A Multidisciplinary Study of Salmonella-Protozoa Interactions on Surfaces, Liquid Culture and Soil: Bacterial Phenotype Dynamics

The aims of this project are to elucidate protozoa- salmonellae interactions on surfaces, in aquatic systems and in soils. Sophisticated image analysis techniques and a Fluorescence-Activated Cell Sorter (FACS) will be employed. Mathematical modelling and data analysis will be used to study interaction dynamics, allowing comparison of mechanisms and rates. Salmonellae populations will be examined using a gfp gene reporter, live-dead, and cell proliferation and cell cycle analysis. Phenotypic change of salmonellae on passage through protozoa will be studied, particularly induction of resistance to antibiotics, filamentous growth and resuscitation of viable but unculturable cells. Methods used to detect salmonellae in the environment will include immunomagnetic capture, Nycodenz extraction from soil and protozan culture to detect intracellular growth.