Bacterial Crowd Control
Colonies of bacterial cells can display complex collective dynamics, frequently culminating in the formation of biofilms and other ordered super-structures, particularly in response to hostile environmental conditions. Recent studies suggest that to cope with local environmental challenges, bacterial cells can actively seek out small chambers or cavities and assemble there, engaging in quorum sensing behavior. However, bacteria in cavities may suffer from poor nutrient supply or waste removal, or disorganized expansion leading to blockage of cell escape.
These authors observed Escherichia coli in a novel microfluidic device which allows direct observation of the growth and development of cell colonies in microchambers of different shapes and sizes through multiple generations. Combining these experiments with computational analysis of colony growth and expansion, they showed that within chambers of distinct shapes and sizes allowing continuous cell escape, bacterial colonies gradually self-organize. The directions of orientation of cells, their growth, and collective motion are mutually correlated and dictated by the chamber walls and locations of chamber exits. The ultimate highly organized steady state is conducive to a more-organized escape of cells from the chambers and increased access of nutrients into and evacuation of waste out of the colonies. Using a computational model, they suggest that the lengths of the cells might be optimized to maximize self-organization while minimizing the potential for stampede-like exit blockage.
The type of self-organization described in this paper may be crucial for the early stage of the organization of high-density bacterial colonies populating small, physically confined growth niches. It suggests that this phenomenon can play a critical role in bacterial biofilm initiation and development of other complex multicellular bacterial super-structures, including those implicated in infectious diseases.
Tags: Bacteria, Biofilms, Biology, Microbiology, Science
Well, I am not very interested in whether certain biofilm can be critical for ceratain infection.What is interesting for me is that very exciting and unique organization and comunication among bacteria, which can be achieved even by different species.Quorum sensing is the way of communication among bacteria, using specific chemical compounds, which can be the same among Gram (-) and Gram (+).