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

exceed 42kb. Time constraints restricted this work being achieved during this
project; as the current selection of capture vectors and strains available were not
comparable with this aim.
The most important outcome of this project is the novel genomic island discovery of
E105-leuX. This is the first record of the use of the genomic island capture
technique to capture a genomic island from a bacterial species other than P.
aeruginosa. The technique was successfully used to compare genomic islands to
previously defined island and determine similarity, for example PAO1-lys10 versus
KR115-lys10 and KR159-lys10. The PA14-lys10 has been introduced into PA14
deletant mutants in experiments performed by Ewan Harrison (Harrison E, PhD
thesis, University of Leicester, unpublished) in a complementary experiment. This
molecular biology tool is very important as the targeting regions will in most cases
be conserved among majority of the members of the same species. This allows for
comparative studies of these regions. The technique has now opened doorways for
allowing the roles of genomic islands to be elucidated via functional studies. The
genomic islands can be introduced into strains that lack them and experiments to
examine the increased fitness of the bacteria could be performed. These kinds of
studies could be important for pathogenicity islands, to examine how they
contribute to the virulence of a pathogen. These experiments could be used to
support the central dogma, pathogencity island cause non-pathogens to become
pathogens. Functional experiments could be performed with E105-leuX to
determine if the type III RM system is functional. A number of approaches could be
considered such as purifying the mod and res subunit proteins and performing in
vitro assays. Another approach is preparing the genomic DNA of E. coli E105 and
attempting to restrict the DNA with enzymes that such as EcoP15I to see if the
methylation has protected the genomic DNA.
3.6 Conclusion and further work
The aim of the project was to produce a generic genomic island capture method.
This has been achieved by capturing genomic islands from a number of bacterial
species P. aeruginosa and E. coli as well supporting work to capture genomic
islands from A. baumannii (Shaikh F, PhD thesis, University of Leicester,
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