Dental plaque-What does it look like on a molecular level?
The oral biofilm (dental plaque) is a complex network of bacteria and host tissue. We are using protein X-ray crystallography to study its molecular components in detail to understand how it is built up and how it works.
The plaque on our teeth is built up from salivary proteins, bacteria and polysaccharides. In a normal bacterial flora the biofilm mainly consists of bacteria that protect against the pathogenic microorganisms that cause caries and other oral diseases. However, if the environment in the oral cavity is changed, the pathogenic bacteria may proliferate and cause disease. We are studying structure and function of proteins that are used by bacteria to crosslink to other bacteria and proteins in the biofilm. We have focused on surface proteins from the early colonizers Streptococcus gordonii and Actinomyces naeslundii as well as from the late colonizer Porphyromonas gingivalis. The aim of our projects is to crystallize the proteins and solve their three-dimensional structures using X-ray crystallography. The structures give a picture of the proteins on the atomic level and constitute important tools for understanding mechanisms underlying the formation of plaque as well as the difference in binding between commensal and more pathogenic bacteria.