The main focus of Dr. O'Toole's laboratory is the study of complex surface-attached bacterial communities known as biofilms. Biofilms can form on a wide variety of surfaces including catheter lines, surgical implants, contact lenses, the lungs of patients with cystic fibrosis, industrial and drinking water pipelines, and on the surfaces of plant roots. In most natural, clinical, and industrial settings bacteria live predominantly in biofilms and not as planktonic (free-swimming) cells such as those typically studied in the laboratory. Bacteria growing in biofilm communities are of great interest to the medical community, because these bacteria become highly resistant to antibiotics by an as yet unknown mechanism. In his lab, Dr. O'Toole studies the molecular genetic basis of the early events in biofilm formation on abiotic surfaces, including the role of the messenger c-di-GMP. He also investigates bacterial biofilms on airway epithelial cells, with the goal of better understanding host-pathogen interactions and developing new anti-biofilm interventions.