Inhibitory Effects of Low-Energy Pulsed Ultrasonic Stimulation on Cell Surface Protein Antigen C through Heat Shock Proteins GroEL and DnaK inStreptococcus mutans

Abstract

This study concerns the use of low-energy pulsed ultrasound as nondestructive photodynamic antimicrobial therapy for controlling dental plaque. We examined the antibacterial and bactericidal effects of low-energy pulsed ultrasound on mutans streptococci and its inhibitory effects on bacterial cell adhesion of Streptococcus mutans. The results indicated weak antibacterial and bactericidal effects. However, ultrasonic stimulation for less than 20 min markedly decreased bacterial cell adhesion. To analyze the mechanism underlying the inhibitory effect, we examined cell surface protein antigen C (PAc) and glucosyltransferase I (GTF-I) expression in S. mutans. The levels of PAc gene and protein expression were markedly decreased by ultrasonic stimulation for 20 min. However, no change in GTF-I expression was observed. The expression of stress response heat shock proteins GroEL and DnaK was also examined. GroEL and DnaK levels were significantly decreased by ultrasonic stimulation, and the expression of the PAc protein was also diminished upon the addition of GroEL or DnaK inhibitors without ultrasonic stimulation. These observations suggest that the expression of the PAc protein in S. mutans may be dependent on heat shock proteins. Thus, low-energy pulsed ultrasound decreases bacterial adhesion by the inhibitory effect on the PAc protein and heat shock protein expression and may be useful as photodynamic antimicrobial chemotherapy in controlling dental plaque.

Electrophoresis and spectrometric analyses of adaptation-related proteins in thermally stressed Chromobacterium violaceum

“…This result reinforces that 30°C is the optimum growth temperature for C. violaceum, in accordance with a review by Hungria et al (2004). In addition, it was previously demonstrated that, in Streptococcus mutans, the expression of proteins related to bacterial cell adhesion was dependent upon the heat shock proteins DnaK and GroEL, suggesting that these chaperones are involved in other cellular processes besides stress response (Ishibashi et al, 2010). This is consistent with the results shown in this work, as heat shock protein chaperones were expressed under all tested conditions.…”

“…Many of the stress responses overlap with one another in bacteria (Ishibashi et al, 2010) and adaptive reactions involve general changes in metabolism as well as in gene transcript levels (Jozefczuk et al, 2010;Gomes et al, 2012). The expression of heat shock genes in Gram-negative proteobacteria is positively modulated by the transcriptional regulator RpoH, the σ 32 subunit of RNA polymerase, which induces the expression of proteins involved in the response to heat and cold stress (Yura et al, 1993;El-Samad et al, 2005).…”

Antimicrobial and Antibiofilm Activity against Streptococcus mutans of Individual and Mixtures of the Main Polyphenolic Compounds Found in Chilean Propolis

“…Since many years ago, the S. mutans has been identified as the main microorganism responsible for initiating the colonization of the oral cavity, and it is capable to generate an acidic ambience favorable for the degradation of tooth mineral and protein material [18]. The diversity in its biological activity has been investigated in numerous studies with high concentrations of entire polyphenols present in EP, especially certain types of polyphenols as flavonoids.…”

Comparative Evaluation of Combinatory Interaction between Endocannabinoid System Compounds and Poly‐L‐lysine against Streptococcus mutans Growth and Biofilm Formation

“…S. mutans has been identified as the major bacteria responsible for initiating colonization of the oral cavity, and it is capable of generating an acidic environment that results in decalcification of the tooth [26]. Dental plaque control improved with the use of antiseptics, such as chlorhexidine and its derivatives, which affect oral bacteria and their attachment [27].…”