Biofilms are communities of microbes typically found on surfaces or interfaces.  One of the hallmarks of biofilms is their high level resistance to a wide-range of antimicrobial agents.  This resistance makes biofilms very difficult to eradicate.  Biofilm formation is a regulated process that involves the transition between planktonic (free-swimming) and surface-attached bacteria.  This transition occurs in response to a variety of environmental cues including the nutritional status of the environment.  A model for biofilm formation in Pseudomonas aeruginosa, an opportunistic pathogen, is shown below.  

Research Projects 

The O’Toole lab is interested in two different aspects of biofilm formation. 

First, what are the molecular mechanisms and regulatory pathways that control the transition from planktonic growth to a surface-attached lifestyle?  To learn more about our recent work, click here.  To check out some earlier studies, please go to this link.  

We are also interested in biofilm antibiotic resistance.  Previous studies in the lab focused on the resistance of biofilms grown on non-living surfaces.  You can learn more about this work here.  

Our recent studies have shifted focus to study the biofilm antibiotic resistance of P. aeruginosa grown on the surface of host cells.  In particular, we are interested in P. aeruginosa interactions with host airway epithelial cells. P. aeruginosa is an important lung pathogen, especially for individuals with cystic fibrosis.  In collaboration with Bruce Stanton and his group here at Dartmouth, we have developed a new model system to explore P. aeruginosa biofilm formation and antibiotic resistance on airway cells.  Go here to learn more about this exciting new project.