The goal of the proposed study is to investigate how bacteria interact in a non-aquaeous fluid environment, which is often found in biological fluids. Findings from this work will be applicable to a general set of bacteria that swim using the same basic mechanics and could explain why bacteria in aqueous environments are uni-flagellar while other bacteria are multi-flagellar. Results of this work are important, since microscopic swimmers like bacteria are most often found in body fluids and liquids that are complex and non-Newtonian. There is a need for both data and models in this area, in order to better understand the spreading of decease and ways to stop it. There is also involvement of K-12 students in the outreach part of the project.
The focus of the proposal is on explaining flagellar swimming in viscoelastic media at a fundamental level. In particular, this experimental study will focus on uni-flagellated swimmers and how their motion is different than multi flagellated in viscoelastic media. The approach is to use single flagellum model bacteria in different viscoelastic solutions. The experimental measurements will include quantitative observations of swimming trajectories, speed, and cell body kinematics using optical microscopy techniques. In addition, rheological models will be generated to interpret the experimental results.