| the effect of inoculating strains of streptococcus mutans and streptococcus sanguis upon caries incidence and bacterial content of plaque in rats. | | 1973 | 4518742 |
| morphological changes in streptococcus sanguis associated with growth in the presence of oxygen. | | 1973 | 4518763 |
| a charged component in purified polysaccharide preparations from streptococcus mutans and streptococcus sanguis. | | 1974 | 4528382 |
| cell-bound glucosyltransferase activity of streptococcus sanguis strain 804. | | 1974 | 4531859 |
| the incidence and significance of streptococcus sanguis, streptococcus mutans and streptococcus salivarlius in root canal cultures from human teeth. | | 1974 | 4532212 |
| induction of unbalanced growth and death of streptococcus sanguis by oxygen. | streptococcus sanguis has normal streptococcal morphology when grown in a nitrogen atmosphere but undergoes gross morphological alterations when grown in the presence of oxygen (o cells). studies were made of the relationship between the development of pleomorphism and the loss of viability which accompanied it in o cultures of s. sanguis. the development of pleomorphism appears to involve two events. the first step, or triggering event, occurs in log-phase cultures in the presence of oxygen. th ... | 1973 | 4583207 |
| efficiency of various growth media in recovering oral bacterial flora from human dental plaque. | mm10 sucrose blood agar (mm10 sb agar), n(2)c agar, schaedler agar (sh agar), and mitis salivarius agar (ms agar) were tested for their ability to recover human dental plaque flora by a continuous anaerobic procedure and by a conventional anaerobic method. mm10 sb agar yielded higher recovery of bacteria from plaque samples as determined by the enumeration of colony-forming units (cfu). the cfu on n(2)c agar, sh agar, and ms agar were lower than mm10 sb agar when the continuous anaerobic procedu ... | 1973 | 4584588 |
| identification of streptococcus sanguis by defined immunofluorescence. | | 1974 | 4601008 |
| saliva-induced aggregation of oral streptococci. | cells of several species of oral microorganisms have been shown, in earlier studies, to be aggregated by saliva. in the present study some of the basic properties of the aggregation system are examined. the observation is made that the saliva-induced aggregates of streptococcus sanguis and s. mitis can be dissociated to stable particles which consist of about 100 cells and have a median diameter of about 4.5 mum. it is proposed that these are subunits, or core aggregates, of the large primary ag ... | 1972 | 4629653 |
| antigens of streptococcus sanguis. | an antigenic analysis of the alpha-hemolytic streptococci isolated from dental plaque was performed by use of antisera against a strain of streptococcus sanguis (m-5) which was isolated from dental plaque. immunoelectrophoretic and ouchterlony tests of rantz and randall extracts of 45 strains gave positive reactions with the m-5 antisera. these strains represented 60% of the strains tested. the number of antigens which could be identified in these extracts varied from one to five and were design ... | 1973 | 4633291 |
| ecology of human oral lactobacilli. | lactobacilli were found in saliva, on teeth, and on the dorsum of the tongue, the vestibular mucosa, and the hard palate in humans. their proportions in saliva, expressed as percentage of the anaerobically cultivable flora, were 10- to 100-fold higher than those on the tooth surface, but were comparable to those on the epithelial surfaces. the adherence of lactobacillus casei and l. fermenti to oral surfaces was compared with that of streptomycin-labeled streptococcus sanguis and s. salivarius b ... | 1972 | 4637297 |
| properties of a streptococcus sanguis (group h) bacteriocin and its separation from the competence factor of transformation. | sth(1), a streptocin elaborated by group h streptococcus strain challis, is lethal for group h streptococcus strain wicky and is produced maximally during the exponential growth phase of liquid medium cultures. crude streptocin preparations are resistant to oxidation and display a biphasic ph stability (stability being maximal at ph 5.0 and 10.0). survivor studies indicate that streptocin-mediated killing is a "one-hit" phenomenon and proceeds rapidly. the streptocin has been purified 50-fold wi ... | 1973 | 4725617 |
| carbon dioxide control of lag period and growth of streptococcus sanguis. | a carbon dioxide requirement for growth of streptococcus sanguis was readily demonstrated in a fermentor where the gas atmosphere could be controlled. growth at a maximum rate occurred immediately in response to the appropriate co(2) concentration; growth stopped when co(2) was deleted. washed inocula consisting of exponentially growing cells required a minimum of 2.4% co(2), postexponential phase cells needed 1.2 to 1.8% co(2) immediately and 2.4% co(2) shortly thereafter, whereas stationary ph ... | 1974 | 4811542 |
| neuraminidase activity in streptococcus sanguis and in the viridans group, and occurrence of acylneuraminate lyase in viridans organisms isolated from patients with septicemia. | the enzyme neuraminidase (ec 3.2.1.18) was found to be strongly active in different types of streptococcus sanguis and s. viridans, and, in addition, the occurrence of the enzyme acylneuraminate pyruvate lyase (ec 4.1.3.3) was described in s. viridans. the enzyme-active bacteria strains were isolated from blood cultures of patients with septicemia. whereas s. sanguis lost its strong neuraminidase activity after some weeks, s. viridans retained its enzyme activity for a long time in culture. immu ... | 1974 | 4816461 |
| alteration of macromolecular synthesis and membrane permeability by a streptococcus sanguis bacteriocin. | | 1974 | 4822122 |
| inhibition of the development of competence in streptococcus sanguis (wicky) by reagents that interact with sulfhydryl groups: discernment of the competence process. | reagents that interact with sulfhydryl groups are shown to inhibit competence factor (cf)-induced competence development in streptococcus sanguis (wicky) strain we4 (wicky 4 ery(r)). inhibition is correlated with specific inhibition of either the function or biosynthesis of three competent cell-related proteins and is reversed by either 2-mercaptoethanol or dithiothreitol. mercuric chloride (5 mum) or n-ethylmaleimide (nem; 50 mum) inhibited (i) the function but not the biosynthesis or activatio ... | 1974 | 4829923 |
| glycogen accumulation by pleomorphic cells of streptococcus sanguis. | | 1974 | 4830758 |
| isolation of an enzyme from streptococcus sanguis which specifically cleaves iga. | | 1974 | 4832315 |
| in vitro attachment of streptococci to the tooth surface. | the ability of streptococcus strains to adhere to the tooth surface in vitro was investigated. polished enamel slabs, with and without acquired pellicles, were incubated with buffer suspensions of oral streptococci, and attached bacteria were counted under a microscope using incident light. low numbers of bacteria adhered to uncoated enamel; the presence of an acquired pellicle significantly enhanced the attachment of all strains tested. the adherence of streptococcus sanguis was significantly g ... | 1974 | 4856824 |
| ability of veillonella and neisseria species to attach to oral surfaces and their proportions present indigenously. | the present study describes the distribution of veillonella and neisseria species in the human oral cavity and indicates that their ability to attach to oral surfaces correlates with their proportions found in various sites of the mouth. the mean percentages of veillonella and neisseria of the total flora cultivable on anaerobic blood-agar plates was found to be: plaque, 0.75 and <0.13, respectively; lip, 0.38 and <0.05; cheek, 0.66 and <0.14; tongue dorsum, 9.4 and <0.12; saliva, 5.0 and <0.9. ... | 1971 | 5154885 |
| proportions of streptococcus sanguis, an organism associated with subacute bacterial endocarditis, in human feces and dental plaque. | the relative absence of streptococcus sanguis in human feces, in contrast to its high concentration on teeth, supports the concept of the mouth as the likely bacterial source in cases of subacute bacterial endocarditis involving this organism. | 1971 | 5154899 |
| zooglea-forming streptococci, resembling streptococcus sanguis, isolated from dental plaque in man. | | 1965 | 5216256 |
| inhibition of streptococcal dextransucrase by sera of rabbits infected with streptococcus sanguis. | | 1968 | 5244310 |
| prevalence of streptococcus sanguis and streptococcus mutans in the mouth of persons wearing full-dentures. | | 1969 | 5255438 |
| reaction rate of dextransucrase from streptococcus sanguis in the presence of various compounds. | | 1969 | 5255458 |
| purification and properties of dextransucrase from streptococcus sanguis. | | 1969 | 5255459 |
| the effect of carbohydrate restriction on the presence of streptococcus mutans, streptococcus sanguis and iodophilic polysaccharide-producing bacteria in human dental plaque. | | 1970 | 5267941 |
| adherence as a determinant of the presence of streptococcus salivarius and streptococcus sanguis on the human tooth surface. | | 1970 | 5275860 |
| dextransucrase from streptococcus sanguis further characterization. | | 1971 | 5279546 |
| establishment of streptococcus sanguis in the mouths of infants. | | 1970 | 5280120 |
| growth of streptococcus mutans and streptococcus sanguis in mixed culture. | | 1971 | 5284308 |
| distribution and serological specificity of sialidase produced by various groups of streptococci. | the occurrence of a streptococcal sialidase (designated st-sialidase) in culture fluids of various streptococci was investigated. st-sialidase was found to occur in strains belonging to groups a, b, c, e, g, h, and l, and the unclassified strains, streptococcus sanguis and streptococcus uberis. st-sialidase of group a was confined predominantly to types 4 and 22. st-sialidases, extracted from the culture fluids of some selected strains, were antigenic, eliciting the formation of antibody which e ... | 1969 | 5344099 |
| predominant catalase-negative soil bacteria. i. streptococcal population indigenous to soil. | streptococci related to streptococcus sanguis were shown to represent a major segment of the bacterial flora of certain soils. upon initial isolation, these streptococci were quite pleomorphic and displayed morphological characteristics common to several other genera of bacteria, but after prolonged cultivation on laboratory media the isolates demonstrated a typical streptococcal morphology. it was proposed that a requirement for correction of the control mechanisms affecting growth rate and cel ... | 1969 | 5775904 |
| sialidase-like enzymes produced by group a, b, c, g, and l streptococci and by streptococcus sanguis. | a group of enzymes were prepared from the culture fluids of streptococci belonging to groups a, b, c, g, and l, and from a strain of streptococcus sanguis. these streptococcal enzymes (designated st-sialidases) released a substance shown to belong to the sialic acid group from the specific substrate bsm-st, a sialomucoid prepared from bovine submaxillary gland. they were inactive on n-acetylneuramin lactose prepared from bovine colustrum and on a sialomucoid prepared from bovine submaxillary muc ... | 1969 | 5776530 |
| plasmid transformation of streptococcus lactis protoplasts: optimization and use in molecular cloning. | the parameters affecting polyethylene glycol-induced plasmid transformation of streptococcus lactis lm0230 protoplasts were examined to increase the transformation frequency. in contrast to spreading protoplasts over the surface of an agar medium, their incorporation into soft agar overlays enhanced regeneration of protoplasts and eliminated variability in transformation frequencies. polyethylene glycol with a molecular weight of 3,350 at a final concentration of 22.5% yielded optimal transforma ... | 1984 | 6091544 |
| molecular cloning of the lactose-metabolizing genes from streptococcus lactis. | restriction endonucleases and agarose gel electrophoresis were used to analyze plasmid plm2001, which is required for lactose metabolism by streptococcus lactis lm0232. the enzymes xhoi, ssti, bamhi, and kpni each cleaved the plasmid into two fragments, whereas ecori and bglii cleaved the plasmid into seven and five fragments, respectively. sizing of fragments and multiple digestions allowed construction of a composite restriction map. the kpni fragments of plm2001 were cloned into the kpni clea ... | 1984 | 6091547 |
| immunogold electron microscopy of surface antigens of oral bacteria. | colloidal gold particles 3-6 nm in diameter were prepared and stabilized with the igg fraction of polyspecific rabbit antisera produced against four different oral bacteria. the immunogold markers were used in homologous reactions to label the bacteria in a preembedding procedure for electron microscopy. an indirect immunofluorescence procedure was concurrently used to optimize the labelling conditions before observation with the electron microscope. the immunogold markers labelled fibrillar str ... | 1984 | 6093974 |
| characterization and expression of a cloned tetracycline resistance determinant from the chromosome of streptococcus mutans. | a chromosomal tetracycline resistance (tcr) determinant previously cloned from streptococcus mutans into streptococcus sanguis (tobian and macrina, j. bacteriol. 152:215-222, 1982) was characterized by using restriction endonuclease mapping, deletion analysis, and southern blot hybridization. deletion analysis allowed localization of the tcr determinant to a 2.8-kilobase region of the originally cloned 10.4-kilobase sequence. this cloned determinant hybridized to a representative of the tetm cla ... | 1984 | 6094475 |
| return of streptococcus faecalis dna cloned in escherichia coli to its original host via transformation of streptococcus sanguis followed by conjugative mobilization. | cloning vectors were introduced into streptococcus faecalis by conjugation. a conjugative plasmid (pva797) and cloning vector pva838 recombined in streptococcus sanguis at homologous sequences, forming a cointegrate. the pva797::pva838 cointegrate transferred to s. faecalis by conjugation. recombination between homologous sequences resolved the cointegrate in the s. faecalis transconjugants, and pva797 and pva838 segregated because of incompatibility. s. faecalis strains that received pva838 by ... | 1984 | 6094500 |
| evidence that glucose and sucrose uptake in oral streptococcal bacteria involves independent phosphotransferase and proton-motive force-mediated mechanisms. | sugar transport and glycolysis in streptococcus sanguis nctc 7865, streptococcus mitis atcc 903, streptococcus salivarius nctc 8606 and several strains of streptococcus mutans were investigated by following the rate of acid production by washed bacteria at a constant ph of 7.0. the phosphoenolpyruvate-phosphotransferase system (pts) was inhibited by low concentrations of chlorhexidine. when this pts-inhibitory concentration of chlorhexidine was added to cells washed and re-suspended in kcl, gluc ... | 1984 | 6097204 |
| molecular characterization of unique deletion mutants of the streptococcal plasmid, pam beta 1. | | 1980 | 6100905 |
| the effect of intensive antibacterial therapy on the sulcular environment in monkeys. part i. changes in the bacteriology of the gingival sulcus. | the changes induced in the bacteriology of the gingival sulcus were evaluated as part of a study considering the keratinizing potential of the sulcular epithelium when bacterial plaque was essentially eliminated. two rhesus monkeys were scaled and placed on a daily therapeutic regimen which included a prophylaxis, systemic tetracycline, and topical chlorhexidine. over the 40 day experimental period and 74 days post-therapy, subgingival plaque samples were taken periodically. the plaque samples w ... | 1980 | 6102117 |
| lethal effect of a heterologous murein hydrolase on penicillin-treated streptococcus sanguis. | nine strains of streptococcus sanguis exhibited tolerance to benzylpenicillin: the growth of each strain was susceptible to penicillin with minimal inhibitory concentrations of 0.1 mug/ml or lower, but the bacteriolytic and bactericidal effects were limited in each case. the tolerance of these bacteria was also reflected in the large discrepancies between the minimal inhibitory and minimal bactericidal concentrations for benzylpenicillin. the hypothesis that a natural deficiency of endogenous mu ... | 1980 | 6104471 |
| the use of monoclonal antibodies in the study of lactose-sensitive adherence of actinomyces viscosus t14v. | | 1980 | 6108369 |
| bacterial invasion of pulpal dentin wall in vitro. | instrumented root canals of extracted human teeth were inoculated with known pulpal bacterial isolates. the inoculated teeth were immersed in the appropriate culture media and incubated at 37 degrees c for varying periods. streptococci multiplied in the root canals and invaded the radicular dentinal tubules. the extent of bacterial invasion was time-dependent. this experimental model of bacterial invasion was time-dependent. this experimental model may be useful in investigating the effect of in ... | 1982 | 6120188 |
| antibodies against the ag2 fimbriae of actinomyces viscosus t14v inhibit lactose-sensitive bacterial adherence. | monospecific antisera against the ag1 and ag2 fimbrial components of actinomyces viscosus t14v were produced by immunizing rabbits with immune precipitates of each antigen harvested from crossed-immunoelectrophoresis plates. the fab fragments prepared from these sera were used as specific reagents in immunoelectron microscopy to identify each fimbrial component on the bacterial surface and also were assayed for their abilities to prevent the coaggregation of a. viscosus t14v with streptococcus s ... | 1982 | 6124506 |
| whole-bacterial cell enzyme-linked immunosorbent assay for streptococcus sanguis fimbrial antigens. | a whole-bacterial cell enzyme-linked immunosorbent assay (bactelisa) was developed for detecting fimbrial antigens on streptococcus sanguis. in this assay, s. sanguis cells were directly adhered to polystyrene or polyvinyl via drying. use of the assay indicated that consistently high and uniform optical densities could be obtained from well to well. in addition, radioactive assaying indicated increased adsorption to the polystyrene wells over polyvinyl, suggesting that polystyrene may prove supe ... | 1982 | 6125528 |
| humoral immune response to oral microorganisms in periodontitis. | serum antibody titers from patients with periodontitis were compared with those from periodontally healthy subjects. with the micro-enzyme-linked immunosorbent assay, immunoglobulin g (igg), iga, and igm antibody titers to isolates of streptococcus sanguis, actinomyces viscosus, bacteroides gingivalis, bacteroides melaninogenicus subsp. intermedius, bacteroides gingivalis, bacteroides melaninogenicus subsp. intermedius, bacteroides ochraceus, and fusobacterium nucleation were determined. antibod ... | 1982 | 6126434 |
| [fibrinolytic system in human saliva activated by oral bacteria]. | | 1981 | 6129013 |
| corncob formation between fusobacterium nucleatum and streptococcus sanguis. | corncob formation in dental plaque was believed to be limited to strains of bacterionema matruchotii and streptococcus sanguis. we observed recently that strains of fusobacterium nucleatum also interacted with s. sanguis to form corncobs. since the fusobacteria are among the first anaerobic filaments to colonize subgingival plaque, these interactions could serve as a connecting link between the transformation of supra- to subgingival plaque. to further characterize these interactions, quantitati ... | 1983 | 6131871 |
| coaggregation of human oral cytophaga species and actinomyces israelii. | a total of 19 strains of oral cytophaga sp. obtained from subgingival plaque deposits were tested for their ability to coaggregate with strains of actinomyces israelii, a. viscosus, a. naeslundii, streptococcus sanguis, s. mutans, s. salivarius, and s. mitis. coaggregation was observed only with a. israelii. based on their coaggregation patterns with eight a. israelii strains, the cytophaga strains were distributed among three distinct groups: those that coaggregated with a. israelii pk16 but no ... | 1983 | 6133836 |
| association of fimbriae with the hydrophobicity of streptococcus sanguis fc-1 and adherence to salivary pellicles. | a nonhydrophobic mutant of streptococcus sanguis fc-1 was isolated which has a greatly diminished capacity for attaching to experimental salivary pellicles on hydroxyapatite surfaces and for aggregating with salivary components. the mutant appears to be defective in the synthesis of fimbriae, as judged by electron microscopic observations and by its inability to exhibit twitching motility. | 1983 | 6134679 |
| the function and distribution of different fimbriae on strains of actinomyces viscosus and actinomyces naeslundii. | actinomyces viscosus and actinomyces naeslundii differ in their abilities to colonize tooth and epithelial surfaces. these differences appear to be associated with the distribution of different fimbriae on the two species and with the distinct adherence-related functions of these structures. | 1984 | 6142065 |
| genetic transformation in streptococcus sanguis. simultaneous variation of surface-spreading, competence, hemagglutination and polar fimbriation in selected strains. | strains of streptococcus sanguis expressing spreading zones around the colonies and competence in genetic transformation, were subcultivated in the laboratory, and in three strains a variation to non-spreading colony morphology on human blood agar plates was observed. these variants were isolated and compared with the original strains by genetic transformation, hemagglutination and electron microscopy. in genetic transformation with streptomycin resistance as genetic marker, the non-spreading va ... | 1984 | 6152366 |
| electron microscopic visualization of extracellular polysaccharides on the cell wall of some streptococci. | the thickness of the acid polysaccharide capsule varied remarkably among the studied streptococci. in some strains, projections of the capsule and sloughing of the polysaccharide were observed in the medium. | 1980 | 6153663 |
| deoxyribonucleases of streptococcus sanguis. | three dnases, designated 1, 2 and 3 have been isolated from lysates of old (incompetent in genetic transformation) and logarithmic phase (competent) streptococcus sanguis strain challis cells. these dnases have different electrophoretic mobilities and immunological properties. influence of some activators and inhibitors on their activity was determined. molecular weights of 3 dnases are in the range of 52,000--57,000. all these enzymes are endonucleases which degrade native dna; thermally denatu ... | 1980 | 6155051 |
| adherence of oral streptococci to keratinized and nonkeratinized human oral epithelial cells. | the ability of streptococcus mutans, streptococcus sanguis, streptococcus mitis, and streptococcus salivarius to adhere to keratinized versus nonkeratinized human oral epithelial cells was compared. s. mitis and s. salivarius exhibited significantly greater adherence to keratinized cells than to nonkeratinized cells. s. mutans and s. sanguis adhered equally well to either epithelial cell type. it is concluded that keratinization of epithelial cells may be a significant factor in the adherence of ... | 1980 | 6155336 |
| effects of molecular weight of dextran on the adherence of streptococcus sanguis to damaged heart valves. | dextran-producing streptococci such as streptococcus sanguis are the organisms most frequently associated with infective endocarditis in humans. a series of experiments was designed to study how the molecular weight of dextrans affects the adherence of an endocarditis strain of s. sanguis to canine heart valves covered with platelets and fibrin. the data indicated that this adherence was dependent on dextrans of high molecular weight, such as dextran t-2000 or glucans isolated from s. sanguis or ... | 1980 | 6156909 |
| nutritionally deficient streptococcus: investigation of the hidden culprit in culture-negative endocarditis. | subacute bacterial endocarditis in a 72-year-old woman was found to be caused by nutritionally deficient ("satelliting") streptococcus sanguis. the organism, which required pyridoxal compounds or thiol substitutes, was identified after the application of relatively unusual but simple laboratory procedures. normally, the organism's nutritional requirements would be fulfilled by components of the human blood that are used to inoculate clinical blood cultures, provided that the dilutional effect of ... | 1980 | 6160620 |
| bacterial adherence in endocarditis: interaction of bacterial dextran, platelets, fibrin, and antibody. | | 1980 | 6163197 |
| dextransucrase: acceptor substrate reactions. | | 1981 | 6167205 |
| dextransucrase: donor substrate reactions. | | 1981 | 6167206 |
| positive coooperativity in the binding of streptococcus sanguis to hydroxylapatite. | the adherence of streptococcus sanguis to hydroxylapatite beads has been analyzed by binding isotherms, langmuir isotherms, and scatchard plots. for saliva-coated beads, the scatchard curves contained components with both positive and negative slopes. the results are interpreted as evidence for positive cooperativity in the binding process. although all scatchard curves were similar in shape, distinct differences were observed between saliva samples from different individuals. salivary agglutini ... | 1982 | 6172378 |
| effect of gramicidin d on the acidogenic properties of oral streptococci and human dental plaque. | the effect of gramicidin d, gramicidin s, and carbonylcyanide p-trifluoromethoxyphenyl hydrazone on the glycolysis of various oral streptococci was investigated. gramicidin d was the most effective and inhibited the glycolysis of all the streptococci studied in the presence of the most common sugars found in man's diet (sucrose, lactose, glucose, and fructose). a concentration of 2.5 x 10(-6) m gramicidin d was sufficient to decrease significantly the rate of glycolysis of human dental plaque in ... | 1982 | 6177722 |
| antigenic determinant of the lancefield group h antigen of streptococcus sanguis. | previous studies indicated that the teichoic acid isolated from strains of streptococcus sanguis was group specific and defined the lancefield group h streptococci. to determine the specific antigenic determinants, the antigen was extracted from a group h streptococcus (atcc 903) by the phenol-water method and purified by column chromatography. the isolated antigen had a glycerol/phosphate/glucose molar ratio of 1:0.9:0.3; the lipid concentration was 7.6% of its dry weight. no nucleic acids were ... | 1982 | 6185428 |
| characterization of a galactose-specific lectin from actinomyces viscosus by a model aggregation system. | a simple model system has been developed in which lectin-mediated aggregation of glycoprotein-coated beads can be monitored by following the decrease in light scattering at 650 nm. aggregation has been characterized with the lectin of actinomyces viscosus t14v. its dependence on ph, temperature, and stirring rate was examined, and the number of bacterial cells in relation to the number of latex beads resulting in optimal aggregation was established. this system has the advantage of permitting th ... | 1982 | 6185429 |
| purification and immunochemical characterization of streptococcus sanguis serotype i carbohydrate antigen. | the serotype-specific antigen of streptococcus sanguis st3 (serotype i, biotype a) was extracted, chromatographically purified, and characterized by immunological and chemical methods. the antigen was extracted from purified cell walls with hot trichloroacetic acid, followed by ion-exchange chromatography on a deae-sephadex a-25 column and gel filtration through a sephadex g-100 column. a peak fraction was obtained that gave a single precipitin band when reacted with anti-type i serum. the type ... | 1983 | 6187682 |
| aggregation of human platelets and adhesion of streptococcus sanguis. | platelet vegetations or thrombi are common findings in subacute bacterial endocarditis. we investigated the hypothesis that human platelets selectively bind or adhere strains of streptococcus sanguis and streptococcus mutans and aggregate, as a result, into an in vitro thrombus. earlier ultrastructural studies suggested that aggregation of platelets over time by staphylococcus aureus was preceded in order by adhesion and platelet activation. we uncoupled the adhesion step from activation and agg ... | 1983 | 6188697 |
| construction of plasmid vectors for gene cloning in escherichia coli and bacillus subtilis. | the construction and some properties of new hybrid plasmids which are able to replicate in both escherichia coli and bacillus subtilis are presented. a 5.5 md hybrid plasmid pjp9 was constructed from pbr322 (tc, ap) and pub110 (nm) plasmids. pim1 (7.0 md) and pim3 (7.7 md) plasmids are its different erythromycin resistant derivatives. tetracycline, ampicillin, neomycin and possibly erythromycin resistance genes are expressed in e. coli while neomycin and erythromycin resistance genes are express ... | 1982 | 6189371 |
| an improved method for measuring aggregation of certain streptococcal bacteria found in dental plaque. | various cells were incubated with either dextran or sucrose and the reaction was terminated by the addition of a 20 per cent solution of formaldehyde. a reaction mixture consisting of cells and aggregated cells was applied to a step-gradient glycerol column (0-60 per cent) and 0.5 ml fractions were collected from the bottom of the column. non-aggregated cells remained in the top layer of the column. aggregated cells settled in the 30 per cent glycerol layer as determined by either spectrophotome ... | 1983 | 6190471 |
| effects of mecillinam and cefoxitin on growth, macromolecular synthesis, and penicillin-binding proteins in a variety of streptococci. | although some strains of streptococci seem to be virtually inert to mecillinam, the growth of other strains, notably certain viridans streptococci (streptococcus mutans and streptococcus sanguis) was inhibited by relatively low concentrations of the drug. inhibition of the synthesis of peptidoglycan, rna, protein, and dna in two tolerant strains, s. mutans fa-1 and gs-5, was studied over a wide range of concentrations of mecillinam, benzylpenicillin, and cefoxitin. the responses of both strains ... | 1983 | 6191654 |
| effects of local immunization of hamsters with glucosyltransferase antigens on infection with streptococcus sanguis. | the effects of immunization with antigens of the streptococcus mutans glucosyltransferase (gtf) complex on oral challenge with two streptococcus sanguis strains (h7pr3 and 34) in hamsters were studied. antisera to s. mutans gtf complex were able to inhibit one-third (strain h7pr3) to one-half (strain 34) of the s. sanguis gtf activity which could be inhibited when these s. sanguis gtfs were incubated with antisera to s. sanguis gtf. washed, intact cells of strains h7pr3 and 34 were able to remov ... | 1983 | 6194115 |
| surface-located trypsin-activated streptococcus sanguis strain wicky endonuclease. | a new streptococcus sanguis strain wicky endonuclease was isolated, purified and partially characterized. this nuclease acts preferentially on thermally denatured dna, is not inhibited by rna and is activated 3-5 times by trypsin. this activation is accompanied by the reduction of molecular weight of the enzyme. these features distinguish the new s, sanguis nuclease from the 3 previously described s. sanguis endonucleases. with covalently closed circular plasmid dna, the enzyme causes first the ... | 1983 | 6198873 |
| role of granulocytes in the induction of an experimental endocarditis with a dextran-producing streptococcus sanguis and its dextran-negative mutant. | the role of granulocytes in the induction of endocarditis with a dextran-producing streptococcus sanguis and a dextran-negative mutant of this strain was studied. the number of colony-forming units of streptococcus sanguis needed to colonize the vegetations in 50% of the rabbits (id50) was significantly lower for the parent strain than for the dextran-negative mutant. however, in granulocytopenic rabbits the id50s of both strains did not differ measurably. dextran-negative streptococci were more ... | 1984 | 6201185 |
| non-protein-bound iron within bacterial cells and the action of bleomycin. | damage to dna by bleomycin in vitro is entirely dependent on the presence of an iron salt and molecular oxygen. this same reaction has been used to measure non-protein-bound iron in different bacterial species. although several of the species examined were insensitive to the toxic effects of bleomycin, they all contained a concentration of non-protein-bound iron which should have been sufficient to allow iron-dependent damage to dna. other factors such as permeability or inactivation of the drug ... | 1984 | 6206867 |
| adp-like platelet aggregation activity generated by viridans streptococci incubated with exogenous atp. | to explore the possibility that streptococcus sanguis aggregation of platelet-rich plasma (prp) might be mediated by soluble agents, we tested cell-free s. sanguis supernatant for aggregation activity. the supernatant of untreated s. sanguis was without measurable prp aggregation activity. in contrast, the cell-free supernatant of atp-incubated s. sanguis produced an immediate wave of prp aggregation. the supernatant with prp aggregating activity contained insufficient protease to produce a resp ... | 1983 | 6219955 |
| degradation of the microbial and salivary components participating in human dental plaque formation by proteases elaborated by plaque bacteria. | twenty-eight strains of facultative, gram-positive, sporulating bacilli which produce caseinolytic enzymes were isolated from human early dental plaque. a major component of the extracellular caseinolytic enzymes elaborated by strong producers seemed to be neutral zinc proteases. the extracellular proteases inactivated glucosyltransferase of streptococcus mutans and inhibited the synthesis of adherent glucans from sucrose. the enzymes also degraded the strep. mutans cell-surface receptor for dex ... | 1983 | 6222727 |
| inhibition by acarbose, nojirimycin and 1-deoxynojirimycin of glucosyltransferase produced by oral streptococci. | acarbose is known to inhibit glucoamylase, maltase and sucrase. our aim was to test whether it would also inhibit glucosyltransferase (gtf), to determine the type of inhibition and to compare the inhibitor potency of acarbose with that of nojirimycin and deoxynojirimycin, two other glucosidase inhibitors. enzyme inhibition was measured either by chemical assay or by incorporation of radioactivity into product. acarbose effectively inhibited the synthesis of polysaccharide by gtf from strains of ... | 1983 | 6226260 |
| inhibition of the synthesis and secretion of extracellular glucosyl- and fructosyltransferase in streptococcus sanguis by sodium ions. | the influence of na+ and k+ on the synthesis and secretion of extracellular glucosyltransferase (gtf; ec 2.4.1.5) and fructosyltransferase (ftf; ec 2.4.1.10) by streptococcus sanguis nctc 7865 and streptococcus sanguis challis nctc 7868 has been determined. no ftf and little or no mutansucrase (gtf-i) activities were detectable during growth on glucose or sucrose unless the na+/k+ ratio of the cultures was kept low. increasing k+ concentrations stimulated the production of ftf and dextransucrase ... | 1984 | 6231355 |
| the origin and composition of multiple forms of dextransucrase from streptococcus sanguis. | multiple forms of purified dextransucrase have been observed in the presence of low detergent concentrations ( luzio , g.a., grahame , d. a. and mayer, r.m. (1982) arch. biochem. biophys. 216, 751-757). we now show these forms to arise partly as a result of proteolysis, and partly due to incomplete dissociation of the enzyme. upon 25 degrees c incubation of the crude enzyme, several new bands appeared with little or no change in total activity. the electrophoretic pattern of aged, crude enzyme w ... | 1984 | 6231957 |
| exogenous thymidine and reversal of the inhibitory effect of sulfamethoxazole-trimethoprim on streptococci. | the practice of using sulfamethoxazole-trimethoprim (sxt) for the selective isolation of streptococcus pyogenes and as a taxonomic character in the presumptive identification of streptococci was applied to 17 strains of different groups of streptococci to determine their characteristic behaviour in the presence of exogenous thymidine. streptococcus pyogenes, streptococcus agalactiae and group d enterococci utilized thymidine, the first two species obtaining a maximum reversal of the inhibitory e ... | 1984 | 6238821 |
| purification and properties of deoxyribonucleic acid binding factor isolated from the surface of streptococcus sanguis cells. | deoxyribonucleic acid (dna) binding factor (bf) was found in surface fluids from competent and noncompetent cells of streptococcus sanguis strains challis, wicky, and blackburn. fluids from noncompetent cells exhibited about 10% bf activity compared with extracts from competent cells. bf from competent wicky cells was purified to homogeneity by electrophoresis and immunodiffusion. purified bf preparations exhibited slight endonucleolytic activity, directed mainly against single-stranded dna. nuc ... | 1980 | 6245057 |
| rate-limiting steps of the glycolytic pathway in the oral bacteria streptococcus mutans and streptococcus sanguis and the influence of acidic ph on the glucose metabolism. | | 1980 | 6249251 |
| chimeric streptococcal plasmids and their use as molecular cloning vehicles in streptococcus sanguis (challis). | chimeric plasmids, which were useful as cloning vehicles in a streptococcus sanguis (challis) host vector system, have been constructed. by using three different strategies of restriction endonuclease digestion and ligation, a deoxyribonucleic acid (dna) fragment bearing an erythromycin resistance determinant was ligated in vitro to a phenotypially cryptic plasmid from streptococcus ferus. recombinant plasmids could be recovered after transformation of s. sanguis (challis) with these preparation ... | 1980 | 6251030 |
| molecular cloning of an erythromycin resistance determinant in streptococci. | the erythromycin resistance determinant of plasmid pdb102, a derivative of plasmid psm19035, was cloned into the single hindiii site of the 3.6-megadalton cryptic streptococcus mutans plasmid pva318 and introduced into streptococcus sanguis strain challis by transformation. plasmid pdb201, which was isolated from one of the transformants, consisted of the vector plasmid and the 1.15-megadalton hindiii fragment d of psm19035. hindiii fragment d contained within it one of the two unique "spacer" s ... | 1980 | 6253443 |
| utilization of hydroxyapatite adsorbable salivary proteins as growth substrates for plaque-forming oral streptococci. | following treatment with hydroxyapatite, clarified mixed saliva from one donor source lost much of its growth-supportive activity for s. mutans va-29r (type c). growth of the organism in a basal medium containing proteins desorbed from ha with 0.067 m potassium phosphate buffer, ph 8.0, was accompanied by the disappearance of some of the proteins, including those with isoelectric points of 4.90, 5.72, and 6.00. these proteins are among those known to be specifically attacked by s. mutans. these ... | 1981 | 6268674 |
| molecular cloning in streptococci: physical mapping of the vehicle plasmid psm10 and demonstration of intergroup dna transfer. | the streptococcal resistance plasmid psm10 (8.3 kb), a deletion derivative of psm10419 (22.9 kb) determining constitutive erythromycin and lincomycin resistance, was physically mapped with the restriction endonucleases avai, avaii, ecori, hpai, kpni, pvuii (one site each), hindiii, haeii (three sites each), hincii (four sites), and hhai (five sites). using the cryptic plasmid pva318 as cloning vehicle, the largest hindiii fragment of psm10 (3.3 kb) was shown to contain the erythromycin/lincomyci ... | 1981 | 6268942 |
| isolation of a protein-containing cell surface component from streptococcus sanguis which affects its adherence to saliva-coated hydroxyapatite. | the isolation and partial characterization of a protein-containing cell surface component from streptococcus sanguis which blocks the adherence of this microbe to saliva-coated hydroxyapatite are described. several methods of extraction were attempted. sonication of whole cells and cell walls proved to be the most successful and yielded biologically active adherence-blocking components. the adherence-blocking ability of these components was effective in intraspecies blocking experiments. the ext ... | 1981 | 6273317 |
| chemostat studies of the effect of environmental control on streptococcus sanguis adherence to hydroxyapatite. | streptococcus sanguis is a major component of early dental plaque. the ability of s. sanguis to adhere to salivary pellicle appears to involve specific bacterial surface receptors. the nature of these receptors is still not known; however, the component molecules may be subject to environmental control as has been shown for teichoic acids and certain proteins. to study these environmental effects, a chemostat was employed to vary the growth conditions of streptococcus sanguis strain g9b. this st ... | 1982 | 6274803 |
| characteristic differences between saliva-dependent aggregation and adhesion of streptococci. | comparison of saliva-mediated aggregation of streptococcus sanguis, streptococcus mitis, and streptococcus mutans and adhesion of these organisms to saliva-coated hydroxyapatite showed that there was no relationship between these two activities. adsorption of salivary aggregating activity to bacteria appears to have little effect on the ability of the residual saliva to support adherence; conversely, adsorption of salivary adherence factors to hydroxyapatite does not affect aggregation. although ... | 1982 | 6274804 |
| location of antibiotic resistance determinants, copy control, and replication functions on the double-selective streptococcal cloning vector pgb301. | the physical map of the streptococcal cloning vector pgb301 (9.8 kb) has been extended by localizing the cleavage sites of restriction endonucleases avaii, avai, bcli, bsteii, and pvuii. the latter four enzymes cleaved pgb301 at unique sites. insertion of chromosomal dna from staphylococcus aureus strain 3ar-m- into the single bsteii site of pgb301 led to inactivation of the plasmid's chloramphenicol resistance determinant. twelve deletion derivatives of pgb301 were isolated either by in vitro m ... | 1981 | 6278245 |
| molecular cloning in the streptococci. | | 1982 | 6279083 |
| oxygen toxicity in streptococcus sanguis. the relative importance of superoxide and hydroxyl radicals. | streptococcus sanguis, whose growth appears to be independent of the availability of iron, makes no hemes, contains neither catalase nor peroxidase, and can accumulate millimolar concentration levels of h2o2 during aerobic growth. it possesses a single manganese-containing superoxide dismutase whose concentration can be varied over a 50-100-fold range by manipulating the availability of oxygen during growth. cell extracts contain a soluble nadh-plumbagin diaphorase which mediates o2- production ... | 1982 | 6279624 |
| transformation of streptococcus sanguis (challis) by linear plasmid molecules. | the streptococcal erythromycin resistance plasmid psm9 was used to study the problem of how the transforming activity of mixtures of two unique linear products of restriction enzyme digestion depends on the distance between the cleavage sites. in transformation of the challis strain of s. sanguis, the transforming activity of mixed digests increased with increasing relative distances (x) between the restriction sites, where 0 less than or equal to x less than or equal to 0.5. to explain the expe ... | 1982 | 6285148 |
| helper plasmid cloning in streptococcus sanguis: cloning of a tetracycline resistance determinant from the streptococcus mutans chromosome. | a model system for testing the helper plasmid cloning system of gryczan et al. (mol. gen. genet. 177:459-467, 1980) was devised for the streptococcus sanguis (challis) host-vector system. in this system, linearized pva736 plasmid efficiently transformed an s. sanguis (challis) host containing a homologous plasmid, pva380-1, but did not transform a plasmidless host or a host containing a nonhomologous plasmid, pva380. in addition, whereas monomeric circular pva736 transformed a plasmidless host w ... | 1982 | 6288658 |
| effect of streptococcal cell wall components on bone metabolism in vitro. | cell was components from streptococcus mutans nctc 10449 and streptococcus sanguis atcc 10558 stimulated the release of 45ca from prelabeled mouse calvariae in organ culture. bone resorbing activity was not blocked by fetal calf serum. it was, however, blocked by calcitonin, an inhibitor of osteoclast-mediated bone resorption. indomethacin, a prostaglandin synthetase inhibitor, partially blocked endogenous but not antigen-stimulated 45ca, suggesting that antigen-stimulated bone resorption was no ... | 1982 | 6291729 |
| hydrophobic interactions and the adherence of streptococcus sanguis to hydroxylapatite. | streptococcus sanguis demonstrated a high affinity for hydrocarbon solvents. when aqueous suspensions of the organism were mixed with either hexadecane or toluene, the cells tended to bind to the nonaqueous solvent. increases in temperature resulted in a greater affinity of cells for hexadecane. interaction between the cells and hexadecane was also enhanced by dilute aqueous sodium chloride and by low ph (ph less than 5). the results suggest that the cell surface of s. sanguis has hydrophobic pr ... | 1982 | 6292108 |
| a cloning vector able to replicate in escherichia coli and streptococcus sanguis. | a plasmid that is able to replicate in both escherichia coli and streptococcus sanguis has been constructed by the in vitro joining of the pacyc184 (cmr tcr) and pva749 (emr) replicons. this plasmid, designated pva838, is 9.2 kb in size and expresses emr in both e. coli and s. sanguis. its cmr marker is expressed only in e. coli and may be inactivated by addition of dna inserts at its internal ecori or pvuii sites. the pva838 molecule also contains unique sali, sphi, bamhi, nrui and xbai cleavag ... | 1982 | 6295886 |
| [clinical trial of cefmenoxime in children]. | cefmenoxime (cmx) was intravenously administered to 20 children with the following bacterial infection; pneumonia in 14 cases, purulent meningitis in 2 cases, pyothorax in 2 cases, urinary tract infection in 1 case and brain abscess in 1 case. the daily dosage administered in meningitis, pyothorax and brain abscess ranged from 145-311 mg/kg/day, from 43-88 mg/kg/day in other bacterial infections. the therapeutic efficacy was excellent in 15, good in 3, poor in 2 patients, efficacy rate being 90% ... | 1982 | 6302340 |
| a factor from actinomyces viscosus t14v that specifically aggregates streptococcus sanguis h1. | a highly specific aggregation factor for streptococcus sanguis h1 (afh1) was obtained by lysozyme treatment of actinomyces viscosus t14v. at 1 micrograms/ml, afh1 aggregated a suspension of s. sanguis h1, with which a. viscosus t14v coaggregates by a mechanism not inhibited by lactose: even at much higher levels afh1 caused little or no aggregation of streptococci from other coaggregation groups (j. o. cisar et al., infect. immun. 24:742-752, 1979). the most active fraction of afh1 obtained by g ... | 1983 | 6303957 |