Reaction-diffusion model for pattern formation in E. coli swarming colonies with slime

Area of Science:

• Microbiology
• Biophysics
• Mathematical Biology

Background:

• Bacterial swarming involves collective cell migration on surfaces.
• Colonial patterns emerge from complex interactions between bacterial cells and their environment.
• Escherichia coli (E. coli) MG1655 is a model organism for studying bacterial behavior.

Purpose of the Study:

• To describe a novel experimental colonial pattern in E. coli MG1655 swarming.
• To develop and validate a reaction-diffusion model for E. coli swarming patterns.
• To understand the role of slime production and cell density in bacterial colonization.

Main Methods:

• Experimental observation of E. coli MG1655 swarming on semisolid agar.
• Development of a reaction-diffusion model incorporating slime generation, cell differentiation, and motility.
• Simulation and analysis of the model to reproduce experimental patterns and predict transitions.

Main Results:

• A new experimental colonial pattern and pattern transition were observed in E. coli MG1655.
• The reaction-diffusion model successfully reproduced the observed patterns.
• The model predicted changes in colonial patterns when bacterial collective motility was limited.
• Rapid surface colonization by E. coli MG1655 was attributed to fluid production and increased motile cell density.

Conclusions:

• E. coli MG1655 exhibits rapid surface colonization with a low branching rate due to fluid production and increased motile cell density.
• The developed reaction-diffusion model accurately describes E. coli swarming patterns and motility.
• Slime generation significantly influences bacterial differentiation and motion, driving pattern formation.