Isolation and Characterization of Streptococcus mutans Phage as a Possible Treatment Agent for Caries

Streptococcus mutans is a key bacterium in dental caries, one of the most prevalent chronic infectious diseases. Conventional treatment fails to specifically target the pathogenic bacteria, while tending to eradicate commensal bacteria. Thus, caries remains one of the most common and challenging diseases. Phage therapy, which involves the use of bacterial viruses as anti-bacterial agents, has been gaining interest worldwide. Nevertheless, to date, only a few phages have been isolated against S. mutans. In this study, we describe the isolation and characterization of a new S. mutans phage, termed SMHBZ8, from hundreds of human saliva samples that were collected, filtered, and screened. The SMHBZ8 genome was sequenced and analyzed, visualized by TEM, and its antibacterial properties were evaluated in various states. In addition, we tested the lytic efficacy of SMHBZ8 against S. mutans in a human cariogenic dentin model. The isolation and characterization of SMHBZ8 may be the first step towards developing a potential phage therapy for dental caries.