PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Streptococcus sanguis”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources
PubMed1979

Sanguicin, a bacteriocin of oral Streptococcus sanguis.

Streptococcus sanguis strain N-2 was found to produce a bacteriocin (sanguicin) which accumulates intracellularly. It was purified by sequential procedures about 98-fold with a recovery of 37% and appeared to be homogeneous on gel electrophoresis. Sanguicin was heat labile and was destroyed by digestion with pronase. The growth of several species of oral indigenous microorganisms was inhibited by sanguicin, of which Bacteriodes melaninogenicus was most susceptible. Sanguicin acted on susceptible cells as a bacteriostatic agent.

Amino Acids↗
PubMed1978

Plaque formation in vitro by Actinomyces viscosus in the presence of Streptococcus sanguis or Streptococcus mutans.

Actinomyces viscosus, growing on a tooth in the presence of sucrose, slowly produced a loosely-attached plaque, the pH being 6.1 after 120 h. When the tooth was inoculated simultaneously with A. viscosus and either Streptococcus sanguis or Streptococcus mutans, firmly-adherent plaque was quickly formed and the pH fell below 5 after 33 h with the former Streptococcus and 24 h with the latter. A. viscosus disappeared from each mixed plaque by 120 h.

Actinomyces↗
PubMed1978

Compounds which affect the adherence of Streptococcus sanguis and Streptococcus mutans to hydroxyapatite.

Several compounds were evaluated in an in vitro assay system for their ability to block the adherence of Streptococcus sanguis to saliva-coated hydroxyapatite and Streptococcus mutans to dextran-coated hydroxyapatitite. Fatty acids, ranging from C-12 to C-20, the enzyme amylase, chlorhexidine, human sera, and several serum proteins blocked S sanguis adherence to saliva-coated hydroxyapatite. Chlorhexidine blocked S mutans adherence to dextran-coated hydroxyapatite, but human sera and serum proteins did not. The effects of these compounds on the adherence of these organisms to hydroxyapatite may help in the development of specific plaque control methods for use in human populations.

Adhesiveness↗
PubMed1978

Specificity of salivary-bacterial interactions: role of terminal sialic acid residues in the interaction of salivary glycoproteins with Streptococcus sanguis and Streptococcus mutans.

Four highly purified salivary glycoproteins were used to study salivary-bacterial interactions. One pair of glycoproteins was mucin-like in composition, whereas the second pair was not. By an agglutination assay, it was found that only the mucin-glycoproteins agglutinated Streptococcus sanguis and S. mutans. Removal of sialic acid from these molecules resulted in a loss of agglutination of S. sanguis but not of S. mutans. The agglutination phenomenon was shown to require a salivary macromolecule of at least 150,000 daltons.

Agglutination↗
PubMed1976

Effect of pH on competence development and deoxyribonucleic acid uptake in Streptococcus sanguis (Wicky).

Streptococcus sanguis (Wicky) cells, strain WE4, developed little or no competence and failed to autolyze in permissive conditions when treated with competence factor (CF) below PH 7.0. This lack of activity was directly correlated with the inability of the cells to bind or take up CF at pH values of 5.5, 6.0, and 6.5. On the other hand, competent cells bound deoxyribonucleic acid molecules maximally below pH 7.0 and transformed maximally at pH 6.5. Deoxyribonucleic acid was optimally bound to cells in a deoxyribonuclease-resistant form at pH values between 7.0 and 8.5. Concomitant with this binding, undefined acid-soluble DNA fragments appeared in the culture menstrua. CF binding and uptake by cells was not only influenced by low pH but also by low temperature. At 0 C, WE4 cells bound only 4% of the input CF and took up less than 1% into a trypsin-insensitive state compared to cells treated at 37 C. Cells treated with CF at 0 C did not autolyze when transferred to permissive conditions. The results presented in this report extend earlier findings that showed that competence development and autolysis are related to the uptake of CF.

Bacterial Proteins↗
PubMed1976

Purification and some properties of free and cell-associated dextransucrase from Streptococcus sanguis.

Dextransucrase of Streptococcus sanguis occurred in cell-free and cell-associated forms. Cell-free dextransucrase was purified by four successive chromatographies on Bio-Gel P 60, DEAE-cellulose, and Bio-Gel P 200 from the culture supernatant. The purification of cell-associated dextransucrase was made from the pellet of Streptococcus sanguis culture. Bacterial pellet was extracted with 1 M phosphate buffer (pH 6.0) and chromatographied by using an immunosorbent column. The two enzymes gave single bands in polyacrylamide gel electrophoresis. The molecular weight determined by sodium dodecyl sulfate polyacrylamide gel was about 100 000 daltons for the two forms of dextransucrases. The optimum pH of the cell-free and cell-associated enzymes was around 6 and the temperature optimum was broad for the two enzymes. The KM values for sucrose were respectively 2 mM and 3 mM for cell-free and cell-associated enzymes. When primer dextran was added, the reaction velocity increased but the KM for sucrose remained the same, and the KA for dextran was 200 muM for the two dextransucrases. Trehalose and maltose acted also as glucosyl residue acceptors. Purified enzymes had dextran synthesising activity and invertase-like activity. The same properties of the two forms of enzymes and the positive cross reaction against anti free and anti cell-associated globulins stongly suggest the identity of the two enzymes.

Chromatography, Gel↗
PubMed1977

Glucosyltransferase production by Streptococcus sanguis 804 (NCTC 10904).

Streptococcus sanguis 804 (NCTC 10904) was grown ih batch culture at constant pH. and the glucosyltransferase activity of the supernatant was assayed over a 40-h growth period. The optimum pH for enzyme production was 7.0 to 7.2. During growth of the culture, three reproducible phases of enzyme activity were observed. The polysaccharides synthesized during each of these phases were characterized as dextran-like glucans by analysis of acid hydrolysates, gas-liquid chromatography, and a specific aggregation technique. The glucans were studied further by infrared spectroscopy, enzymic degradation, and periodate oxidation. Differences in the proportions of alpha-(1 leads to 3)- and alpha-(1 leads to 6)-linkages were observed. The results suggest that glucan synthesis by S. sanguis involves a multienzyme system.

Agglutination↗
PubMed1976

Transformation of Streptococcus sanguis Challis by plasmid deoxyribonucleic acid from Streptococcus faecalis.

Plasmid deoxyribonucleic acid (DNA) from Streptococcus faecalis, strain DS5, was transferred to the Challis strain of Streptococcus sanguis by transformation. Two antibiotic resistance markers carried by the beta plasmid from strain DS5, erythromycin and lincomycin, were transferred to S. sanguis at a maximum frequency of 1.8 x 10-5/colony-forming unit. Approximately 70% of the covalently closed circular DNA isolated from transformant cultures by dye buoyant density gradients was shown to be hybridizable to beta plasmid DNA. Two major differences were observed between the beta plasmid from S. faecalis and the plasmid isolated from transformed S. sanguis: (i) the beta plasmid from strain DS5 sedimented in velocity gradients at 43S, whereas the covalently closed circular DNA from transformed Challis sedimented at 41S, suggesting a 1.5-Mdal deletion from the beta plasmid occurred; (ii) although the 43S beta plasmid remained in the supercoiled configuration for several weeks after isolation, the 41S plasmid was rapidly converted to a linear double-stranded molecule. Attempts to transform S. sanguis with the alpha plasmid from S. faecalis, strain DS5, were unsuccessful.

DNA, Bacterial↗
PubMed1977

Transfection of Streptococcus sanguis by phage deoxyribonucleic acid isolated from Streptococcus mutans.

Streptococcus sanguis ATCC 10556 cells were infected with free phage DNA of S, mutans strain PK 1. Two transformants were isolated which made colonies with large mucoid forms on mitis-salivarius agar. Both transformants had an increased ability to synthesize insoluble glucan and showed an adhesive nature on glass surfaces. These characteristics of the transformants bear a resemblance to S. mutans. These transformants had many physiological characteristics by which they could be recognized as S. sanguis. However, they resembled S. salivarius in forming a large amount of soluble fructan. Furthermore, the transformant cells did not produce ammonia from arginine, whereas their parent cells did.

Bacteriolysis↗
PubMed1979

Enhanced transformability with heterospecific deoxyribonucleic acid upon removal of nascent ribonucleic acid from the Streptococcus sanguis genome.

Treatment of Streptococcus sanguis recipient cells with rifampin (RIF) at the time of deoxyribonucleic acid (DNA) addition was an effective means of reducing discrimination, that is, of causing an increase in the number of transformants induced by irreversibly bound heterospecific DNA without significantly changing the number induced by bound homospecific DNA. RIF was unable to reduce discrimination when the recipient cells were RIF resistant due to an altered ribonucleic acid (RNA) polymerase. When recipient cells were treated at the time of DNA addition with concentrations of streptolydigin (STG) as inhibitory of RNA synthesis as RIF, discrimination was not reduced. The kinetics of RNA synthesis inhibition with these inhibitors indicated that, as reported for other bacterial species, RIF inhibited the initiation of transcription by RNA polymerase, whereas STG inhibited the progression of RNA polymerase at any point. Pulse-labeling of RNA immediately before STG addition showed that, if cells were incubated under STG inhibition for 10 to 15 min, their nascent RNA was degraded. Genome-bound RNA polymerase was not released under these conditions. When recipient cells were incubated with STG until nascent RNA was degraded and then exposed to transforming DNA, STG was as effective as RIF in reducing discrimination. The presence of nascent RNA was thereby implicated in the transforming inefficiency of incompletely homologous DNA.

Aminoglycosides↗
PubMed1975

Characterization of an antibody directed against a surface component of normal and pleomorphic cells of Streptococcus sanguis.

Whole cells of Streptococcus sanguis were utilized as an immunoadsorbent to purify large quantities of an antibody (S1) directed against a cell surface component. The S-1 antibody was isolated from antisera to normal (N) and pleomorphic (O) cells by a similar adsorption-elution procedure. The S-1 antibody isolated from antisera to N cells reacted in gel diffusion in identify with the S-1 antibody to O cells, indicating that the antigen which binds S-1 antibody (Ag-1) may not be radically altered when cells become pleomorphic. The S-1 antibodies directed against both N and O cells had restricted heterogeneity, indicating that for both types of cell Ag-1 may have a simple repeating structure. However, N cells were agglutinated to a greater extent by S-1 antibody than O cells. In addition the distribution of the bound S-1 antibody became altered as the cells became pleomorphic. Utilizing the technique of indirect immunofluorescence we observed that the S-1 antibody was distributed evenly on the surface of N cells. As the cells became pleomorphic, the antibody appeared to bind preferentially at the cell poles (capping). Later, as the cells became more grossly deformed, additional bands of immunofluorescence appeared to bisect the cells. Electron microscopic analysis indicated that the bound antibody was not associated with septal notches. The results suggest that the arrangement rather than the immunological properties of Ag-1 became altered as cells became pleomorphic.

Agglutination↗
PubMed1978

Mechanism of coaggregation between Actinomyces viscosus T14V and Streptococcus sanguis 34.

Actinomyces viscosus T14V and Streptococcus sanguis 34 coaggregate by a mechanism which is not inhibited by 1 M NaCl, is dextran independent, requires calcium, is pH dependent with an optimum at pH 8.0 to 8.5, and appears to require the interaction of a protein or glycoprotein on A. viscosus with a carbohydrate on S. sanguis. The coaggregation is inhibited more than 80% by 0.01 M lactose, 0.02 M beta-methyl-D-galactoside, or 0.05 M D-galactose; inhibition of coaggregation was less than 10% in 0.1 M alpha-methyl-D-galactoside, melibiose, maltose, cellobiose, sucrose, and a number of monosaccharides. At very high concentrations of enzyme, protease from S. griseus destroyed the reactive site on A. viscosus but not on S. sanguis. Both were totally resistant to dextranase. Periodate (0.01 M; pH 4) inactivated both bacteria. The ability of S. sanguis to coaggregate with A. viscosus was not destroyed by phenol-water extraction at 65 degrees C for 15 min. When the bacteria were cultured under specified conditions, the coaggregation was highly reproducible. Under the same conditions, T14AV, the avirulent mutant of A. viscosus T14V, did not coaggregate with S. sanguis 34. Electron microscopic studies of coaggregates, labeled immunochemically with antibody to A. viscosus, indicated that fibrils on A. viscosus may be involved in the coaggregation.

Actinomyces↗
PubMed1979

Superhelical DNA in Streptococcus sanguis: role in recombination in vivo.

Competent Streptococcus sanguis treated with non-lethal doses of coumermycin A1 immediately before or after uptake of radioactive transforming DNA were reduced in their capacity to yield transformants. This treatment did not alter bacterial ability to bind DNA in DNase I-resistant form, nor did it prevent the single-stranded donor DNA-recipient protein complexes formed upon uptake at the surface of the bacteria from translocating to chromosomal sites. Inhibition of transformation by heterospecific DNA was greater than that by homospecific DNA. The reduction in transformant yield was not accompanied by any loss of donor counts incorporated into the recipient chromosome, but rather by a loss of genetic activity of incorporated donor material indicating a failure of genetic integration and degradation of donor DNA as a consequence of coumermycin treatment. The inhibitory effect of coumermycin on transformation was associated with in vivo loss of chromosomal DNA superhelicity, The chromosomal DNA remained intact, however, indicative of inhibition of a gyrase-like enzyme responsible for the maintenance of negative supercoiling of the S. sanguis chromosome. Upon treatment with the drug, a coumermycin-resistant mutant strain showed neither loss of chromosomal superhelicity nor any inhibitory effect on genetic integration of donor DNA. The evidence supports the idea that chromosomal superhelicity promotes genetic recombination in vivo.

Aminocoumarins↗
PubMed1978

Fate of homospecific transforming DNA bound to Streptococcus sanguis.

The fate of [3H]DNA from Streptococcus sanguis str-r43 fus-s donors in [14C]S. sanguis str-s fus-r1 recipients was studied by examining the lysates prepared from such recipients at various times after 1 min of exposure to DNA. The lysates were analyzed in CsCl and 10 to 30% sucrose gradients; fractions from the gradients were tested for biological activity and sensitivity to nucleases, subjected to various treatments and retested for nuclease sensitivity, and run on 5 to 20% neutral and alkaline sucrose gradients. The results demonstrate that donor DNA bound to S. sanguis cells in a form resistant to exogenous deoxyribonuclease is initially single stranded and complexed to recipient material. Donor DNA can be removed from the complex upon treatment of the complex with Pronase, phenol, or isoamyl alcohol-chloroform. Within the complex, donor DNA is relatively insensitive to S1 endonuclease but can regain its sensitivity by treatment with phenol. With time the complex moves as a whole to associate physically with the recipient chromosome. After a noncovalent stage of synapsis, donor material is covalently bonded to and acquires the nuclease sensitivity of recipient DNA, while donor markers regain transforming activity and become linked to resident markers.

Bacterial Proteins↗