@misc{AlirezaeizanjaniGrossmannPfeiferetal.2020, author = {Alirezaeizanjani, Zahra and Großmann, Robert and Pfeifer, Veronika and Hintsche, Marius and Beta, Carsten}, title = {Chemotaxis strategies of bacteria with multiple run modes}, series = {Zweitver{\"o}ffentlichungen der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Zweitver{\"o}ffentlichungen der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {22}, issn = {1866-8372}, doi = {10.25932/publishup-51909}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-519098}, pages = {10}, year = {2020}, abstract = {Bacterial chemotaxis-a fundamental example of directional navigation in the living world-is key to many biological processes, including the spreading of bacterial infections. Many bacterial species were recently reported to exhibit several distinct swimming modes-the flagella may, for example, push the cell body or wrap around it. How do the different run modes shape the chemotaxis strategy of a multimode swimmer? Here, we investigate chemotactic motion of the soil bacterium Pseudomonas putida as a model organism. By simultaneously tracking the position of the cell body and the configuration of its flagella, we demonstrate that individual run modes show different chemotactic responses in nutrition gradients and, thus, constitute distinct behavioral states. On the basis of an active particle model, we demonstrate that switching between multiple run states that differ in their speed and responsiveness provides the basis for robust and efficient chemotaxis in complex natural habitats.}, language = {en} } @article{AlirezaeizanjaniGrossmannPfeiferetal.2020, author = {Alirezaeizanjani, Zahra and Großmann, Robert and Pfeifer, Veronika and Hintsche, Marius and Beta, Carsten}, title = {Chemotaxis strategies of bacteria with multiple run modes}, series = {Science advances}, volume = {6}, journal = {Science advances}, number = {22}, publisher = {American Association for the Advancement of Science}, address = {Washington}, issn = {2375-2548}, doi = {10.1126/sciadv.aaz6153}, pages = {8}, year = {2020}, abstract = {Bacterial chemotaxis-a fundamental example of directional navigation in the living world-is key to many biological processes, including the spreading of bacterial infections. Many bacterial species were recently reported to exhibit several distinct swimming modes-the flagella may, for example, push the cell body or wrap around it. How do the different run modes shape the chemotaxis strategy of a multimode swimmer? Here, we investigate chemotactic motion of the soil bacterium Pseudomonas putida as a model organism. By simultaneously tracking the position of the cell body and the configuration of its flagella, we demonstrate that individual run modes show different chemotactic responses in nutrition gradients and, thus, constitute distinct behavioral states. On the basis of an active particle model, we demonstrate that switching between multiple run states that differ in their speed and responsiveness provides the basis for robust and efficient chemotaxis in complex natural habitats.}, language = {en} } @misc{BetaGovYochelis2020, author = {Beta, Carsten and Gov, Nir S. and Yochelis, Arik}, title = {Why a Large-Scale Mode Can Be Essential for Understanding Intracellular Actin Waves}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {967}, issn = {1866-8372}, doi = {10.25932/publishup-47358}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-473588}, pages = {20}, year = {2020}, abstract = {During the last decade, intracellular actin waves have attracted much attention due to their essential role in various cellular functions, ranging from motility to cytokinesis. Experimental methods have advanced significantly and can capture the dynamics of actin waves over a large range of spatio-temporal scales. However, the corresponding coarse-grained theory mostly avoids the full complexity of this multi-scale phenomenon. In this perspective, we focus on a minimal continuum model of activator-inhibitor type and highlight the qualitative role of mass conservation, which is typically overlooked. Specifically, our interest is to connect between the mathematical mechanisms of pattern formation in the presence of a large-scale mode, due to mass conservation, and distinct behaviors of actin waves.}, language = {en} } @article{BetaGovYochelis2020, author = {Beta, Carsten and Gov, Nir S. and Yochelis, Arik}, title = {Why a Large-Scale Mode Can Be Essential for Understanding Intracellular Actin Waves}, series = {Cells}, volume = {9}, journal = {Cells}, number = {6}, publisher = {MDPI}, address = {Basel}, issn = {2073-4409}, doi = {10.3390/cells9061533}, pages = {18}, year = {2020}, abstract = {During the last decade, intracellular actin waves have attracted much attention due to their essential role in various cellular functions, ranging from motility to cytokinesis. Experimental methods have advanced significantly and can capture the dynamics of actin waves over a large range of spatio-temporal scales. However, the corresponding coarse-grained theory mostly avoids the full complexity of this multi-scale phenomenon. In this perspective, we focus on a minimal continuum model of activator-inhibitor type and highlight the qualitative role of mass conservation, which is typically overlooked. Specifically, our interest is to connect between the mathematical mechanisms of pattern formation in the presence of a large-scale mode, due to mass conservation, and distinct behaviors of actin waves.}, language = {en} } @article{GomezNavaGrossmannHintscheetal.2020, author = {G{\´o}mez-Nava, Luis and Grossmann, Robert and Hintsche, Marius and Beta, Carsten and Peruani, Fernando}, title = {A novel approach to chemotaxis}, series = {epl : a letters journal exploring the frontiers of physics}, volume = {130}, journal = {epl : a letters journal exploring the frontiers of physics}, number = {6}, publisher = {IOP Publ. Ltd.}, address = {Bristol}, issn = {0295-5075}, doi = {10.1209/0295-5075/130/68002}, pages = {7}, year = {2020}, abstract = {Motivated by the observation of non-exponential run-time distributions of bacterial swimmers, we propose a minimal phenomenological model for taxis of active particles whose motion is controlled by an internal clock. The ticking of the clock depends on an external concentration field, e.g., a chemical substance. We demonstrate that these particles can detect concentration gradients and respond to them by moving up- or down-gradient depending on the clock design, albeit measurements of these fields are purely local in space and instantaneous in time. Altogether, our results open a new route in the study of directional navigation: we show that the use of a clock to control motility actions represents a generic and versatile toolbox to engineer behavioral responses to external cues, such as light, chemical, or temperature gradients.}, language = {en} } @article{YochelisBetaGov2020, author = {Yochelis, Arik and Beta, Carsten and Gov, Nir S.}, title = {Excitable solitons}, series = {Physical review : E, Statistical, nonlinear and soft matter physics}, volume = {101}, journal = {Physical review : E, Statistical, nonlinear and soft matter physics}, number = {2}, publisher = {American Physical Society}, address = {Melville, NY}, issn = {2470-0045}, doi = {10.1103/PhysRevE.101.022213}, pages = {6}, year = {2020}, abstract = {Excitable pulses are among the most widespread dynamical patterns that occur in many different systems, ranging from biological cells to chemical reactions and ecological populations. Traditionally, the mutual annihilation of two colliding pulses is regarded as their prototypical signature. Here we show that colliding excitable pulses may exhibit solitonlike crossover and pulse nucleation if the system obeys a mass conservation constraint. In contrast to previous observations in systems without mass conservation, these alternative collision scenarios are robustly observed over a wide range of parameters. We demonstrate our findings using a model of intracellular actin waves since, on time scales of wave propagations over the cell scale, cells obey conservation of actin monomers. The results provide a key concept to understand the ubiquitous occurrence of actin waves in cells, suggesting why they are so common, and why their dynamics is robust and long-lived.}, language = {en} }