Bacterial species interactions significantly shape growth and behavior in communities, determining the emergence of community functions. Typically, these interactions are studied through bulk population measurements, overlooking the role of cell-to-cell variability and spatial context. This study uses real-time surface growth measurements of thousands of sparsely positioned microcolonies to investigate interactions and kinetic variations in monocultures and cocultures of and under substrate competition (succinate) or substrate independence (d-mannitol and putrescine).
View Article and Find Full Text PDFConjugative transfer of the integrative and conjugative element ICE in requires development of a transfer competence state in stationary phase, which arises only in 3-5% of individual cells. The mechanisms controlling this bistable switch between non-active and transfer competent cells have long remained enigmatic. Using a variety of genetic tools and epistasis experiments in , we uncovered an 'upstream' cascade of three consecutive transcription factor-nodes, which controls transfer competence initiation.
View Article and Find Full Text PDFWhole-cell bacterial bioreporters are proposed as alternatives to chemical analysis of, for example, pollutants in environmental compartments. Commonly based on reporter gene induction, bioreporters produce a detectable signal within 30 min to a few hours after exposure to the chemical target, which is impractical for applications aiming at a fast response. In an attempt to attain faster readout but maintain flexibility of chemical targeting, we explored the concept for quantitative chemical sensing by bacterial chemotaxis.
View Article and Find Full Text PDFThe pathogenesis and pathology of African animal trypanosomosis (AAT) in Baoulé, N'Dama/Baoulé-cross-bred and Zebu cattle was studied from 1987 to 1991 in a series of experiments conducted under natural and artificial conditions of challenge at the Centre de Recherches sur les Trypanosomoses Animales (CRTA) in Burkina Faso. This first paper reports on the clinical performance of 64 Baoulé, 10 N'Dama/Baoulé-cross-bred and 20 Zebu cattle, which were transferred to the pastoral zone of Satiri, 50 km northeast of Bobo-Dioulasso, a zone infested with Glossina palpalis gambiensis, G. morsitans submorsitans and G.
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