The definition of priority substances (PS) according to the Water Framework Directive (WFD) helped to remove many of these chemicals from the market and to reduce their concentrations in the European water bodies. However, it could not prevent that many of these chemicals have been replaced by others with similar risks. Today, monitoring of the PS-based chemical status according to WFD covers only a tiny fraction of toxic risks, extensively ignores mixture effects and lacks incentives and guidance for abatement. Thus, we suggest complement this purely status-related approach with more holistic and solution-oriented monitoring, which at the same time helps to provide links to the ecological status. Major elements include (1) advanced chemical screening techniques supporting mixture risk assessment and unraveling of source-related patterns in complex mixtures, (2) effect-based monitoring for the detection of groups of chemicals with similar effects and the establishment of toxicity fingerprints, (3) effect-directed analysis of drivers of toxicity and (4) to translate chemical and toxicological fingerprints into chemical footprints for prioritization of management measures. The requirement of more holistic and solution-oriented monitoring of chemical contamination is supported by the significant advancement of appropriate monitoring tools within the last years. Non-target screening technology, effect-based monitoring and basic understanding of mixture assessment are available conceptually and in research but also increasingly find their way into practical monitoring. Substantial progress in the development, evaluation and demonstration of these tools, for example, in the SOLUTIONS project enhanced their acceptability. Further advancement, integration and demonstration, extensive data exchange and closure of remaining knowledge gaps are suggested as high priority research needs for the next future to bridge the gap between insufficient ecological status and cost-efficient abatement measures

    Enhancing Open Modification Searches via a Combined Approach Facilitated by Ursgal

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    The identification of peptide sequences and their post-translational modifications (PTMs) is a crucial step in the analysis of bottom-up proteomics data. The recent development of open modification search (OMS) engines allows virtually all PTMs to be searched for. This not only increases the number of spectra that can be matched to peptides but also greatly advances the understanding of the biological roles of PTMs through the identification, and the thereby facilitated quantification, of peptidoforms (peptide sequences and their potential PTMs). Whereas the benefits of combining results from multiple protein database search engines have been previously established, similar approaches for OMS results have been missing so far. Here we compare and combine results from three different OMS engines, demonstrating an increase in peptide spectrum matches of 8–18%. The unification of search results furthermore allows for the combined downstream processing of search results, including the mapping to potential PTMs. Finally, we test for the ability of OMS engines to identify glycosylated peptides. The implementation of these engines in the Python framework Ursgal facilitates the straightforward application of the OMS with unified parameters and results files, thereby enabling yet unmatched high-throughput, large-scale data analysis

    Identification of structural and regulatory cell-shape determinants in Haloferax volcanii

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    Abstract Archaea play indispensable roles in global biogeochemical cycles, yet many crucial cellular processes, including cell-shape determination, are poorly understood. Haloferax volcanii, a model haloarchaeon, forms rods and disks, depending on growth conditions. Here, we used a combination of iterative proteomics, genetics, and live-cell imaging to identify mutants that only form rods or disks. We compared the proteomes of the mutants with wild-type cells across growth phases, thereby distinguishing between protein abundance changes specific to cell shape and those related to growth phases. The results identified a diverse set of proteins, including predicted transporters, transducers, signaling components, and transcriptional regulators, as important for cell-shape determination. Through phenotypic characterization of deletion strains, we established that rod-determining factor A (RdfA) and disk-determining factor A (DdfA) are required for the formation of rods and disks, respectively. We also identified structural proteins, including an actin homolog that plays a role in disk-shape morphogenesis, which we named volactin. Using live-cell imaging, we determined volactin’s cellular localization and showed its dynamic polymerization and depolymerization. Our results provide insights into archaeal cell-shape determination, with possible implications for understanding the evolution of cell morphology regulation across domains

    German Cancer Consortium (DKTK) - a national consortium for translational cancer research

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    The German Cancer Consortium ('Deutsches Konsortium fĂĽr Translationale Krebsforschung', DKTK) is a long-term cancer consortium, bringing together the German Cancer Research Center (DKFZ), Germany's largest life science research center, and the leading University Medical Center-based Comprehensive Cancer Centers (CCCs) at seven sites across Germany. DKTK was founded in 2012 following international peer review and has positioned itself since then as the leading network for translational cancer research in Germany. DKTK is long term funded by the German Ministry of Research and Education and the federal states of each DKTK partner site. DKTK acts at the interface between basic and clinical cancer research, one major focus being to generate suitable multisite cooperation structures and provide the basis for including higher numbers of patients and facilitate effective collaborative forward and reverse translational cancer research. The consortium addresses areas of high scientific and medical relevance and develops critical infrastructures, for example, for omics technologies, clinical and research big data exchange and analysis, imaging, and clinical grade drug manufacturing. Moreover, DKTK provides a very attractive environment for interdisciplinary and interinstitutional training and career development for clinician and medical scientists
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