Using experimental data and numerical models to compute the dynamics of Pseudomonas aeruginosa

The Trinity-Centre Collaboration uses dynamically similar table-top experiments to calibrate the Method of Images for Regularized Stokeslets (MIRS) for use as a noninvasive probe of bacterial swimming dynamics. We study the motile bacterium Pseudomonas aeruginosa, which consists of a rod-shaped body and a single polar flagellum. A molecular motor and a helical flagellar filament propel the cell through its low Reynolds number environment, in which nearby boundaries significantly increase fluid forces and torques. Bacterial trajectories are measured using TIRF microscopy, and our new tracking scheme yields both orientation and boundary distance. The trajectories are inputs into the MIRS from which forces and torques are computed to better understand how P. aeruginosa and other bacteria swim using a helical flagellum. See the accompanying talks by Kate Brown and Hoa Nguyen to see how the experiments are conducted and the MIRS is calibrated.