Abstract
Streptococcus mutans is one of the principal pathogens for the development of dental caries. Oral biofilms formed by S. mutans are constructed of insoluble glucan formation induced by the principal enzymes, GTF-I and GTF-SI, in sucrose-containing conditions. However, as another means of biofilm formation, extracellular DNA (eDNA) and membrane vesicles (MVs) are also contributors. To explore the roles of eDNA and MVs for biofilm formation, short and whole size pure DNAs, two types of sub-purified DNAs and MVs were extracted from S. mutans by beads destruction, treatment of proteinase K, and ultracentrifugation of culture supernatant, and applied into the biofilm formation assay using the S. mutans UA159 gtfBC mutant, which lost GTF-I and GTF-SI, on a human saliva-coated 96 well microtiter plate in sucrose-containing conditions. Sub-purified DNAs after cell lysis by beads destruction for total 90 and 180 s showed a complex form of short-size DNA with various proteins and MVs associated with GTF-I and GTF-SI, and induced significantly higher biofilm formation of the S. mutans UA159.gtfBC mutant than no sample (p < 0.05). Short-size pure DNA without proteins induced biofilm formation but whole-size pure DNA did not. Moreover, the complex form of MV associated with GTFs and short-size DNA showed significantly higher biofilm formation of initial colonizers on the human tooth surface such as Streptococcus mitis than no sample (p < 0.05). The short-size DNAs associated with MVs and GTFs are important contributors to the biofilm formation and may be one of additional targets for the prevention of oral biofilm-associated diseases.
Highlights
The formation of oral biofilms is the most important physical biological activity of oral bacteria and provides survival conditions for bacteria in the oral cavity when the physical removal of the bacteria is attempted by oral brushing and rinsing [1,2,3]
The short-size DNAs associated with membrane vesicles (MVs) and GTFs are important contributors to the biofilm formation and may be one of additional targets for the prevention of oral biofilm-associated diseases
Water-insoluble glucan synthesized using GtfB (GTF-I)- and GtfC (GTF-SI)-glucosyltransferases, which are encoded by gtfB and gtfC, promote adhesion to tooth surfaces, aggregation of bacterial cells within the biofilm, and mature biofilm formation with complex bacteria in conditions supplemented with sucrose [10]
Summary
The formation of oral biofilms is the most important physical biological activity of oral bacteria and provides survival conditions for bacteria in the oral cavity when the physical removal of the bacteria is attempted by oral brushing and rinsing [1,2,3]. More than 700 species of oral microorganisms have been detected in the oral cavity, and some colonizers attach to the tooth surface, interact with each other, aggregate, and form complex bacteria biofilms [4,5,6]. Streptococcus mutans is a type of bacteria that attaches to the tooth surface and is one of the principal pathogens for the development of dental caries [7,8]. Water-insoluble glucan synthesized using GtfB (GTF-I)- and GtfC (GTF-SI)-glucosyltransferases, which are encoded by gtfB and gtfC, promote adhesion to tooth surfaces, aggregation of bacterial cells within the biofilm, and mature biofilm formation with complex bacteria in conditions supplemented with sucrose [10]. Surface-associated glucan-binding proteins (Gbps; GbpA, GbpB, GbpC, and GbpD)
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
