Suchergebnisse

Since the Apollo 16 mission in 1972, Bacillus subtilis served as bacterial model organism in space. Due to the ability to form highly resistant endospores and complex biofilms, it was used to investigate the effects of unshielded space radiation as well as the limits of life in space. Within the International Space Station (ISS), fungal and bacterial biofilms already emerged as a burden that could harm the spacecraft due to material corrosion as well as the crew by causing infections. The ISS is a sensitive environment in which biofilm associated clogging or contaminating of life-support sy...

Here, we determined the relative importance of different transcriptional mechanisms in the genome-reduced bacterium Mycoplasma pneumoniae, by employing an array of experimental techniques under multiple genetic and environmental perturbations. Of the 143 genes tested (21% of the bacterium's annotated proteins), only 55% showed an altered phenotype, highlighting the robustness of biological systems. We identified nine transcription factors (TFs) and their targets, representing 43% of the genome, and 16 regulators that indirectly affect transcription. Only 20% of transcriptional regulation is mediated by canonical TFs when responding to perturbations. Using a Random Forest, we quantified the non-redundant contribution of different mechanisms such as supercoiling, metabolic control, RNA degradation, and chromosome topology to transcriptional changes. Model-predicted gene changes correlate well with experimental data in 95% of the tested perturbations, explaining up to 70% of the total variance when also considering noise. This analysis highlights the importance of considering non-TF-mediated regulation when engineering bacteria. ; The project was supported by funds from the Fundación Marcelino Botín and the Spanish Ministerio de Economía y Competitividad (BIO2007-61762). This project was financed by Instituto de Salud Carlos III and co-financed by Federación Española de Enfermedades Raras under grant agreement PI10/01702 and the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program, under grant agreements no 634942 (MycoSynVac) and 670216 (MYCOCHASSIS). We acknowledge support from the Spanish Ministry of Economy and Competitiveness to the EMBL partnership, Centro de Excelencia Severo Ochoa.