Collective Movement in Myxobacteria: Modeling and Experiments with Myxococcus xanthus

A remarkable example of how patterns of movement and organization in populations of bacterial cells emerge from individual level interactions is seen with Myxobacteria. How cells coordinate movement is fundamental to many important areas of study from development biology where cells must form patterns and differentiate with precise timing to topics like infectious diseases where bacterial cells can colonize surfaces and infect tissue. In this thesis, I will present a study on the biophysical mechanisms that drive pattern formation in both phases of the Myxococcus xanthus life cycle. In this study that combines experiments with computational modeling and simulation, I will present novel techniques for imaging the patterns of movement and cellular organization that reveal unique patterns of clustering. The experimental observations helped to inform the development of a cell-based biophysical model that account for the adhesive forces between cells and the elastic properties of the cells. Simulations with this model were used to study how the physical and behavioral properties impact the ability of cells to form and move as organized clusters of cells. My findings provide new insight into the three-dimensional structure of myxo fruiting bodies as well as the demonstrate the importance of both physical and behavioral properties in the role of multi-cellular coordination.