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Date of Award


Document Type

Restricted Thesis: Campus only access

Degree Name

Bachelor of Science



First Advisor

Dr. Bradley Goodner


Agrobacterium tumefaciens is a Gram negative soil bacterium, which is found worldwide, and is a causative agent involved in crown gall disease on many dicotyledonous plants. The virulence mechanism of this pathogen is unique in that AgrobacteriumDNA is transferred to infected plant cells, thereby allowing the disease to remain even after the bacterium is removed. In addition, Agrobacteriumhas been found to be an opportunistic animal pathogen. Like most bacteria, Agrobacterium was originally assumed to have a single, circular chromosome. In 1993, a French lab obtained physical data, from gel electrophoresis of intact chromosomal DNA, that strongly suggested that A. tumefacienscontains both a circular and a linear chromosome. Our lab first became interested in the Agrobacterium tumefaciens genome because of its unique combination of topologies, and thus repeated and confirmed the experiments of the French group: A. tumefaciensstrain C58 contains a 3Mb circular chromosome, a 2.1 Mb linear chromosome, the 450 kb cryptic plasmid, and the 200 kb Ti plasmid. A project was initiated three years ago to dispel the differences between the physical map and previous genetic maps. This resulted in the production of a combined genetic/physical map of the two chromosomes.