Study of the Interplay of Motility Mechanisms During Bacterial Swarming

Many bacteria use motility described as swarming to colonize surfaces in groups that allows them to survive external stresses including exposure to antibiotics. The main goal of this interdisciplinary project is to combine simulations using new three-dimensional multiscale  modeling environment and specifically designed experiments to study basic coordination events of bacterial swarming, which is essential to understanding how millions of bacteria function in real environments.  Specifically, the role of flexibility of cells, viscosity of extracellular polysaccharide, slime,  adhesivity and directional reversals in resolving collisions, increasing alignment and optimizing swarming rate during swarming of mutant strains (A*S') and ( AS*) and wild type (A^'S*) of M. xanthus swarming because of the ability to conduct  "experiments" in silico that are yet difficult (or impossible) to perform physically. A key aspect of this work will be to compare predictions obtained in silico with experimental observations. Study of the M. xanthus social interactions will provide an opportunity to gain fundamental insight into the biological response to how organisms discern, process, and respond to the chemical, physical, and biological cues present in their local environment.


Collaborators

  • Drs. Mark Alber, Zhiliang Xu, Danny Chen and Joshua Shrout (ACMS, Departments of Computer Science and Engineering, Civil Engineering and Geological Sciences, Notre Dame)
  • Dr. Igor Aronson (Argonne National Laboratory)
  • Dr. Dale Kaiser (Biochemistry, Stanford University)

 

Latest publications:

Cameron W. Harvey, Faruck Morcos, Christopher R. Sweet, Dale Kaiser, Santanu Chatterjee, Xiaomin Lu, Danny Chen and Mark Alber [2011], Study of elastic collisions of M. xanthus in swarms, Physical Biology 8: 026016.

Yilin Wu, Yi Jiang, A. Dale Kaiser, Mark Alber [2011], Self-organization in bacterial swarming: Lessons from Myxobacteria, Physical Biology 8(5):055003.


This image is a snapshot from a three-dimensional simulation of bacteria swarming. The biologically justified simulations are based on the Subcellular Elements Method where rod-shaped cells are represented as strings of nodes connected by springs. The goal of the model is to study how individual cell properties, such as flexibility and adhesivity, effect the collective motion of hundreds or even thousands of cells in a variety of experimentally observed structures.

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Click on the image below to start the cell simulation:

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