The effect of Pf4 filamentous phage infection of its host, pseudomonas aeruginosa.

• Main Author: Ng, Amanda Hui Qi.
• Other Authors: School of Biological Sciences
• Format: Final Year Project
• Language: English
• Published: 2013
• Subjects: DRNTU::Science::Biological sciences::Microbiology::Microbial ecology
• Online Access: http://hdl.handle.net/10356/52471
• Institution: Nanyang Technological University

Bacteriophages have significant roles in the evolution and diversity of bacteria. The Pf4 filamentous phage is important for biofilm formation and virulence of its host, Pseudomonas aeruginosa. It is thus interesting to compare the genetic response between wild-type P. aeruginosa and the Pf4 knock-out strain. Here, quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) was used to quantify the gene levels of pyoverdine- and multi-drug efflux pump-related genes in P. aeruginosa PAO1 and ∆Pf4. These genes (i.e. pvdO, pvdN, mexE and mexF) were shown to be highly upregulated in the Pf4 mutant strain. Additionally, the exogenous add-back of wild-type (WT) and super-infective (SI) forms of the Pf4 filamentous phage reduced the expression of these genes in the Pf4 mutant strain. Furthermore, the add-back of SI phages to PAO1 cultures slightly increased the expression of pyoverdine-related genes. These results suggest that Pf4 phage impacts strongly on the regulation of pyoverdine- and multidrug-efflux pump-related genes to enhance the chances of successful infection by P. aeruginosa.