Spatial organization in nano-sculptured bacteria, a tale of shape, scale, patterns, and genomes

Spatial organization in nano-sculptured bacteria, a tale of shape, scale, patterns, and genomes

Wu, F.

Dekker, C. (promotor)

Applied Sciences

Bionanoscience

2015-10-27

One of the most basic features that pervade biology is the existence of boundaries that separate living cells from their outer environments. Molecules responsible for the internal organization of a living cell must adapt to its boundaries, as the cell grows, divides, and changes in shape and size. In this thesis, we aim to understand how intracellular protein networks and chromosomes perceive boundary geometries and in turn organize themselves to guide proper distribution of material during cell growth and division. To manipulate cell boundaries, we use nanofabricate microchambers to guide living bacterial cells to grow into defined shapes such as circles, triangles, squares and rectangles in a large range of sizes. Quantitative studies using this novel ‘cell-sculpting’ technique reveal that Min proteins form oscillation patterns that sense the symmetry axes of the cell shapes and scale their concentration gradient in adaptation to cell sizes, thus ensuring Escherichia coli bacteria to place their division machineries right at the cell center. Chromosomes in E. coli are found to compact and rearrange under the constraints of cell boundaries and they migrate during cell growth through their interactions with cell membrane. These organizational patterns, together with a versatile formation of the FtsZ cytoskeletal filaments, lead to a remarkable ability of E. coli to robustly and accurately divide in diverse shapes.

cell shape
pattern formation
chromosome organization
bacterial cell division
nanotechnology
microfluidics
antibiotics
fluorescent proteins
quantitative biology

https://doi.org/10.4233/uuid:45a274ba-1811-4efd-b329-06e056a31395

2016-10-27

978-90-8593-228-4

Institutional Repository

doctoral thesis

(c) 2015 Wu, F.