Presenter: Shirley Obioha
Phone: X6060
Email: sobioh60@stlawu.edu
Advisor: Carol Budd
Presentation format: Poster
 

“Transformation is the alteration of a bacterial cell’s genotype by the uptake of naked, foreign DNA from the surrounding environment” (Campbell, 1999). In our experiment we chose to use the transformation of plasmids conferring resistance to ampicillin to ampicillin- sensitive Escherichia coli. Our hypothesis was that the gene coding for ampicillin resistance was carried on the plasmids of the bacterial isolate and therefore transforming E. coli results in cells that are resistant to ampicillin through transformation of the plasmids.  The plasmids were isolated from bacteria obtained from river water cultured in Terrific broth medium.  Our results showed that transforming E. coli with plasmids was unsuccessful, but when transformed with fragments of chromosomal DNA containing the AmpR gene it was successful, therefore we rejected our hypothesis.  The bacterial isolates were also tested for other antibiotic resistance.  The bacterial isolates were only resistant to penicillin G, Triple Sulfa, and Bacitracin.  The isolated bacteria from the river water had a higher antibiotic sensitivity to Streptomycin.  The measured zone of inhibition for Streptomycin was 18 mm. There was high sensitivity to Carbenicillin, and Erythromycin. There were no zones of inhibition with the Triple Sulfa, Penicillin and Bacitracin. This experiment was under the supervision of Dr. Michael H. Temkin, Assistant Professor in biology. This experiment was also done with the help of Roy Lee my biology lab partner.