Mathematical Biology-Swarms of Bacteria

Myxobacteria (Myxococcus xanthus) change their life cycle according to food availability in their environment. In an ideal condition, myxobacteria grow as swarms that spread away from the center of a colony to search for nutrients from the medium and oxygen from above. However, when nutrients are depleted,myxobacteria undergo a phase transition in which they stop growing individually, but instead they merge and build a complex structure, called the fruiting body. The stage of fruiting body development is thus initiated by starvation and built by cell movements and interactions. The substages of fruiting body development that are observed in the experiments consist of the formation of traffic jams and initial aggregates, streaming, formation of three-dimensional hemispherical mounds, formation of toroidal mounds, and sporulation within the fruiting body.