Background: Streptococcus mutans (S. mutans) is one of the main agents of caries formation, mainly because of the ability to form biofilms on the tooth surface. Bacteriophage of S. mutans are viruses that can attack and limit the pathogenic activity of S. mutans, hence limiting their cariogenic effect and preventing dental caries. There is a deficiency in the literature on the successful isolation of phage against S. mutans. Aims: The purpose of this study is to isolate S. mutans strains from clinical plaque samples, screen those samples for phage and test them against laboratory type cultures for phage. Methods: Thirty-eight clinical plaque samples were collected from participants using ESwab (Copan Italia, Brescia, Italy) and cultured on Brain Heart Infusion (BHI) and Tryptone-yeast-cysteine-sucrose-bacitracin (TYCSB) agars to isolate S. mutans strains. Following isolation and identification by Gram stain and PCR, phage screening by spot assay against laboratory type cultures was carried out. Six NCTC S. mutans strains (10832, 10919, 10920, 10923, 11060, 11061) and twelve type strains provided by Newcastle University (S. mutans UA159, 10449, UA140, Ingbritt, GS5, sobrinus 12279, gordonii DL1, sanguinis SK36, oralis 34, tigurinus JP1BV1, oligofermentans LR11BV4 and Actinomyces oris MG1) were all used for spotting. Results: The isolation of S. mutans strains from the clinical samples was successful. TYCSB agar showed to be selective for S. mutans while BHI media showed rich growth of different colonies. Gram stain was performed on the suspected colonies and confirmed later by PCR for S. mutans. On spot assay, no evidence of phage lysis was found within pooled filtrate samples against NCTC type strains and Newcastle type strains. Conclusion: The isolation of S. mutans from clinical samples was achieved using TYCSB media. Phage isolation was unsuccessful from the 38 clinical plaque samples probably due to low frequency of their natural occurrence. Isolation of Streptococcus mutans and bacteriophage from human plaque samples
Citation
Ahmed, H., Flockhart, A., Foley, S., & Foley, J. (2019). Isolation of Streptococcus Mutans and its Bacteriophage from Human Plaque Samples. Saudi Journal of Oral and Dental Research, 4(8), 561-564. https://doi.org/10.21276/sjodr.2019.4.8.10
