Signaling Systems in Oral Bacteria

2019 ◽  
pp. 27-43 ◽  
Author(s):  
Daniel P. Miller ◽  
Richard J. Lamont
Keyword(s):  
Oral Bacteria ◽  
Signaling Systems

scholarly journals Interactions between Oral Bacteria: Inhibition of Streptococcus mutans Bacteriocin Production by Streptococcus gordonii

2005 ◽  
Vol 71 (1) ◽  
pp. 354-362 ◽  
Author(s):  
Bing-Yan Wang ◽  
Howard K. Kuramitsu
Keyword(s):  
Quorum Sensing ◽  
Streptococcus Mutans ◽  
Parent Strain ◽  
Oral Bacteria ◽  
Bacteriocin Production ◽  
Oral Streptococci ◽  
Streptococcus Gordonii ◽  
Signaling System ◽  
Signaling Systems ◽  
Bacteria Inhibition

ABSTRACT Streptococcus mutans has been recognized as an important etiological agent in human dental caries. Some strains of S. mutans also produce bacteriocins. In this study, we sought to demonstrate that bacteriocin production by S. mutans strains GS5 and BM71 was mediated by quorum sensing, which is dependent on a competence-stimulating peptide (CSP) signaling system encoded by the com genes. We also demonstrated that interactions with some other oral streptococci interfered with S. mutans bacteriocin production both in broth and in biofilms. The inhibition of S. mutans bacteriocin production by oral bacteria was stronger in biofilms than in broth. Using transposon Tn916 mutagenesis, we identified a gene (sgc; named for Streptococcus gordonii challisin) responsible for the inhibition of S. mutans bacteriocin production by S. gordonii Challis. Interruption of the sgc gene in S. gordonii Challis resulted in attenuated inhibition of S. mutans bacteriocin production. The supernatant fluids from the sgc mutant did not inactivate the exogenous S. mutans CSP as did those from the parent strain Challis. S. gordonii Challis did not inactivate bacteriocin produced by S. mutans GS5. Because S. mutans uses quorum sensing to regulate virulence, strategies designed to interfere with these signaling systems may have broad applicability for biological control of this caries-causing organism.

Attachment of oral bacteria to titanium surfaces: An SEM study

1994 ◽  
Vol 52 ◽  
pp. 468-469
Author(s):  
J. E. Laffoon ◽  
R. L. Anderson ◽  
J. C. Keller ◽  
C. D. Wu-Yuan
Keyword(s):  
Technical Problem ◽  
Titanium Implant ◽  
Oral Bacteria ◽  
Bacterial Cells ◽  
Thin Sections ◽  
Surface Ultrastructure ◽  
Sem Study ◽  
Key Factor ◽  
Titanium Surfaces

Titanium (Ti) dental implants have been used widely for many years. Long term implant failures are related, in part, to the development of peri-implantitis frequently associated with bacteria. Bacterial adherence and colonization have been considered a key factor in the pathogenesis of many biomaterial based infections. Without the initial attachment of oral bacteria to Ti-implant surfaces, subsequent polymicrobial accumulation and colonization leading to peri-implant disease cannot occur. The overall goal of this study is to examine the implant-oral bacterial interfaces and gain a greater understanding of their attachment characteristics and mechanisms. Since the detailed cell surface ultrastructure involved in attachment is only discernible at the electron microscopy level, the study is complicated by the technical problem of obtaining titanium implant and attached bacterial cells in the same ultra-thin sections. In this study, a technique was developed to facilitate the study of Ti implant-bacteria interface.Discs of polymerized Spurr’s resin (12 mm x 5 mm) were formed to a thickness of approximately 3 mm using an EM block holder (Fig. 1). Titanium was then deposited by vacuum deposition to a film thickness of 300Å (Fig. 2).

Oral Bacteria May Affect Pregnancy Outcome

2005 ◽  
Vol 35 (9) ◽  
pp. 48
Author(s):  
MICHELE G. SULLIVAN
Keyword(s):  
Pregnancy Outcome ◽  
Oral Bacteria

Antibacterial Flavonoids Against Oral Bacteria of Enterococcus Faecalis ATCC 29212 from Sarang Semut (Myrmecodia pendans) and Its Inhibitor Activity Against Enzyme MurA

2019 ◽  
Vol 16 (3) ◽  
pp. 290-296 ◽  
Author(s):  
Dikdik Kurnia ◽  
Eti Apriyanti ◽  
Cut Soraya ◽  
Mieke H. Satari
Keyword(s):  
Enzyme Activity ◽  
Enterococcus Faecalis ◽  
Ethyl Acetate Fraction ◽  
Antibacterial Activities ◽  
Oral Bacteria ◽  
Diffusion Method ◽  
Enzyme Activity Assay ◽  
Antibacterial Compounds ◽  
Ic50 Values ◽  
Positive Controls

Background: A significant number of antibiotics are known to inhibit peptidoglycan synthesis in the cross-linking stage, while the drug fosfomycin is the only one known to inhibit MurA. Escalated antibiotic resistance has had an impact on the efficacy of fosfomycin, thus demanding the discovery of suitable substitutes with improved potential for MurA inhibition. The aim of this work is to isolate antibacterial compounds from Sarang Semut (Myrmecodia pendans) and to evaluate their antibacterial activity against pathogenic oral bacteria of Enterococcus faecalis ATCC 29212 and inhibitory activity against MurA enzyme. Methods: The antibacterial compounds from Sarang Semut were isolated by a bioactivity-guided separation method with various solvents and combination of column chromatography on normal and reverse phases. The compounds with concentrations of 1000 and 5000 ppm were assessed against E. faecalis ATCC 29212 by agar well diffusion method, with chlorhexidine and fosfomycin being used as positive controls. Results: Two antibacterial compounds isolated from Sarang Semut were identified as two new flavonoids derivates of 1 (10 mg) and 2 (4 mg). Both compounds were tested for antibacterial activities against E. faecalis. MIC values of compounds 1 and 2 were 8.15 and 8.05 mm at 1000 ppm and 8.62 and 8.55 mm at 5000 ppm, respectively. MBC values were 156 and 625 ppm for 1 and 625 and 2500 ppm for 2, respectively. In an inhibitory murA enzyme activity assay, compounds 1 and 2 were shown to inhibit the enzyme activity by IC50 values of 21.7 and 151.3 ppm. Conclusion: The study demonstrated that ethyl acetate fraction of Sarang Semut contained antibacterial flavonoids as active constituents that showed activity against E. faecalis. These results showed the plant’s potential in herbal medicine and the development of new antibacterial agent for pathogenic dental caries.

Rebalance the oral microbiota as efficacy tool in endocrine, metabolic, and immune disorders

2020 ◽  
Vol 20 ◽  
Author(s):  
Ciro Gargiulo Isacco ◽  
Andrea Ballini ◽  
Danila De Vito ◽  
Kieu Cao Diem Nguyen ◽  
Stefania Cantore ◽  
...  
Keyword(s):  
Systemic Disease ◽  
Current Treatment ◽  
Oral Bacteria ◽  
The Body ◽  
Oral Microbiota ◽  
Oral Diseases ◽  
Philosophical Approach ◽  
Treatment And Prevention ◽  
Cardio Vascular Disease ◽  
Cardio Vascular

: The current treatment and prevention of oral disorders follow a very sectoral control and procedures considering mouth and its structures as system completely independent from the rest of the body. The main therapeutic approach is carried out on just to keep the levels of oral bacteria and hygiene in an acceptable range compatible with one-way vision of oral-mouth health completely separated from a systemic microbial homeostasis (eubiosis vs dysbiosis). This can negatively impact on the diagnosis of more complex systemic disease and its progression. Dysbiosis is consequence of oral and gut microbiota unbalance with consequences, as reported in current literature, in cardio vascular disease, diabetes mellitus, rheumatoid arthritis, and Alzheimer’s disease. Likewise, there is the need to highlight and develop a novel philosophical approach in the treatments for oral diseases that will necessarily involve non-conventional approaches.

scholarly journals In vitro activities of Acacia nilotica (L.) Delile bark fractions against Oral Bacteria, Glucosyltransferase and as antioxidant

2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Ali Mahmoud Muddathir ◽  
Ebtihal Abdalla M. Mohieldin ◽  
Tohru Mitsunaga
Keyword(s):  
Antioxidant Activity ◽  
Antibacterial Activity ◽  
Gallic Acid ◽  
Crude Extract ◽  
Inhibitory Activity ◽  
Oral Bacteria ◽  
Acacia Nilotica ◽  
Assay Method ◽  
Medicinal Uses ◽  
Wide Range

Abstract Background Dental caries and periodontal disease are the most common chronic infectious oral diseases in the world. Acacia nilotica was commonly known in Sudan as Garad or Sunt has a wide range of medicinal uses. In the present study, antibacterial activity of oral bacteria (Streptococcus sobrinus and Porphyromonas gingivalis), inhibitory activity against glucosyltransferase (GTF) enzyme and antioxidant activity were assayed for methanolic crude extract of A. nilotica bark and its fractions. Methods Methanoilc crude extract of A. nilotica bark was applied to a Sephadex LH-20 column and eluted with methanol, aqueous methanol, and finally aqueous acetone to obtain four fractions (Fr1- Fr4). Furthermore, the crude extract and fractions were subjected to analytical high performance liquid chromatography (HPLC). The crude extract and its fractions were assayed for antibacterial activity against S. sobrinus and P. gingivalis using a microplate dilution assay method to determine the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC), as well as GTF inhibition and antioxidant activity using ABTS radical scavenging method. Results Fractions (Fr1 and Fr2) exhibited MIC values of 0.3 mg/ml against the P. gingivalis. Additionally, Fr2 displayed MBC value of 1 mg/ml against two types of bacteria. Fr4 showed an especially potent GTF inhibitory activity with IC50 value of 3.9 μg/ml. Fr1 displayed the best antioxidant activity with IC50 value of 1.8 μg/ml. The main compound in Fr1 was identified as gallic acid, and Fr2 was mostly a mixture of gallic acid and methyl gallate. Conclusions The results obtained in this study provide some scientific rationale and justify the use of this plant for the treatment of dental diseases in traditional medicine. A. nilotica bark, besides their antibacterial potentiality and GTF inhibitory activity, it may be used as adjuvant antioxidants in mouthwashes. Further studies in the future are required to identify the rest of the active compounds.

scholarly journals Potential antibacterial and anti-halitosis activity of medicinal plants against oral bacteria

2020 ◽  
Vol 110 ◽  
pp. 104585 ◽  
Author(s):  
Dejanildo J. Veloso ◽  
Fariza Abrão ◽  
Carlos H.G. Martins ◽  
Juliana D. Bronzato ◽  
Brenda P.F.A. Gomes ◽  
...  
Keyword(s):  
Medicinal Plants ◽  
Oral Bacteria
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