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PubMed1977

Infective endocarditis caused by Streptococcus mutans. A complication of idiopathic hypertrophic subaortic stenosis.

Three patients with endocarditis caused by Streptococcus mutans were seen during a six-month period. All had clinical features of subacute bacterial endocarditis, including fever, heart murmurs, and positive blood cultures. One had underlying aortic insufficiency and two had idiopathic hypertrophic subaortic stenosis. All patients were treated with parenteral antibiotics and were cured. Streptococcus mutans is a pleomorphic, microaerophilic organism that is associated with dental caries and plaque. Differentiation of S mutans from enterococcal endocarditis is important because the former condition can be treated for a shorter period of time with penicillin alone, without the addition of aminoglycoside antibiotics.

Cardiomyopathy, Hypertrophic↗

PubMed2001

[Effect of sodium fluoride mouth rinses containing xylitol and sorbitol on the number of Streptococcus mutans from human saliva].

The objective of this study was to assess the effect of 0.05% sodium fluoride solutions containing 2.5% or 12.5% xylitol on the number of Streptococcus mutans in the human mouth. Fifty boys between 8 and 16 years of age participated in this double-blind crossover study. Of the original 50 boys, 33 finished the study. Participants were randomly divided into four groups. The following solutions were employed: placebo solution; 0.05% sodium fluoride solution; 0.05% sodium fluoride + 2.5% xylitol + 2% sorbitol; 0.05% sodium fluoride + 12.5% xylitol + 2% sorbitol. Each solution was used for a 28-day period (20 mL/day, twice a day), with a 10-day washout period between solutions. There were no significant differences (P = 0.32) between the two xylitol-containing solutions (2.5% vs. 12.5%) concerning the number of Streptococcus mutans. However, there was a significant difference between these two xylitol-containing solutions and the sodium fluoride and placebo solutions (P < 0.001). Our results suggest that the 0.05% sodium fluoride solutions containing either 2.5% or 12.5% xylitol caused a significant reduction in the number of Streptococcus mutans.

Adolescent↗

PubMed1982

Streptococcus mutans in plaque and saliva after mouthrinsing with SnF2.

Mouthrinses with SnF2 in 11 subjects significantly reduced (P less than 0.01) the total colony forming units (CFU) count and the numbers of Streptococcus mutans and Streptococcus sanguis in plaque. The numbers of S. mutans and S. sanguis were significantly more reduced than was the total CFU count. After rinsing with SnF2S. sanguis was present in 97% and S. mutans in only 42% of plaque samples from tooth surfaces where they were detected after rinsing with water. SnF2 also significantly reduced (P less than 0.01) the number of S. mutans in saliva. Mouthrinses with NaF did not markedly affect the number of S. mutans either in plaque or in saliva.

Dental Plaque↗

PubMed2003

Suppression of salivary Streptococcus mutans and lactobacilli by topical caries preventive agents.

Reduction of cariogenic bacteria, especially salivary Streptococcus mutans and lactobacilli is a valuable clinical procedure that in many ways alleviates implementation of targeted caries preventive procedures in the entire population. The aim of this study was to investigate the caries preventive values of certain preventive procedures in in vivo conditions. Four groups of subjects, each with 18 children aged from 4-5 and 10-12 years (n = 72) were treated with different caries preventive agent (aminfluoride solution, Proxyt paste, chewing gum containing xylitol and fluoride and chlorhexidine solution). During a period of two months five control measurements for number of salivary Streptococcus mutans (SM) and lactobacilli (LB) were performed. At the end of the study the best result in the reduction of the bacteria was achieved by the application of Proxyt paste and daily use of chewing gum (p < 0.001). In patients treated with this preventive procedure the number of SM was reduced by 1 class and LB to < 10(4) CFU/ml saliva after two months of study. The results obtained indicate that professional teeth cleaning and use of chewing gum with xylitol and fluorides on daily basis can be very effective protocol for cariogenic bacteria reduction and in the individual caries prevention.

Administration, Topical↗

PubMed1986

Calcium modulation of growth of Streptococcus mutans.

The steady-state growth yield of Streptococcus mutans (in a Teflon chemostat using a chemically defined medium that was treated to lower trace metal contamination and supplemented with high-purity trace metals) was doubled by addition of 0.63 microM calcium. Subsequent increases in calcium concentration to 1.3 microM and 2.5 microM lowered steady-state growth yield below the level with no added calcium, suggesting that calcium has dose-dependent stimulatory and inhibitory effects on S. mutans.

Calcium↗

PubMed2001

[Effect of para-aminobenzoic acid on the adhesion of Streptococcus mutans].

OBJECTIVE: To investigate the effects of Para-aminobenzoic acid (PABA) on the adhesion of Streptococcus mutans to saliva-coated hydroxyapatite (S-HA). METHODS: The adhesion model in vitro established by Gibbons was adopted in this study to quantify adsorptive cells through [3H] thymidine labelling. RESULTS: PABA solution over a range of concentration from 10(-9) to 10(-3) g/L could inhibit the attachment of S. mutans to S-HA effectively, and the inhibition declined when the concentration of PABA solution was 10(-3) g/L. CONCLUSION: PABA can inhibit the adherence of Streptococcus mutans to S-HA effectively.

4-Aminobenzoic Acid↗

PubMed2000

[In vitro study of Streptococcus mutans in the plaque on the surface of amalgam fillings on the conversion of inorganic mercury to organic mercury].

OBJECTIVE: To study the Streptococcus mutans in the plaque on the surface of amalgam fillings on the conversion of inorganic mercury to organic mercury. METHODS: Plaque was sampled from the amalgam restorations after amalgam filling regularly, serving the unfilled tooth as control. Streptococcus mutans was identified and inoculated to 10 ml TSB. After incubated 24 hours, mercury in water was added to the concentration of 100 ng/ml, incubated 24 hours again, the concentration of inorganic and organic mercury was determined. RESULTS: It was found that the difference of organic mercury and organic mercury between the baseline and the times after amalgam filling in test group and control was significant, while the difference between the times after amalgam filling was not significant, and the difference between the test group and the control was not significant, either. CONCLUSION: Streptococcus mutans can convert inorganic mercury to organic mercury in some way, and the mercury of amalgam plays some role in it.

English Abstract↗

PubMed2006

Inhibitory effects of cranberry polyphenols on formation and acidogenicity of Streptococcus mutans biofilms.

Cranberry fruit is a rich source of polyphenols, and has shown biological activities against Streptococcus mutans. In the present study, we examined the influence of extracts of flavonols (FLAV), anthocyanins (A) and proanthocyanidins (PAC) from cranberry on virulence factors involved in Streptococcus mutans biofilm development and acidogenicity. PAC and FLAV, alone or in combination, inhibited the surface-adsorbed glucosyltransferases and F-ATPases activities, and the acid production by S. mutans cells. Furthermore, biofilm development and acidogenicity were significantly affected by topical applications of PAC and FLAV (P<0.05). Anthocyanins were devoid of any significant biological effects. The flavonols are comprised of mostly quercetin glycosides, and the PAC are largely A-type oligomers of epicatechin. Our data show that proanthocyanidins and flavonols are the active constituents of cranberry against S. mutans.

Anthocyanins↗

PubMed2006

Effect of coating the wells of a polystyrene microtiter plate with xanthorrhizol on the biofilm formation of Streptococcus mutans.

Colonization on the surface of tooth by Streptococcus mutans is an important step in the initiation of dental plaque. Polystyrene microtiter plates have been employed to study bacterial colonization and biofilm formation of periodontal bacteria. The objective of this work was to evaluate the effect of coating the wells of a polystyrene microtiter plate with xanthorrhizol isolated from java turmeric (Curcuma xanthorrhiza Roxb.) on Strep. mutans biofilm formation. Our studies demonstrated that coating of a polystyrene microtiter plate with 5 microg/ml of xanthorrhizol resulted in significant (up to 60%) reduction of adherent cells compared to that of cells in uncoated wells. This result suggests that xanthorrhizol displays potent activity in preventing Strep. mutans biofilm formation.

Animals↗

PubMed1979

Electron microscopy and immunoperoxidase staining of Streptococcus mutans during controlled growth in two different media.

Streptococcus mutans subspecies sobrinus serotype d (B13) was cultivated in a fermentor under controlled conditions in two different media: a complex proteose-peptone medium and a defined minimal medium (C4). Specimens from different growth phases were examined by electron-microscopy and tested electron-immunohistochemically. Irrespective of the growth medium used, no differences were observed in the immunohistochemical staining pattern of bacteria during the lag, the exponential and the early staionary phases. Specimens obtained several hours after exponential growth contained areas where the bacteria showed staining that ranged from a strong deposit of reaction product to no deposit. This appearance seems partly to explain the differences in the intensity of immunohistochemical staining of certain bacteria observed in dental plaques stained for identification of S. mutans subspecies sorbrinus.

Bacteriological Techniques↗

PubMed1992

Molecular analysis of a Streptococcus mutans strain exhibiting polymorphism in the tandem gtfB and gtfC genes.

Streptococcus mutans UA101, which was previously demonstrated to be highly cariogenic in gnotobiotic rats, exhibited much lower water-insoluble glucan (IG) synthetic activity compared with that of S. mutans GS5 and was unable to express sucrose-dependent colonization of smooth surfaces in vitro. On the basis of Southern and Western blot (immunoblot) analyses, it was demonstrated that, unlike most S. mutans strains, strain UA101 contained a single copy of a gene coding for IG synthesis. The gene was isolated from a clone bank constructed with the plasmid pTH10 clone bank in Escherichia coli and had apparently evolved after homologous recombination of the gtfB and gtfC genes present on the chromosome of a recent ancestor of strain UA101. The enzyme expressed from the gene, gtfBC, was purified to near homogeneity by utilizing a single-step preparative sodium dodecyl sulfate-polyacrylamide gel electrophoresis system and was characterized. A derivative of strain UA101, UA101LBS, containing a chromosomal insertion of the GS5 gtfC gene was constructed after transformation. UA101LBS exhibited high IG synthetic activity and colonized smooth surfaces in vitro. By utilizing a conventional rat model system involving animals fed a high-sucrose diet, strain UA101 exhibited low levels of smooth surface caries activity relative to Streptococcus sobrinus 6715. By contrast, UA101LBS was as cariogenic as strain 6715. However, sulcal caries occurred equally well with all of the strains tested. These results are evaluated relative to the role of gtf gene products in cariogenicity.

Animals↗

PubMed1986

Properties of mutacin b, an antibacterial substance produced by Streptococcus mutans strain BHT.

An antibacterial substance produced by strain BHT of Streptococcus mutans (mutacin b) was found to be a small molecule (MW 3,500-6,000) with remarkable resistance to temperature, alkali and various solvents. Enzyme sensitivity tests of partially purified preparations indicated that mutacin b is a peptide. It is sensitive to several proteolytic enzymes and its lethal effects on sensitive cells can be prevented by adding trypsin to cells exposed to mutacin b. High concentrations of mutacin b inhibited the growth of producer cells, indicating that strain BHT is only partially immune to this substance.

Bacteriocins↗

PubMed1977

Recovery of Streptococcus mutans after amino acid deprivation.

The recovery of Streptococcus mutans FA-1 in a complete, chemically defined medium was examined after 1, 3, and 6 h of essential amino acid deprivation. Amino acids could be divided into two groups based on their effect on the relative rates of recovery: those amino acids (leucine and cystine) that are precursors of protein only, and amino acids (glutamate/glutamine or lysine) that are incorporated into both protein and cell wall peptidoglycan. Culture turbidity, deoxyribonucleic acid, ribonucleic acid, protein and cell wall peptidoglycan measurements indicated rapid recovery after leucine/cystine starvation periods. However, a 6-h leucine/cystine deprivation resulted in a slower exponential rate of growth (180-min doubling time compared to the normal doubling time of 85 to 90 min) after recovery. Glutamate/glutamine starvation, on the contrary, resulted in greatly extended recovery periods, especially after 3- and 6-h amino acid deprivations. Macromolecular synthesis was most severely affected by 6-h glutamate/glutamine starvation and required 6 to 10 h for recovery of an exponential rate. A delay in the recovery of deoxyribonucleic acid and cell wall peptidoglycan synthesis beyond that of the other macromolecules was observed after 1 and 3 h of deprivation with either leucine/cystine or glutamate/glutamine. However, after a 6-h amino acid deprivation, deoxyribonucleic acid synthesis recovered more rapidly than that of the other macromolecules studied. The results are discussed in terms of the nutritional environment of the oral cavity and its effect on the growth and survival of S. mutans.

Amino Acids↗

PubMed1995

Evaluation of the automicrobic system for the identification of Streptococcus mutans.

The performance of the Automicrobic System with the Vitek gram-positive identification card (bioMérieux, France) in identifying strains of Streptococcus mutans was studied. Of 160 strains assayed, 72.5% were confirmed to be Streptococcus mutans; the remainder were identified as other species of streptocci (Streptococcus bovis, Streptococcus uberis, Streptococcus anginosus, Streptococcus sanguis I and II, Streptococcus intermedius, and Streptococcus constellatus).

Bacterial Typing Techniques↗

PubMed1976

Properties of a mutant of Streptococcus mutans altered in glucosyltransferase activity.

A mutant of Streptococcus mutans GS-5 has been isolated as a smooth colonial variant on mitis salivarius agar. This mutant, designated SNG-1, adheres to glass surfaces as well as the parental organism when grown in the presence of sucrose. However, in contrast to the parental organism, glucose-grown cultures of the mutant did not adhere to smooth surfaces when incubated with sucrose under nongrowing conditions. The inability of the mutant organism to adhere to glass surfaces under the latter condition was a result to markedly reduced levels of mutant cell-associated glucosyltransferase activity. In addition, the extracellular activity of the mutant was also severely depressed relative to the parental activity. The reduced levels of mutant enzyme activity appear to be a result of a mutation in a structural gene coding for glucosyltransferase activity since (i) mutant glucosyltransferase activity is much less resistant to heat inactivation compared to the parental enzymes and (ii) the migration patterns of the mutant and parental enzymes differ on polyacrylamide gels and after isoelectric focusing on polyacrylamide gels. However, the kinetic properties of the mutant enzymes are similar to those of the comparable parental activities in terms of pH and temperature optima and Km values for sucrose. The mutant enzyme responsible for soluble glucan synthesis has been purified approximately 300-fold. These results are discussed in terms of the mechanism of glucan synthesis by S. mutans.

Binding Sites↗

PubMed1995

Effect of an antibacterial varnish and amine-fluoride/stannous fluoride (AmF/SnF2) toothpaste on Streptococcus mutans counts in saliva and dental plaque of children.

The purpose of this study was to evaluate the effect of the simultaneous application of a chlorhexidine and thymol-containing varnish (Cervitec) and an amine fluoride/stannous fluoride containing toothpaste (Meridol) on Streptococcus mutans counts in saliva and dental plaque of school children 12-14 years of age, during a six-week period. The children were separated into group 1 (Cervitec varnish + fluoride-containing toothpaste), group 2 (Cervitec varnish + Meridol toothpaste), and group 3 (Meridol toothpaste alone). Over the six weeks the greatest improvement in salivary Streptococcus mutans count occurred in group 2. Overall, a statistically significant decrease in total microbiological count, and Streptococcus mutans was found in all three groups.

Adolescent↗

PubMed1986

Isolation and characterization of a fructosyltransferase gene from Streptococcus mutans GS-5.

A fructosyltransferase (FTF) gene from Streptococcus mutans GS-5 has been isolated from a lambda L47.1 clone bank. The gene was contained on an 11.7-kilobase GS-5 DNA fragment and was initially subcloned into plasmid pACYC184 as a 5.4-kilobase HindIII fragment. However, further analysis revealed that transcription of the FTF gene was initiated at the P1 promoter contained on the vector. It was possible to subclone the FTF gene with its presumed promoter as a 3.4-kilobase EcoRI fragment to produce the chimeric plasmid pSS22 expressing FTF activity. The cloned enzyme was purified to apparent homogeneity after ammonium sulfate precipitation, gel filtration, and DEAE-Bio-Gel-A chromatography followed by preparative sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The purified enzyme displayed a lower molecular weight (63,000) compared with the multiple activities detected in the culture fluids of strain GS-5. In addition, storage of the purified enzyme resulted in the formation of even lower-molecular-weight enzymatically active species. These results suggested that proteolytic degradation of the FTF occurs both in S. mutans and in Escherichia coli. In addition, a comparison of the properties of the cloned enzyme with those previously characterized from another serotype c S. mutans strain suggests that multiple FTF genes may be present in these organisms.

Cell Compartmentation↗

PubMed1989

Evaluation of antimicrobial activity in vitro of ten root canal sealers on Streptococcus sanguis and Streptococcus mutans.

The antimicrobial activity of ten root canal sealers was studied on Streptococcus sanguis and Streptococcus mutans. One hundred plates of trypticase soy agar-sheep red blood cell (10%), each with four distinct 3 mm diameter wells, were divided into two groups of 50 by means of the Lawn technique; one group was inoculated with S. sanguis and the other with S. mutans. Four milligrams of each root canal sealer was placed in each of three wells in 10 plates (five plates of each inoculant); the fourth well was left empty as a control site. Plates were incubated at 37 degrees C and checked after 2, 7, and 14 days. All root canal sealers inhibited growth of both organisms. The inhibitory zones for S. sanguis were larger than inhibitory zones for S. mutans for all tested sealers, except Diaket. Dentinol, Kerr, and Tubliseal had significantly more inhibitory effect on S. sanguis than did other tested sealers (p less than 0.05). Diaket had superior inhibition on S. mutans.

Bismuth↗