Research Summary:

Conjugation is probably the most common mechanism for genetic exchange in bacteria. Bacteria can transfer DNA by conjugation not only between different species, but also into higher organisms such as plants and yeast. Antibiotic-resistance genes on plasmids are generally disseminated by conjugation, and as a result, these genes have become so widespread that many antibiotics have now become useless therapeutically. In our lab, we are investigating at a molecular level the events that occur when DNA is passed from one cell to another by conjugation. We are determining the different steps in plasmid DNA processing that are required for transfer, and also how this DNA is recognized by the transfer machinery. Our long-term objective is to develop strategies for limiting the spread of antibiotic resistance by bacterial plasmids.