Coaggregation with Actinomyces Naeslundii Reduces Corynebacterium Matruchotii Cell Division Rate and Increases in Cell Length

Corynebacterium matruchotii is believed to form a scaffold-like structure within the human oral cavity so that other species of bacteria have a place to bind. Many types of bacteria may be found within oral biofilms, commonly referred to as dental plaque. Actinomyces naeslundii are associated with dental caries and they are frequently found in dental plaques. Previous studies in our lab have demonstrated that A. naeslundii has a greater coaggregation rate with C. matruchotii than other Actinomyces species. The purpose of this study is to determine the effect of coaggregation with A. naeslundii on C. matruchotii growth kinetics. In this study, A. naeslundii grew in liquid cultures and the growth curves were measured. C. matruchotii was grown in the presence of heat killed A. naeslundii cells to determine the impact coaggregation has on cell growth. Additionally, plate counting was conducted at four time points. When grown with A. naeslundii cells C. matruchotii exhibited a reduction in cell growth and the C. matruchotii cells grew longer. Interactions between these species of bacteria may have implications for the role of the oral microbiome in the transition from oral health to disease.