A Minimal Stochastic Model of Microbial Ecological Dynamics in a Single-Species-Single-Resource Setting

Area of Science:

• Microbiology
• Theoretical Biology
• Biophysics

Background:

• Microbial dynamics result from complex interactions and environmental factors.
• Understanding microbial growth mechanisms, nutrient roles, and stochasticity remains challenging.

Purpose of the Study:

• To develop a minimal theoretical model clarifying the link between microbial resource consumption and growth.
• To investigate the influence of stochasticity on microbial population dynamics.

Main Methods:

• Analytical study of a stochastic model for a single microbial species consuming a single resource.
• Monte Carlo computer simulations to analyze microbial growth dynamics.

Main Results:

• Identification of three distinct microbial growth regimes based on resource uptake and division rates.
• Demonstration of stochasticity's significant impact on dynamics at low microbial or resource levels.
• Mechanistic interpretation of Monod growth kinetics, including the Monod constant and maximal growth rate.

Conclusions:

• The presented theoretical framework captures diverse microbial dynamic behaviors.
• Provides a clearer microscopic understanding of microbial growth mechanisms.
• Offers insights into the interplay between resource availability, growth rates, and stochastic effects in microbial systems.