Graduate Students Mini Symposium VII 2020

Program:

16:00 Hannah Jeckel, AG Drescher

An experimental setup to study spatiotemporal cell differentiation in bacterial swarms

The differentiation of genetically identical cells into multiple cell types with varying functions is a basic property of all complex life. As a model system for bacterial differentiation we study Bacillus subtilis swarms, which comprise of cells with different shapes and behaviors emerging in a spatiotemporal context. To investigate this process, we coupled an automated, adaptive microscopy routine scanning the swarm at single-cell level to a robotic setup capable of sampling cells from the swarm with high precision for RNA-sequencing. This approach, together with advanced data analysis techniques, will provide new insight into bacterial cell differentiation and multicellular dynamics.

16:30 Vitan Blagotinsek, AG Bange

Control of flagellation in the monotrichous bacterium Shewanella putrefaciens

The flagellum is a complex macromolecular structure found in many different bacterial species, where it is essential for motility and pathogenesis, where relevant. S. putrefaciens is a gram-negative bacterium with a single primary polar flagellum. The project involved an investigation of the flagellar numerical regulator FlhG and the type III secretion system substrate switch protein FlhB. FlhG has been found to bind both FliM, a C-ring component, and FlrA, a transcriptional regulator, through the same binding site. This depends on the dimerization state of FlhG as well as the presence of ATP (for FlrA binding). Additionally, with the help of X-ray crystallography, the structure of FlhB-C has been resolved at 2.1A resolution, identifying a novel proline-rich C-terminal motif with implications in flagellar biosynthesis.