Late-Stages in Bacterial Conjugation: The role of F plasmid TraD protein
The main focus of these experiments is the role of TraD in bacterial conjugation. Conjugation is a process through which a donor cell transfers DNA to a recipient cell. The major steps in bacterial conjugation mediated by the F plasmid Tra (transfer) proteins are the formation of a pilus, contact between the pilus and recipient cell, transfer of DNA, retraction of the pilus into the donor cell, nicking and unwinding of plasmid DNA. Although its precise function in conjugation is not currently known, prior studies have shown that TraD is required for the DNA transfer step. TraD is also required for lytic infection of various F-specific RNA bacteriophages including R17 and MS2 but not Qb or the filamentous DNA phages. The student will conduct experiments to explore the function of TraD in conjugation and in phage infection, other Tra proteins with which TraD may interact, and TraD's relation to the DNA processing machinery. In these studies, the student will utilize phage infection assays, mating assays, cloning techniques and protein expression and detection techniques. She will make a TraD-GFP fusion construct that will be active in conjugation as well as visible under a microscope. She will also employ existing mutants in conjugation and infection processes and note the changes and effects on the system.
