How does S. pneumoniae acquire extracellular DNA from its natural environment to drive antibiotic resistance?

Understanding the flow of genetic information between individuals and communities is fundamental to our understanding of how biological systems function. In bacteria, this genetic exchange can be driven by a process called competence, where cells integrate foreign DNA from their environment directly into their genomes. This includes genes involved in virulence and antibiotic resistance which provide fitness advantages during infection.

Natural competence was first studied in Streptococcus pneumoniae, a species of bacteria that colonises the respiratory tract of healthy people, but also causes devastating infections if they escape and colonise other areas of the body. S.pneumoniae acquires antibiotic resistance through the uptake of extracellular DNA from other bacterial species found in their natural environment. This study aims to use a combination of molecular biology, microfluidic devices, and time-lapse imaging to unravel how S.pneumoniae exchanges genetic material with other bacteria species. We will engineer S.pneumoniae to express fluorescent proteins when they integrate extracellular DNA into their genomes, allowing us to determine the specific environmental conditions that facilitate DNA transfer within mixed bacterial communities. This knowledge the may ultimately lead to new insights on how S.pneumoniae acquires antibiotic resistance and evades vaccines.