Center for Complex and Nonlinear Science

We develop the off-lattice model to simulate the life cycle of Myxococcus xanthus. When the food is abundant, they grow as swarms that spread away from the colony. In this stage, their movement and coordination are determined by their A-motility and S-motility engines. However, when they are in starvation, C-signaling between cells takes place and changes their cell-cell coordination. This allows them to form an aggregate which eventually develops into a fruiting body. Cells inside the fruiting body differentiate into round nonmotile spores which are resistant to adverse condition. In this paper, the Dynamic Energy Budget model is used as a trigger mechanism for cell growth and cell division, and then for switching from the swarming stage to the stage of fruiting body formation. Moreover, the logistic equation is implemented to count the number of C-signal molecules on each cell surface, which is then used as a switch for transitions between the stages of fruiting body formation.