Publications by authors named "Ursula Steffens"

Cervimycins A-D are bis-glycosylated polyketide antibiotics produced by HKI 0179 with bactericidal activity against Gram-positive bacteria. In this study, cervimycin C (CmC) treatment caused a spaghetti-like phenotype in 168, with elongated curved cells, which stayed joined after cell division, and exhibited a chromosome segregation defect, resulting in ghost cells without DNA. Electron microscopy of CmC-treated (3 × MIC) revealed swollen cells, misshapen septa, cell wall thickening, and a rough cell wall surface.

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Genomic and functional analyses of bacterial sponge symbionts belonging to the uncultivated candidate genus 'Entotheonella' has revealed them as the prolific producers of bioactive compounds previously identified from their invertebrate hosts. These studies also suggested 'Entotheonella' as the first members of a new candidate phylum, 'Tectomicrobia'. Here we analyzed the phylogenetic structure and environmental distribution of this as-yet sparsely populated phylum-like lineage.

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Resistance to antibiotics is an increasing problem and necessitates novel antibacterial therapies. The polyketide antibiotics cervimycin A to D are natural products of Streptomyces tendae HKI 0179 with promising activity against multidrug-resistant staphylococci and vancomycin-resistant enterococci. To initiate mode of action studies, we selected cervimycin C- and D-resistant (CmR) Staphylococcus aureus strains.

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The genetic plasticity of Staphylococcus aureus has facilitated the evolution of many virulent and drug-resistant strains. Here we present the sequence of the 2.74 Mbp genome of S.

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Cultivated bacteria such as actinomycetes are a highly useful source of biomedically important natural products. However, such 'talented' producers represent only a minute fraction of the entire, mostly uncultivated, prokaryotic diversity. The uncultured majority is generally perceived as a large, untapped resource of new drug candidates, but so far it is unknown whether taxa containing talented bacteria indeed exist.

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