Defense Date


Document Type


Degree Name

Master of Science



First Advisor

Dr. Gail E. Christie


Staphylococcus aureus pathogenicity island SaPI1 is a genomic element that is mobilized and transduced at high frequency by helper phage 80α. SaPI1 encodes a small terminase protein that belongs to the phage small terminase subunit family. The presence of SaPI1-encoded small terminase suggests that it plays a role in SaPI1-specific packaging into transducing particles by complexing with the 80α large terminase subunit and redirecting recognition to a pac site on SaPI1 DNA from 80α DNA. The effects of deleting the small terminase genes in SaPI1 and in a prophage copy of 80α are consistent with this hypothesis. Induction of the 80α small terminase deletion mutant produces wild type levels of SaPI1 transducing particles, demonstrating that SaPI1 small terminase can replace that of 80a in SaPI1 packaging. Southern blot analysis of virion DNAs isolated from the deletion mutants confirms that SaPI1 redirects packaging of its DNA into SaPI1-sized capsids.


© The Author

Is Part Of

VCU University Archives

Is Part Of

VCU Theses and Dissertations

Date of Submission

June 2008

Included in

Biology Commons