Sensitivity of the Periodontal Pathogen <i>Aggregatibacter actinomycetemcomitans</i> at Mildly Acidic pH

Bhattacharjee, Mrinal K.; Childs, Claiborne B.; Ali, Emdad

doi:10.1902/jop.2010.100590

Cited by 14 publications

(8 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These results are in agreement with the observed optimal pH range for growth of this bacterium 38 . The findings also suggest a greater abundance of Pg under acidic conditions (pH below 7), although optimum pH for growth is close to neutrality 39 . Maybe the association could be attributable to low salivary flow more than to pH.…”

Section: Discussionsupporting

confidence: 89%

“…38 The findings also suggest a greater abundance of Pg under acidic conditions (pH below 7), although optimum pH for growth is close to neutrality. 39 Maybe the association could be attributable to low salivary flow more than to pH. This information could help clinicians choose the best approach for treating periodontal infections caused by these microorganisms.…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Oral Microbiota, Periodontal Status, and Osteoporosis in Postmenopausal Females

Hernández-Vigueras

Martínez-Garriga

Sanchez

et al. 2016

Journal of Periodontology

View full text Add to dashboard Cite

show abstract

Section: Discussionsupporting

confidence: 89%

Section: Discussionmentioning

confidence: 99%

Oral Microbiota, Periodontal Status, and Osteoporosis in Postmenopausal Females

Hernández-Vigueras

Martínez-Garriga

Sanchez

et al. 2016

Journal of Periodontology

View full text Add to dashboard Cite

show abstract

“…After incubation for an additional 24 h, biofilms were quantified by crystal violet staining. As shown in Figure A, biofilm biomass of the wild‐type strain increased after the addition of fresh medium at pH 6.0, 7.0 or 8.0, consistent with the previous findings of Bhattacharjee et al However, a significant decrease in biomass occurred when the wild‐type biofilm was incubated in fresh medium at pH 5.0. Biomass of the D11S_1718‐1719 mutant was significantly less than that of the wild‐type at pH 6.0 and pH 5.0, but was restored to wild‐type levels when the deletion strain was complemented with a functional copy of the TA system.…”

Section: Resultssupporting

confidence: 90%

“…During growth of A. actinomycetemcomitans in broth culture, the pH of the medium drops from an initial pH 7.5 to pH 5.5‐6.0 when the culture is in stationary phase. Bhattacharjee et al previously showed that if the pH of spent medium was readjusted to neutral, A. actinomycetemcomitans continued to grow without requiring any other additives. This suggests that entrance into stationary phase may be dependent on environmental pH rather than depletion of available nutrients in the medium.…”

Section: Resultsmentioning

confidence: 99%

Identification and functional characterization of type II toxin/antitoxin systems in Aggregatibacter actinomycetemcomitans

Schneider

Weigel

Sztukowska

et al. 2018

Molecular Oral Microbiology

View full text Add to dashboard Cite

SummaryType II toxin/antitoxin (TA) systems contribute to the formation of persister cells and biofilm formation for many organisms. Aggregatibacter actinomycetemcomitans thrives in the complex oral microbial community subjected to continual environmental flux. Little is known regarding the presence and function of type II TA systems in this organism or their contribution to adaptation and persistence in the biofilm. We identified 11 TA systems that are conserved across all seven serotypes of A. actinomycetemcomitans and represent the RelBE, MazEF and HipAB families of type II TA systems. The systems selectively responded to various environmental conditions that exist in the oral cavity. Two putative RelBE‐like TA systems, D11S_1194‐1195 and D11S_1718‐1719 were induced in response to low pH and deletion of D11S_1718‐1719 significantly reduced metabolic activity of stationary phase A. actinomycetemcomitans cells upon prolonged exposure to acidic conditions. The deletion mutant also exhibited reduced biofilm biomass when cultured under acidic conditions. The D11S_1194 and D11S_1718 toxin proteins inhibited in vitro translation of dihydrofolate reductase (DHFR) and degraded ribosome‐associated, but not free, MS2 virus RNA. In contrast, the corresponding antitoxins (D11S_1195 and D11S_1719), or equimolar mixtures of toxin and antitoxin, had no effect on DHFR production or RNA degradation. Together, these results suggest that D11S_1194‐1195 and D11S_1718‐1719 are RelBE‐like type II TA systems that are activated under acidic conditions and may function to cleave ribosome‐associated mRNA to inhibit translation in A. actinomycetemcomitans. In vivo, these systems may facilitate A. actinomycetemcomitans adaptation and persistence in acidic local environments in the dental biofilm.

show abstract

“…In general, the optimal pH for bacterial growth is close to neutral, and microorganisms lose viability in acidic environments; however, some bacterial strains exhibit acid-neutralizing activity through amino acid fermentation and may thereby acquire resistance to acidity 35) . Because neither P. gingivalis nor A. actinomycetemcomitans are able to grow even in mildly acidic pH 36,37) , the acidic sodium fluoride solution reduced the cell viability of the tested microorganisms.…”

Section: Discussionmentioning

confidence: 98%

Effects of acidic sodium fluoride-treated, commercially pure titanium on periodontal pathogens and rat bone marrow cells

et al. 2014

View full text Add to dashboard Cite

The purpose of the present study was to clarify the potentiality of acidic fluoride solution in treating peri-implantitis. We examined bactericidal activity of fluoride solution against periodontal pathogens; and evaluated the effects of fluoride on titanium, and the effects on cell proliferation and differentiation of rat bone marrow cells on the fluoride-treated titanium. Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis were used to determine minimal inhibitory concentration (MIC) and shorttime exposure. The cells were seeded on the titanium surface with or without fluoride treatment. Then, cellular proliferation, differentiation and mineral deposition were analyzed. The MIC values for A. actinomycetemcomitans and P. gingivalis were 225 and 900 ppm F − , respectively. In short-time exposure test, both bacterial strains exhibited a significant decrease in a concentrationdependent manner. Cell proliferation and mineral deposition were significantly increased on the fluoride-treated surface. Within the limitation of this study, acidic sodium fluoride solution has the potentiality in treating peri-implantitis.

show abstract

Sensitivity of the Periodontal Pathogen Aggregatibacter actinomycetemcomitans at Mildly Acidic pH

Abstract: A. actinomycetemcomitans cells rapidly lost viability at even a mildly acidic pH. The problem was easily rectified by growing cells at a low glucose concentration.

Cited by 14 publications

References 30 publications

Oral Microbiota, Periodontal Status, and Osteoporosis in Postmenopausal Females

Oral Microbiota, Periodontal Status, and Osteoporosis in Postmenopausal Females

Identification and functional characterization of type II toxin/antitoxin systems in Aggregatibacter actinomycetemcomitans

Effects of acidic sodium fluoride-treated, commercially pure titanium on periodontal pathogens and rat bone marrow cells

Contact Info

Product

Resources

About