| serum antibody responses to streptococcus mutans antigens in humans systemically infected with oral streptococci. | sera from patients with subacute bacterial endocarditis (sbe) due to streptococcus mutans or other oral streptococci and from normal subjects were assayed by enzyme-linked immunosorbent assay for antibodies to defined s. mutans antigens. antibodies of igg and iga isotypes to ag i/ii and ag iii were greatly elevated in s. mutans-sbe sera, and the iga antibodies in 3 sera included both polymeric and monomeric forms. elevated igm and igg anti-lipoteichoic acid and igg and iga anti-serotype c polysa ... | 1992 | 1299798 |
| actinomyces tissue specificity may depend on differences in receptor specificity for galnac beta-containing glycoconjugates. | actinomyces naeslundii 12104 and a. viscosus ly7 were compared for receptor specificities and adherence properties because these relate to their oral colonization sites. both strains bind galnac beta-containing glycosphingolipids (gsls) in a galnac beta 1-3gal alpha oethyl-sensitive fashion but differ with respect to the number of cells bound to gsls and the effect of neighboring sugar groups on the binding. their hemagglutination and saccharide inhibition profiles confirms the existence of two ... | 1992 | 1322371 |
| restriction endonuclease-fragment polymorphisms of oral viridans streptococci, compared by conventional and field-inversion gel electrophoresis. | oral streptococci formerly classified as streptococcus sanguis or streptococcus mitis have recently been divided into four species. two additional species have also been proposed for this group. each species is genetically distinct, but they have many traits in common, which makes it difficult for clinical isolates to be identified by phenotypic tests. genotypic comparison may provide an alternative approach. this study used dna fingerprint analysis for comparison of genotypes of 21 reference st ... | 1992 | 1351484 |
| complete structure of the adhesin receptor polysaccharide of streptococcus oralis atcc 55229 (streptococcus sanguis h1). | this report describes the determination of the complete primary structure of the adhesin receptor polysaccharide of streptococcus oralis atcc 55229 (previously characterized as streptococcus sanguis h1), a gram-positive bacteria implicated in dental plaque formation. the polysaccharide was isolated from s. oralis atcc 55229 cells after deproteination, enzymatic hydrolysis, and ion exchange chromatography. it was shown to consist of rhamnose, galactose, glucose, glycerol, and phosphate, in molar ... | 1992 | 1420190 |
| the gene encoding a prevotella loescheii lectin-like adhesin contains an interrupted sequence which causes a frameshift. | we cloned and sequenced the prevotella loescheii gene plaa, which encodes a lectin-like adhesin that mediates the coaggregation of p. loescheii 1295 with streptococcus oralis 34. a probe derived from the n-terminal amino acid sequence of the purified adhesin was used to identify the plaa gene from a p. loescheii genomic library constructed in lambda gem-11. sequence analysis of plaa indicates that the initial translation product contains a 22-amino-acid leader. the reading frame of the plaa gene ... | 1992 | 1429455 |
| cloning and characterization of the bacillus subtilis hemehy gene cluster, which encodes protoheme ix biosynthetic enzymes. | mutations that cause a block in a late step of the protoheme ix biosynthetic pathway, i.e., in a step after uroporphyrinogen iii, map at 94 degrees on the bacillus subtilis chromosomal genetic map. we have cloned and sequenced the hem genes at this location. the sequenced region contains six open reading frames: pona, heme, hemh, hemy, orfa, and orfb. the pona gene product shows over 30% sequence identity to penicillin-binding proteins 1a of escherichia coli, streptococcus pneumoniae, and strept ... | 1992 | 1459957 |
| extracellular dextranase from streptococcus oralis. | a human dental plaque organism, streptococcus oralis (s. mitior), was cultivated in a dextran-free, dialysed medium, and dextranase activity was isolated from the cell-free, culture supernatant. the lyophilized, crude enzyme preparation, optimum ph 6, was subjected sequentially to anion exchange and gel filtration fast protein liquid chromatography (fplc). the dextranolytic fraction from gel filtration fplc produced a symmetrical, baseline resolved peak. the dextranolytic enzyme was purified 1,1 ... | 1992 | 1470049 |
| synergistic degradation of bovine serum albumin by mutans streptococci and other dental plaque bacteria. | mutans streptococci (streptococcus mutans and streptococcus sobrinus) exhibited low levels of proteolytic activity against the model protein substrate, fitc-labelled bovine serum albumin, when incubated alone. inclusion of other members of the dental plaque microflora in the assay usually resulted in marked increases in the degree of proteolysis and a high level of synergy. interactions between mutans streptococci and either streptococcus oralis or fusobacterium nucleatum gave rise to the greate ... | 1992 | 1555762 |
| nucleotide sequences of genes encoding penicillin-binding proteins from streptococcus pneumoniae and streptococcus oralis with high homology to escherichia coli penicillin-binding proteins 1a and 1b. | the nucleotide sequence of a 3,378-bp dna fragment of streptococcus pneumoniae that included the structural gene for penicillin-binding protein (pbp) 1a (pona), which encodes 719 amino acids, was determined. homologous dna fragments from an s. oralis strain were amplified with pona-specific oligonucleotides. the 2,524-bp s. oralis sequence contained the coding region for the first 636 amino acids of a pbp. the coding sequence differed by 437 nucleotides (27%) and one additional triplet, resultin ... | 1992 | 1624444 |
| adherence of oral streptococci to salivary glycoproteins. | we used an overlay method to study the ability of human salivary glycoproteins to serve as receptors for several strains of streptococci that colonize the oral cavity. parotid and submandibular-sublingual salivas were collected as ductal secretions, separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and transferred to nitrocellulose membranes. the resulting blots were overlaid with [35s]methionine-labeled bacteria, and salivary components to which the bacteria bound were det ... | 1992 | 1729194 |
| delineation of a segment of adsorbed salivary acidic proline-rich proteins which promotes adhesion of streptococcus gordonii to apatitic surfaces. | cells of several strains of streptococcus gordonii attached in much higher numbers to experimental pellicles formed from samples of submandibular or parotid saliva on hydroxyapatite (ha) beads than to buffer controls. the nature of the salivary components responsible were investigated by preparing experimental pellicles from chromatographic fractions of submandibular saliva obtained from trisacryl gf 2000m columns. adhesion of s. gordonii blackburn was promoted by two groups of fractions. the ad ... | 1991 | 1879920 |
| teichoic acid choline esterase, a novel hydrolytic activity in streptococcus oralis. | streptococcus oralis contains an enzyme that can remove a limited amount of choline residues when tested on purified cell walls. this activity has been identified as an esterase that exhibits some biochemical properties similar to those previously found for several lytic enzymes of s. pneumoniae and its bacteriophages. | 1991 | 1884986 |
| complete structure of the cell surface polysaccharide of streptococcus oralis c104: a 600-mhz nmr study. | specific lectin-carbohydrate interactions between certain oral streptococci and actinomyces contribute to the microbial colonization of teeth. the receptor molecules of streptococcus oralis, 34, atcc 10557, and streptococcus mitis j22 for the galactose and n-acetylgalactosamine reactive fimbrial lectins of actinomyces viscosus and actinomyces naeslundii are antigenically distinct polysaccharides, each formed by a different phosphodiester-linked oligosaccharide repeating unit. these streptococci ... | 1991 | 1888724 |
| subclass distribution of salivary secretory immunoglobulin a antibodies to oral streptococci. | the ability of specific secretory immunoglobulin a (s-iga) antibodies to inhibit bacterial colonization of mucosal surfaces may be neutralized by the activity of bacterial iga1 proteases. because of the resistance of the iga2 subclass to these enzymes, the biological effect of iga1 proteases in vivo may depend on the subclass distribution of the bacterium-specific antibodies. we have estimated the subclass distribution of s-iga antibodies in saliva samples from 13 individuals against iga1 protea ... | 1991 | 1894364 |
| effects of salivary film velocity on ph changes in an artificial plaque containing streptococcus oralis, after exposure to sucrose. | results from a computer model suggest that following exposure of dental plaque to sucrose, the rate of clearance of acids from plaque into the overlying salivary film will be greatly retarded at low film velocities. this was investigated with an in vitro technique in which artificial plaque containing s. oralis cells was exposed to 10% sucrose for one min. the ph at the proximal (p) and distal (d) undersurfaces of the plaque (0.5 or 1.5 mm thick) was then monitored during the passage of a 0.1-mm ... | 1991 | 1918572 |
| effects of salivary bicarbonate content and film velocity on ph changes in an artificial plaque containing streptococcus oralis, after exposure to sucrose. | chewing-gum stimulation of salivary flow (at the time of the ph minimum following exposure of plaque to carbohydrate) has been shown to cause a rapid increase in plaque ph. the objective of this study was to determine whether the rise in plaque ph is primarily due to the increased buffering capacity of stimulated saliva, or to the fact that an increased flow rate increases the concentration gradient for acid to diffuse from the plaque into the overlying salivary film, which will be moving at a h ... | 1991 | 1918573 |
| ecology of viridans streptococci in the oral cavity and pharynx. | recently published taxonomic studies of viridans streptococci have resulted in several changes in the nomenclature and definition of oral streptococcal species. with this background, the ecology of streptococci in the oropharyngeal cavities was reinvestigated. the results based on the examination of 1426 streptococcal isolates confirmed and extended earlier findings. apart from mature supragingival plaque, which contained a mixture of all orally encountered streptococci, each site showed a chara ... | 1991 | 1945494 |
| effects of chlorhexidine on proteolytic and glycosidic enzyme activities of dental plaque bacteria. | chlorhexidine was tested for its ability to inhibit a wide range of glycosidic and proteolytic enzyme activities produced by treponema denticola, porphyromonas gingivalis, bacteroides intermedius, actinobacillus actinomycemcomitans, capnocytophaga sputigena, capnocytophaga gingivalis, capnocytophaga orchracea, capnocytophaga sp., actinomyces viscosus, streptococcus mitior, streptococcus mutans, streptococcus sobrinus, streptococcus mitis, streptococcus anginosus, streptococcus oralis and strepto ... | 1991 | 2005230 |
| complete structure of the cell surface polysaccharide of streptococcus oralis atcc 10557: a receptor for lectin-mediated interbacterial adherence. | lectin-carbohydrate binding is known to play an important role in a number of different cell-cell interactions including those between certain species of oral streptococci and actinomyces that colonize teeth. the cell wall polysaccharides of streptococcus oralis atcc 10557, s. oralis 34, and streptococcus mitis j22, although not identical antigenically, each function as a receptor molecule for the galactose and n-acetylgalactosamine reactive fimbrial lectins of actinomyces viscosus and actinomyc ... | 1991 | 2054351 |
| effect of nutrients on defined bacterial plaques and streptococcus mutans c67-1 implantation in a model mouth. | actinomyces viscosus wvu 627, streptococcus oralis lpa-1 and veillonella dispar omz 193 were cocultured on teeth in a model mouth for 66 h. synthetic saliva containing bovine salivary glycoprotein supported bacterial growth, although the delivery of an intermittent nutrient supplement, containing 1% (w/v) glucose or sucrose, gave greater bacterial cell and viable counts. when streptococcus mutans c67-1 was super-inoculated onto 24-hour mixed plaques, it became established under all regimens, but ... | 1991 | 2059972 |
| synergistic degradation of mucin by streptococcus oralis and streptococcus sanguis in mixed chemostat cultures. | oral streptococci can grow in mucin by utilizing the oligosaccharide chains as a source of carbohydrate. the degradation of the oligosaccharides by these species is accomplished by exoglycosidase activities. in this experiment, it was investigated whether strains from different species could cooperate in the release of sugars from the mucin oligosaccharide. to this end, streptococcus sanguis ny 584 and streptococcus oralis strain ny 586 were grown continuously in a chemically-defined medium, wit ... | 1991 | 2066484 |
| association of selected bacteria with the lesions of root surface caries. | plaque from the root surfaces of 165 subjects (mean age 65.5 years, 22-26 teeth/subject) was analysed for specific bacteria. five subject groups were defined: a (dmfs 16.4), b (dmfs 55.9), c1 (dmfs 55.6), c2 (dmfs 57.0) and c3 (dmfs 48.1). groups c1 and c2 had unrestored root surface lesions; group a, b and c3 were free of unrestored root caries and differed in their coronal caries experience. streptococcus mutans was isolated more frequently from the root lesions in groups c1 and c2 than from i ... | 1990 | 2098715 |
| complete nucleotide sequences of seven eubacterial genes coding for the elongation factor tu: functional, structural and phylogenetic evaluations. | the nucleotide sequences of cloned genes coding for the elongation factor tu of seven eubacteria have been determined. these genes were from anacystis nidulans, bacillus subtilis, bacteroides fragilis, "deinonema" spec., pseudomonas cepacia, shewanella putrefaciens and streptococcus oralis. the primary structures of the genes were compared to the available sequences of prokaryotic elongation factors tu and eukaryotic elongation factors 1 alpha. a conservation profile was determined for homologou ... | 1990 | 2110445 |
| proteolytic activity of oral streptococci. | streptococcus mutans and streptococcus sobrinus were the least proteolytic of 8 species of oral streptococci while streptococcus oralis and streptococcus sanguis were the most proteolytic. degradation of fitc-bsa was significantly correlated with the hydrolysis of synthetic endopeptidase substrates. as s. oralis strains proliferate in dental plaque in the absence of dietary food their success, in vivo, might be due partially to their greater proteolytic activity compared to other oral streptococ ... | 1990 | 2182385 |
| molecular aspects of immunoglobulin a1 degradation by oral streptococci. | using a panel of 143 strains classified according to a novel taxonomic system for oral viridans-type streptococci, we reexamined the ability of oral streptococci to attack human immunoglobulin a1 (iga1) molecules with iga1 protease or glycosidases. iga1 protease production was an exclusive property of all strains belonging to streptococcus sanguis and streptococcus oralis (previously s. mitior) and of some strains of streptococcus mitis biovar 1. these are all dominant initiators of dental plaqu ... | 1990 | 2182537 |
| coaggregation of streptococcus sanguis and other streptococci with candida albicans. | thirteen strains of viridans group streptococci and two strains of other streptococci were tested for coaggregation with candida albicans. streptococcus sanguis strains generally exhibited low levels of adherence to 28 degrees c-grown exponential-phase yeast cells, but starvation of yeast cells for glucose at 37 degrees c (or at 28 degrees c) increased their coaggregating activity with these streptococci by at least tenfold. this was a property common to four c. albicans strains tested, two of w ... | 1990 | 2182544 |
| sialidase activity of the "streptococcus milleri group" and other viridans group streptococci. | viridans group streptococci were examined for the production of sialidase (neuraminidase) activity, using the fluorescent substrate 4-methylumbelliferyl-alpha-d-n-acetylneuraminic acid in a simple and rapid (15-min) assay. sialidase was produced by all strains of streptococcus oralis and s. intermedius and by a majority of s. mitis strains. s. mutans, s. sobrinus, s. gordonii, s. sanguis, s. vestibularis, s. salivarius, s. anginosus, s. constellatus, "s. parasanguis," and the "tufted fibril grou ... | 1990 | 2199505 |
| ability to bind salivary alpha-amylase discriminates certain viridans group streptococcal species. | a collection of 144 viridans group streptococcal strains recently characterized as part of a taxonomic study was examined for the ability to bind salivary alpha-amylase. this property was found in most strains of streptococcus gordonii and streptococcus mitis and in occasional strains of streptococcus anginosus and streptococcus salivarius. in contrast, all strains of streptococcus sanguis, streptococcus oralis, streptococcus vestibularis, and streptococcus mutans lacked alpha-amylase-binding ca ... | 1990 | 2254435 |
| comparison of the initial streptococcal microflora on dental enamel in caries-active and in caries-inactive individuals. | this study compared the initial (4 h) microflora on enamel in 7 caries-active and in 7 caries-inactive adolescents. in both groups the microflora was dominated by streptococci which comprised 61 and 78% (median values) of the total viable counts in caries-active and caries-inactive individuals, respectively (p less than 0.01). identification of a total of 700 streptococcal isolates according to a recently revised classification showed that the predominant streptococci belonged to the species str ... | 1990 | 2276164 |
| cohesion between oral streptococci and neisseria pharyngis on saliva-coated glass, in the presence and absence of sucrose. | ten strains of oral streptococci, comprising nine species, were screened for their in vitro cohesive interactions with a freshly isolated strain of neisseria pharyngis. strains of mutans streptococci, streptococcus salivarius, streptococcus sanguis i, streptococcus milleri and streptococcus mitis were able to cohere with n. pharyngis cells attached to a salivary pellicle adsorbed to glass. the cohesion was either due to coaggregation between the different genera or modification of the salivary p ... | 1990 | 2329945 |
| involvement of human mucous saliva and salivary mucins in the aggregation of the oral bacteria streptococcus sanguis, streptococcus oralis, and streptococcus rattus. | the contribution of human parotid (par) and submandibular/sublingual (sm/sl) saliva and of the human whole salivary mucin fraction (hwsm) to saliva-induced bacterial aggregation was studied for s. sanguis c476, s. oralis i581, and s. rattus hg 59. the mucous sm/sl saliva showed a much higher aggregation potency towards the s. sanguis and s. oralis strain than did the serous par saliva. the sm/sl saliva-induced aggregation was observed after 30 min, at 60 min followed by the par saliva-induced ag ... | 1990 | 2353808 |
| identification of atypical strains of streptococcus pneumoniae by a specific dna probe. | a specific dna probe containing a 0.65 kb fragment coding for the aminoterminal region of the major pneumococcal autolysin (amidase) was constructed, deleting the region involved in the specific recognition of cell wall choline residues. the high specificity of this probe was demonstrated in tests with streptococcus pneumoniae related species including streptococcus oralis, which contains choline in its cell wall. the probe was used to characterize pneumococcal isolates showing atypical response ... | 1990 | 2387292 |
| surface structures, co-aggregation and adherence phenomena of streptococcus oralis and related species. | seven strains of streptococcus oralis were found to possess surface structures. four strains possessed long fimbriae which ranged in length from 266-366 nm, while the remaining three strains possessed shorter peritrichously distributed fibrils which ranged in length from 80-197 nm. the fibrillar strains were morphologically similar to strains of streptococcus sanguis i and ii and streptococcus mitis. no strain of s. oralis produced tufts of fibrils like certain strains of s. sanguis i. strains o ... | 1989 | 2475745 |
| infection of streptococcus oralis nctc 11427 by pneumococcal phages. | we have found a group of pneumococcal bacteriophages (cp-1, cp-7) that can successfully infect and replicate in streptococcus oralis, whereas dp-1 was unable to infect this species. we have also developed conditions that allowed transfection of s. oralis using dp-1 dna. our results support the direct involvement of the phage-coded lysins in the liberation of the phage progeny from infected s. oralis cells. since s. oralis and s. pneumoniae are bacteria that share the same ecological niche in hum ... | 1989 | 2612885 |
| construction of a dna probe for the specific identification of streptococcus oralis. | a dna probe for the specific detection and identification of streptococcus oralis was isolated from hindii-digested dna of s. oralis nctc 11427 and cloned in escherichia coli. the plasmid pos1 hybridized only to dna of s. oralis and not to that of other viridans group streptococci. | 1988 | 2838503 |
| partial characterisation of the inhibitory substances produced by streptococcus oralis and related species. | the production of inhibitory substances was sought by deferred antagonism. streptococcus oralis, streptococcus mitis and streptococcus sanguis produced bactericidal concentrations of hydrogen peroxide, but no detectable bacteriocin. actinomycetes and neisseria pharyngis were particularly susceptible to the lethal action of hydrogen peroxide. streptococcus milleri produced bactericidal concentrations of hydrogen peroxide and bacteriocin-like substances. s. oralis strains were inhibited by the bac ... | 1988 | 3216798 |
| characterization of genetic transformation in streptococcus oralis nctc 11427: expression of the pneumococcal amidase in s. oralis using a new shuttle vector. | we have worked out conditions for the study of competence development and genetic transformation in streptococcus oralis nctc 11427 (type strain), a species that contains choline in the cell wall. the peak of competence was found at the early exponential phase of growth and the optimal conditions for transformation were achieved with shuttle plasmids prepared from s. pneumoniae or from escherichia coli serving as donor dna. transformation with dye-buoyant density gradient purified plasmid prepar ... | 1988 | 3241622 |
| a simple method for determining extracellular polysaccharide-producing ability of oral streptococci. | a simple method is described for determining the types of extracellular polysaccharides produced by oral streptococci. the method yields quantitative results in which the amount of polysaccharides produced is normalised with respect to dna. results correlate well with previously published data for oral streptococci, except in the case of streptococcus oralis for which there is no previously published data. all species within the mutans group produced both soluble and insoluble glucan; while solu ... | 1987 | 3316938 |
| relative cariogenicity and in-vivo plaque-forming ability of the bacterium streptococcus oralis in gnotobiotic wag/rij rats. | the rats, fed a high sucrose diet, were mono-infected with seven strains of streptococcus oralis. moderate levels of caries were induced by four strains, and three others induced low levels. approximal lesions were induced by two strains; no buccal/lingual lesions were produced. scanning electron microscopy showed that all strains colonized the tooth fissures, some strains producing a moderately abundant and dense plaque. the most cariogenic strains (pb178, pb180 and pb186) induced similar level ... | 1987 | 3479083 |
| streptococcus oralis previously identified as uncommon 'streptococcus sanguis' in behçet's disease. | the relation between the biochemical and serological properties of 'streptococcus sanguis' was studied to characterize the strains isolated from dental plaque of patients with behçet's disease and controls. seven reference and 100 clinical strains preserved by the behçet's disease research committee of japan were identified using established criteria and differentiated with antisera against strep. oralis atcc 10557, strep. sanguis atcc 10556 and 'strep. sanguis' st7, compatible with the criteria ... | 1995 | 7487566 |
| use of restriction fragment polymorphism analysis of rrna genes to assign species to unknown clinical isolates of oral viridans streptococci. | this study evaluated restriction fragment length polymorphisms of rrna genes (ribotyping) for genotypic identification of 53 oral isolates classified as "streptococcus sanguis" by colony morphology. isolates were from 8-h buccal plaque on lower first permanent molars of 20 subjects. dna was digested with aatii and hybridized with digoxygenin-labeled cdna of escherichia coli 16s and 23s rrna. strains were ribotyped again with alwni or pvuii on the basis of the presence or absence of a 2,290-bp aa ... | 1994 | 7512095 |
| the use of lectins in monitoring degradation of oligosaccharide chains in mucin by oral streptococci. | the ability of utilize mucin oligosaccharides as sources of carbohydrate and energy is believed to be an important mechanism in the ecology of oral streptococci. in this study we have used digoxigenin-labelled lectins of various specificities to monitor changes in the nonreducing end groups of oligosaccharide chains following their degradation by streptococcus oralis ny 586 and streptococcus sanguis ny 584. the reaction of degraded mucin with peanut lectin, that recognizes the core disaccharide ... | 1994 | 7520835 |
| determination of 16s rrna sequences of streptococcus mitis and streptococcus gordonii and phylogenetic relationships among members of the genus streptococcus. | we determined the 16s rrna sequences of the type strains of streptococcus mitis and streptococcus gordonii and calculated the phylogenetic distances between those organisms and other members of the genus streptococcus. the viridans group streptococci were separated into five phylogenetic groups; we named these groups the anginosus group, the mitis group, the salivarius group, the bovis group, and the mutans group. s. mitis and s. gordonii clustered in the mitis group together with streptococcus ... | 1995 | 7537076 |
| saliva protein binding to layers of oral streptococci in vitro and in vivo. | this paper reports a system for measuring saliva protein binding to oral streptococci. enamel chips with layers of streptococcus gordonii blackburn or streptococcus oralis 10557 were incubated in vitro with whole saliva from eight persons. blackburn bound significantly more amylase than 10557; no strain differences were seen for lysozyme or lactoferrin. there were significant correlations between saliva and bound amylase and lactoferrin. blackburn and 10557 chips were then placed in ten subjects ... | 1995 | 7543122 |
| sucrose-dependent accumulation of oral streptococci and their adhesion-defective mutants on saliva-coated hydroxyapatite. | the adhesion and accumulation of oral streptococci on saliva-coated hydroxyapatite was examined in strains representing species that appear in initial plaque (streptococcus sanguise fc1 and streptococcus oralis c5) and in more mature plaque (streptococcus gordonii g9b). washed cells of strains fc1 and c5 did not attach better to saliva-coated hydroxyapatite than did strain g9b, suggesting that the degree of initial adhesiveness does not alone account for the temporal appearance of these bacteria ... | 1995 | 7567067 |
| homeologous recombination and mismatch repair during transformation in streptococcus pneumoniae: saturation of the hex mismatch repair system. | the ability of the hex generalized mismatch repair system to prevent recombination between partially divergent (also called homeologous) sequences during transformation in streptococcus pneumoniae was investigated. by using as donor in transformation cloned fragments 1.7-17.5% divergent in dna sequence from the recipient, it was observed that the hex system prevents chromosomal integration of the least and the most divergent fragments but frequently fails to do so for other fragments. in the lat ... | 1995 | 7568071 |
| endocarditis due to streptococcus oralis in a patient with a colon tumour. | | 1995 | 7588836 |
| oral streptococci with genetic determinants similar to the glucosyltransferase regulatory gene, rgg. | the streptococcus gordonii challis glucosyltransferase structural gene, gtfg, is positively regulated by the upstream gene, rgg, the only described gtf regulatory determinant in oral streptococci. southern hybridization analyses indicated that rgg-like and gtfg-like determinants were present on the same hindiii fragment in strains of s. gordonii, streptococcus sanguis, and streptococcus oralis, whereas no rgg-like determinants were detected in mutans streptococci, streptococcus mitis, and strept ... | 1995 | 7591096 |
| prosthetic hip infection related to a dental procedure despite antibiotic prophylaxis. | a 39-year-old man with systemic lupus erythematosus who was taking corticosteroids had a prosthetic hip infection with streptococcus oralis after a dental procedure despite prophylaxis with erythromycin. the causative organism was resistant to erythromycin. for patients with prosthetic joints the literature does not support dental prophylaxis, which even if given appropriately, may fail to prevent infection. some experts advocate giving antibiotic prophylaxis to patients at high risk, although d ... | 1995 | 7600233 |
| postantibiotic effects and postantibiotic sub-mic effects of benzylpenicillin on viridans streptococci isolated from patients with infective endocarditis. | we investigated the postantibiotic effects (paes) and the postantibiotic sub-mic effects of benzylpenicillin on three strains of viridans streptococci isolated from infective endocarditis patients. the paes of benzylpenicillin on penicillin tolerant streptococcus sanguis tw-70 (0.4-3.9 h), penicillin tolerant s. sanguis tw-80 (0.3-6.3 h) and nontolerant streptococcus oralis tw-186 (0.5-3.1 h) were dependent on exposure time. the paes were not concentration dependent for s. sanguis tw-70 and s. s ... | 1994 | 7706164 |
| streptococci and actinomyces inhibit regrowth of streptococcus mutans on gnotobiotic rat molar teeth after chlorhexidine varnish treatment. | clinical studies suggest that the long-term suppression of mutans streptococci on tooth surfaces after intensive chlorhexidine therapy is mainly due to bacterial interference. other streptococci and also actinomyces naeslundii are proposed to inhibit regrowth of mutans streptococci after suppression by the agent. we have tested this hypothesis in gnotobiotic rats associated with streptococcus mutans alone, or associated with s. mutans and strains of streptococcus oralis, streptococcus sanguis, s ... | 1995 | 7728832 |
| adherence of candida albicans to a cell surface polysaccharide receptor on streptococcus gordonii. | candida albicans atcc 10261 and ca2 bound to cells of the oral bacteria streptococcus gordonii, streptococcus oralis, and streptococcus sanguis when these bacteria were immobilized onto microtiter plate wells, but they did not bind to cells of streptococcus mutans or streptococcus salivarius. cell wall polysaccharide was extracted with alkali from s. gordonii nctc 7869, the streptococcal species to which c. albicans bound with highest affinity, and was effective in blocking the coaggregation of ... | 1995 | 7729891 |
| degradative enzymes of oral streptococci. | members of the streptococcus sanguis group (ssg) and streptococcus milleri group (smg) were screened for their ability to produce glycosidase, arylamidase (peptidase), protease, dextranase and glycosyltransferase activities. species within each group produced unique patterns of activity. the most commonly produced glycosidases were beta-d-glucosidase, beta-d-galactosidase, n-acetyl-beta-d-glucosaminidase and n-acetyl-beta-d-galactosaminidase and the least commonly produced glycosidase activity w ... | 1995 | 7786231 |
| mucin-sulphatase activity of some oral streptococci. | mucin-sulphatase activity, measured using a 35s-[so4(2-)]-labelled colonic mucin substrate, was detected in whole cells of streptococci isolated from the human oral cavity. the highest levels of sulphatase activity were found in all strains of streptococcus salivarius, streptococcus mitis and in half of the strains of streptococcus mutans tested. little or no activity was detected in 9 of the 11 streptococcus oralis strains examined, in the 4 streptococcus constellatus strains, and in the 3 stre ... | 1994 | 7850844 |
| a comparison of the microbial flora in carious dentine of clinically detectable and undetectable occlusal lesions. | it is not known whether the aetiology of occlusal hidden caries lesions (hcl) is identical to that of small visible lesions (svl). previous studies of the microflora of hcl suggest that relatively few species can be isolated. the aim of the present study was to compare the bacterial composition of dentine from 10 hcl and 17 svl in a population of children aged 8-18 years. the following bacteria were identified: actinomyces spp., mutans streptococci, streptococcus sanguis, streptococcus oralis, s ... | 1995 | 7867050 |
| effect of binding of fibrinogen to each bacterium on coaggregation between porphyromonas gingivalis and streptococcus oralis. | fibrinogen inhibits the coaggregation between porphyromonas gingivalis and streptococcus oralis. in this study, we determined which bacterium interacts with fibrinogen in this inhibitory process. although preincubation of each bacterium with fibrinogen did not inhibit coaggregation, its activity was completely eliminated by the addition of protease inhibitors such as n-ethylmaleimide (nem), p-chloromercuriphenyl sulfonate and n alpha-p-tosyl-l-lysine chloromethyl ketone to the preincubation mixt ... | 1994 | 7870471 |
| kinetics of lactose-reversible coadhesion of actinomyces naeslundii wvu 398a and streptococcus oralis 34 on the surface of hexadecane droplets. | most investigations of mechanisms accounting for intergeneric coaggregation have emphasized stereospecific rather than nonspecific interactions. the purpose of this investigation was to determine the relative importance of lectin-carbohydrate and nonspecific hydrophobic and ionic interactions, using a model based on strains with one of the most well understood specific coaggregation mechanisms, the lactose-reversible coaggregation of actinomyces naeslundii and streptococcus oralis. the kinetics ... | 1994 | 7870472 |
| adhesin degradation: a possible function for a prevotella loescheii protease? | prevotella loescheii pk1295 produces at least 3 proteases that are separable by isoelectric focusing. one of these proteases, an enzyme with an isoelectric point at 8.5 and an m(r) of 36,000, hydrolyzes the fimbria-associated adhesin on p. loescheii responsible for coaggregation with streptococcus oralis 34, as well as gelatin, casein and fibrin. the action of this protease may contribute to the detachment of p. loescheii from its streptococcal coaggregation partner and provide a mechanism for b ... | 1993 | 7903444 |
| detection of streptococcus pneumoniae dna in blood cultures by pcr. | we have developed a pcr assay, with primers derived from the autolysin (lyt) gene, for the detection of streptococcus pneumoniae dna in blood cultures. the predicted fragment of 247 bp was detected in all strains of pneumococci, embracing 12 different serotypes that were tested. although dna extracted from four viridans streptococci spp. streptococcus oralis, streptococcus mitis, streptococcus sanguis, and streptococcus parasanguis) gave amplification products, these were quite different from th ... | 1994 | 7929764 |
| molecular basis of the optochin-sensitive phenotype of pneumococcus: characterization of the genes encoding the f0 complex of the streptococcus pneumoniae and streptococcus oralis h(+)-atpases. | the gene responsible for the optochin-sensitive (opts) phenotype of streptococcus pneumoniae has been characterized. sequence comparisons indicated that the genes involved encoded the subunits of the f0 complex of an h(+)-atpase. sequence analysis and transformation experiments showed that the atpc gene is responsible for the optochin-sensitive resistant (opts/optr) phenotype. our results also show that natural as well as laboratory optr isolates have arisen by point mutations that produce diffe ... | 1994 | 7934882 |
| mosaic pbpx genes of major clones of penicillin-resistant streptococcus pneumoniae have evolved from pbpx genes of a penicillin-sensitive streptococcus oralis. | penicillin-resistant clinical isolates of streptococcus pneumoniae contain mosaic penicillin-binding protein (pbp) genes that encode pbps with decreased affinity for beta-lactam antibiotics. the mosaic blocks are believed to be the result of gene transfer of homologous pbp genes from related penicillin-resistant species. we have now identified a gene homologous to the pneumococcal pbp2x gene (pbpx) in a penicillin-sensitive streptococcus oralis isolate m3 from south africa that diverged by almos ... | 1994 | 7934893 |
| changes in root canal microbiota during the development of rat periapical lesions. | periapical lesions are reproducibly induced in rats by pulp exposure and infection from the oral cavity. lesions expand rapidly between day 7 and day 15-20 (active phase), with slowed expansion thereafter. in the present study we characterized the root canal microbiota present during the active phase of lesion development in this system. the mandibular first molars of sprague-dawley rats were exposed on day 0. the teeth were extracted after 7 days (n = 10 animals) and 15 days (n = 10), and the m ... | 1994 | 7936717 |
| action of sodium fluoride on phagocytosis by systemic polymorphonuclear leucocytes. | alterations in phagocytosis appear to be important in the onset and development of periodontitis. we investigated new substances that may be of use in the treatment of periodontitis. in a preliminary study, we tested the effect of sodium fluoride on phagocytosis by circulating polymorphonuclear leucocytes (pmns) in 10 replicate assays using blood from six healthy subjects. sodium fluoride was tested at concentrations of 1.0 micron to 4.0 microns against streptococcus oralis, streptococcus mutans ... | 1994 | 7962905 |
| antigenic relationships among immunoglobulin a1 proteases from haemophilus, neisseria, and streptococcus species. | to investigate the antigenic variation and relationships of immunoglobulin a1 (iga1) proteases among different species and genera, we examined a comprehensive collection of serine type and metallo-type iga1 proteases and corresponding antisera in enzyme neutralization assays. sharing of neutralizing epitopes of metallo-type iga1 proteases from streptococcus pneumoniae, streptococcus sanguis, streptococcus mitis, and streptococcus oralis and of serine type iga1 proteases from haemophilus and path ... | 1994 | 8039886 |
| the cell wall polysaccharide of streptococcus gordonii 38: structure and immunochemical comparison with the receptor polysaccharides of streptococcus oralis 34 and streptococcus mitis j22. | as part of our ongoing investigations involving lectin-mediated adhesion among oral bacteria, the receptor polysaccharide from streptococcus gordonii 38 was isolated and characterized. carbohydrate analysis of the hydrolysed s. gordonii 38 polysaccharide by high-performance anion-exchange chromatography with pulsed amperometric detection (hpaec-pad) showed galactose (gal) (2 mol), n-acetylgalactosamine (galnac) (1 mol), rhamnose (rha) (2 mol), glucose (glc) (1 mol) and galactosamine-6-phosphate ... | 1994 | 8054717 |
| identification of viridans streptococci associated with bacteraemia in neutropenic cancer patients. | twenty-three viridans streptococcal isolates from pyrexial neutropenic patients with various malignant diseases were studied in a comprehensive identification scheme. fourteen isolates were identified as streptococcus oralis, five as s. mitis and two as s. salivarius but the remaining two could not be identified reliably. the virulence mechanisms associated with the ability of these species to survive and grow in vivo require further investigation but may involve the production of specific glyco ... | 1994 | 8114071 |
| pioneer oral streptococci produce immunoglobulin a1 protease. | as part of a longitudinal study of the relationship between bacterial colonization and the secretory immune response, 367 isolates of pioneer viridans streptococci collected from 40 breast- and bottle-fed neonates within the first month postpartum were tested for the production of immunoglobulin a1 (iga1) protease and glycosidases. fifty percent of the streptococci isolated produced iga1 protease, including all isolates of streptococcus oralis and s. sanguis, 60.7% of s. mitis biovar 1 isolates, ... | 1994 | 8188337 |
| cytokine induction by extracellular products of oral viridans group streptococci. | during an etiological study of kawasaki disease (mucocutaneous lymph node syndrome [mcls]), we found that dominant viridans streptococcal strains on tooth surfaces and in the throat of both mcls patients and non-mcls control children formed erythrogenic and biologically active, extracellular products. in this study, we demonstrated that erythrogenic culture supernatant concentrates of representative strains (two streptococcus mitis and two streptococcus oralis), when injected intravenously, indu ... | 1993 | 8225600 |
| phenotypic characterization of oral streptococci by classical methods. | the phenotypic characteristics of 215 strains of oral streptococci were compared on the basis of the results of sorbitol, raffinose and trehalose fermentation, ammonium from arginine production, aesculin hydrolysis, h2o2 production, susceptibility to 2 u bacitracin, and growth in 4% nacl solution. eleven different species were identified. among the most noteworthy findings were the low number of h2o2-producing strains of streptococcus sobrinus, the effective discrimination between streptococcus ... | 1993 | 8264436 |
| inhibition of coaggregation between porphyromonas gingivalis and streptococcus oralis by fibrinogen fragments. | the localization of regions of fibrinogen that inhibit coaggregation between porphyromonas gingivalis and streptococcus oralis was investigated. the coaggregation was inhibited by a alpha and gamma chains, but not by b beta chain. the inhibitory activity of fragment d was more potent than that of fragment e. some cyanogen bromide-treated fragments isolated from a alpha and gamma chains including the nh2-terminal 148-207 amino acid residues of a alpha chain (a alpha 148-207) and gamma 1-78 showed ... | 1993 | 8293957 |
| horizontal spread of an altered penicillin-binding protein 2b gene between streptococcus pneumoniae and streptococcus oralis. | the region encoding the transpeptidase domain of the penicillin-binding protein 2b (pbp 2b) gene of two penicillin-resistant clinical isolates of streptococcus oralis was > 99.6% identical in nucleotide sequence to that of a penicillin-resistant serotype 6 isolate of streptococcus pneumoniae. the downstream 849 base pairs of these genes were identical. analysis of the data indicates that the pbp gene has probably been transferred from s. pneumoniae into s. oralis, rather than vice versa, and sho ... | 1993 | 8354467 |
| a rare complication of dental treatment: streptococcus oralis meningitis. | a case of streptococcus oralis meningitis is reported. this followed extraction of a normal tooth during routine orthodontic treatment. no focus of infection could be demonstrated, either local to or distant from the extraction site. full recovery followed hospital admission and intravenous benzyl penicillin. | 1993 | 8357679 |
| an in vitro stimulation of the effects of chewing sugar-free and sugar-containing chewing gums on ph changes in dental plaque. | the objective of these studies was to simulate the effect of chewing sugar-free and sucrose-containing chewing gums on the return of the ph to neutrality after exposure to sucrose of plaque located on the buccal (blm) and lingual (llm) surfaces of the lower molar teeth. in study 1, a 0.5-mm-deep artificial plaque containing streptococcus oralis cells was exposed to 10% sucrose for one min, and a 0.1-mm-thick film of sucrose-free artificial saliva was then flowed over the plaque surface at the un ... | 1993 | 8408881 |
| purification and characterization of chimeric human iga1 and iga2 expressed in cos and chinese hamster ovary cells. | ag-specific chimeric human iga molecules, of the two human subclasses, iga1 and iga2, have been expressed in two mammalian cell systems. analysis of the secreted iga molecules, purified in milligram quantities from stable chinese hamster ovary transfectants by ag affinity chromatography, has allowed a direct comparison of the biologic properties of the two subclasses. hplc gel filtration analysis revealed that in both subclasses, the iga molecules associate predominantly into dimers. the monomer ... | 1993 | 8409433 |
| mixed continuous cultures of streptococcus mutans with streptococcus sanguis or with streptococcus oralis as a model to study the ecological effects of the lactoperoxidase system. | mixed continuous cultures of streptococcus species were obtained, using complex carbohydrate (mucin) as a source of nutrients, to study the ecological effects of oxygen and the lactoperoxidase system. s. mutans nctc 10449 was unable to grow as a pure culture on mucin, but attained a significant population size in the presence of s. oralis and s. sanguis strains. the cell densities of the anaerobic mixed cultures decreased when oxygen was supplied, and s. mutans was more suppressed by oxygen than ... | 1993 | 8448770 |
| possible role of a choline-containing teichoic acid in the maintenance of normal cell shape and physiology in streptococcus oralis. | streptococcus oralis atcc 35037 took up radioactively labeled choline from growth medium. most of the choline (80 to 90%) was incorporated into the cell wall teichoic acid, and about 10% was localized in the plasma membrane. while cells grew in choline-free medium, they did so at slow rates and produced cell walls with greatly reduced amounts of phosphate and no detectable choline. cells grown in choline-free medium had grossly abnormal shape and size. both biochemical and morphological abnormal ... | 1993 | 8449879 |
| oral streptococcal colonization of infants. | the objective of this study was to determine the prevalence and proportions of different streptococcal species among the streptococcal flora during infancy. a total of 60 oral samples were collected by oral swabbing of the buccal mucosa and alveolar ridges of 18 infants before tooth eruption and from buccal and lingual surfaces of teeth after tooth eruption. a total of 549 isolates on mitis salivarius agar were speciated, principally by recently revised biochemical criteria of kilian et al. stre ... | 1993 | 8510978 |
| dental plaque development on defined streptococcal surfaces. | coaggregations between bacterial species have been widely studied in vitro but not in the mouth. a new in vivo assay was used to measure the rate and composition of indigenous plaque formation onto bovine enamel chips covered with a continuous layer of bacteria. chips were covered with streptococcus oralis atcc 10557, which coaggregated with many oral species, or streptococcus gordonii s7, which did not coaggregate with these oral species, and placed in the mouth for 4 and 24 h. there were no di ... | 1993 | 8510979 |
| species of alpha-hemolytic streptococci possessing a c-polysaccharide phosphorylcholine-containing antigen. | an enzyme-linked immunosorbent assay technique was used to detect and quantify c-polysaccharide-like antigen in strains of alpha-hemolytic streptococci classified into species by following the latest taxonomic recommendations. c-polysaccharide-like antigen is found only in streptococcus oralis, s. mitis, and s. pneumoniae, which are genetically closely related. | 1993 | 8514415 |
| effects of a 12-month prophylactic programme on selected oral bacterial populations on root surfaces with active and inactive carious lesions. | in 15 caries-active patients, with a total of 770 exposed root surfaces, the effect of fluoride therapy and professional tooth cleaning was studied during a 1-year period. dental plaque from 92 of the root surfaces and whole saliva samples were analysed at baseline and after 12 months for the presence of specific bacteria. the results showed that the number of active carious lesions had decreased from 99 to 46, while the inactive lesions had increased from 69 to 124. of the active lesions which ... | 1993 | 8519057 |
| isolation and characterization of coaggregation-defective (cog-) mutants of streptococcus gordonii dl1 (challis). | streptococcus gordonii dl1 (challis) bears coaggregation-mediating surface adhesins which recognize galactoside-containing surface polysaccharides on streptococcus oralis 34, streptococcus oralis c104, and streptococcus sm pk509. fifty-nine spontaneously-occurring coaggregation-defective (cog-) mutants of s. gordonii dl1 unable to coaggregate with partner streptococci were isolated. six representative cog- mutants were characterized by their coaggregation properties with four actinomyces naeslun ... | 1995 | 8519477 |
| rhabdomyolysis associated with bacteremia due to streptococcus viridans. | a 25-year-old man was admitted with complaints of fever and macrohematuria. laboratory tests showed a substantial increase in serum creatine phosphokinase and creatinine in association with myoglobinuria and proteinuria. blood culture grew streptococcus salivarius and streptococcus oralis. findings of renal biopsy were compatible with iga nephropathy. the glomeruli had a mild mesangial proliferation without crescentic lesions. changes of the interstitium and tubules were not evident. the clinica ... | 1995 | 8563122 |
| viridans streptococci isolated from the bloodstream. relevance of species identification. | over a 4-year-period, 104 isolates belonging to the viridans streptococci were recovered from the blood and identified to the species according to beighton and co-workers. streptococcus oralis was the species most frequently recovered from patients in the hematology unit [29 of 39 (74%)]. streptococcus mitis ranked second [seven of 39 (18%)]. both species were associated with oromucositis. isolates presently identified as s. oralis are mainly those previously identified as s. mitis or streptococ ... | 1995 | 8565415 |
| defining antibody targets in streptococcus oralis infection. | immunoblotting of sera from 12 neutropenic patients with streptococcus oralis septicemia and 18 patients with endocarditis due to viridans group streptococci revealed immunodominant s. oralis antigens at 85 and 180 kda. the former cross-reacted with a mouse monoclonal antibody to hsp90. the latter was identified by sequencing positive clones obtained by screening a genomic expression library of s. oralis with pooled sera from patients who had been infected with s. oralis. antibody eluted from on ... | 1996 | 8613367 |
| effect of mucin and glucose on proteolytic and glycosidic activities of streptococcus oralis. | the production of glycosidase and protease activities, which may play a role in the degradation of human glycoproteins, by streptococcus oralis strains isolated from endocarditis, septicaemia or the oral cavity was investigated with a range of fluorogenic substrates. the ph optima of the proteases ranged from 6.0 to 9.3 and the ph optima for the glycosidases were lower (4.5-6.0), although the ph range over which both groups of enzymes acted was broad. growth in a minimal medium supplemented with ... | 1996 | 8636957 |
| bacterial 16s rdna polymerase chain reaction in the detection of intra-amniotic infection. | bacterial polymerase chain reaction (pcr) was used to detect early subclinical intraamhiotic infection. we used universal primers which amplify a dna fragment of 16s ribosomal dna (rdna) from all known bacteria and sequenced the positive samples to identify the bacterial species. | 1996 | 8688393 |
| metabolism of glycoprotein-derived sialic acid and n-acetylglucosamine by streptococcus oralis. | nine strains of streptococcus oralis, isolated from blood cultures of patients with infective endocarditis or from the oral cavity as part of the normal flora, were examined for their ability to elaborate sialidase (neuraminidase) and n-acetylglucosaminidase, enzymes which are involved in the degradation of glycoproteins. both glycosidases were induced when bacteria were grown in a minimal medium supplemented with porcine gastric mucin, a model glycoprotein, and repressed when growth occurred in ... | 1996 | 8704962 |
| experimental salivary pellicles formed on titanium surfaces mediate adhesion of streptococci. | the goal of this study was to characterize salivary components of titanium pellicles and to determine how experimental pellicles affect adhesion of several strains of streptococci to titanium surfaces. titanium experimental pellicles were formed by incubation of fresh human parotid or human submandibular-sublingual saliva on pure titanium beads. pellicle was recovered from the beads using sodium dodecyl sulfate buffer and was subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis ... | 1996 | 8803339 |
| influence of ionic strength and substratum hydrophobicity on the co-adhesion of oral microbial pairs. | co-adhesion between oral microbial pairs (i.e. adhesion of a planktonic microorganism to a sessile organism adhering to a substratum surface) has been described as a highly specific interaction, mediated by stereochemical groups on the interacting microbial cell surfaces, and also as a non-specific, critical colloid-chemical interaction. in a colloid-chemical approach, microbial co-adhesion is considered as an interplay between, amongst others, hydrophobic and electrostatic interactions. the aim ... | 1996 | 8828203 |
| bacterial adherence to the surface and isolated cell epithelium of the palatine tonsils. | bacterial adherence to the oropharyngeal epithelium is a significant factor in normal microecology, etiopathogenesis of diseases (tonsillitis, gingivitis) and possibly also induction of immune response. bacterial adhesion to human tonsillar epithelium of whole tonsils and swabs was studied by fluorescence, scanning, and transmission electron microscopy. the epithelial cell borders were well demarcated. on the apical surface of the cells there were irregular microridges. all forms of microscopy v ... | 1996 | 8831852 |
| inhibitory effects of funoran on the adherence and colonization of mutans streptococci. | funoran, a sulfated polysaccharide extracted from the seaweed gloiopeltis furcata strongly inhibited the absorption of mutans streptococci to saliva-coated hydroxyapatite (s-ha), but enhanced that of streptococcus sanguis atcc 10556 and streptococcus oralis atcc 10557. furthermore, funoran had a strong desorption activity against mutans streptococci preadsorbed to s-ha. in the presence of sucrose, the absorption of cells of streptococcus sobrinus b13, streptococcus mutans ingbritt, and s. mutans ... | 1996 | 8833135 |
| effect of dentin treatment on in vitro root tubule bacterial invasion. | in light of the in vitro s. sanguis bacterial migration observed deep into root dentin, an in vitro system was developed to determine the viability of these bacteria at the end of migration. also of interest is whether the smear layer formed during root canal instrumentation modifies migration into root dentinal tubules. forty-eight bovine root dentin samples were randomly split into two groups. group 1 dentin blocks were not instrumented and were treated with 17% ethylenediamine tetraacetic aci ... | 1996 | 8899786 |
| utilization of sialic acid by viridans streptococci. | the importance of viridans streptococci as agents of serious extra-oral diseases, including endocarditis, is now recognized. we have tested the hypothesis that the ability to utilize sialic acid as a nutrient source may play a role in the proliferation of these organisms. the type strains of the 15 presently recognized species of viridans streptococci and two clinical isolates-s. oralis (ar3), isolated from a patient with infective endocarditis, and s. intermedius (uns35), a brain abscess isolat ... | 1996 | 8906124 |
| cell surface polypeptide csha mediates binding of streptococcus gordonii to other oral bacteria and to immobilized fibronectin. | isogenic mutants of streptococcus gordonii dl1 (challis) in which the genes encoding high-molecular-mass cell surface polypeptides csha and/or cshb were inactivated were deficient in binding to four strains of actinomyces naeslundii and two strains of streptococcus oralis. lactose-sensitive interactions of s. gordonii with a. naeslundii atcc 12104 and pk606 were associated with expression of csha but not of cshb. lactose-insensitive interactions of s. gordonii with a. naeslundii t14v and wvu627, ... | 1996 | 8926089 |
| influence of temperature on the co-adhesion of oral microbial pairs in saliva. | coaggregation (interactions between two planktonic microorganisms) and co-adhesion (interactions between sessile and planktonic microorganisms) are believed to be important factors in the formation of dental plaque by many investigators, although others doubt whether coaggregation and co-adhesion occur in vivo. it is known that coaggregation and co-adhesion generally occur equally well in buffer as in saliva, but the influence of temperature on the co-adhesion of coaggregating oral microbial pai ... | 1996 | 8930585 |
| characterization of coaggregation and fibrinogen-binding by porphyromonas gingivalis. | we have examined whether the adhesin of porphyromonas gingivalis which aggregates streptococcus oralis contributes to its fibrinogen-binding. various properties of coaggregation between p. gingivalis and s. oralis were compared with those of fibrinogen-binding to p. gingivalis cells. the coaggregation activity was measured by a turbidimetric method and the fibrinogen-binding activity was determined by using 125i-fibrinogen. both the activities showed maximum values in the ph range from 5.0 to 6. ... | 1994 | 8935092 |
| identification and characterization of a protease from streptococcus oralis c104. | streptococcus oralis is among the earliest colonizers of the tooth surface during plaque formation. as such, its enzymatic activities may influence ecologic succession on the tooth surface. in the current study, we use zymograms and preparative polyacrylamide gel electrophoresis to identify and purify a protease from s. oralis (sanguis) c104. proteases from s. oralis c104 were detected in cell pellets at 133, 146 and 176 kda as clear proteolytic bands on gelatin-substrate zymograms. preparation ... | 1996 | 8941773 |
| mode of action of a lysostaphin-like bacteriolytic agent produced by streptococcus zooepidemicus 4881. | electron microscopy of zoocin a-treated sensitive streptococcus cells revealed cytoplasmic disruption and ultimately complete rupture of the cell wall. culture viability and optical density were shown to decrease rapidly and simultaneously in streptococcus pyogenes ff22 but less quickly in the relatively more resistant streptococcus mutans 10449. zoocin a was shown to cleave hexaglycine in a colorimetric cell-free microtiter assay system, and it is concluded that the killing action of zoocin a, ... | 1996 | 8953725 |
| saliva protein binding to streptococcal layers placed at different oral sites in 48 persons. | preliminary studies of 10 subjects suggested that saliva protein binding to oral bacteria might vary among oral sites. this study investigated saliva protein binding to layers of oral streptococci in an expanded sample of 48 subjects. those persons were at opposite extremes for unstimulated whole saliva amylase, siga, lactoferrin, and lysozyme in an initial screening of 128 individuals. layers of streptococcus gordonii blackburn or streptococcus oralis 10557 on enamel chips were placed on buccal ... | 1996 | 8955674 |
| effect of antibodies on the chain length and growth of streptococcus sobrinus. | passive immunization has been suggested as a method to prevent colonization of teeth by mutans streptococci. however, the mechanism of action of antibodies, both polyclonal and monoclonal, is not clear. in this study we investigated the effect of polyclonal antibodies (pabs) and a monoclonal antibody (omvu10) on the chain length and growth of streptococcus sobrinus. during growth in broth s. sobrinus formed significantly longer chains in the presence of pabs in comparison to pre-immune serum (p ... | 1997 | 8955992 |