Genetic Transformation of the Model Quorum Sensing Bacterium Vibrio campbellii by Electroporation

The marine bacterium Vibrio campbellii has been a model system for the study of bacterial quorum sensing and is increasingly recognized as a formidable aquatic animal pathogen. While genetically tractable, the study of this species in basic and applied research still relies upon laborious and time-consuming conjugation methods for plasmid DNA transformation.

In this study, we developed an electroporation protocol using the most studied strain of this species, V. campbellii ATCC BAA-1116. An electroporation efficiency of up to 3 × 10⁴ CFU/μg DNA was demonstrated using derived parameters (10 kV/cm, 400 Ω, 25 μF), which took cell growth phase at harvest, plasmid DNA amount, and recovery conditions into account. The electroporation protocol was tested using several different plasmids and with additional strains of V. campbellii and sister species V. harveyi.

Interestingly, of the eight other V. campbellii strains tested, only three others, which also happened to be the three most recent environmental isolates with the fewest number of laboratory passages, were amenable to electroporation-mediated transformation.

This electroporation protocol expands the tool set for studying V. campbellii and provides interesting insights into DNA transformation and uptake in this and related bacterial species.