Bacterial sugar utilization gives rise to distinct single-cell behaviours

Area of Science:

• Microbiology
• Systems Biology
• Synthetic Biology

Background:

• Inducible utilization pathways are key microbial strategies for environmental sugar uptake.
• Understanding single-cell responses of these pathways remains limited.

Purpose of the Study:

• To investigate the natural single-cell behaviors of inducible sugar utilization pathways in Escherichia coli.
• To elucidate the mechanisms governing diverse pathway responses.

Main Methods:

• Single-cell analyses of representative pathways in Escherichia coli.
• Mathematical modeling of pathway dynamics.
• Probing genetically modified pathways.

Main Results:

• Observed diverse single-cell behaviors: uniform, 'all-or-none', and complex responses.
• Demonstrated that inducible transport and catabolism generate these behaviors.
• Showed sugar catabolism is crucial for tunable induction and memory; its disruption led to constitutive induction.

Conclusions:

• The simple framework of inducible transport and catabolism exhibits remarkable flexibility in generating diverse cellular responses.
• Findings have implications for microbial environmental adaptation and engineering of synthetic pathways for applications in titratable expression and metabolic engineering.