Plasmid conjugation-based logic gates

Abstract

Conjugation is a natural communication mechanism among bacteria that relies in plasmids as vehicles. The conjugation hardware is highly specific and robust, allowing the independent transmission of different conjugative plasmids without interference. We constructed an E. coli derivative containing a chromosomally-inserted conjugative W-wire and engineered a recombinant plasmid series able to compute the basic logic gates YES, AND, OR. The computing strain was used as a donor in mating experiments and a reporter strain able to trigger the production of a fluorescent protein from the reporter plasmid was used as recipient. The functionality and specificity of these circuits constitute a proof of principle that cell-cell communication mediated by conjugative plasmids could be implemented as a new tool in Synthetic Biology to distribute genetic circuits in bacterial populations.