Thermophilin 110 inhibits growth and biofilm formation of Streptococcus mutans

Authors: Renye, John; Steinberg, Dennis

Submitted to: Current Microbiology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/12/2021
Publication Date: 6/16/2021
Citation: Renye Jr, J.A., Steinberg, D.H. 2021. Thermophilin 110 inhibits growth and biofilm formation of Streptococcus mutans. Current Microbiology. https://doi.org/10.1016/j.btre.2021.e00647.
DOI: https://doi.org/10.1016/j.btre.2021.e00647

Interpretive Summary: Tooth decay is caused by the conversion of sugar to acid by specific bacteria within the oral cavity. Although good oral hygiene, including brushing and flossing, can help to prevent the development of dental cavities, they remain a global oral health burden affecting both children and adults. Recently, laboratory and clinical studies have suggested that beneficial bacteria, called probiotics, could prevent bad breath, cavities and periodontal disease by inhibiting the colonization or growth of bacteria associated with these conditions. This study reports the potential for using a dairy starter culture to prevent the formation of dental cavities. The yogurt culture naturally produced a compound which inhibited the growth of an oral bacterium commonly associated with tooth decay. In addition, the compound was shown to prevent aggregation of the oral bacterium, thus preventing the formation of a film that adheres to the tooth surface. Results from this study suggest the yogurt culture could serve as an oral probiotic, or the compound could be included as a component within pastes or rinses to improve oral health.

Technical Abstract: Cell free supernatants (CFS) from five bacteriocin-producing strains of Streptococcus thermophilus were screened for activity against the oral pathogen Streptococcus mutans UA159. S. thermophilus B59671, which naturally produces thermophilin 110, was the only strain that inhibited the growth of S. mutans in broth and agar medium. Thermophilin 110 at concentrations of 80 AU ml-1 or higher prevented the growth of S. mutans in batch culture; while 160 AU ml-1 was required to prevent biofilm formation. Co-culturing S. thermophilus B59671 and S. mutans UA159 was also shown to disrupt biofilm formation, which may be a result of thermophilin 110 inhibiting the growth of planktonic cells thus preventing their attachment to surfaces. These results suggest that S. thermophilus B59671 has the potential to serve as a probiotic for improving oral health; or that thermophilin 110 could be used as a natural antimicrobial in products developed to prevent tooth decay.