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peptide utilization by oral streptococci.streptococcus mitis atcc 903 and streptococcus sanguis 804 could utilize large peptides present in proteose peptone as their sole source of nitrogen but grew poorly in amino acid medium. by contrast, streptococcus mutans bht and s. mutans ib grew in amino acid medium but could not utilize large peptides. streptococcus sp. strain bravato had requirements for both peptides and amino acids. peptide size did not seem important for the utilization of peptides by s. mitis except that dipeptides were n ...19846363292
effect of saliva on coaggregation of oral actinomyces and streptococcus species.human oral actinomyces and streptococci that exhibit specific coaggregation patterns when the cells are suspended in buffer were tested for their ability to coaggregate in saliva. of 53 paired combinations of actinomyces (actinomyces viscosus, a. naeslundii, or actinomyces sp. wva 963) and streptococci (streptococcus sanguis or s. morbillorum) that exhibited coaggregation in buffer, all but 4 pairs also coaggregated when suspended in saliva. twenty-four pairs exhibited lactose-inhibited coaggreg ...19846370861
adherence of streptococcus sanguis to saliva-coated hydroxyapatite: evidence for two binding sites.the characteristics of bacterial adherence to saliva-coated hydroxyapatite were examined for a salivary aggregating strain of streptococcus sanguis, strain 12, and for its nonaggregating variant, strain 12na. both strains were found to adhere in similar numbers to saliva-coated hydroxyapatite that had been preincubated at 4 degrees c overnight. preincubation of saliva-coated hydroxyapatite overnight at 37 degrees c reduced subsequent adherence of s. sanguis 12 by approximately 10%, whereas adher ...19846319287
physical and genetic analyses of streptococcal plasmid pam beta 1 and cloning of its replication region.plasmid pam beta 1, originally isolated from streptococcus faecalis ds5, mediates resistance to the mls (macrolide, lincosamide, and streptogramin b alpha) group of antibiotics. a restriction endonuclease map of the 26.5-kilobase (kb) pam beta 1 molecule was constructed by using the enzymes avai, hpaii, ecori, pvuii, kpn1, bsteii, hpai, hhai, and hindiii. a comparison of this map to those of four independently isolated deletion derivatives of pam beta 1 located the mls resistance determinant wit ...19846319361
microbial pathogenicity in oral soft tissue diseases.recent work implicating microbial factors in the pathogenesis of several oral soft tissue diseases is discussed. these conditions include recurrent aphthous ulceration, oral cancer, sjogren's syndrome, and the oral lesions of aids (the acquired immune deficiency syndrome). this paper reviews some recent work on these topics, with emphasis on investigations in our laboratory.19846321576
optimization of an hydroxyapatite adhesion assay for streptococcus sanguis.previous studies have compared the adhesion of [3h]thymidine-labeled streptococcus sanguis to saliva-coated hydroxyapatite (sha) and buffer-coated hydroxyapatite (ha) beads. although the hypotonic buffer used in these assays was adjusted to simulate saliva, it does not necessarily provide the optimal parameters for the quantitative estimate of adhesion under in vitro conditions. optimization is necessary to provide the maximum sensitivity of the assay for detecting the effects of various salivas ...19846325348
[effect of solid substrates of microbial colony development].bacteria have been found to grow differently at contact sites to both organic and anorganic solids as on pure agar media. of 16 ad hoc selected bacterial strains, the following species (arranged in decreasing order) responded with stronger colony formation: bacillus subtilis, b. cereus, streptococcus sanguis, s. saprophyticus, s. faecalis, escherichia coli, micrococcus flavus, actinomyces viscosus, veillonella sp., enterobacter liquefaciens, yersinia enterocolitica. lactobacillus casei behaved n ...19846326398
adherence of oral streptococci: evidence for nonspecific adsorption to saliva-coated hydroxylapatite surfaces.it is proposed that binding of oral streptococci to saliva-coated hydroxylapatite (sha) surfaces is a multifactorial process involving both specific and nonspecific receptors. in this context, specific binding is described as a high-affinity, saturable interaction between the cell and binding surface. conversely, nonspecific binding is considered to be a nonsaturable, generalized, low-affinity reaction. experimental differentiation of specific binding from nonspecific binding was achieved with a ...19846327530
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 ...19846231355
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 ...19846231957
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 ...19846238821
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.19846142065
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 ...19846152366
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 ...19846201185
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 ...19846206867
adherence of oral bacteria to chemically modified hydroxyapatite. 19846317176
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 ...19846091544
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 ...19846091547
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 ...19846093974
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 ...19846094475
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 ...19846094500
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 ...19846097204
inhibition of bacterial aggregation by serum- and blood-derived proteins.human and animal sera contain potent inhibitors of saliva-mediated aggregation of oral streptococci. the inhibitors consist of a high-molecular-weight heat-labile factor and a lower-molecular-weight heat-activated factor. the latter appears to be serum albumin. analyses of purified blood-derived proteins indicated that several high-molecular-weight proteins (fibrinogen, fibronectin, and ferritin) were able to inhibit aggregation at low concentrations. these data suggest that high-molecular-weigh ...19846690411
regulation of glucose metabolism in oral streptococci through independent pathways of glucose 6-phosphate and glucose 1-phosphate formation.in vivo rates of glucose uptake and acid production by oral streptococci grown in glucose- or nitrogen-limited continuous culture and batch culture were compared with the glucose phosphorylation activities of harvested, decryptified cells. the strains examined contained significant phosphoenolpyruvate-phosphotransferase system (pts) activity, measured by a glucose 6-phosphate (g6p) dehydrogenase-linked assay procedure, but this activity was insufficient to account for the in vivo glucose uptake ...19846693352
role of granulocytes in the prevention and therapy of experimental streptococcus sanguis endocarditis in rabbits.the contributions of granulocytes to the prevention and therapy of streptococcus sanguis endocarditis with procaine benzylpenicillin (pbp) was investigated in rabbits. depletion of granulocytes by treatment with mechlorethamine appeared to have no significant effect on either the prophylactic or therapeutic activities of pbp. administration of 3,000 iu of pbp before inoculation with s. sanguis retarded the course of the endocarditis for only 24 h whether granulocytes were normal or depressed in ...19846712203
broad host range of streptococcal macrolide resistance plasmids.four macrolide-lincosamide-streptogramin b resistance plasmids transferred into 13 recipients belonging to streptococcus, staphylococcus, and listeria genera. the plasmids were stably maintained in all new hosts except streptococcus sanguis, streptococcus pneumoniae, staphylococcus aureus, and listeria innocua and were identical to those found in the corresponding donor strains.19846712204
infection caused by vancomycin-resistant streptococcus sanguis ii.a patient with bacteremia caused by vancomycin-resistant streptococcus sanguis ii is presented. this rare occurrence suggests that vancomycin may not be a completely reliable antibiotic in the treatment of infections due to viridans species of the genus streptococcus. gram-positive isolates from blood and otherwise sterile body fluids should be tested for susceptibility to vancomycin.19846732222
growth of oral streptococcus species and actinomyces viscosus in human saliva.microorganisms in dental plaque live in constant association with saliva. the role of saliva in the adherence of bacteria to the teeth and the antibacterial properties of saliva have been well investigated; less interest has been shown in the possible role of saliva as a substrate for oral microorganisms. in this study it was shown that saliva can serve as a growth medium for oral streptococcus spp. and actinomyces viscosus. the cell production of these organisms on saliva was carbohydrate limit ...19846742834
[bacteria as an etiological agent of human dental caries]. 19846589328
[a periodontologic study of bacteria in the periodontal pocket--in vitro adherence of bacteria to the metal materials of periodontal probes]. 19846590694
[coaggregation reactions between oral bacteria]. 19846591474
effect of chlorhexidine and iodine on the composition of the human dental plaque flora. 19846592041
effects of chlorhexidine, iodine, and 5,7-dichloro-8-hydroxyquinoline on the bacterial composition of rat plaque in vivo. 19846592046
[effect of professional plaque removal on the recolonization of tooth surfaces by glucan-forming streptococci]. 19846592087
immunologic profile of juvenile periodontitis. i. lymphocyte blastogenesis and the autologous mixed lymphocyte response.studies of blastogenesis of lymphocytes in culture from juvenile periodontitis (jp) patients have been inconclusive. experiments demonstrating differences in lymphocyte blastogenesis to preparations of putative periodontopathogens in jp and phytohaemagglutinin (pha) were performed. variables in the blastogenesis assay system recently reported were controlled which included using a range of cell and activator concentrations, incubation times of 3, 5 and 7 days, conical-bottomed microtest wells an ...19846592318
human neutrophil migration under agarose to bacteria associated with the development of gingivitis.in clinically healthy gingiva and increasingly with the development of inflammation, neutrophils are found in the gingival tissues and sulcus. this study evaluated the relative ability of bacteria associated with gingival health and developing inflammation to stimulate this increase in neutrophil accumulation. dialyzed bacterial sonic extracts (be) in buffer and pooled human serum (phs) from pure cultures of streptococcus sanguis. actinomyces viscosus, a naeslundii, bacteroides intermedius, fuso ...19846592328
expression of a streptokinase gene from streptococcus equisimilis in streptococcus sanguis.using recombinant dna techniques, we introduced a previously cloned streptokinase gene from streptococcus equisimilis into the challis strain of s. sanguis (group h). the gene was expressed in the new host under the control of its own promoter and the gene product had biological properties identical to authentic streptokinase. however, the molecular weight of cloned streptokinase (42 k) as expressed by s. sanguis was substantially lower than that of authentic streptokinase (47 k). since the clon ...19846593564
growth and acid tolerance of human dental plaque bacteria.pure cultures of representative strains of cariogenic and non-cariogenic plaque bacteria were assessed for their ability to initiate and maintain growth in broths, adjusted to initial ph levels of 7.0, 5.5 or 5.0, and to produce lactic acid from sucrose or glucose in resting-cell suspensions at ph 6.5, 5.0, 4.5 and 4.0. streptococcus mutans, lactobacillus casei and streptococcus faecalis showed greater acid tolerance than strains of streptococcus sanguis, streptococcus salivarius, streptococcus ...19846594096
a simple method for extracting human lymphocyte stimulants from human dental plaque bacteria of the genus actinomyces.the effect of acid concentration on the hot-acid extraction of antigens from actinomyces viscosus that stimulate human peripheral blood lymphocytes in vitro was tested. the optimum ph for release of these antigens in a soluble low molecular-weight form was ph 2.3. preliminary purification on sepharose 4b demonstrated that most of the lympho-stimulatory material (about 90 per cent) had a mol. wt of about 100,000. this partially-purified antigenic material was mainly protein. the ph 2.3 hot-acid e ...19846594104
the localization of blood-borne bacteria in instrumented unfilled and overinstrumented canals. 19846594418
partial chemical characterization and biological activities of sulphated glycoproteins isolated from in-vivo pilocarpine-stimulated secretions of rat minor salivary glands.following the incorporation of [35s]-sulphate into rats, 35s-labelled sulphated glycoproteins were isolated from the minor salivary gland secretions of pilocarpine-stimulated, immobilized animals. the secretory products were initially resolved on sepharose 4b into two major radioactive fractions, one of which appeared at the void volume and represented only 7 per cent by weight of the applied fraction. the bulk of the products were of lower molecular weight and were further resolved by deae-seph ...19846596032
[effect of sugar substitutes on the growth and acid production of 2 types of acidogenic bacteria of the oral cavity]. 19846597166
[structural and ecological aspects of subgingival microflora]. 19846597611
in-vivo dental plaque-forming ability and relative cariogenicity of the bacteria streptococcus mitis and streptococcus sanguis i and ii in mono-infected gnotobiotic rats.sixteen strains of streptococcus mitis, streptococcus sanguis i and strep. sanguis ii were tested for cariogenic potential and in-vivo plaque-forming ability in a gnotobiotic wag/rij rat test system. all strains produced far less fissure plaque in vivo than strains of streptococcus milleri or streptococcus mutans. there was less extracellular matrix around cells of strep. mitis or strep. sanguis than around strep. mutans, in the fissures. dense sheets of cells were observed only with strep. muta ...19846598361
antibacterial effects of fluoride. 19846599295
neuraminidase activity: a biochemical marker to distinguish streptococcus mitis from streptococcus sanguis.selected reference and freshly isolated strains of streptococcus mitis (mitior) and streptococcus sanguis were assayed for cell-associated neuraminidase activity by their ability to hydrolyze [3h-] sialyllactitol. a cell-associated neuraminidase was detected with s. mitis and s. sanguis serotype ii (reclassified as s. mitis) but not with s. sanguis serotypes i and iii. neuraminidase activity of s. mitis correlated with this organism's inability to hydrolyze arginine, aesculin, and few, if any, s ...19846582090
a conceptual model for the co-existence of streptococcus spp. and actinomyces spp. in dental plaque.one of the most important questions in ecology is how to explain the co-existence of the variety of physiologically related organisms in the same habitat. a model is presented for the co-existence of streptococcus species and actinomyces species in dental plaque. the hypothesis is that these organisms co-exist because they simultaneously utilize several carbon and energy substrates. the hypothesis follows from the observation that the growth yield of oral streptococci and actinomyces in saliva i ...19846583241
colonization of the subgingival area by bacteroides gingivalis.the initial event in colonization of the subgingival area by b. gingivalis is its attachment to host cells and gram-positive bacteria in pre-formed plaque. the level of b. gingivalis is partly governed by products of other plaque bacteria, especially by sanguicin. once b. gingivalis resides in its nidus and starts to proliferate, expulsion of pre-existing residents may occur, especially of attached gram-positive bacteria, through the inhibitory action of the b. gingivalis product, hematin. the b ...19846583244
inhibition of lactose-reversible adherence between actinomyces viscosus and oral streptococci by salivary components. 19846584210
factors involved in artificial caries induction by oral streptococci in extracted human teeth.this study assesses the abilities of s. mutans gs5 and bht and s. sanguis g9b to produce subsurface lesions on smooth surfaces of extracted human teeth and examines factors which might be responsible for any differences encountered. teeth were incubated in brain heart infusion broth containing 2% sucrose and a pure culture of the organism to be tested, the media being changed each day for eight days. surface and media ph's were measured. the mineral content of both the surface enamel and the sub ...19846584469
an investigation of the effects of maltose and sucrose in the diet on the microbiology of dental plaque in man.in a double-blind cross-over study, 24 dental students consumed 150 g of sucrose or maltose a day in various foods. after 15 days, plaque samples were collected from the distal surface of upper right first premolars; post-diet samples were collected four months later. the median total anaerobic count of plaque exposed to sucrose was significantly lower compared with maltose samples (p less than 0.05). glucan-producing organisms per 100 anaerobes in the sucrose samples compared with the maltose ( ...19846586127
detection of streptococcal mutants presumed to be defective in sugar catabolism.the tetrazolium method for detection of bacterial mutants defective in sugar catabolism was modified for use with streptococci. the critical factors were (i) the concentration of tetrazolium, which must be titrated to determine the optimum concentration for each species or even strain, and (ii) anaerobic incubation of tetrazolium-containing agar plates. when used with standard mutagenesis protocols, this method yielded lactose-negative mutants of nine streptococcal strains representing six speci ...19846378096
group a streptococcal peptidoglycan-polysaccharide inhibits phagocytic activity of human polymorphonuclear leukocytes.injection of sterile aqueous preparations of the peptidoglycan-polysaccharide of group a streptococci (pg-aps) produces chronic inflammation in several animal models. chronic bacterial infection may be involved in some aspects of the pathogenesis of inflammation associated with the accumulation of pg-aps. accordingly, the effect of pg-aps on human neutrophil (polymorphonuclear leukocyte [pmn]) bactericidal activity was studied with the supposition that this interaction may contribute to the infl ...19846378796
clinical, microbiological and immunological features associated with the treatment of active periodontosis lesions.clinical, microbiological and immunological factors were examined using data from a subject with periodontosis. the subject was monitored at bimonthly intervals for 26 months at 6 sites per tooth for redness, plaque, suppuration, bleeding on probing, pocket depth, and attachment level. using attachment level measurements and the tolerance method of analysis, sites with active disease and control (inactive) sites of equal pocket depth were selected. subgingival plaque samples were taken from thes ...19846386896
effect of volume of blood cultured on detection of streptococcus viridans bacteraemia.fifty eight patients undergoing dental extraction each had 45 ml blood collected. this was divided into 30 ml and 15 ml blood samples for culture. the 30 ml sample was inoculated into 120 ml nutrient broth with 0.05% liquoid and the 15 ml sample into 60 ml of identical broth so that the final dilution of blood in broth was always 1/5. bacteraemia due to viridans streptococci was found in 27 and 15 patients by culturing the 30 ml and 15 ml blood samples respectively. only one further case of stre ...19846373833
lactose transport in streptococcus mutans: isolation and characterization of factor iiilac, a specific protein component of the phosphoenolpyruvate-lactose phosphotransferase system.the transport of lactose in streptococcus mutans is mediated via an inducible phosphoenolpyruvate-lactose phosphotransferase system. this system requires for catalytic activity a membrane fraction (enzyme ii), two general proteins called enzyme i and hpr, and a soluble specific protein termed factor iiilac. this protein factor was purified from s. mutans atcc 27352 by chromatographies on deae-cellulose, hydroxylapatite, ultrogel aca 34, and phosphocellulose. the purified protein migrated as a si ...19846480107
cell surface proteins of oral streptococci.whole cells of representative strains of oral streptococci (streptococcus sanguis, s. mitis, and s. salivarius) were radiolabeled by the lactoperoxidase method of radioiodination. the labeled polypeptides obtained by extraction of whole cells with boiling sodium dodecyl sulfate were analyzed by polyacrylamide gel electrophoresis and autoradiography. of the total radioactivity, ca. 70% was released by treating whole cells with trypsin, suggesting that the labeling was confined to proteins located ...19846480109
a possible mechanism for the cellular coaggregation between actinomyces viscosus atcc 19246 and streptococcus sanguis atcc 10557.the cells of actinomyces viscosus atcc 19246 (av19246) and streptococcus sanguis atcc 10557 (ss10557) coaggregated immediately after mixing in 40 mm-tris/hcl buffer. optimal conditions were ph 7.5 in the presence of ca2+ at 0.1 mm or higher. na2 edta and its analogues, na2mgedta and na2mnedta at 7.5 mm inhibited the coaggregation. trypsin and heat treatment impaired the reactive site on av19246 cells, but not on ss10557 cells. the coaggregates, once formed, dissociated gradually during extended ...19846481336
spinal epidural abscess: an unusual complication of bacterial endocarditis.we are reporting a case of epidural abscess complicating bacterial endocarditis. to the best of our knowledge, this association has not been reported before. streptococcus sanguis was isolated from the blood. a full recovery followed surgery and antibiotic therapy. the relevant characteristics of both diseases are reviewed. no explanation for this rare association is available as yet.19846490169
longitudinal investigation of bacteriology of human fissure decay: epidemiological studies in molars shortly after eruption.in the present investigation, the proportions of streptococcus mutans, lactobacilli, streptococcus sanguis, veillonellae, and an unidentified actinomyces-like organism in dental plaque on occlusal fissures of first mandibular molars were monitored at 6-month intervals over a 3-year period in 368 children who were initially in grades 1 or 2. teeth destined to become decayed exhibited a significant increase in the proportions of s. mutans from 6 to 24 months before the diagnosis of dental decay. l ...19846500709
genetic exchange between oral streptococci during mixed growth.to determine whether oral streptococci might exchange genetic information in the oral cavity, paired transformable strains of streptococcus mutans, streptococcus sanguis and streptococcus milleri were growth together. chromosomal and plasmid-borne antibiotic resistance markers could be readily transferred from s. mutans gs-5 to s. milleri nctc 10707 or s. sanguis challis during mixed growth. however, no exchange from the latter two organisms to strain gs-5 could be detected under these condition ...19846512502
viridans streptococci in infective endocarditis: species distribution and susceptibility to antibiotics.a method for the speciation of viridans streptococci (non-groupable) is described. the major identification criteria are based on the reactions to a series of biochemical tests, including acid production in lactose, inulin, raffinose, mannitol and sorbitol, hydrolysis of arginine, esculin and na hippurate, and production of polysaccharides in 5% sucrose media. a total of 450 strains was isolated from blood cultures, 183 of which were from confirmed cases of subacute endocarditis. the latter were ...19846519085
[hydrolysis of streptococcal polysaccharides by micromycete dextranases].the effect of dextranase enzyme preparations obtained from penicillium piscarium bim g-102, penicillium funiculosum, aspergillus insuetus g-116 and aspergillus ustus on polysaccharides synthesized by cariesogenic streptococcus sanguis and streptococcus mitis was being studied. according to the data obtained dextranases from p. piscarium, p. funiculosum and asp. ustus can be considered as a promising anticarious agent.19846540443
streptococcus mutans and streptococcus sanguis in plaque from orthodontic bands and brackets. 19846587970
microbiological assessment of dental plaque on bovine enamel implants worn intra-orally in children.nine caries-active children, each from six to nine years old, wore small removable enamel implants intra-orally for four weeks as part of an effort to develop removable model systems for studying dental plaque in fissures. the implants, consisting of two enamel cubes arranged to simulate a fissural space, were cemented in box preparations in stainless steel crowns on pulpotomized primary molars. upon removal, the fissural spaces were opened to facilitate plaque harvesting. the plaque samples wer ...19846588083
the gene for type a streptococcal exotoxin (erythrogenic toxin) is located in bacteriophage t12.the infection of streptococcus pyogenes t25(3) with the temperate bacteriophage t12 results in the conversion of the nontoxigenic strain to type a streptococcal exotoxin (erythrogenic toxin) production. although previous research has established that integration of the bacteriophage genome into the host chromosome is not essential for exotoxin production, the location of the gene on the bacteriophage or bacterial chromosome had not been determined. in the present investigation, recombinant dna t ...19846389348
ability of various oral bacteria to bind human plasma fibronectin.the present study describes the ability of various oral bacteria to bind human plasma fibronectin (pfn). avid binding of 125i-pfn was found for streptococcus mutans (serotypes a to h), streptococcus sanguis, group a streptococcus pyogenes and staphylococcus aureus, while other gram-positive bacterial species tested demonstrated only weak or negligible pfn binding ability. two gram-negative bacterial species, bacteroides gingivalis and escherichia coli, did not significantly bind pfn. 125i-pfn bi ...19846390098
antibiotic susceptibility of streptococcal strains associated with infective endocarditis.seventy-six strains of various species of streptococci isolated from patients with infective endocarditis were tested for their susceptibility to 13 antibiotics by an agar dilution method. the antibiotics tested were: benzyl-penicillin, ampicillin, cefotaxime, vancomycin, erythromycin, rifampicin, pristinamycin, gentamicin, netilmicin, tobramycin, amikacin, dibekacin and streptomycin. excluding enterococci, 91% of strains were sensitive to benzylpenicillin. resistance to benzylpenicillin was onl ...19846394332
variable nature of the bacterial cell surface. 19846399205
trypsin-susceptible cell surface characteristics of streptococcus sanguis.the adherence of streptococcus sanguis to saliva-coated hydroxylapatite was markedly reduced by treatment of the cells with trypsin. in scatchard plots of adherence data, protease-treated s. sanguis did not exhibit the characteristic positive slopes, suggesting that trypsin prevented cooperative interactions between the cells and artificial pellicle. trypsin also reduced the tendency of s. sanguis to bind to hexadecane and to octyl-sepharose. when sodium dodecyl sulfate was used to elute s. sang ...19853006899
penicillin therapy for treatment of experimental endocarditis caused by viridans streptococci in animals.we studied the efficacy of penicillin and penicillin combined with streptomycin in the treatment of experimental endocarditis caused by viridans streptococci that are susceptible, tolerant, or relatively resistant to penicillin. rabbits with experimental endocarditis were treated with procaine penicillin (1.5 x 10(5) u/kg) administered twice daily or with procaine penicillin (1.5 x 10(5) u/kg) plus streptomycin (20 mg/kg) administered twice daily for five days. compared with control animals, ani ...19853846608
effect of environmental conditions on the fluoride sensitivity of acid production by s. sanguis nctc 7865.growth and environmental conditions affected the fluoride (f) sensitivity of acid production by streptococcus sanguis nctc 7865. cells grown glucose-limited in a chemostat were generally more sensitive than those harvested from cultures in which there was an excess of glucose (amino acid-limited). there was no consistent relationship between the growth rate of cells and their f sensitivity. slower-growing cells (mean generation time = 14 hr) were more sensitive than those growing quickly when gl ...19853855887
additive inhibitory effects of combinations of fluoride and chlorhexidine on acid production by streptococcus mutans and streptococcus sanguis. 19853856486
[biochemical capacity of glucan-producing cariogenic streptococci from human dental plaque with special reference to their acid-forming capacity]. 19853856517
some factors affecting the diffusion of [14c]-lactate in human dental plaque.the apparent diffusion rate, d, of lactate was significantly retarded in dental plaque fluid and a simulated plaque fluid consisting of a chemically-defined solution of salts, amino acids and albumin in phosphate buffer at ph 6.5. metabolic utilization of lactate in live plaque residue reduced d for lactate into such samples of residue, compared with killed samples. d in plaque residue was lower than in a previous study. increasing the packing density of killed plaque residue of streptococcus sa ...19853857030
the relationship between the number of the bacterium streptococcus mutans at discrete sites on the dentition of macaque monkeys (macaca fascicularis) and the subsequent development of dental caries.sixteen consecutively-born monkeys were used in a longitudinal study to determine the changes occurring in the total number of bacteria in the palatal grooves of the upper left first deciduous molar teeth, following the introduction of a sucrose-based diet. the total number of bacteria recovered from the grooves increased significantly following the diet change. twenty-nine days after the diet change, the number of streptococcus mutans had increased from a median value of less than 10(2) to appr ...19853857890
inhibition of [3h]-thymidine uptake in human gingival fibroblasts by extracts from human dental plaque, oral bacteria of the streptococcus and actinomyces species.extracts from human dental plaque, streptococcus mutans, streptococcus salivarius, streptococcus faecalis, streptococcus sanguis, actinomyces israelli and actinomyces odontolyticus inhibited [3h]-thymidine uptake by primary human gingival fibroblast cell lines as previous work has shown in respect of hela cells. the results show that a variety of oral bacteria, not usually considered to be periodontal pathogens, elaborate factors that adversely affect fibroblasts.19853857891
infectivity and natural transmission of the bacterium streptococcus mutans in monkeys (macaca fascicularis) at different ages.oral inoculation of adolescent monkeys with laboratory strains of streptococcus mutans resulted in only sporadic implantation. oral colonization of all strains, except possibly one, was not enhanced by dietary sucrose compared with glucose nor by precleaning of accessible tooth surfaces. infant animals were more susceptible to implantation by laboratory-maintained strains of strep. mutans than adolescent or adult animals. this difference was magnified when in-vivo maintained strep. mutans strain ...19853857904
effect of oral nutrient limitation of gnotobiotic rats on acidogenic properties of dental plaque formed by oral streptococci.the acid production rate of dental plaque, formed by different streptococci in gnotobiotic rats fed a high sucrose diet or starved for seven or eight days, was determined in vitro. starvation had no appreciable effect on acid production. this supports the idea that the small ph-lowering ability of plaque of caries-free or stomach tube-fed people in whom exposure of the teeth to fermentable carbohydrate is relatively low or negligible results from a change in the bacterial population rather than ...19853858302
serum antibody responses to indigenous oral mucosal antigens and selected laboratory-maintained bacteria in recurrent aphthous ulceration.sera from subjects with recurrent aphthous ulceration (rau) and control subjects were tested for relative levels of igm, igg, and iga antibodies against eight selected laboratory-maintained bacteria, including streptococcus sanguis which has been implicated in the etiopathogenesis of rau. there were no differences in relative serum antibody levels for any isotype against any bacteria between control and rau groups. rau subjects with active lesions were then paired with control subjects, and each ...19853859820
the association between dietary sucrose consumption and microbial population shifts at six oral sites in man.sucrose-related microbial population shifts were evaluated at 6 oral sites in 22 volunteers, who consumed high-sucrose diets for 21 days followed by low-sucrose diets for 21 days. culturing was performed at 0, 12, 21, 33 and 42 days of the 6-week experiment. over 50,000 microbial isolates were characterized and analysed. analysis of initial cultures showed the following site-specific microbial characteristics of the 6 sites evaluated: (1) molar fissures harboured higher levels of neisseria speci ...19853861144
the surface free energy of oral streptococci after being coated with saliva and its relation to adhesion in the mouth.contact angle measurements on layers of bacteria were used to determine the bacterial surface free energy (gamma b) of a variety of oral streptococcal strains, both without and after being coated with human whole saliva. at least four isolates of each species, either freshly isolated or laboratory strains, were used. the species streptococcus mutans, s. sanguis, and s. salivarius were homogeneous, having high surface free energies, and were not affected by saliva treatment (gamma b = 106 +/- 12 ...19853861650
[antibacterial effect of calcium hydroxide on streptococcus sanguis as the root canal medicament]. 19853862203
fatal septic shock after fine needle aspiration of a pancreatic pseudocyst.fatal septic shock due to streptococcus sanguis developed eight days after fine needle aspiration (fna) of a pancreatic pseudocyst. the pseudocyst was adherent to the transverse colon (as is often the case with pseudocysts), and contamination of cyst fluid with colonic bacteria most likely initiated the infection. the patient had not received prophylactic antibiotics, even though the needle had been observed to pass through the bowel at the time of the cat-scan-guided aspiration. although the li ...19853863438
bacteriological studies on endodontic paper points.four brands of endodontic paper points were subjected to tests for sterility, antibacterial activity, and suitability as vehicles for bacteriological sampling procedures. no brand showed growth in the sterility assay. one brand showed weak but reproducible antibacterial activity. recovery of viable bacteria after absorption into the points varied and appeared to depend both on the brand of point and on the bacterial strain used. one brand appeared ineffectual for clinical bacteriological samplin ...19853863450
effect of saliva substitutes upon binding of selected oral bacteria to hydroxyapatite. 19853865705
anaerobic and aerobic metabolism of sorbitol in streptococcus sanguis and streptococcus mitior.sorbitol-fermenting strains of streptococcus sanguis and streptococcus mitior were grown both anaerobically and in the presence of oxygen in a sorbitol-containing complex medium. washed-cell suspensions were incubated with an excess of sorbitol, and the production of lactate, formate, ethanol, and acetate was analyzed. moreover, we determined the lactate dehydrogenase and pyruvate formate-lyase activities in cell-free extracts of anaerobically grown cells. the anaerobically grown cells produced ...19853867686
fluoride uptake and fluoride resistance in oral streptococci.fluoride uptake was examined in the highly f-sensitive streptococcus salivarius strain 25975, the f-resistant mutant flr103, and the relatively insensitive s. sanguis h7pr3. f was taken up by all strains from media at neutral ph, containing 1 or 10 micrograms f/ml (0.053-0.526 mmol/l), and uptake was directly proportional to the delta ph that was maintained by the cells. the final intracellular concentrations of f in the f-resistant strains were higher than those in the f-sensitive strain. simil ...19853867687
the relationships between streptococcal species and periodontopathic bacteria in human dental plaque.the existence of antagonistic and commensal relationships between microorganisms was investigated. the predominant cultivable flora in 172 plaque samples from active and non-active sites in 32 human subjects with destructive periodontitis was determined. the presence of putative periodontopathic organisms (bacteroides gingivalis, bacteroides intermedius, bacteroides forsythus, wolinella recta, actinobacillus actinomycetemcomitans, and eikenella corrodens) in a site was correlated with the absenc ...19853868968
bacterial profiles of subgingival plaques in periodontitis.in this report over 400 subgingival plaque samples taken from over 110 patients were examined microscopically and culturally for 30 bacterial parameters. the patients could be placed into six disease categories based upon clinical criteria. the bacterial profile of each clinical category was generally distinctive of that category. periodontal patients who had been successfully treated and maintained had plaques that were populated by significantly higher proportions of streptococcus sanguis, act ...19853869648
in vitro adherence of streptococcus sanguis atcc 10556 to various dental cements. 19853880003
streptococcus-escherichia coli shuttle vector psa3 and its use in the cloning of streptococcal genes.a shuttle vector that can replicate in both streptococcus spp. and escherichia coli has been constructed by joining the e. coli plasmid pacyc184 (chloramphenicol and tetracycline resistance) to the streptococcal plasmid pgb305 (erythromycin resistance). the resulting chimeric plasmid is designated psa3 (chloramphenicol, erythromycin, and tetracycline resistance) and has seven unique restriction sites: ecori, ecorv, bamhi, sali, xbai, nrui, and sphi. molecular cloning into the ecori or ecorv site ...19853883896
coaggregation of oral bacteroides species with other bacteria: central role in coaggregation bridges and competitions.seventy-three freshly isolated oral strains representing 10 bacteroides spp. were tested for their ability to coaggregate with other oral gram-negative and gram-positive bacteria. none coaggregated with any of the gram-negative strains tested, which included capnocytophaga gingivalis, c. ochracea, c. sputigena, and actinobacillus actinomycetemcomitans. strains of bacteroides buccae, b. melaninogenicus, b. oralis, and b. gingivalis failed to coaggregate with any of the gram-positive strains teste ...19853888842
chemical properties and immunobiological activities of streptococcal lipoteichoic acids.lipoteichoic acids (ltas) were chromatographically purified from crude phenol-water extract of whole cells of some streptococcal species, which included streptococcus pyogenes sv, streptococcus mutans 6715, and streptococcus sanguis atcc 10556. among these, special attention was paid to s. pyogenes lta for analyses of chemical composition and biological activities. all lta preparations contained equimolar amounts of glycerol and phosphorus. chemical analyses showed that s. pyogenes lta contained ...19853892980
immunoelectrophoretic study of cell surface antigens from different streptococcus mutans serotypes and streptococcus sanguis.antigens prepared from culture supernatants or whole cells of several cariogenic strains were examined by immunoelectrophoresis for their crossed antigenicity, with reference to streptococcus mutans omz175, serotype f. crossed immunoelectrophoresis revealed a crossreactivity between soluble extracellular and wall associated antigens of six strains of streptococcus mutans and one strain of streptococcus sanguis. protease destroyed the immunoreactivity of crossreactive antigens. one of them was sh ...19853894343
antibiotic tolerance among clinical isolates of bacteria. 19853895353
recovery of blood-borne bacteria from human urine.recovery from the urine of organisms causing bacteraemia may depend on the bacterial species involved. the survival of the more common species of bacteria which cause bacteraemia was examined in human urine, serum and normal saline. all species survived well or grew in serum. haemophilus influenzae, streptococcus pneumoniae, streptococcus sanguis and group a streptococci were killed in all urine samples. the number of colony-forming units of staphylococcus aureus, staphylococcus epidermidis, sta ...19853897387
bacteriology in juvenile periodontitis. a review. 19853898064
expression in escherichia coli of streptococcal plasmid-determined erythromycin resistance directed by the cat gene promoter of pacyc 184.the streptococcal erythromycin resistance (emr) plasmid psm7 (6.4 kb) and the e. coli vector pacyc184 (4.0 kb) were fused at their single ecori sites to form the bifunctional chimeric plasmid psm7184 (10.4 kb) in which the emr determinant was placed under control of the chloramphenicol acetyl transferase (cat) promoter of pacyc184. in the sense orientation (orientation i) of psm7, the cat promoter directed expression of emr in the e. coli host strains 294 and db11 more efficiently than did the i ...19853900334
characterization of protein and mannan polysaccharide antigens of yeasts, moulds, and actinomycetes.antigens in coccidioidin were compared with purified subfractions via tandem immunoelectrophoresis (iep) and by a combination of advancing line and crossed iep. rocket iep was suitable for titrating the reactions and showing the relationship between column fractions. these techniques required multicomponent antisera produced by hyperimmunization over many months and by the use of known standard migration pairs. the iep variations were used to chart the development of antisera against coccidioidi ...19853916766
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