5 The role of quorum-sensing in the virulence of Pseudomonas ...

determine genes that are important for acute and chronic respiratory infection as
well as genes that are essential for persistence in the nasopharynx and lungs.
5.3.3 The LES isolates versus the reference strains, PAO1 & PA14
The LES isolates have been compared in several research papers to the P.
aeruginosa reference strains, PAO1 and PA14. In a Drosophila fly infection model
(Salunkhe et al. 2005), both LES431 and LES400 were shown to be more virulent
than PAO1. In the C. elegans model of infection (Winstanley C, University of
Liverpool, unpublished), all the LES isolates had a lower LT50 than PAO1. In a
chronic infection model within rats (Kukavica-Ibrulj et al. 2008), the growth curve
of the bacteria within the lungs and thereby the lung colonisation capability were
shown to be similar for LESB58, PAO1 and PA14.
In this thesis the LES isolates and the reference strains have been analysed using a
newly developed acute respiratory model as described in methods section. Mice
infected with PAO1 did not survive beyond 24 hours and PA14-infected mice did
not survive beyond 18 hours. LES431 infected mice had a similar survival curve to
PA14. This coincides with significantly (P