Variable cell morphology approach for individual-based modeling of microbial communities.

Area of Science:

• Microbial Ecology
• Biophysics
• Computational Biology

Background:

• Biofilm and microbial aggregate structure formation is complex.
• Understanding the mechanical properties governing microbial community architecture is crucial.

Purpose of the Study:

• To develop and apply an individual-based, mass-spring modeling framework to investigate how cell properties influence biofilm and microbial aggregate structure.
• To explore the role of mechanical interactions and cell-cell links in microbial colony formation.

Main Methods:

• Utilized a Lagrangian modeling approach with a mass-spring framework.
• Incorporated variable cell morphology using particles connected by springs.
• Modeled deformable intracellular, intercellular, and cell-substratum links.

Main Results:

• Modeled colony formation of rod-shaped bacteria (bacilli), showing cell-substratum links promote mounds and filial links affect roundness.
• Simulated mixed-culture activated sludge, demonstrating how cell-cell links, morphology, and growth kinetics can cause filamentous proliferation and sludge bulking.
• Extended the model to advanced morphologies like filament branching.

Conclusions:

• Mechanical interactions are vital in microbial communities, influencing biofilm architecture.
• The developed modeling framework is a powerful tool for understanding how fundamental mechanisms dictate microbial colony architectures.
• This approach can identify causes of detrimental phenomena like sludge bulking.