Perception and regulatory principles of microbial growth control

Area of Science:

• Microbial Physiology
• Metabolic Engineering
• Evolutionary Biology

Background:

• Microbial growth rate is crucial for survival in competitive environments.
• Metabolic adaptation to nutrient availability is key for maximizing growth.
• Regulation of metabolic pathways differs significantly across microbial species.

Purpose of the Study:

• To investigate whether intracellular metabolic state perception enhances microbial growth compared to extracellular nutrient perception.
• To model and compare the competitive fitness of microbes employing different nutrient sensing strategies.

Main Methods:

• Development of a simplified dynamical computer model of a cellular metabolic network.
• Inference of metabolic regulation using an optimization approach.
• Simulation of a competing species experiment comparing intracellular vs. extracellular perception.

Main Results:

• Intracellular perception provides a growth advantage in environments with rapidly changing nutrient availability.
• Optimal regulation under intracellular perception prioritizes preferential nutrients, akin to catabolite repression.
• Metabolic pathways remain constitutively active, enabling immediate nutrient uptake when available.

Conclusions:

• Intracellular nutrient perception confers a significant fitness advantage in fluctuating environments.
• This strategy enhances microbial survival by outcompeting rivals through superior growth dynamics.
• The findings offer insights into microbial adaptation and evolutionary strategies.