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arXiv · 1802.01156

Dynamic density shaping of light driven bacteria

Giacomo Frangipane·Dario Dell'Arciprete·Serena Petracchini·Claudio Maggi·Filippo Saglimbeni·Silvio Bianchi·Gaszton Vizsnyiczai·Maria Lina Bernardini·Roberto Di Leonardo
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Abstract

Many motile microorganisms react to environmental light cues with a variety of motility responses guiding cells towards better conditions for survival and growth. The use of spatial light modulators could help to elucidate the mechanisms of photo-movements while, at the same time, providing an efficient strategy to achieve spatial and temporal control of cell concentration. Here we demonstrate that millions of bacteria, genetically modified to swim smoothly with a light controllable speed, can be arranged into complex and reconfigurable density patterns using a digital light projector. We show that a homogeneous sea of freely swimming bacteria can be made to morph between complex shapes. We model non-local effects arising from memory in light response and show how these can be mitigated by a feedback control strategy resulting in the detailed reproduction of grayscale density images.

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Giacomo Frangipane, Dario Dell'Arciprete, Serena Petracchini, Claudio Maggi, Filippo Saglimbeni, Silvio Bianchi, Gaszton Vizsnyiczai, Maria Lina Bernardini, Roberto Di Leonardo. 2018-07-16. Dynamic density shaping of light driven bacteria. https://doi.org/10.7554/elife.36608

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