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1.
Arch Oral Biol ; 110: 104601, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31734540

RESUMO

OBJECTIVES: Dental caries is the most common chronic infectious disease in children. Streptococcus mutans, the main cariogenic bacterial species, produces persisters, nongrowing dormant variants of regular cells associated with chronicity of diseases. We hypothesized that the recurrent nature of caries, particularly within populations with high-caries risk, is due partly to specific phenotypic features of S. mutans such as its ability to form persisters. We aimed to investigate the genotypic and phenotypic differences between the S. mutans from children with severe early-childhood caries (S-ECC) and those without caries. METHODS: S. mutans from plaque samples of caries-free (CF) and S-ECC children were tested for their ability to adapt to a lethal pH in an acid tolerance response assay. The persister levels of S. mutans isolates was quantified in both groups. RESULTS: S. mutanswas identified in all 23 S-ECC but only 6 of the 21 CF subjects. In most subjects, only one dominant S. mutans genotype was detected. No statistically significant differences in the mean survival percentage of S. mutans were observed between the two groups at a lethal pH of 3.5. However, the dominant genotype within a particular S-ECC subject exhibited a higher percentage of cell survival compared to those in the CF group. In S-ECC patients, S. mutans isolates displayed a ∼15-fold higher persistence phenotype than S. mutans isolates from CF patients. CONCLUSIONS: The ability of S. mutans to produce high levels of persisters may contribute to part of an individual's ability to control caries disease activity and recurrent lesions.


Assuntos
Cárie Dentária , Placa Dentária , Streptococcus mutans , Criança , Pré-Escolar , Cárie Dentária/microbiologia , Genótipo , Humanos , Fenótipo , Streptococcus mutans/genética , Streptococcus mutans/isolamento & purificação , Streptococcus mutans/patogenicidade
2.
Arch Oral Biol ; 110: 104617, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31794906

RESUMO

Streptococcus mutans and Candida albicans are the main oral pathogens which contribute to dental caries that affects all ages of human being. OBJECTIVES: This study focuses on the potential of crude cell free supernatant (CCFS) from lactic acid bacteria (LAB) to inhibit of the growth of S. mutans UKMCC 1019. DESIGN: A total of 61 CCFS from LAB strains were screened for their inhibitory ability against S. mutans UKMCC 1019 by broth microdilution method. The selected LAB with highest antimicrobial activity was identified and its CCFS was characterized for pH stability, temperature tolerance, enzyme sensitivity, metabolism of carbohydrates, enzymatic activities and antimicrobial activity against S. mutans UKMCC 1019 and C. albicans UKMCC 3001 by well diffusion assay. The effect of CCFS on cell structure of S. mutans UKMCC 1019 was observed under transmission electron microscopy (TEM). RESULTS: The CCFS from isolate CC2 from Kimchi showed the highest inhibition against S. mutans UKMCC 1019, which was 76.46 % or 4406.08 mm2/mL and it was identified to be most closely related to Enterococcus faecium DSM 20477 based on 16 s rRNA sequencing. The CCFS of E. faecium DSM 20477 had high tolerance to acidic and alkaline environment as well as high temperature. It also shows high antifungal activities against C. albicans UKMCC 3001 with 2362.56 mm2/mL. Under TEM, the cell walls and the cytoplasm membrane of S. mutans UKMCC 1019 were disrupted by the antimicrobial substance, causing cell lysis. CONCLUSIONS: Hence, the CCFS from E. faecium DSM 20477 is a potential bacteriocin in future for the treatment of dental caries.


Assuntos
Anti-Infecciosos , Cárie Dentária , Enterococcus faecium , Streptococcus mutans , Antibacterianos , Anti-Infecciosos/farmacologia , Biofilmes , Cárie Dentária/microbiologia , Enterococcus faecium/isolamento & purificação , Enterococcus faecium/fisiologia , Humanos , Streptococcus mutans/efeitos dos fármacos , Streptococcus mutans/patogenicidade
3.
Infect Immun ; 87(12)2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31527122

RESUMO

We previously demonstrated that recombinant protein PAc could be administered as an anticaries vaccine. However, the relatively weak immunogenicity of PAc limits its application. In the present study, we investigated the effect of two adjuvant combinations of chitosan plus Pam3CSK4 (chitosan-Pam3CSK4) and of chitosan plus monophosphoryl lipid A (chitosan-MPL) in the immune responses to the PAc protein in vivo and in vitro PAc-chitosan-Pam3CSK4 or PAc-chitosan-MPL promoted significantly higher PAc-specific antibody titers in serum and saliva, inhibited Streptococcus mutans colonization onto the tooth surfaces, and endowed better protection effect with significantly less caries activities than PAc alone. Chitosan-Pam3CSK4 and chitosan-MPL showed no statistically significant differences. In conclusion, our study demonstrated that the chitosan-Pam3CSK4 and chitosan-MPL combinations are promising for anticaries vaccine development.


Assuntos
Vacinas Bacterianas/imunologia , Quitosana/farmacologia , Cárie Dentária/prevenção & controle , Lipídeo A/análogos & derivados , Lipopeptídeos/farmacologia , Streptococcus mutans/imunologia , Adjuvantes Imunológicos , Animais , Cárie Dentária/microbiologia , Feminino , Imunogenicidade da Vacina/imunologia , Imunoglobulina A Secretora/análise , Lipídeo A/imunologia , Proteínas de Membrana/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Proteínas NLR/agonistas , Streptococcus mutans/patogenicidade , Receptores Toll-Like/agonistas , Vacinas Sintéticas/imunologia , Fatores de Virulência/imunologia
4.
Infect Immun ; 87(10)2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31383746

RESUMO

Candida albicans, a major opportunistic fungal pathogen, is frequently found together with Streptococcus mutans in dental biofilms associated with severe childhood caries (tooth decay), a prevalent pediatric oral disease. However, the impact of this cross-kingdom relationship on C. albicans remains largely uncharacterized. Here, we employed a novel quantitative proteomics approach in conjunction with transcriptomic profiling to unravel molecular pathways of C. albicans when cocultured with S. mutans in mixed biofilms. RNA sequencing and iTRAQ (isobaric tags for relative and absolute quantitation)-based quantitative proteomics revealed that C. albicans genes and proteins associated with carbohydrate metabolism were significantly enhanced, including sugar transport, aerobic respiration, pyruvate breakdown, and the glyoxylate cycle. Other C. albicans genes and proteins directly and indirectly related to cell morphogenesis and cell wall components such as mannan and glucan were also upregulated, indicating enhanced fungal activity in mixed-species biofilm. Further analyses revealed that S. mutans-derived exoenzyme glucosyltransferase B (GtfB), which binds to the fungal cell surface to promote coadhesion, can break down sucrose into glucose and fructose that can be readily metabolized by C. albicans, enhancing growth and acid production. Altogether, we identified key pathways used by C. albicans in the mixed biofilm, indicating an active fungal role in the sugar metabolism and environmental acidification (key virulence traits associated with caries onset) when interacting with S. mutans, and a new cross-feeding mechanism mediated by GtfB that enhances C. albicans carbohydrate utilization. In addition, we demonstrate that comprehensive transcriptomics and quantitative proteomics can be powerful tools to study microbial contributions which remain underexplored in cross-kingdom biofilms.


Assuntos
Biofilmes/crescimento & desenvolvimento , Candida albicans/genética , Regulação Bacteriana da Expressão Gênica , Regulação Fúngica da Expressão Gênica , Streptococcus mutans/genética , Transcriptoma , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Candida albicans/metabolismo , Candida albicans/patogenicidade , Metabolismo dos Carboidratos , Parede Celular/metabolismo , Criança , Técnicas de Cocultura , Cárie Dentária/microbiologia , Cárie Dentária/patologia , Glucanos/metabolismo , Glucosiltransferases/genética , Glucosiltransferases/metabolismo , Humanos , Proteômica , Streptococcus mutans/metabolismo , Streptococcus mutans/patogenicidade , Simbiose/genética
5.
Int J Mol Sci ; 20(14)2019 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-31315225

RESUMO

Cariogenic oral biofilms are strongly linked to dental caries around dental sealants. Quaternary ammonium monomers copolymerized with dental resin systems have been increasingly explored for modulation of biofilm growth. Here, we investigated the effect of dimethylaminohexadecyl methacrylate (DMAHDM) on the cariogenic pathogenicity of Streptococcus mutans (S. mutans) biofilms. DMAHDM at 5 mass% was incorporated into a parental formulation containing 20 mass% nanoparticles of amorphous calcium phosphate (NACP). S. mutans biofilms were grown on the formulations, and biofilm inhibition and virulence properties were assessed. The tolerances to acid stress and hydrogen peroxide stress were also evaluated. Our findings suggest that incorporating 5% DMAHDM into 20% NACP-containing sealants (1) imparts a detrimental biological effect on S. mutans by reducing colony-forming unit counts, metabolic activity and exopolysaccharide synthesis; and (2) reduces overall acid production and tolerance to oxygen stress, two major virulence factors of this microorganism. These results provide a perspective on the value of integrating bioactive restorative materials with traditional caries management approaches in clinical practice. Contact-killing strategies via dental materials aiming to prevent or at least reduce high numbers of cariogenic bacteria may be a promising approach to decrease caries in patients at high risk.


Assuntos
Antibacterianos/farmacologia , Biofilmes , Cimentos Dentários/química , Metacrilatos/farmacologia , Streptococcus mutans/efeitos dos fármacos , Ácidos/farmacologia , Antibacterianos/química , Fosfatos de Cálcio/química , Fosfatos de Cálcio/farmacologia , Peróxido de Hidrogênio/farmacologia , Metacrilatos/química , Streptococcus mutans/patogenicidade , Streptococcus mutans/fisiologia
6.
Dent Med Probl ; 56(2): 137-142, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31274251

RESUMO

BACKGROUND: It has been reported that patients with rheumatoid arthritis (RA) are more likely to exhibit periodontitis than patients without RA. However, the frequency and severity of dental caries in patients with RA is still unknown. OBJECTIVES: The aim of the study was to investigate whether higher counts of cariogenic bacteria are present in RA patients in contrast to healthy subjects, and to ascertain whether the frequency and severity of dental caries are increased in RA patients. MATERIAL AND METHODS: The study involved 160 adults: an RA group (n = 80) and a control group matched by age and gender (n = 80). The participants' dental status scores were determined based on the following indices: the Decayed, Missing and Filled Teeth (DMFT) index, the Filled and Sound Teeth (FS-T) index, Treatment Needs Index (TNI), Care Index (CI), and Integrative Dental Caries Index (IDCI). DNA copies of Streptococcus mutans (S. mutans) and Streptococcus sobrinus (S. sobrinus) were quantified using realtime polymerase chain reaction (PCR). RESULTS: The IDCI showed that the RA group was more affected, mainly presenting moderate to severe dental caries. The RA group also had higher global DMFT scores than the control group and scored higher on the decayed component of the DMFT index. The TNI and CI indicated that RA patients required more dental attention and appropriate treatment. The Streptococcus mutans count was significantly higher in the RA group. CONCLUSIONS: A complete basic oral examination, along with oral health instruction including adequate oral and dental hygiene, is crucial to prevent dental caries and associated complications in RA patients, since they appear to be more vulnerable than the non-RA population.


Assuntos
Artrite Reumatoide , Cárie Dentária , Placa Dentária , Adulto , Artrite Reumatoide/complicações , Cárie Dentária/complicações , Cárie Dentária/microbiologia , Humanos , Streptococcus mutans/isolamento & purificação , Streptococcus mutans/patogenicidade , Streptococcus sobrinus/isolamento & purificação , Streptococcus sobrinus/patogenicidade
7.
Arch Oral Biol ; 105: 52-58, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31276938

RESUMO

OBJECTIVE: To evaluate the potential of various alternative milk beverages to support bacterial biofilm formation and acid production and cause unbalanced demineralization. DESIGN: in vitro assays were used to examine the ability of the beverages to support Streptococcus mutans' biofilm formation and acid production from sugar fermentation and the capacity of the beverages to buffer pH changes. Biofilm formation was done using 96-well plate model. Acid production was measured using L-Lactate assay kit, and the buffering capacity was assessed by pH titration. For ex vivo caries model, enamel and dentine slabs and S. mutans biofilms were exposed to selected alternative milk beverages three times a day, 30 min each, and by the end of the experiments, slab's demineralization was assessed by loss of surface microhardness. RESULTS: Of the alternative milk beverages tested in this study, Original Almond consistently supported the most S. mutans biofilms, followed by Chocolate Cashew Milk, while the least biofilms were measured with Unsweetened Flax Milk. The most acids and the lowest culture pH were measured with Toasted Coconut Almond Milk, while the least buffering capacity was measured with Unsweetened Coconut Milk. The results of ex vivo caries model showed that like Bovine Whole Milk, repeated exposure to Original Almond led to significant enamel and dentine slab demineralization, when compared to those exposed to saline as a control (P < 0.001). CONCLUSIONS: These results further provide support that popular alternative milk beverages, especially those with supplemental sugars, are potentially cariogenic.


Assuntos
Biofilmes , Cárie Dentária/etiologia , Substitutos do Leite , Streptococcus mutans/patogenicidade , Desmineralização do Dente , Animais , Técnicas In Vitro , Sacarose
8.
Mol Oral Microbiol ; 34(5): 219-233, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31342653

RESUMO

Sortase A contributes to adhesion and biofilm formation of Streptococcus mutans by anchoring surface proteins like P1 onto the cell wall, and few other functional characterization has been annotated to this protein and its coding gene srtA. In this study we investigated that whether srtA deletion would affect S. mutans virulence determinants in addition to adhesion and further explored whether these effects were caused due to changes in S. mutans genomic transcription. We used acid-killing assays, glycolytic rate assessments, and exopolysaccharide (EPS) formation tests to detect whether srtA deletion influenced S. mutans acid tolerance/production and glucan formation. Comparisons between RNA-sequencing data from both the exponential and stationary phases of UA159 and the srtA-deleted strain were made to determine the impact of srtA knockout on S. mutans genomic transcription. Results of our assays indicated that S. mutans aciduricity was enhanced in the srtA deleted strain when bacterial cells were directly subjected to pH 2.8, but the enhancement was repressed when the acid tolerance response was induced in advance. The srtA mutation strain exhibited reduced EPS formation in mature biofilms. SrtA deletion led to pleiotropic changes in the S. mutans transcriptome with a growth phase-dependent pattern. The affected genes mainly included those involved in aciduricity, carbohydrate transport, and EPS formation. It was concluded that S. mutans srtA exhibited multiple effects on the virulence traits of this pathogen, including acid tolerance and glucan formation, and that these alterations could be partially due to transcriptional changes upon loss of srtA.


Assuntos
Aminoaciltransferases , Proteínas de Bactérias , Biofilmes , Cisteína Endopeptidases , Streptococcus mutans , Transcriptoma , Aminoaciltransferases/fisiologia , Proteínas de Bactérias/fisiologia , Cisteína Endopeptidases/fisiologia , Streptococcus mutans/patogenicidade , Virulência
9.
J Biotechnol ; 298: 57-63, 2019 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-30986518

RESUMO

Streptococcus mutans plays a key role in the development of dental caries and promotes the formation of oral biofilm produced by glucosyltransferases (GTFs). Bacillus velezensis K68 was isolated from traditional fermented foods and inhibits biofilm formation mediated by S. mutans. Gene amplification results demonstrated that B. velezensis K68 contained genes for the biosynthesis of 1-deoxynojirimycin (1-DNJ), a known GTF expression inhibitor. The presence of the GabT1, Yktc1, and GutB1 genes required for 1-DNJ synthesis in B. velezensis K68 was confirmed. Supernatant from B. velezensis K68 culture medium inhibited biofilm formation by 84% when S. mutans was cultured for 48 h, and inhibited it maximally when 1% glucose was added to the S. mutans culture medium as a GTF substrate. In addition, supernatant from B. velezensis K68 medium containing 3 ppb 1-DNJ decreased S. mutans cell surface hydrophobicity by 79.0 ± 0.8% compared with that of untreated control. The supernatant containing 1-DNJ decreased S. mutans adherence by 99.97% and 98.83% under sugar-dependent and sugar-independent conditions, respectively. S. mutans treated with the supernatant exhibited significantly reduced expression of the essential GTF genes gtfB, gtfC, and gtfD compared to that in the untreated group. Thus, B. velezensis inhibits biofilm formation, adhesion, and GTF gene expression of S. mutans through 1-DNJ production.


Assuntos
1-Desoxinojirimicina/metabolismo , Bacillus/metabolismo , Cárie Dentária/microbiologia , Streptococcus mutans/metabolismo , Proteínas de Bactérias/genética , Biofilmes/crescimento & desenvolvimento , Cárie Dentária/prevenção & controle , Regulação Bacteriana da Expressão Gênica , Glucosiltransferases/antagonistas & inibidores , Glucosiltransferases/genética , Humanos , Streptococcus mutans/patogenicidade
10.
Med Oral Patol Oral Cir Bucal ; 24(2): e211-e216, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30818314

RESUMO

BACKGROUND: The purpose of this study was to assess the association between chronic kidney diseases (CKD) and dental caries. MATERIAL AND METHODS: 107 patients with CKD and 107 with no systemic alteration were randomly included. DMFT (decayed, missing, and filled teeth), plaque index, colony-forming units (CFU) of Streptococcus mutans and salivary composition (IgA total, IgA anti- Streptococcus mutans, calcium and urea) were evaluated. McNemar and Wilcoxon tests were used to compare test and control groups. Spearman test was used to correlate time of hemodialysis and variables studied. Associations between variables were evaluated by logistic regression analysis. RESULTS: The number of filled teeth, the amount of IgA anti-Streptococcus mutans, salivary urea, education level, monthly income and the amount of CFU of Streptococcus mutans were statistically different between groups. There was a positive correlation between the duration of hemodialysis (Hd) and the amount of IgA anti-Streptococcus mutans, urea in saliva, and the number of CFU of Streptococcus mutans. In the adjusted model, a higher incidence of CFU mutans streptococci, elevated salivary urea, smaller number of filled teeth, lower DMFT, and less calcium salivary were associated with CKD. CONCLUSIONS: Programs to prevent and treat oral problems and regular follow-up at the beginning of dialysis are necessary to increase patients' awareness of their condition.


Assuntos
Cárie Dentária/complicações , Cárie Dentária/microbiologia , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/microbiologia , Streptococcus mutans/patogenicidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antibacterianos , Cálcio/análise , Estudos de Casos e Controles , Contagem de Colônia Microbiana , Estudos Transversais , Índice de Placa Dentária , Feminino , Humanos , Imunoglobulina A , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Saúde Bucal , Análise de Regressão , Diálise Renal/efeitos adversos , Saliva/química , Saliva/imunologia , Fatores Socioeconômicos , Streptococcus mutans/imunologia , Ureia/análise , Adulto Jovem
11.
Pediatr Dent ; 41(1): 56-62, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30803479

RESUMO

Purpose: The purpose of this study was to investigate the effects of polyphenol-rich cranberry extracts on dual-species Streptococcus mutans-Candida. albicans biofilms implicated in contributing to the severity of early childhood caries. Methods: S. mutans-C. albicans biofilms were grown on saliva-coated hydroxyapatite discs (s-HA) mounted on the high-throughput Amsterdam Active Attachment model. The s-HA discs were treated with the cranberry extracts/vehicle control for five minutes just before biofilm growth and subsequently, for similar exposure times, after 12 hours and 24 hours of biofilm growth. The treated 24-hour-old biofilms were then assessed for acidogenicity, metabolic activity, exopolysaccharide (EPS)/microbial biovolumes, structural organization, and colony forming unit (CFU) counts. Results: Treatment with 500 to 1,000 µg/mL of the cranberry extracts produced significant reductions in acidogenicity and metabolic activity (P<0.0001) compared to the control-treated biofilms. A significant decrease in biovolumes of the EPS (P=0.003) and microbial biofilm components (P=0.007) was also seen. Qualitative assessment of confocal biofilm images revealed that the cranberry extract disrupted biofilm structural architecture. Finally, significantly fewer S. mutans (P=0.006) and C. albicans (P=0.036) CFUs were recovered from the cranberry-treated biofilms than from the control-treated bio-films. Conclusions: Cranberry extracts inhibited cariogenic virulence properties of S. mutans-C. albicans dual-species biofilms in an in vitro model.


Assuntos
Biofilmes/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Cárie Dentária/prevenção & controle , Extratos Vegetais/farmacologia , Polifenóis/farmacologia , Streptococcus mutans/efeitos dos fármacos , Vaccinium macrocarpon , Candida albicans/patogenicidade , Criança , Frutas/química , Humanos , Testes de Sensibilidade Microbiana , Streptococcus mutans/patogenicidade , Vaccinium macrocarpon/química , Virulência/efeitos dos fármacos
12.
Microbiol Spectr ; 7(1)2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30657107

RESUMO

As a major etiological agent of human dental caries, Streptococcus mutans resides primarily in biofilms that form on the tooth surfaces, also known as dental plaque. In addition to caries, S. mutans is responsible for cases of infective endocarditis with a subset of strains being indirectly implicated with the onset of additional extraoral pathologies. During the past 4 decades, functional studies of S. mutans have focused on understanding the molecular mechanisms the organism employs to form robust biofilms on tooth surfaces, to rapidly metabolize a wide variety of carbohydrates obtained from the host diet, and to survive numerous (and frequent) environmental challenges encountered in oral biofilms. In these areas of research, S. mutans has served as a model organism for ground-breaking new discoveries that have, at times, challenged long-standing dogmas based on bacterial paradigms such as Escherichia coli and Bacillus subtilis. In addition to sections dedicated to carbohydrate metabolism, biofilm formation, and stress responses, this article discusses newer developments in S. mutans biology research, namely, how S. mutans interspecies and cross-kingdom interactions dictate the development and pathogenic potential of oral biofilms and how next-generation sequencing technologies have led to a much better understanding of the physiology and diversity of S. mutans as a species.


Assuntos
Biofilmes/crescimento & desenvolvimento , Cárie Dentária/microbiologia , Placa Dentária/microbiologia , Streptococcus mutans/fisiologia , Streptococcus mutans/patogenicidade , Metabolismo dos Carboidratos/fisiologia , Cárie Dentária/patologia , Placa Dentária/patologia , Humanos , Transdução de Sinais/fisiologia , Streptococcus mutans/metabolismo
13.
Caries Res ; 53(1): 84-95, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-29961075

RESUMO

Bisphenol A glycidyl methacrylate (bis-GMA), which is released into the oral environment by dental composites through incomplete polymerization, hydrolysis, and mechanical degradation, can significantly influence oral ecology around resin-based materials. The purpose of this study was to investigate how bis-GMA changes the virulence properties of Streptococcus mutans, a major cariogenic bacterium in humans. The results show that bis-GMA not only inhibited the planktonic growth of cells in medium containing glucose, fructose, or mannose, but also reduced the viability of S. mutans. However, the presence of bis-GMA increased sugar transport and intracellular polysaccharide accumulation in S. mutans, thereby increasing the potential of cell persistence. In addition, bis-GMA could enhance S. mutans's adhesion to hard surfaces and glucan synthesis, which could contribute to biofilm formation. Although free bis-GMA made cells vulnerable to acidic stress, it also provided increased resistance to hydrogen peroxide, which might confer an advantage in competition with other oral microorganisms during the early stage of biofilm development. Interestingly, the presence of bis-GMA did not change the ability of S. mutans to interact with saliva. The results suggest that leachable bis-GMA could contribute to biofilm-related secondary dental caries at the marginal interface between resin-based materials and teeth by altering the virulent properties of S. mutans, although bis-GMA reduced the planktonic growth and viability of S. mutans.


Assuntos
Biofilmes/efeitos dos fármacos , Bis-Fenol A-Glicidil Metacrilato/efeitos adversos , Cárie Dentária/etiologia , Teste de Materiais/métodos , Streptococcus mutans/efeitos dos fármacos , Streptococcus mutans/patogenicidade , Análise de Variância , Aderência Bacteriana/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cárie Dentária/microbiologia , Suscetibilidade à Cárie Dentária/efeitos dos fármacos , Glucosiltransferases/análise , Glicólise/efeitos dos fármacos , Humanos , Interações Hidrofóbicas e Hidrofílicas/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Saliva/química , Estatísticas não Paramétricas , Streptococcus mutans/fisiologia , Virulência/efeitos dos fármacos
14.
Indian J Dent Res ; 29(6): 760-767, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30589005

RESUMO

Background: Dental caries is a multifactorial disease in which microorganisms play an important role. Recently, herbs have been tried as mouthrinses to combat the side effects of chemical mouthrinses. The anticaries efficacy of Sodium fluoride, Tulsi leaf, and Black myrobalans fruit extracts on Streptococcus mutans (S. mutans) have been reported in the literature, but no comparative study has been done yet. Aim: This study aims to observe the change in the pH of saliva and to assess the efficacy of the herbal rinses-Tulsi and Black myrobalans on S. mutans count while comparing it with Sodium fluoride mouthrinse. Methods: Herbal ethanolic extracts of Tulsi (4%) and Black myrobalans (2.5%) were prepared as mouthrinses and compared with sodium fluoride mouthrinse (0.05%). Sixty high caries risk patients were selected and allocated randomly into three groups [n = 20], categorized as Group A-Sodium fluoride mouthrinse, Group B-Tulsi mouthrinse, and Group C-Black myrobalans mouthrinse. They were instructed to rinse their mouth with their assigned mouthrinses for 7 days. Salivary samples were collected and sent to the laboratory at baseline, 1 h postrinsing and after 7th day of rinsing for determining the salivary pH and S. mutans count. The increase in pH and reduction of S. mutans were determined. The values obtained were tabulated and statistically analyzed. Results: There was a significant increase in the salivary pH and reduction in S. mutans count after rinsing in all the three groups. Increase in salivary pH was more in the Sodium fluoride mouthrinse when compared to the experimental herbal groups (Group B and Group C). While S. mutans counts reduced more with Tulsi mouthrinse at 1 h postrinsing and after the 7th day of rinsing more reduction was seen in Black myrobalans mouthrinse group. Conclusion: The results of the study suggest that herbal mouthrinses could be tried as an adjunctive anticaries agent against dental caries causing microorganisms.


Assuntos
Cárie Dentária/prevenção & controle , Antissépticos Bucais/administração & dosagem , Ocimum sanctum , Extratos Vegetais/administração & dosagem , Saliva/química , Saliva/microbiologia , Fluoreto de Sódio/administração & dosagem , Streptococcus mutans/isolamento & purificação , Terminalia , Criança , Cárie Dentária/microbiologia , Feminino , Humanos , Concentração de Íons de Hidrogênio/efeitos dos fármacos , Masculino , Antissépticos Bucais/farmacologia , Extratos Vegetais/farmacologia , Fluoreto de Sódio/farmacologia , Streptococcus mutans/patogenicidade
15.
Biomed Res Int ; 2018: 2780948, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30519572

RESUMO

Dental caries are a process of demineralization and destruction of human teeth. They originate through many factors and are associated with biofilm formation, which consists of bacteria adhered to the teeth that form a structurally and functionally organized mass called dental plaque. Both the presence of Streptococcus mutans and the frequent consumption of sucrose correlate with a higher prevalence of caries in humans. In dogs, however, the incidence of this disease is low, due to factors such as differences in dental microbiota and/or their low consumption of sucrose. This work evaluated the antagonism of bacteria from dog's dental plaque against S. mutans, for the identification of producing strains of biotechnological products for use in preventing caries. This study used 95 bacterial isolates of canine dental plaque from the Veterinary Department at the Federal University of Viçosa, Minas Gerais, Brazil. A spot-on-the-lawn method was performed using Brain Heart Infusion agar with catalase for an initial identification of the antagonistic activity. Additional tests were conducted on the isolates classified as antagonists for confirmation of the activity, using modified Mann-Rogosa-Sharpe medium containing low dextrose concentration. These isolates were incubated at 37°C for 24 hours in anaerobiosis. The peptide nature of inhibition was evaluated using the following proteinases: proteinase K from Tritirachium album, bovine pancreatic trypsin, and type XII-A α-amylase from Bacillus licheniformis. In the initial identification of those strains exhibiting antimicrobial activity, 14 were classified as antagonists. One of the isolates (Bacillus sp.) indicated bacteriocinogenic activity, with a deformed inhibition halo on S. mutans by the addition of trypsin. These results suggest that this bacterial isolate may be applicable to biotechnological use to combat the main etiological agent of caries in humans. Further studies are needed to evaluate the bacteriocinogenic nature of the antimicrobial activities of the other 13 antagonistic bacterial isolates.


Assuntos
Bactérias/classificação , Cárie Dentária/microbiologia , Placa Dentária/microbiologia , Streptococcus mutans/patogenicidade , Animais , Antibacterianos/uso terapêutico , Bactérias/patogenicidade , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Brasil , Cárie Dentária/epidemiologia , Placa Dentária/epidemiologia , Cães , Humanos , Testes de Sensibilidade Microbiana , Microbiota/efeitos dos fármacos , Streptococcus mutans/genética , Streptococcus mutans/metabolismo , Sacarose/efeitos adversos
16.
Sci Rep ; 8(1): 16154, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30385826

RESUMO

Mature biofilms are highly resistant to antimicrobial agents due to the presence of extracellular polymeric substances (EPS), which inhibit the penetration of external molecules. In this study, we developed a coordination compound consisting of zinc chloride and erythritol that exhibits penetrating and bactericidal activity against Streptococcus mutans biofilms. An in vitro biofilm model was established in microplates, and bactericidal activity against biofilms was evaluated using an Alamar blue assay. The cause of the antimicrobial activity of the zinc-erythritol mixture on mature biofilms was demonstrated using fast atom bombardment-mass spectrometry, confocal laser scanning microscopy and atomic force microscopy. We demonstrated that zinc chloride spontaneously formed cationic complexes with erythritol in water. The zinc-erythritol complexes reduced intra- and inter-molecular interactions between bacterial exopolysaccharides, a major component of EPS. This activity was confirmed by measuring the attenuation of the hardness of dried polysaccharides isolated from S. mutans biofilms. The reduction in the interactions between polysaccharides allowed the complexes to penetrate into biofilms and kill the embedded bacteria. While approximately 13% of biofilm-associated microbes were killed by a 10 min treatment with 6.6 mM zinc chloride, 45% were killed when a solution containing 19.8 mM erythritol and 6.6 mM zinc chloride was used. This strategy of leveraging the coordination properties of metal ions with sugar alcohols provides a simple way to effectively remove mature biofilms using only conventional substances without the need for intricate chemical synthesis processes.


Assuntos
Anti-Infecciosos/farmacologia , Biofilmes/efeitos dos fármacos , Complexos de Coordenação/farmacologia , Streptococcus mutans/efeitos dos fármacos , Anti-Infecciosos/química , Complexos de Coordenação/química , Humanos , Microscopia Confocal , Polissacarídeos/química , Polissacarídeos/farmacologia , Streptococcus mutans/patogenicidade , Álcoois Açúcares/química , Álcoois Açúcares/farmacologia , Zinco/química , Zinco/farmacologia
17.
J Contemp Dent Pract ; 19(9): 1042-1046, 2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-30287701

RESUMO

AIM: The study aims to assess the Mentha piperita leaf extract's effectiveness against oral pathogens. MATERIALS AND METHODS: The leaf extract of M. piperita was prepared using cold water method. The three microbial strains, i.e., Streptococcus mutans, Aggregatibacter actinomycetem-comitans, and Candida albicans were used as microbiological materials. Chlorhexidine 0.2% was used as positive control. The digital caliper was used to measure the zone of inhibition to know the antimicrobial activity at 24 and 48 hours. To compare the activity within and between the different microbial strains, one-way analysis of variance (ANOVA) was used. To analyze the data, Statistical Package for the Social Sciences (SPSS) software version of 21.0 was used. The p-value ≤0.05 was considered as statistically significant. RESULTS: Maximum inhibition zone was seen in both M. piperita extracts and 0.2% chlorhexidine with S. mutans at 24 and 48 hours, followed by A. actinomycetemcomitans, and C. albi-cans respectively. The statistical analysis ANOVA reveals the statistically significant association of M. piperita extracts with p-value <0.001. The comparison with 0.2% chlorhexidine at 24 hours showed a p-value of <0.04 and at 48 hours, it showed a p-value <0.001, which was statistically significant. CONCLUSION: The present study concluded that M. piperita showed antimicrobial activity against the oral microorganisms which are causing major less or more severe oral diseases and it can be administered as an alternative medicine for the conventional treatment. CLINICAL SIGNIFICANCE: The study results serve as a guide in selecting and providing information about the efficacy of M. piperita extracts to the dental professionals. The discovery of a potential herbal medication would be a great development in the field of antimicrobial therapies.


Assuntos
Aggregatibacter actinomycetemcomitans/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Mentha piperita/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Streptococcus mutans/efeitos dos fármacos , Aggregatibacter actinomycetemcomitans/patogenicidade , Candida albicans/patogenicidade , Candidíase Bucal/microbiologia , Farmacorresistência Bacteriana , Farmacorresistência Fúngica , Humanos , Testes de Sensibilidade Microbiana/métodos , Estomatite/microbiologia , Streptococcus mutans/patogenicidade
18.
Mol Oral Microbiol ; 33(6): 440-449, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30329221

RESUMO

Streptococcus mutans is the primary etiological agent of human dental caries. Its major virulence factors, glucosyltransferases (Gtfs), utilize sucrose to synthesize extracellular polysaccharides (EPS), leading to the formation of dental plaque biofilm. The current study was designed to develop a novel self-targeting gene editing technology that targeted gtfs to inhibit biofilms formation. The CRISPR-Cas system (ie, clustered regularly interspaced short palindromic repeat, with CRISPR-associated proteins) provides sequence-specific protection against foreign genetic materials in archaea and bacteria, and has been widely developed for genomic engineering. The first aim of this study was to test whether components of the CRISPR-Cas9 system from S mutans UA159 is necessary to defend against foreign DNA. The data showed that a suitable PAM site, tracrRNA, Cas9, and RNase III are indispensable elements to perform normal function of S mutans CRISPR-Cas9 system. Based on these results, we designed self-targeting CRISPR arrays (containing spacer sequences identifying with gtfB) and cloned them onto plasmids. Afterward, we transformed the plasmids and editing templates into UA159 (self-targeting) to acquire desired mutants. Our data showed that this technology performed well and was able to successfully edit gtfB or gtfBgtfC genes. This resulted in high reduction in EPS synthesis and was able to breakdown biofilm formation, which is also a promising tool for dental clinics in order to prevent the formation of S mutans biofilms in the future.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes/métodos , Streptococcus mutans/genética , Biofilmes/crescimento & desenvolvimento , Cárie Dentária/microbiologia , Placa Dentária/microbiologia , Glucosiltransferases/genética , Humanos , Microscopia Eletrônica de Varredura , Streptococcus mutans/patogenicidade , Fatores de Virulência/genética
19.
J Bacteriol ; 200(23)2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30201780

RESUMO

Cnm is a surface-associated protein present in a subset of Streptococcus mutans strains that mediates binding to extracellular matrices, intracellular invasion, and virulence. Here, we showed that cnm transcription is controlled by the global regulators CovR and VicRKX. In silico analysis identified multiple putative CovR- and VicR-binding motifs in the regulatory region of cnm as well as in the downstream gene pgfS, which is associated with the posttranslational modification of Cnm. Electrophoretic mobility shift assays revealed that CovR and VicR specifically and independently bind to the cnm and pgfS promoter regions. Quantitative real-time PCR and Western blot analyses of ΔcovR and ΔvicK strains as well as of a strain overexpressing vicRKX revealed that CovR functions as a positive regulator of cnm, whereas VicRKX acts as a negative regulator. In agreement with the role of VicRKX as a repressor, the ΔvicK strain showed enhanced binding to collagen and laminin and higher intracellular invasion rates. Overexpression of vicRKX was associated with decreased rates of intracellular invasion but did not affect collagen or lamin binding activities, suggesting that this system controls additional genes involved in binding to these extracellular matrix proteins. As expected, based on the role of CovR in cnm regulation, the ΔcovR strain showed decreased intracellular invasion rates, but, unexpectedly collagen and laminin binding activities were increased in this mutant strain. Collectively, the results presented here expand the repertoire of virulence-related genes regulated by CovR and VicRKX to include the core gene pgfS and the noncore gene cnm IMPORTANCE Streptococcus mutans is a major pathogen associated with dental caries and also implicated in systemic infections, in particular, infective endocarditis. The Cnm adhesin of S. mutans is an important virulence factor associated with systemic infections and caries severity. Despite its role in virulence, the regulatory mechanisms governing cnm expression are poorly understood. Here, we describe the identification of two independent regulatory systems controlling the transcription of cnm and the downstream pgfS-pgfM1-pgfE-pgfM2 operon. A better understanding of the mechanisms controlling expression of virulence factors like Cnm can facilitate the development of new strategies to treat bacterial infections.


Assuntos
Adesinas Bacterianas/metabolismo , Proteínas de Transporte/metabolismo , Cárie Dentária/microbiologia , Endocardite/microbiologia , Regulação Bacteriana da Expressão Gênica/genética , Processamento de Proteína Pós-Traducional , Infecções Estreptocócicas/microbiologia , Streptococcus mutans/genética , Adesinas Bacterianas/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Proteínas de Transporte/genética , Colágeno/metabolismo , Matriz Extracelular/genética , Matriz Extracelular/metabolismo , Humanos , Óperon/genética , Ligação Proteica , Streptococcus mutans/metabolismo , Streptococcus mutans/patogenicidade , Virulência , Fatores de Virulência/genética , Fatores de Virulência/metabolismo
20.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 36(4): 360-366, 2018 Aug 01.
Artigo em Chinês | MEDLINE | ID: mdl-30182561

RESUMO

OBJECTIVE: This study intends to explore the mechanism underlying the support of sortase A (SrtA) of the cariogenicity of Streptococcus mutans (S. mutans). METHODS: We performed a metabonomics study based on ¹H nuclear magnetic resonance spectroscopy (NMR), in which we compared the extracellular metabolites of wild-type S. mutans UA159 with those of its SrtA-deficient strain. Metabolite differences among strains were identified using a combination of principal component analysis and orthogonality partial least square discriminant analysis. RESULTS: Several differences corresponding mostly to unknown metabolites were identified. Some amino acids such as leucine and valine (δ 0.92×10⁻6-1.20×10⁻6), lactic acid ( δ1.28×10⁻6), oxoglutaric acid (δ 3.00×10⁻6), and glycine (δ 3.60×10⁻6) differed among strains. CONCLUSIONS: This work establishes the feasibility of using ¹H NMR-based metabonomics to provide leads for research into molecular factors that promote caries. The database of microbial metabolites should be also improved in further studies.


Assuntos
Aminoaciltransferases , Proteínas de Bactérias , Cisteína Endopeptidases , Metabolômica , Streptococcus mutans , Aminoaciltransferases/metabolismo , Proteínas de Bactérias/metabolismo , Cisteína Endopeptidases/metabolismo , Streptococcus mutans/patogenicidade
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