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Cell shape is a pervasive feature which guides the orchestration of the subcellular organizations. By inoculating Escherichia coli cells with cell-wall-targeting agents in nanofabricated structures, we guide individual cells to adopt pre-defined shapes such as squares, circles, and triangles, with volumes ranging from 4 to 72 μm3. We use these sculptured bacteria to explore the shape-recognition mechanism and spatial plasticity of the MinCDE protein system, which is involved in positioning cell division machinery through MinD proteins that oscillate in time along the long axis of rod-shape E. coli. Surprisingly, Min proteins are able to sustain stable spatial oscillations in a broad spectrum of geometries, exhibiting remarkable plasticity. We observe multi-modal switches in dynamic Min patterns as the lateral dimensions increase from 2μm to 11μm in identical shapes. Our data reveal an intrinsic wavelength dictating the orientation of the Min oscillations, challenging various models that attribute the Min pattern formation to membrane curvature, binding-zone size, or long-axis recognition. Computational simulations show that this wavelength is a result of a MinD cytosolic transfer distance restricted by the rates of MinD corporative-binding and its sequestration by MinE.View Large Image | View Hi-Res Image | Download PowerPoint Slide |
