Oral Health and Dental Management

Characterization of the effects of Streptococcus mutans growth conditions on eDNA release

32^nd Asia Pacific Dental and Oral Health Congress

July 23- 24, 2018 Sydney, Australia

Miah Kim

Chonbuk National University, Republic of Korea

Posters & Accepted Abstracts: Oral Health Dent Manag

Abstract:

Background: Extracellular DNA (eDNA) is a component of the biofilm matrix, which also includes microbial cells, exopolysaccharides and proteins. Although many studies have examined eDNA, there is little information available regarding Streptococcus mutans eDNA. Method: To characterize Streptococcus mutans eDNA, we cultured the bacteria for 1 to 24 hours in medium with 1% sucrose or 1% glucose. We identified eDNA by using polymerase chain reaction and used DNA-binding dye, SYBR green I to measure the amount of eDNA. Result: We found that Streptococcus mutans eDNA has some differences from Streptococcus mutans genomic DNA and that eDNA is secreted at an early growth stage (â?¤1 h post-inoculation). Streptococcus mutans produced more eDNA in the supernatant and less eDNA in the pellet in 1% glucose than in 1% sucrose. Although Streptococcus mutans cultured in 1% sucrose had more colony forming units (CFUs), the pH values were higher and the CFU-normalized eDNA levels were lower compared to Streptococcus mutans cultured in 1% glucose. DNase treatment removed eDNA and significantly reduced the total dry weight (2.6 fold in 1% glucose and 1.4-fold in 1% sucrose). Conclusion: These results indicate that Streptococcus mutans produces different levels of eDNA in different media and that eDNA is an important component aggregator in Streptococcus mutans biofilms.

Biography :

Miah Kim is a Research Fellow at Chounbuk National University, Republic of Korea.

E-mail: miah2018@hanmail.net