Studying the Genetic Growth of Porphyromonas Gingivalis

I have been studying Porphyromonas gingivalis. P. gingivalis is an anaerobic gram negative bacterium found in the mouth below the gingival surface and is a common pathogen in the onset of periodontitis. This bacterium was thought to grow strictly by fermentation, but recent work by a graduate student in Dr. Saffarini’s lab indicated that this bacterium can grow by respiration. One of the problems of genetically manipulating P. gingivalis is the low efficiency of transformation. To address this problem, I have been working on generating mutants that lack the restriction systems that digest foreign DNA. Mutants are generated by cloning DNA upstream and downstream of the restriction system genes into the suicide plasmid that was generated in our lab. Mutants are selected and confirmed by PCR. The mutants are then tested for efficiency of transformation by using the plasmid pT-Cow that replicates in P. gingivalis