North Carolina State University Undergraduate Symposium





2012- 21st Annual NC State Undergraduate Research Symposium

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Session Time : 4/10/12 12:15 PM - 4/10/12 1:30 PM
Content Area : Microbiology

Poster Appointment: , -  
Student Presenters :       
Tayla W Cunningham Human Biology
Mentors and/or Co-Authors :
Deborah Threadgill Microbiology
Erin Harrell Microbiology
Abstract Title : The mutagenenesis of the rpsL gene of Campylobacter rectus (ATCC 33238) to confer streptomycin resistance
Abstract :
Campylobacter rectus (C.rectus) is a gram-negative, anaerobic rod and has been shown to be associated with adult periodontitis; a chronic inflammatory disease in which destruction of the supporting oral structures (i.e. the gums) can lead to tooth loss. Some of the possible virulence factors of this bacterium are its method of motility (flagella) and the possible production of cytotoxins. Additionally, the S-layer surrounding the outer membrane of this bacterium can induce cytokine release in host cells. Though C. rectus is said to be an etiological agent of periodontal disease, it is currently not classified as a pathogenic bacteria and very little is known about its virulence mechanisms. The genome of C.rectus contains some genes that may be involved in natural transformation. This process allows a bacterium to be highly flexible and acquire additional virulence genes. Helicobacter pylori (H.pylori) and C. rectus have a homologous gene, rpsL. In H. pylori, when a specific point mutation is carried out in this gene, and that extracellular DNA is taken up through  natural transformation, it confers streptomycin resistance. By inducing this same point mutation in the rpsL gene of C.rectus (33238), it is possible to demonstrate the natural competency of C.rectus through acquisition of streptomycin resistance. I amplified, cloned, and successfully carried out a 129 A to G point mutation in the rpsL gene using site-directed mutagenesis. Currently, we are attempting to naturally transform the mutated rpsL gene back into the genome of C.rectus (33238), but have been unsuccessful, thus far.