Date of Award
Master of Science (MS)
Luis R. Cruz-Vera
Drug resistance in microorganisms--Genetic aspects, Proteins, Escherichia coli
Drug-resistant infections pose serious medical threats, and causative resistance genes spread through plasmid conjugation. The TraT protein is a virulence factor encoded in drug-resistance F-plasmids. TraT itself provides protection from conjugation, serum complement, and bacteriophages, but the protective mechanism is unknown. To facilitate mechanism studies, I developed improved purification protocols for isolation of the soluble domain of F-plasmid TraT from Escherichia coli. Wild-type TraT and two variants were obtained. TraT domain forms several types of oligomers in vitro, also observed in full-length TraT. This oligomerization is stable without membrane attachment and in broad range of salt concentrations. Purified recombinant TraT was not found to interact with other proteins in conducted pull-down assays but it is able to protect E. coli cells from serum killing when added in trans. New purification protocols, protein variants, and oligomerization knowledge will be used to address knowledge gaps regarding structure and mechanisms of function.
Lott, Katelyn Ashley, "Characterization of TraT protein encoded in IncF resistance plasmids" (2022). Theses. 395.