Pseudomonas aeruginosa is one of the most common pulmonary pathogens (Overhage, et. al., 2006). It is an opportunistic and highly virulent pathogen that rarely affects healthy people; in fact, P. aeruginosa affects primarily immune-compromised people such as those suffering from cystic fibrosis (Kohler, et al., 2000). This increased virulence in immune-compromised people has been attributed to its ability to form biofilms, its motility and antibiotic resistance (Overhage, et al., 2006)(Parsek & Fuqua, 2003). By understanding the genes involved in swarming a virulent motility phenotype of P. aeruginosa, progress can be made in eliminating its harmful effects on humans. In order to do this, we attempted to isolate and sequence the genes involved in swarming. Tn5 (a transposon) was inserted into non-swarming mutant P. aeruginosa DNA in order to reinstate swarming. The occurrence of the swarming phenotype indicated that Tn5 interrupted a gene involved in swarming repression. To identify the sequences of these genes that were interrupted, the genomic DNA was prepared, digested and subjected to inverse PCR. During the inverse PCR process, reproducible fragments were not obtained indicating problems in the isolation or preparation of the DNA. In order to identify why reproducible fragments were not being obtained, control primers were designed to ensure that Tn5 was being inserted and that the DNA was being prepared correctly. The results indicate that template preparation and Tn5 insertion was correct. These results suggest that the small reproducible fragments amplified originally assumed to be excess primer could be the genes responsible for swarming.
Abby Schultz, ’11 Excelsior, MN
Majors: Biochemistry and Molecular Biology, Art and Art History
Bailee Beauman, ’11 Aurora, CO
Sponsor: Jeffrey Cardon