Exploring the optimality of various bacterial motility strategies : a stochastic hybrid systems approach

While many species of bacteria are motile, they use various random strategies to determine where to swim. This chemotaxis allow bacterial populations to distribute themselves in accordance to distributions of nutrients found within an environment. We extend past work describing a chemotactic E. coli cell as an ergodic, stochastic hybrid system and use experimental data on bacterial motion in microfluidic environments to model other species of bacteria. Our focus is on understanding the differences between the run-and-tumble strategy of E. coli and the more complicated run-reverse-flick strategy of the marine bacterium Vibrio alginolyticus. We use stochastic stability theory to analyze the chemotaxis models in terms of their stationary distributions and also derive a diffusion approximation of the system that provides further insight into the performance of various strategies. By comparing general chemotactic strategies, we hypothesize why various strategies may be evolutionarily advantageous for particular environments. These results also provide intuition for designing minimalistic multi-agent robotic systems that can be used for various environmental monitoring and source-seeking tasks.

Department dc:contributor.department

Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2013

Author dc:creator

• Norris, Noele Rosalie

Advisor dc:contributor.advisor

• Emilio Frazzoli.

• Electrical Engineering and Computer Science.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/84722

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/84722