Date of Award


Degree Type


Degree Name

Master of Science




Dr. David Haniford

Second Advisor

Dr. David Edgell

Third Advisor

Dr. Chris Brandl


Transposons are mobile DNA segments. The transposition of transposable elements can have important effects on genome structure and function. In this thesis, we demonstrate that a histone-like nucleoid structuring protein (H-NS), acts as an anti-channeling factor to limit self-destructive intramolecular transposition events and allows for the dissemination of the bacterial transposon TnlO in vitro. Evidence that H-NS competes with IHF for binding to the TnlO transpososome to block channelling, and that this event is relatively insensitive to the level of DNA supercoiling present in the Tnl0-containing substrate plasmid, are presented. We also demonstrate that H-NS rescues the transposition defect observed in a R182A transposase mutant reaction pathway by unfolding the transpososome to promote transposon excision and strand transfer. For the first time, we have provided the strongest evidence to date that in vivo H-NS promotes TnlO transposition by acting directly on the transpososome.



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.