BACTERIAL POPULATION AUTOWAVE PATTERNS - SPONTANEOUS SYMMETRY BURSTING

Bacteria are known to form autowave patterns (population waves) like t hose formed by propagating nerve impulses, phase transitions, concentr ation waves in the Belousov-Zhabotinsky reaction, etc. The formation o f bacterial waves is due to the ability of bacteria to drift (through chemotaxis) into the regions with higher attractant concentration. As a result, in contrast to other types of autowaves, bacterial populatio n waves have not only a diffusion component of a bacterial flow but a chemotaxis flow as well. We present the experimental results of the st udy of spontaneous symmetry loss of bacterial autowave patterns. We sh ow that this phenomenon can be simulated with a simple cellular automa ta model, and symmetry bursting depends on the parameters characterizi ng chemotactic sensitivity and motility of the cells forming the popul ation wave. In the experiments in vivo we show that the distortion of a bacterial wave shape can be initiated by bacterial density fluctuati ons in the parent population that the bacterial waves flake off from.