Growth-dependent sensory bet-hedging enhances collective navigation.

Area of Science:

• Microbiology
• Systems Biology
• Biophysics

Background:

• Phenotypic heterogeneity in microbes presents a trade-off between individual survival and population coordination.
• Understanding this trade-off is complex due to multi-scale interactions from molecular to population levels.
• The Escherichia coli chemotaxis system exemplifies this, balancing individual exploration and collective resource exploitation.

Purpose of the Study:

• To investigate how microbes resolve the trade-off between individual adaptability and population coordination.
• To quantify phenotypic heterogeneity in Escherichia coli chemotaxis and its impact on collective behavior.
• To explore the role of growth rate and environmental variability in shaping sensory phenotypes and collective navigation.

Main Methods:

• Quantification of individual sensory and behavioral phenotypes in Escherichia coli.
• Measurement of key signaling protein abundance during growth in diverse environments.
• Assessment of the impact of phenotypic heterogeneity on population-scale collective migration.

Main Results:

• Growth rate was identified as a critical factor influencing both the mean and variance of sensory phenotypes.
• Sensory diversity was found to enhance, rather than impede, collective chemotactic navigation in uncertain environments.
• Phenotypic filtering by collective behavior was observed to achieve population coordination despite individual diversity.

Conclusions:

• Microbial phenotypic heterogeneity can serve as a bet-hedging strategy for collective navigation.
• Diversity in nutrient sensitivity is dynamically regulated: reduced for exploitation, increased for exploration.
• This strategy allows populations to balance focused resource acquisition with the exploration of new opportunities.