Investigating the Determinants of Host Range Specificity of Pseudomonas aeruginosa Phage

Phage therapy, or the use of bacteriophages (phages) to kill pathogenic bacteria, represents an alternative strategy to antibiotics in combating bacterial disease in the face of growing antibiotic resistance. To use phage therapy as an antibacterial treatment, we need to understand how the phages choose their host. The following thesis outlines my work studying two particular Pseudomonas aeruginosa phages, D3 and JBD44a, which I have chosen based on structural similarity and host diversity. I have shown that D3-27 and JBD44-39 are required for complete phage particles as well as involved in specificity through heterologous complementation experiments. I have determined that JBD44a can be blocked by LPS from its host strain PA14. I have also determined that D3-27 specifically and immediately modifies LPS from its host strain PAO1 through the C-terminus. The experiments outlined have shown that D3-27 and JBD44 are involved in specificity and are found in the phage tail.M.Sc