Investigating the diversity, molecular epidemiology, competitive influence and therapeutic potential of pneumococcal bacteriocins using large genome datasets (360G-Wellcome-206394_Z_17_Z)

Genomics has revolutionised infectious disease research. The rapidly growing volume of genomic data allows unprecedented depth and breadth of discovery. High quality genome sequence data from well-sampled studies are advancing our understanding of fundamental aspects of microbiology, epidemiology, population biology and microbial evolution. My group is among those at the forefront of this change: e.g. we recently published an analysis of 5,405 pneumococcal genomes. Five years ago this was impossible. My research is focused on Streptococcus pneumoniae (the ‘pneumococcus’), a leading global pathogen. My particular recent focus is bacteriocins – antimicrobials produced by bacteria to kill other bacteria. We analysed ~350 pneumococcal genomes for evidence of one type of bacteriocin cassette associated with niche competition and discovered that all pneumococci maintained this cassette and that it was genetically highly diverse. Surprisingly, one-third of the genomes also possessed genes encoding either a novel circular bacteriocin or a lantibiotic bacteriocin. Subsequently, we identified > 10 novel bacteriocins among ~500 pneumococcal genomes, a much higher frequency than expected. Why do pneumococci possess so many different bacteriocins? Using large genome datasets, we will provide an unprecedented, highly-detailed investigation of pneumococcal bacteriocins and assess their potential as novel antibiotics.