In this work I present a novel conformation of the Bacillus stearothermophilus UvrA (BstUvrA) protein and biochemical data to support its validity. The 2.1 A crystal structure is of a truncation of the protein lacking the UvrB-binding domain and the Insertion domain but retaining the two nucleotide binding sites. It captures a conformation in which the proximal binding site is vacant and its signature domain, signature domain II, has rotated away from the nucleotide binding site. The distal site is occupied by ADP and assumes a similar fold to that observed in the full-length BstUvrA structure. Much remains unknown about the mechanism by which UvrA deposits UvrB onto a DNA lesion to create the pre-incision complex. The rearrangement of the proximal site may represent the "disengaged" conformation of UvrA, as it leaves behind the UvrB-DNA pre-incision complex loaded at the site of DNA damage.
In addition, I present work characterizing a bacterial gene product that was identified as a joint primase-MCM helicase. The novelty of this protein is that MCMs behave as the eukaryotic replicative helicase, a process which most bacteria perform with the protein DnaB. While I was able to find evidence of MCM helicase activity by the gene product, no primase activity was observed.
|School Location:||United States -- Massachusetts|
|Source:||DAI-B 72/09, Dissertation Abstracts International|
|Keywords:||DNA damage, MCM helicase, Nucleotide excision repair|
Copyright in each Dissertation and Thesis is retained by the author. All Rights Reserved
The supplemental file or files you are about to download were provided to ProQuest by the author as part of a
dissertation or thesis. The supplemental files are provided "AS IS" without warranty. ProQuest is not responsible for the
content, format or impact on the supplemental file(s) on our system. in some cases, the file type may be unknown or
may be a .exe file. We recommend caution as you open such files.
Copyright of the original materials contained in the supplemental file is retained by the author and your access to the
supplemental files is subject to the ProQuest Terms and Conditions of use.
Depending on the size of the file(s) you are downloading, the system may take some time to download them. Please be