Identification of niche-specific virulence factors via experimental evolution of Streptococcus pneumoniae

The pneumococcus is a bacterium that causes severe diseases throughout the world, but particularly in poorer countries. It is the most common cause of death from infectious disease in children under five. We don't have a vaccine that protects against every type of pneumococcus, and what makes pneumococcus so deadly is the ability to adapt to different challenges in different sites in the human body. Many people have pneumococcus living harmlessly in their noses and mouths, but it is also able to survive in the lungs (where it can cause pneumonia) and the lining of the brain (where it causes meningitis).

This five-year project aims to explain how pneumococcus thrives in different places. By comparing the genes of bacteria that cause different types of disease I will be able to find out which genes are required to infect certain organs. I will then construct bacteria that lack these genes and find out if they are still able to cause disease. This will help us understand what changes in the ‘safe’ bacteria in our noses which allows them to cause disease. I aim to find important bacterial proteins that could be targeted in new vaccines or drugs that could control pneumococcal disease.