Standardized Quorum Sensing Tools for Gram-Negative Bacteria.

Engineering synthetic consortia to perform distributed functions requires robust quorum sensing (QS) systems to facilitate communication between cells. However, the current QS toolbox lacks standardized implementations, which are particularly valuable for use in bacteria beyond the model species Escherichia coli. We developed a set of three QS systems encompassing both sender and receiver modules, constructed using backbones from the SEVA (Standard European Vector Architecture) plasmid collection. This increases versatility, allowing plasmid features like the origin of replication or antibiotic marker to be easily swapped. The systems were characterized using the synthetic biology chassis Pseudomonas putida. We first tested individual modules, then combined sender and receiver modules in the same host, and finally assessed the performance across separate cells to evaluate consortia dynamics. Alongside the QS set, we provide mathematical models and rate parameters to support the design efforts. Together, these tools advance the engineering of robust and predictable multicellular functions.