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PubMed1978

Salivary IgA antibodies to antigens from Streptococcus mutans in human dental caries.

1) Subjects of low caries experience (DMF 7) had significantly lower IgA antibody titers to antigens from S. mutans serotype c than subjects of high caries experience (DMF 13). 2) Subjects with carious lesions and a high DMF had significantly lower salivary antibody titers than subjects without carious lesions. 3) Sequential studies revealed that in the absence of caries salivary antibody titers decreased over a 9 month period. 4) Treatment of caries was associated with a rise in salivary IgA antibodies. No significant changes were associated with the development of caries. 5) No relationship with caries experience was found with antibodies to S. mutans BHT (serotype b), S. sanguis OMZ-9 or S. mitis CHT. 6) The results do not support the hypothesis that salivary antibodies in man play a role in protection against caries.

Antibodies, Bacterial↗

PubMed1980

Interaction of parotid saliva basic glycoprotein with Streptococcus sanguis ATCC 10557.

It is postulated that an initial step in dental plaque formation is the adherence of oral bacteria to the salivary pellicle. Recently, we have found that a proline-rich and basic glycoprotein (MGP) from human parotid saliva, which is successfully purified by Concanavalin A-Sepharose affinity chromatography, binds to some oral streptococci such as S. mitis and S. sanguis. This paper deals with some inhibitors which affect the binding of the MGP to S. sanguis ATCC 10557. The assay for the binding ability of the radioactive MGP to the bacterial cells was performed by incubation of the reaction mixture containing 10 microgram of [3H]MGP (6000 dpm) and about 4.5 mg of bacterial cells (dry weight) in 0.5 ml of 0.05 M Tris-HCl buffer containing 0.05 M NaCl, pH 8.0 with a final volume of 0.51 ml. After 1 hour standing at 4 degrees C, the cells were washed five times with the same buffer. The resulting sediment was solubilized in 0.5 ml of NCS tissue solubilizer and the radioactivity was measured. The binding of the radioactive MGP to bacterial cells was specifically inhibited by galactose, lactose and N-acetyllactosamine. Applications of heat and trypsin on the cell surface, strikingly reduced the binding ability. These findings strongly suggested that a lectin-like substance may be present on the bacterial cell surface.

Adult↗

PubMed1982

Comparison of computer methods for taxonomy of some streptococci using gas chromatographic chemotaxonomic data.

Gas chromatographic fingerprints of eighty-three strains of Streptococcus were analysed by computer. Seven measures of association were compared for their ability to identify strains. The most effective measure was the Stack coefficient which correctly identified 68% of strains, mostly of oral origin. Clustering of strains was carried out by median, average, single-linkage, furthest neighbour, and centroid linkage, Andrew's plots, and Minimum Spanning Trees. Of the clustering methods, centroid linkage produced the most inclusive and compact clusters. Clusters of strains of S. mitis, S. mutans, S. salivarius and S. sanguis showed varying degrees of heterogeneity; while, S. milleri was comprised of three chemotypes corresponding to oral isolates, biochemically atypical vaginal isolates, and biochemically typical strains from other sources.

Chromatography, Gas↗

PubMed2005

Identification of 43 Streptococcus species by pyrosequencing analysis of the rnpB gene.

Pyrosequencing technology was evaluated for identification of species within the Streptococcus genus. Two variable regions in the rnpB gene, which encodes the RNA subunit of endonuclease P, were sequenced in two reactions. Of 43 species, all could be identified to the species level except strains of the species pairs Streptococcus anginosus/S. constellatus and S. infantis/S. peroris. A total of 113 blood culture isolates were identified by pyrosequencing analysis of partial rnpB sequences. All but eight isolates could be unambiguously assigned to a specific species when the first 30 nucleotides of the two regions were compared to an rnpB database comprising 107 streptococcal strains. Principal coordinate analysis of sequence variation of strains from viridans group streptococci resulted in species-specific clusters for the mitis and the salivarius groups but not for the anginosus group. The identification capacity of pyrosequencing was compared to the biochemical test systems VITEK 2 and Rapid ID 32 Strep. The concordance between pyrosequencing and VITEK 2 was 75%, and for Rapid ID 32 Strep the corresponding figure was 77%. Isolates with discrepant identifications in the three methods were subjected to entire rnpB DNA sequence analysis that confirmed the identifications by pyrosequencing. In conclusion, pyrosequencing analysis of the rnpB gene can reliably identify Streptococcus species with high resolution.

Bacterial Typing Techniques↗

PubMed1990

Platelet aggregation by oral streptococci.

One proposed mechanism in the pathogenesis of infective endocarditis is the direct aggregation of platelets by the bacteria causing the disease. Some, but not all, strains of Streptococcus sanguis have been reported to aggregate platelets but the taxonomy of this and related taxa has changed recently. The ability to aggregate platelets by 24 genetically grouped laboratory stock strains was studied along with 8 recent isolates from cases of endocarditis. Strains belonging to S. sanguis could aggregate platelets, but not S. gordonii, "S. parasanguis", S. mitis, S. oralis or related taxa. Also, preliminary data indicate that certain biotypes of S. sanguis lack the ability to aggregate platelets. Of the recent clinical isolates, only 4 aggregated platelets and each of these showed phenotypes typical of S. sanguis. These data suggest that the ability to aggregate platelets is not essential for an organism to be able to cause endocarditis, although it may be a significant virulence factor.

Humans↗

PubMed2006

A lacticin 3147 enriched food ingredient reduces Streptococcus mutans isolated from the human oral cavity in saliva.

AIMS: To isolate and characterise Streptococcus mutans from Irish saliva samples and to assess their sensitivity to a food-grade preparation of the lantibiotic, lacticin 3147, produced by Lactococcus lactis DPC3147. METHODS AND RESULTS: Saliva samples collected from children with varying oral health status were screened on Mitis Salivarius agar for the presence of pathogenic streptococci. Following selective plating, 16S rDNA sequencing and Pulsed Field Gel Electrophoresis (PFGE), 15 distinct strains of Strep. mutans were identified. These were grouped according to their relative sensitivity to lacticin 3147 which ranged from 0.78 to 6.25%; relative to a sensitive indicator strain, Lactococcus lactis ssp. lactis HP. Inhibition of indicator Strep. mutans strains from sensitive, intermediate and tolerant groupings were assessed in microtitre plate assays with increasing concentrations of lacticin 3147. The concentration of lacticin 3147 required to give 50% growth inhibition correlated with their relative sensitivities (as assayed by well diffusion methodology) and ranged from 1280 to 5120 AU ml(-1). Concentrated preparations of lacticin 3147 caused a rapid killing of Strep. mutans strains in broth. Moreover, in human saliva deliberately spiked with Strep. mutans, the pathogen was eliminated (initial inoculum of 10(5)) in the presence of 40,000 AU ml(-1) of lacticin 3147. Furthermore, a food-grade lacticin 3147 spray dried powder ingredient was assessed for the inhibition of Strep. mutans in human saliva, spiked with a strain of intermediate sensitivity, resulting in up to a 4-log reduction in counts after 20 min. CONCLUSION: A food grade preparation of lacticin 3147 was effective in the inhibition of oral Strep. mutans. SIGNIFICANCE AND IMPACT OF THE STUDY: The inhibition of oral streptococci by food grade preparations of lacticin 3147 may offer novel opportunities for the development of lacticin 3147 as an anti-cariogenic agent particularly in the area of functional foods for the improvement of oral health.

Bacterial Proteins↗

PubMed2004

rpoB gene sequence-based identification of aerobic Gram-positive cocci of the genera Streptococcus, Enterococcus, Gemella, Abiotrophia, and Granulicatella.

We developed a new molecular tool based on rpoB gene (encoding the beta subunit of RNA polymerase) sequencing to identify streptococci. We first sequenced the complete rpoB gene for Streptococcus anginosus, S. equinus, and Abiotrophia defectiva. Sequences were aligned with these of S. pyogenes, S. agalactiae, and S. pneumoniae available in GenBank. Using an in-house analysis program (SVARAP), we identified a 740-bp variable region surrounded by conserved, 20-bp zones and, by using these conserved zones as PCR primer targets, we amplified and sequenced this variable region in an additional 30 Streptococcus, Enterococcus, Gemella, Granulicatella, and Abiotrophia species. This region exhibited 71.2 to 99.3% interspecies homology. We therefore applied our identification system by PCR amplification and sequencing to a collection of 102 streptococci and 60 bacterial isolates belonging to other genera. Amplicons were obtained in streptococci and Bacillus cereus, and sequencing allowed us to make a correct identification of streptococci. Molecular signatures were determined for the discrimination of closely related species within the S. pneumoniae-S. oralis-S. mitis group and the S. agalactiae-S. difficile group. These signatures allowed us to design a S. pneumoniae-specific PCR and sequencing primer pair.

Base Sequence↗

PubMed1981

Studies on streptococci. I. Distribution of fecal streptococci in man.

To understand the significance to the host of streptococci as part of the intestinal microflora, we first tried to investigate the distribution of human fecal streptococci on the species level. Of the selective media compared, KMN agar was more effective than the other media for the isolation of streptococci from human feces. We made an effort to improve streptococcal classification. Especially we used utilization of 1% pyruvate, 1% arginine, and 1% citrate for differentiation between Streptococcus faecalis and S. faecium. In a tellurite tolerance test, S. faecalis was distinguished more clearly from S. faecium in the medium containing 0.16 or 0.32% tellurite. We devised methods of presumptive identification of fecal streptococci from the results of the characteristics of 1,442 isolates. These methods enabled us to identify many strains rapidly. Different results in the distribution of species of streptococci between children and adults were observed. S. faecalis and S. faecium were isolated constantly from both groups. S. bovis and S. avium were isolated frequently from the feces of children. On the other hand, "viridans" streptococci, e.g. S. salivarius, S. mitis and S. MG-intermedius were present at a high frequency in, and no S. avium could be isolated from, the feces of adults.

Adult↗

PubMed2002

Vaccination with FimA from Streptococcus parasanguis protects rats from endocarditis caused by other viridans streptococci.

The FimA protein of Streptococcus parasanguis is a virulence factor in the rat model of endocarditis, and immunization with FimA protects rats against homologous bacterial challenge. Because FimA-like proteins are widespread among the oral streptococci, the leading cause of native valve endocarditis, we evaluated the ability of this vaccinogen to protect rats when challenged by other streptococcal species. Here we report that FimA vaccination produced antibodies that cross-reacted with and protected against challenge by the oral streptococci S. mitis, S. mutans, and S. salivarius. FimA thus has promise as a vaccinogen to control infective endocarditis caused by oral streptococci.

Animals↗

PubMed1998

Effect of ultrasonic cleaning on microorganisms.

PURPOSE: To establish a method to measure microbial kill caused by ultrasonic cleaning. Secondarily, to estimate the escape of bacteria from the ultrasonic cleaning solutions during operation of the unit. MATERIALS AND METHODS: Three commercial enzymatic detergents and saline were used as cleaners. Depending on detergent, initial operational temperature was 21 degrees C, 37 degrees C or 60 degrees C. Streptococcus mutans ATCC 25175 (S. mutans suspensions) was adjusted to a final concentration of 1.0 x 10(3) cells/mL in saline. Suspensions (2000 mL) at the desired temperatures were added to the cleaner. Aliquots were removed, serially diluted in letheen broth and spread plated over mitis salivarius agar. Appropriate amounts of detergent solutions were added to S. mutans suspensions and the cleaner operated for 20 minutes. Aliquots were then removed and plated. The process was repeated twice. Plates were aerobically incubated at 37 degrees C for 7 days and the colonies counted. The procedure was repeated using three temperatures of S. mutans suspensions (21 degrees C, 37 degrees C or 60 degrees C), but without detergent or ultrasound. Also, detergents were added to 21 degrees C S. mutans suspensions and allowed to sit for 20 minutes without ultrasonic cleaning. Microbial sampling was done as previously described. RESULTS: Results when ultrasound was used indicated that little kill (5-15%) occurred in 21 degrees C or 37 degrees C detergent solutions. Greater kill (25-35%) was noted with 21 degrees C and 37 degrees C saline. Complete kill was accomplished with 60 degrees C saline or the 60 degrees C detergent solution. When ultrasound and detergent were not used, there was no kill in 21 degrees C and 37 degrees C saline, but complete kill in 60 degrees C saline. In the absence of ultrasound no kill was noted in 21 degrees C S. mutans suspensions to which detergent had been added. Total kill of S. mutans was observed in 60 degrees C saline or 60 degrees C detergent with ultrasound or after a 20-minute exposure in 60 degrees C saline without ultrasonic cleaning. Very few bacteria escaped from the ultrasonic cleaning solutions into the air during the cleaning process. Placement of the unit lid effectively reduced emissions to zero.

Coenzymes↗

PubMed1983

Fluorogenic selective and differential medium for isolation of fecal streptococci.

Of 44 fluorogenic substrates tested for their ability to differentiate species of fecal streptococci, four yielded species-differentiating reactions. The remaining substrates either yielded uniformly positive, negative, or variable strain-dependent reactions. One substrate, 4-methylumbelliferone-alpha-D-galactoside, was hydrolyzed by Streptococcus bovis and S. faecium and its biotypes. 4-Methylumbelliferone-alpha-D-galactoside and a colorimetric starch substrate were incorporated into the fecal streptococcal selective medium of Donnelly and Hartman (Appl. Environ. Microbiol. 35:576-581, 1978). Three phenotypic groups were identifiable on the new fluorescent gentamicin-thallous-carbonate agar: (i) starch hydrolysis and fluorescence (S. bovis), (ii) no starch hydrolysis but fluorescence (S. faecium and its biotypes), and (iii) no starch hydrolysis or fluorescence (S. faecalis, S. avium, S. equinus, S. mitis, and S. salivarius). Of the presumptive identifications from sewage, swine, and bovine samples, 86% were confirmed as being correct. The new medium has potential application in water, food, environmental, and possibly clinical microbiology.

Animals↗

PubMed1987

Analysis of heart-reactive antibodies induced in rabbits by immunization with Streptococcus mutans.

The induction of antibodies that react with human heart muscle in rabbits immunized with Streptococcus mutans and related organisms has been investigated in order to re-examine the reported antigenic cross-reactivity between the major cell wall protein antigen I/II of S. mutans and heart tissue. Serum from 2 of 8 rabbits hyperimmunized with whole cells of S. mutans, S. sobrinus, S. rattus, or S. mitis, assayed by immunofluorescence and radioimmunoassay, revealed antibodies reactive with sarcolemma that could be attributed to immunization. Antisera raised against several crude and purified antigens of S. mutans did not reveal heart-reactive antibodies, that could be attributed to antigenic similarity between heart and these antigens. An assay designed to detect antibodies that could simultaneously bind to both heart and antigen I/II of S. mutans failed to reveal cross-reactivity due to this antigen, although antibodies separately expressing these binding activities were demonstrable. IgM rheumatoid factor was elevated in several antisera to S. mutans, and could have contributed to some previous observations ascribed to antigenic cross-reactivity between S. mutans and human heart muscle.

Animals↗

PubMed1989

Diphtheria among alcoholic urban adults. A decade of experience in Seattle.

Three outbreaks of Corynebacterium diphtheriae infection occurred in Seattle's Skid Road from 1972 through 1982. The first involved a single toxigenic, intermedius biotype clone, whereas the second and third outbreaks involved nontoxigenic mitis and gravis strains. Of 1100 total infections, 947 (86%) were cutaneous. The incidence was highest in winter and spring. In Skid Road, the estimated attack rate during 17 months in 1974 to 1975 was 5% for whites and 27% for native Americans. Streptococcus pyogenes was isolated from 73% of diphtheritic and 41% of nondiphtheritic skin lesions (P less than 0.001). Skin infection and environmental contamination by C. diphtheriae were correlated. Complications occurred in 21% of symptomatic nasopharyngeal and 3% of cutaneous toxigenic intermedius infections (P less than 0.001), and were significantly correlated with ages 60 years or more. Preferential use of erythromycin for diphtheria and pyodermas preceded plasmid-mediated resistance to erythromycin in C. diphtheriae. Diphtheria outbreaks in urban alcoholic persons are associated with poor hygiene, crowding, season, contaminated fomites, underlying skin disease, hyperendemic streptococcal pyoderma, and introduction of new strains from exogenous reservoirs.

Adult↗

PubMed1992

Restricted distribution of Streptococcus milleri carbohydrate type antigens amongst other viridans streptococci.

The distribution of oral Streptococcus milleri carbohydrate type antigens in other viridans streptococcus species was examined. Rantz-Randall extracts of cells of the test strains grown in broth containing glucose were allowed to react with typing or grouping antisera for S. milleri serotypes a-k, or Lancefield groups A-G and K. Of 93 strains comprising more than 12 streptococcal species that included S. mutans and S. sanguis complexes, only 15 S. salivarius strains and one S. mitis strain were immunologically related to S. milleri serotype f. Unlike S. milleri strains, S. salivarius type f strains belonged to Lancefield group K, whereas the S. mitis strain was closely related to S. milleri serotype f but did not react with any of the Lancefield grouping antisera tested. Results suggest that oral S. milleri strains can be distinguished serologically from other oral viridans streptococci and that the typing antisera used in our researches might differentiate S. milleri isolates from the mouth from those associated with systemic purulent infections.

Antigens, Bacterial↗

PubMed1984

Disseminated tetracycline resistance in oral streptococci: implication of a conjugative transposon.

A DNA sequence specifying tetracycline resistance (Tcr) has been previously cloned from a clinical isolate of Streptococcus mutans designated U202 (J. A. Tobian and F. L. Macrina, J. Bacteriol. 152:215-222, 1982). We used this sequence as a molecular probe in studying the dissemination of Tcr among oral streptococcal species isolated from patients treated with tetracycline. Eleven strains (including S. sanguis I, S. sanguis II, S. mitis, and S. salivarius) from seven patients were examined by Southern blot analysis. Seven strains showed strong hybridization to the Tcr probe, two showed weak hybridization, and two did not display detectable hybridization. Based on previous characterization of the cloned sequence, our data suggest the dissemination of the tetM class of resistance determinants among these oral streptococci. One of the clinical S. sanguis I isolates studied was able to transfer its Tcr phenotype to other oral streptococci and to enteric streptococci in the absence of plasmid DNA. This transfer appeared to be conjugation-like on the basis of its insensitivity to DNase and its dependence on intimate cell-to-cell contact. Using the cloned Tcr sequence, we were able to study the progeny of the matings. Our data suggest that this resistance transfer element occupies a chromosomal location in streptococcal cells and that it strongly resembles the conjugative transposon Tn916 in its behavior.

Cloning, Molecular↗

PubMed1990

Utilization of mucin by oral Streptococcus species.

The ability of oral Streptococcus strains to utilize oligosaccharide chains in mucin as a source of carbohydrate was studied in batch cultures. Pig gastric mucin, as a substitute of human salivary mucin, was added to chemically defined medium containing no other carbohydrates. Strains of S. mitior attained the highest cell density, while mutans streptococci: S. mutans, S. sobrinus, S. rattus, grew very little in the medium with mucin. S. mitis, S. sanguis, and S. milleri in decreasing order, showed intermediate growth. Mucin breakdown as measured by sugar analyses indicated that oligosaccharide chains were only partially degraded. Every strain produced one or more exoglycosidases potentially involved in hydrolysis of oligosaccharide. The enzyme activities occurred mainly associated with the cells, and very little activity was found in the culture fluids. The relationships between glycosidase activities and growth, or mucin degradation were not always clear.

Animals↗

PubMed1975

Immunoelectron microscopic identification and localization of Streptococcus sanguis with peroxidase-labeled antibody: localization of surface antigens in pure cultures.

An indirect method of localizing antigens with horseradish peroxidase-labeled antibody was used to identify and localize surface antigens of Streptococcus sanguis at the ultrastructural level. An electron dense layer surrounding the cell wall could be distinguished without any additional electron microscope staining. This labeled layer represents an immune complex consisting of bacterial surface antigens, specific rabbit antisera, and peroxidase-labeled goat anti-rabbit globulins. Although with undiluted antisera slight cross-reactions occurred with S. salivarius and S. miteor (mitis), these could be readily distinguished from the more intense homologous reaction by their patchiness and the difference in distribution of the label. These cross-reactions were eliminated by appropriate dilutions of the antiserum. No cross-reactions occurred with S. mutans, S. faecalis, Actinomyces species, or Bacterionema, microorganisms wents indicated that horseradish peroxidase can become non-specifically adsorbed to the membrane of certain bacterial cells. Appropriate controls must, therefore, be included for localization of membrane associated antigens with horseradish peroxidase.

Actinomyces↗

PubMedDate not supplied

Susceptibility of Streptococcus mutans and Streptococcus sobrinus to cell wall inhibitors and development of a novel selective medium for S. sobrinus.

Representative strains of Streptococcus mutans and Streptococcus sobrinus showed differences in susceptibility to members of the monobactam group of beta-lactam antibiotics: S. sobrinus was less sensitive than S. mutans. The minimum inhibitory concentrations of aztreonam (AZT) and carumonam, both of which belong to this group, were 2,000 microg/ml for S. sobrinus and 125 microg/ml for S. mutans. Further addition of fosfomycin, bacitracin and sodium chloride to Mitis Salivarius agar (MS) supplemented with AZT resulted in growth inhibition of S. mutans and oral streptococci other than S. sobrinus, and was therefore used as a selective medium for S. sobrinus (MS-SOB medium). The average growth recovery of laboratory and clinically isolated strains of S. sobrinus on MS-SOB medium was 74.1% compared to that on MS medium. Seventy-eight percent of clinical samples in which S. sobrinus was detected yielded pure growth of S. sobrinus on MS-SOB medium.

Anti-Bacterial Agents↗