Date of Award


Document Type


Degree Name

Master of Science (MS)


Biological Sciences

Committee Chair

Tatyana Sysoeva

Committee Member

Luis R. Cruz-Vera

Committee Member

Joseph Ng


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.



To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.