Document Type : Research Paper


College of dentistry-Anbar university


According to estimates, the human oral cavity can harbour 700–1000 different species of bacteria, which are associated with periodontal and dental problems such as dental caries. Therefore, bacterial infections in the oral cavity may lead to significant health consequences, therefore early and correct identification is essential for effective treatment. This study has tried to create a multiplex PCR (m-PCR) procedure to detect six pathogenic bacteria frequently found in oral cavity infections: Streptococcus oralis, Streptococcus mutans, Porphyromonas gingivalis, Fusobacterium nucleatum, and Veillonella parvula. To confirm the sensitivity of the m-PCR assay, the assay was able to detect as little as 250 pg/μL of genomic DNA from each target bacterium, demonstrating high sensitivity. In conclusion, we have developed a rapid and reliable m-PCR assay for the simultaneous detection of six pathogenic bacteria frequently found in oral cavity infections. This assay has the potential to be a valuable tool for the early and accurate diagnosis of oral cavity bacterial infections, leading to more effective treatment and improved patient outcomes.


Main Subjects

[1] Arweiler, N.B. and L. Netuschil, The oral microbiota. Microbiota of the human body: implications in health and disease, 2016: p. 45-60.
[2] Mutha, N.V., et al., Transcriptional profiling of coaggregation interactions between Streptococcus gordonii and Veillonella parvula by Dual RNA-Seq. Scientific reports, 2019. 9(1): p. 7664.
[3] Sedghi, L., et al., The oral microbiome: Role of key organisms and complex networks in oral health and disease. Periodontology 2000, 2021. 87(1): p. 107-131.
[4] Mohammed, W.K., N. Krasnogor, and N.S. Jakubovics, Streptococcus gordonii Challisin protease is required for sensing cell--cell contact with Actinomyces oris. FEMS microbiology ecology, 2018. 94(5): p. fiy043.
[5] Jakubovics, N.S., Intermicrobial interactions as a driver for community composition and stratification of oral biofilms. Journal of molecular biology, 2015. 427(23): p. 3662-3675.
[6] Davey, M.E. and G.A. O'toole, Microbial biofilms: from ecology to molecular genetics. Microbiology and molecular biology reviews, 2000. 64(4): p. 847-867.
[7] Bowen, W.H., et al., Oral biofilms: pathogens, matrix, and polymicrobial interactions in microenvironments. Trends in microbiology, 2018. 26(3): p. 229-242.
[8] Kolenbrander, P.E., et al., Communication among oral bacteria. Microbiology and molecular biology reviews, 2002. 66(3): p. 486-505.
[9] Jakubovics, N.S., S.A. Yassin, and A.H. Rickard, Community interactions of oral streptococci. Advances in applied microbiology, 2014. 87: p. 43-110.
[10] Choo, S.W., et al., Transcriptomic Responses to Coaggregation between Streptococcus gordonii and Streptococcus oralis. Applied and Environmental Microbiology, 2021. 87(22): p. e01558-21.
[11] Contreras, A., et al., Periodontal microbiology in L atin A merica. Periodontology 2000, 2015. 67(1): p. 58-86.
[12] Parahitiyawa, N., et al., Exploring the oral bacterial flora: current status and future directions. Oral diseases, 2010. 16(2): p. 136-145.
[13] Do, T., et al., Population structure of Streptococcus oralis. Microbiology, 2009. 155(Pt 8): p. 2593.
[14] Hirschfeld, J. and T. Kawai, Oral inflammation and bacteremia: implications for chronic and acute systemic diseases involving major organs. Cardiovascular & Haematological Disorders-Drug Targets (Formerly Current Drug Targets-Cardiovascular & Hematological Disorders), 2015. 15(1): p. 70-84.
[15] Chalmers, N.I., et al., Characterization of a Streptococcus sp.-Veillonella sp. community micromanipulated from dental plaque. Journal of bacteriology, 2008. 190(24): p. 8145-8154.
[16] Cross, B.W. and S. Ruhl, Glycan recognition at the saliva–oral microbiome interface. Cellular immunology, 2018. 333: p. 19-33.
[17] Yoshida, Y., et al. Streptococcal receptor polysaccharides: recognition molecules for oral biofilm formation. in BMC Oral Health. 2006. Springer.
[18] Yadav, R.K. and V. Krishnan, New structural insights into the PI‐2 pilus from Streptococcus oralis, an early dental plaque colonizer. The FEBS Journal, 2022. 289(20): p. 6342-6366.
[19] Xu, H., et al., Streptococcal co-infection augments Candida pathogenicity by amplifying the mucosal inflammatory response. Cellular Microbiology, 2014. 16(2): p. 214-31.
[20] Diaz, P.I., et al., Using high throughput sequencing to explore the biodiversity in oral bacterial communities. Molecular Oral Microbiology, 2012. 27(3): p. 182-201.
[21] Palmer, R.J., Jr., et al., Mutualism versus independence: strategies of mixed-species oral biofilms in vitro using saliva as the sole nutrient source. Infection Immunology, 2001. 69(9): p. 5794-804.
[22] Luo, A., et al., Formation, development, and cross-species interactions in biofilms. Frontiers in Microbiology, 2022. 12: p. 3982.
[23] Lapa, S., et al., Multiplex PCR for identification of bacterial pathogens of infectious pneumonia. Russian journal of bioorganic chemistry, 2020. 46: p. 859-861.