My main research interests focuses around alternative anti microbials with my main interest in Bacteriocins. Bacteriocins are proteins expressed in a bacteria during the SOS response to kill like-bacteria to reduce competition from the surrounding area. They are highly specific and they kill bacteria with high efficiency. I have focused on the mode of action and the structural stability of these proteins and other bacterial toxins.
During my PhD I worked on the mode of action and interactions of the E. coli bacteriocin, colicin E3. It is a plasmid encoded cytotoxin that kills target cells by cleaving the 16S rRNA of the ribosome, which leads to the inhibition of protein synthesis. Using single point mutagenesis I identified the active site of the ribosomal RNase (rRNAse) domain and the amino acids involved [Walker, Lancaster et al, 2004]. Two of the mutants became unfolded by the mutation made so I investigated the nature of the unfolding and the refolding of the protein when interacting with its immunity protein (Papadakos et al, 2015).
I also analysed the interaction of the E3 rRNase with the ribosome by labelling the rRNase domain with a fluorophore and using ultracentrifugation and size exclusion chromatography techniques [Lancaster, 2005]. As part of this research I was awarded an EMBO short term fellowship to work at the Universitaet Witten/Herdecke, Germany. I established this collaboration to determine which step of translation is inhibited when the 16S rRNA is cleaved by E3 rRNase. This fellowship led on to a post doctoral research position where I finalised this research and developed a biochemical assay to analyse the progressive decrease of A-site binding of amino-acyl tRNA’s.
I then took a research position at the National Institute of Research and Control where I developed quality control procedures for novel vaccines for nosocomial infections (Clostridium difficile) and neonatal infections (Group B Streptococcus). This research involved using biochemical, biophysical and immunological techniques to determine the stability of the vaccine and its effectiveness.
My current research focuses on my interest in bacteriocins and their use in prevention or treatment of disease. I have a particular interest in nosocomial infections after my research projects at the National Institute of Biological Standards and Control and I am investigating bacteriocins produced in Clostridium difficile and Klebsiella pneumoniae that could be a potential treatment for these infections.