| dc.description.abstract | Abstract
Campylobacteriosis is common in both developing and developed countries. Although there
had been numerous studies performed to gain a better understanding of the disease, much still
remains to be unravel. In this project, the interactions between the bacteria and host cells or
organisms were interrogated. Raman based imaging was initially investigated using an
established Salmonella Typhimurium and cell infection model. The results obtained showed
the potential for real-time imaging. However, due to the instability of the laser system of the
microscope, reproducible results could not be obtained. Therefore, this technique was not
applied to Campylobacter jejuni. Zebrafish embryo was established as a new infection model
suitable for C. jejuni studies. C. jejuni strains and mutants were screened using this model to
determine their virulence. This model was used to screen two type six secretion system
mutants constructed in this study. The results obtained showed that one of the mutants,
Cj1DtssM(syn)::kanR_cas, was attenuated in the ZFE model. Subsequent competitive index
challenges performed in piglets with C. jejuni wild-type and the two T6SS mutants, also
showed that Cj1DtssM(syn)::kanR_cas was attenuated. Both T6SS mutants had shown
increased adherence to macrophages and Cj1DtssM(syn)::kanR_cas also showed increased
cell invasion. Together, these findings suggested that the T6SS is involved in establishment
of infection in ZFE and piglet and as well as in adhesion and invasion of macrophages. | en_GB |
