Cellular responsiveness as a predictive indicator for population collapse and autonomous control in continuous cultures of Pseudomonas putida.

Cellular responsiveness in Pseudomonas putida KT2440 declines with benzoate exposure, predicting population collapse at critical thresholds and enabling autonomous bioprocess control.

• Why it matters: Understanding how microbial populations adapt or fail under environmental stress is vital for optimizing biotechnological applications and ensuring process stability on challenging substrates.
• What they did: Using fluorescent biosensors and automated flow cytometry in the Segregostat platform, the study monitored cellular responses to benzoate, revealing a concentration-dependent suppression of gene circuit activation linked to fitness loss.
• The result: A resource competition model explained responsiveness decline, and a feedback-controlled bioreactor system leveraged this indicator to autonomously regulate substrate feeding, maintaining stable culture operation.