| immunoglobulin a antibody activity to mutans streptococci in parotid, submandibular and whole saliva. | antigen extracts of 9 strains of streptococcus mutans, streptococcus sobrinus, streptococcus salivarius and streptococcus mitis were separated in acrylamide gels by electrophoresis. strains of the same genotype of mutans streptococci were found to have virtually identical sodium dodecyl sulfate-polyacrylamide gel electrophoresis patterns but differed clearly from other genotypes of mutans or with the reference strains s. salivarius and s. mitis. immunoglobulin a (iga) antibody activity to antige ... | 1992 | 1299799 |
| effects of phenytoin on dental caries and plaque in streptococcus sobrinus-infected rats. | effects of phenytoin (pht) administration on dental caries in rats infected with streptococcus sobrinus 6715 were investigated. twenty-day-old specific pathogen-free fischer male rats were infected with s. sobrinus 6715 and fed diet 2000 containing 56% sucrose with or without pht for 52 days. antibody responses against anti-s. sobrinus in serum and saliva failed to show a statistical difference between pht-treated and nontreated rats. these results indicate that pht treatment increased plaque de ... | 1992 | 1303536 |
| [detection of dna g+c mol% in taxonomy of streptococcus mutans by means of high performance liquid chromatography]. | in the present study, dna g+c mol% of 9 strains of bacteria (including 7 international standard strain, ingbritt, and 2 other strains extracted in our lab) were detected with application of high performance liquid chromatograph. the results showed that dna g+c content of s. mutans was 35-40%, s. sobrinus was 45-46%, s. cricetus was 38%, and s. rattus was 41%. the difference between s sobrinus and s. mutans was higher than 5%, which suggested that s. sobrinus should be identified as an independen ... | 1992 | 1307950 |
| viability of streptococcus mutans and streptococcus sobrinus in whole saliva with varying concentrations of indigenous antimicrobial agents. | we have studied the possible relationship between indigenous salivary antimicrobial agents, indigenous mutans streptococci and the capability of added mutans streptococci to grow in saliva. stimulated whole saliva was collected from 19 healthy donors. saliva samples were sterilized, supplemented with glucose and inoculated with streptococcus mutans or streptococcus sobrinus. the mixtures were incubated for 20 h followed by counting of viable cells. saliva samples were analysed, both before and a ... | 1992 | 1334804 |
| antimicrobial effect of a dental varnish, in vitro. | the effects of a polymer based antimicrobial releasing varnish cervitec were investigated against different gram-positive and gram-negative bacterial strains as well as a yeast using the agar diffusion inhibitory test (adt-test in vitro). as positive controls a 1% chlorhexidine gel and 1% aqueous solution of thymol and a placebo polymer varnish without active agents were employed. the test experimental varnish containing 1% chlorhexidine and 1% thymol showed antimicrobial activity against all gr ... | 1992 | 1336221 |
| mode of photocatalytic bactericidal action of powdered semiconductor tio2 on mutans streptococci. | powdered semiconductor tio2 has a photocatalytic bactericidal capacity on some kinds of bacteria, but its mechanism still remains unclear. the mode of its photocatalytic bactericidal action on the mutans group of streptococci was investigated. powdered tio2 had a bactericidal capacity on all serotypes of mutans streptococci. streptococcus sobrinus aht was mainly used for these experiments. the most effective concentration of tio2 was about 1 mg ml-1 and, at this concentration, 10(5) colony-formi ... | 1992 | 1403378 |
| mechanism of water-insoluble glucan synthesis in streptococcus sobrinus. | synthesis of water-insoluble glucan (ig) by 1,3-alpha-d-glucan synthase from streptococcus sobrinus was examined using methylation analysis. the purified enzyme was incubated with sucrose and dextran t2000 (dt2000) for a given time and only ig was harvested by centrifugation. the remaining supernatant was incubated again, and ig was obtained. by repeating the above method using the residual supernatant, we obtained 5 varieties of ig precipitated in different periods. these igs were methylated an ... | 1992 | 1408351 |
| effects of chlorhexidine-fluoride gel treatments in mothers on the establishment of mutans streptococci in primary teeth and the development of dental caries in children. | in a longitudinal 3-year study, 151 children were followed for the colonization of the primary dentition by mutans streptococci (ms) and for the development of dental caries. at the age of 1 year, the child-mother pairs were divided into three groups on the basis of the levels of ms in maternal saliva. in the experimental group, the mothers had ms levels higher than 10(5) cfu/ml, and they were given chlorhexidine (1%)-sodium fluoride (0.2%) gel treatments twice a year for 3 years. two control gr ... | 1992 | 1423442 |
| effect of gels containing stannous fluoride on oral bacteria--an in vitro study. | the purposes of this investigation were to evaluate and compare the antimicrobial effect of (1) twelve 0.4 per cent stannous fluoride (snf2) commercial products and (2) different concentrations of snf2 (range = 0.02 to 3.28 per cent). the antibacterial inhibitory effect of various snf2 gels was evaluated as to their effectiveness against oral plaque bacteria including strains of s. mutans, s. sanguis, s. sobrinus, a. viscosus, a. actinomycetemcomitans, and b. intermedius. when twelve different c ... | 1992 | 1444958 |
| an 87-kilodalton glucan-binding protein of streptococcus sobrinus b13. | an 87-kda glucan-binding protein (gbp) of streptococcus sobrinus b13 (serotype d) was isolated and purified from extracellular culture supernatant by using affinity chromatography on sephadex g-50 and elution with a guanidine hcl gradient. western blot (immunoblot) analysis showed it to be antigenically related, but not completely identical, to the 74-kda gbp of streptococcus mutans ingbritt. the 87-kda gbp has no glucosyltransferase activity. a possible role for this gbp in the cariogenicity of ... | 1992 | 1452362 |
| effects of food preservatives on growth and metabolism of plaque bacteria in vitro and in vivo. | the aims of the present study were to assess the consumption of food preservatives during the last decades, and to study the effect of the preservatives, sorbic and benzoic acid, on growth and glycolysis of oral bacteria in vitro, and on acid formation by dental plaque in vivo. five consumption reports from the central bureau of statistics of norway were used to estimate alterations in consumption of staple food containing the two preservatives. a modified broth dilution method was used to deter ... | 1992 | 1465573 |
| noncariogenicity of erythritol as a substrate. | erythritol is a sugar alcohol produced by aureobasidium sp. from glucose. it is 75-80% as sweet as sucrose and is also nonhygroscopic. the aim of this study was to evaluate this sugar substitute from a cariological point of view. erythritol was neither utilized as a substrate for the lactic acid production nor for plaque formation of mutans streptococci (serotypes a-h) and certain oral microorganisms. it was not utilized for water-insoluble glucan synthesis or cellular adherence by glucosyltrans ... | 1992 | 1468100 |
| evaluation of the cariogenic potential of the intense natural sweeteners stevioside and rebaudioside a. | stevioside and rebaudioside a, two intense natural sweeteners, that are constituents of the south american plant stevia rebaudiana, were tested for cariogenicity in albino sprague-dawley rats. sixty rat pups colonized with streptococcus sobrinus were divided into four groups and fed stevioside, rebaudioside a or sucrose added to basal diet 2000 as follows: group 1, 30% sucrose; group 2, 0.5% stevioside; group 3, 0.5% rebaudioside a, and group 4, no addition. all four groups were sacrificed after ... | 1992 | 1468101 |
| the effect of ovariectomy on dentin formation and caries in adult rats. | since acute osteoporosis is known to enhance bone remodeling and osteoid formation, it may also affect dentin apposition. we induced osteoporosis in 15-week-old wistar rats by ovariectomy and dental caries by streptococcus sobrinus infection in the presence of either a high sucrose (cariogenic) diet or a non-cariogenic diet. intact animals with the same diets served as controls. after 99 days of cariogenic challenge the rats were killed, and the success of ovariectomy was confirmed by failure to ... | 1992 | 1476050 |
| the effect of phenytoin medication on dentin apposition, root length, and caries progression in rat molars. | to determine the effect of phenytoin (pht) on dentin apposition and the rate of caries progression in dentin, 40 wistar rats were treated daily for 35 days with intraperitoneal injections of 5,5-diphenylhydantoin. twenty-eight controls received saline with ph adjusted to that of pht. one pht and one control group were fed a 43% sucrose diet, and the others a non-cariogenic pellet diet. streptococcus sobrinus was inoculated to induce caries. schiff staining was used to determine caries. the areas ... | 1992 | 1476051 |
| mutans streptococci, lactobacilli and caries prevalence in 15 to 16-year olds in göteborg. part ii. | during the fall of 1987 one hundred and fifty-five 15 to 16-year-olds were examined with regard to caries prevalence, saliva secretion rate and salivary numbers of mutans streptococci and lactobacilli. in 15% of the subjects no mutans streptococci were detected, while 17.7% carried > 10(6) colony forming units (cfu) per ml saliva. the median value was 1.8 x 10(5) cfu per ml saliva. no lactobacilli were detected in 19% of the subjects and 14.3% had > 10(5) cfu per ml saliva. the mean caries preva ... | 1992 | 1481133 |
| reduced nicotinamide adenine dinucleotide oxidase involvement in defense against oxygen toxicity of streptococcus mutans. | the growth inhibition of the streptococcus mutans group, including streptococcus mutans, streptococcus cricetus, streptococcus rattus and streptococcus sobrinus, on glucose by oxygen and the properties of reduced nicotinamide adenine dinucleotide (nadh) oxidase induced by oxygen, using a representative oxygen-tolerant strain, were examined. the growth response to oxygen varied among strains and correlated with the level of nadh oxidase activity in the cell extract. the induced synthesis of nadh ... | 1992 | 1494456 |
| dye-mediated bactericidal effect of he-ne laser irradiation on oral microorganisms. | little attention has been given to the bactericidal effect of laser irradiation, particularly using low-power energy lasers. it has been demonstrated that he-ne laser light has an inhibitory action on dental plaque. the purpose of this study was to investigate the bactericidal effect of he-ne laser irradiation on cariogenic microorganisms. the bactericidal effect was determined by the formation of a growth-inhibitory zone or by the counting of viable bacterial colonies. streptococcus sobrinus ah ... | 1992 | 1495373 |
| genetic analysis of scra and scrb from streptococcus sobrinus 6715. | a dna fragment containing scra and scrb, which encode enzyme ii of the phosphoenolpyruvate-dependent sucrose phosphotransferase system and sucrose-6-phosphate hydrolase, respectively, was isolated from a lambda gt10 genomic dna library of streptococcus sobrinus 6715. both genes were located on a 4.2-kb dna fragment which was maintained stably in escherchia coli on low-copy-number vector pgb2. the recombinant e. coli clone expressed sucrose-hydrolytic activity on macconkey agar base supplemented ... | 1992 | 1500184 |
| odontoblast-mediated regulation of the progression of dentinal caries. | osteoblasts and odontoblasts are both derived from the same mesenchymal cell line. our aim was to investigate whether the processes of bone destruction and dentinal caries are biologically similar. the working hypothesis was that after the initiation of caries in the enamel, its rate of progression in the dentine is regulated by cell-mediated factors. experimental caries was induced in the rat with a high sucrose diet combined with streptococcus sobrinus infection. both destruction of dentine an ... | 1992 | 1508887 |
| effects of tung oil on salivary viscosity and extent and incidence of dental caries in rats. | increased salivary viscosity may be associated with an increase in dental caries. in order to examine this relationship, the caries level in rats was monitored following gastric intubation with tung oil which has been shown to significantly increase salivary viscosity. tung oil intubation over an 8-week period significantly increased the salivary viscosity in rats as compared with deoinized water and corn oil intubation. the total number of carious lesions was significantly increased (p less tha ... | 1992 | 1521305 |
| sodium hypochlorite disinfection of irreversible hydrocolloid impression material. | alginate impression material is one of the most frequently used in dentistry. however, this material is susceptible to dimensional distortion during disinfection because of its hydrophilic nature. this study examined the effects of alginate disinfection using a sodium hypochlorite spray or impression immersion. spray disinfection of an alginate impression did not cause dimensional differences of the poured stone casts when compared with casts from water-rinsed controls. immersion disinfection cr ... | 1992 | 1527745 |
| natural transmission of streptococcus sobrinus in rats: saliva and serum antibody responses to colonization. | one hundred and twenty weanling rats fed diet nih 2000 that were free of streptococcus sobrinus and other mutans streptococci were employed in this study. sixty rats were inoculated orally with s. sobrinus 6715. each infected rat (donor) was paired and housed with an uninfected recipient. saliva and serum samples were collected from 24 (12 donor and 12 recipient) rats at the baseline (day 0) and from groups of 12 recipients sacrificed on days 10, 24, 38, and 52, and the level of infection with s ... | 1992 | 1531814 |
| molecular analysis of a streptococcus mutans strain exhibiting polymorphism in the tandem gtfb and gtfc genes. | streptococcus mutans ua101, which was previously demonstrated to be highly cariogenic in gnotobiotic rats, exhibited much lower water-insoluble glucan (ig) synthetic activity compared with that of s. mutans gs5 and was unable to express sucrose-dependent colonization of smooth surfaces in vitro. on the basis of southern and western blot (immunoblot) analyses, it was demonstrated that, unlike most s. mutans strains, strain ua101 contained a single copy of a gene coding for ig synthesis. the gene ... | 1992 | 1532167 |
| noncariogenicity of maltitol in specific pathogen-free rats infected with mutans streptococci. | the effect of maltitol on caries development was examined in an experimental caries system employing specific pathogen-free (spf) sprague-dawley rats. fourteen strains of oral streptococci, including mutans streptococci, did not utilize the maltitol nor produce sufficient acid to demineralize tooth enamel. furthermore, maltitol did not serve as a substrate for glucosyltransferases of either streptococcus mutans mt8148r or streptococcus sobrinus 6715 to synthesize water-insoluble glucan. maltitol ... | 1992 | 1533175 |
| on the mechanism of xylitol-dependent inhibition of glycolysis in streptococcus sobrinus omz 176. | 1. the mechanism of xylitol-dependent inhibition of glycolysis in streptococcus sobrinus omz 176 was investigated in aerobically and anaerobically grown cells. 2. glucose-stimulated glycolysis was followed polarographically, by radio-hplc-analyses of glycolytic intermediates, by measurement of atp generated, and spectrophotometric monitoring of extent of nad(p)+/nadph-status. 3. xylitol added to suspensions of s. sobrinus inhibited o2 uptake by approximately 20%, and led to a corresponding decre ... | 1992 | 1551465 |
| 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 |
| purification and properties of extracellular mutacin, a bacteriocin from streptococcus sobrinus. | mutacin mt6223, a cell-free bacteriocin produced by streptococcus sobrinus mt6223, was purified by ammonium sulphate precipitation, chromatofocusing with pbe 94 and column chromatography on sp sephadex c-25. the specific activity of the purified mutacin was increased 1950-fold with a recovery of 9.7%. the molecular mass of the purified mutacin preparation was estimated to be 6.5 kda. the mutacin activity was stable from ph 2-7, and was resistant to treatment at 100 degrees c for 20 min. it was i ... | 1992 | 1564438 |
| adhesion of mutants streptococci to glass with and without a salivary coating as studied in a parallel-plate flow chamber. | deposition and adhesion to glass with and without a salivary coating in a parallel-plate flow chamber were studied with four strains of mutans streptococci. stationary-state adhesion of the strains to uncoated glass ranged from 0.3 x 10(6) cm-2 (streptococcus rattus hg218) to 12.7 x 10(6) cm-2 (streptococcus sobrinus hg1025) and generally decreased after saliva coating of the glass. the poor adhesion found for s. rattus hg218 to both uncoated and saliva-coated glass could be due to its relativel ... | 1992 | 1573082 |
| effects of weight watchers' diet on salivary secretion rate, buffer effect and numbers of mutans streptococci and lactobacilli. | the aim of this investigation was to study how a change to the dietary regimen of the weight watchers' (ww) affected salivary secretion rate, buffer effect and number of cariogenic bacteria. thirty-three women joining the ww were saliva sampled at the evening prior the day of the start of the dietary regimen and after 4 and 8 wk on the dietary regimen. no significant changes were found regarding saliva secretion rate and buffer effect. a significant decrease of salivary numbers of mutans strepto ... | 1992 | 1574682 |
| the effects of sucralose, xylitol, and sorbitol on remineralization of caries lesions in rats. | the purpose of this study was to determine whether ingestion of sucralose, xylitol, sorbitol, or distilled water alone could enhance remineralization of early caries lesions in rats. rats were infected by streptococcus sobrinus, fed diet 2000 (ziegler brothers, gardners, pa) ad libitum for two weeks, and, in addition, were offered drinking water sweetened by sucrose (10% w/v). a group of rats terminated at this time displayed significant levels of sulcal and smooth-surface caries. the remaining ... | 1992 | 1607434 |
| latex agglutination test for detection of mutans streptococci in relation to dental caries in children. | a simple and rapid system based on a latex agglutination (la) reaction was devised for the detection of mutans streptococci in dental plaque. latex particles were sensitized with antibodies against whole cells of streptococcus mutans strains mt8148 (serotype c), mt703r (e) and omz175 (f) and strep. sobrinus strains b13 (d) and 6715 (g). these sensitized particles were agglutinated within a few minutes after addition of 1.0-10 ng serotype-specific antigen from the homologous organisms or the nitr ... | 1992 | 1622345 |
| mutans streptococci and lactobacilli in breast-fed children with rampant caries. | this study aimed to investigate the prevalence of selected components of the oral microflora in breast-fed children who developed rampant caries (resembling nursing caries) under hitherto unexplained circumstances. dental plaque and saliva samples were collected from breast-fed children, aged between 1 and 2.5 years, with and without rampant caries. mutans streptococci and lactobacilli were isolated from dental plaque of all children with rampant caries and from most caries-free children. none o ... | 1992 | 1628292 |
| a simple biochemical scheme for the differentiation of streptococcus mutans and streptococcus sobrinus. | a collection of wild-type and reference strains of streptococcus mutans and streptococcus sobrinus was compared using a set of fermentation and enzymic tests in order to establish a simple scheme for the differentiation of these two species isolated from selective media. tests for the production of acid from n-acetylglucosamine, arbutin and melibiose, and the presence of alpha-galactosidase and alpha-glucosidase activities were useful in differentiating these species. strains of streptococcus mu ... | 1991 | 1652359 |
| intracellular xylitol-phosphate hydrolysis and efflux of xylitol in streptococcus sobrinus. | the parental strain streptococcus sobrinus (streptococcus mutans atcc 27352), which is known to transport, phosphorylate and accumulate xylitol intracellularly as nonmetabolizable xylitol-phosphate (xylitol-sensitive (xs) strain) and its xylitol-resistant (xr) spontaneous mutant were used to further investigate the inhibitory action of xylitol on oral streptococci. fructose-grown xr cells did not accumulate xylitol-phosphate, indicating that the inducible fructose pts is incapable of transportin ... | 1991 | 1658712 |
| some properties of an endodextranase inhibitor from continuous cultures of streptococcus sobrinus. | cell-free filtrates of streptococcus sobrinus, cultured at low growth rate in the chemostat, contain a dextranase inhibitor that can completely inhibit the activity of s. sobrinus endodextranase. the range of conditions under which inhibition occurs, and the situations in which enzyme activity can reappear, have been examined in continuous cultures of strain 6715-13wt and the dextranase-deficient mutant 6715-13-201. a purified preparation of the inhibitor was specific for s. sobrinus dextranase, ... | 1991 | 1669445 |
| inhibitory effect of stannous fluoride and other commonly used antimicrobial agents on oral bacteria. | the purposes of this investigation were to evaluate and compare the antimicrobial effect of stannous fluoride (snf2) gel and other commonly used oral antimicrobial agents/products. the antibacterial inhibitory effect of the various agents was evaluated by their effect against oral plaque bacteria including strains of streptococcus sanguis, streptococcus sobrinus, actinomyces viscosus, actinobacillus actinomycetemcomitans, bacteroides gingivalis and bacteroides intermedius. a lawn of the specific ... | 1991 | 1681003 |
| characterization of monoclonal antibodies against glucosyltransferase synthesizing water-insoluble glucan from streptococcus sobrinus b13. | four hybrid cell lines secreting monoclonal antibodies (mcabs) against glucosyltransferase synthesizing water-insoluble glucan (gtase-i) were generated by fusion of myeloma cells (p3u1) with splenocytes from mice immunized with gtase-i from streptococcus sobrinus b13-n. cell lines 29e7, 21gc7, and 42hb8 were found to secrete an igg2a-type immunoglobulin, and 29eg, an igm-type immunoglobulin. these two isotypes of mcabs were used for the determination of the binding sites on the gtase molecule, w ... | 1990 | 1689748 |
| characterization of cross-reactive polysaccharide antigen with serotype a and d strains from streptococcus sobrinus 6715. | the polysaccharide antigen (designated si) from streptococcus sobrinus 6715 (serotype g) which cross-reacts with serotype a and d strains was purified by a specific anti-cross-reactive g-a antibody-sepharose 4b affinity column. by a double immunodiffusion analysis, the si antigen was found to lack the serotype-specific g site, but contained the cross-reactive sites g-a, g-d and g-(a-d) on a single molecule. polysaccharide si was composed of galactose, glucose and rhamnose in a molar ratio of 4.7 ... | 1990 | 1690575 |
| regions of the streptococcus sobrinus spaa gene encoding major determinants of antigen i. | surface protein antigen a (spaa), also called antigen b, antigen i/ii, or antigen p1, is an abundant cell envelope protein that is the major antigenic determinant of streptococcus sobrinus and other members of the streptococcus mutans group of cariogenic bacteria. this laboratory has previously reported the cloning and expression in escherichia coli of a bamhi restriction fragment of s. sobrinus dna containing most of the spaa gene (pya726) and encoding antigen i. regions of spaa encoding immuno ... | 1990 | 1694526 |
| cross-reactivity between the immunodominant determinant of the antigen i component of streptococcus sobrinus spaa protein and surface antigens from other members of the streptococcus mutans group. | most members of the streptococcus mutans group of microorganisms specify a major cell surface-associated protein, spaa, that is defined by its antigenic properties. the region of the spaa gene from streptococcus sobrinus 6715 encoding the immunodominant determinant of the major antigenic component (antigen i) of the spaa protein has recently been characterized. this study examined whether recognition of the immunodominant determinant is independent of the immunized animal host and whether antibo ... | 1990 | 1694822 |
| peptide sequences for sucrose splitting and glucan binding within streptococcus sobrinus glucosyltransferase (water-insoluble glucan synthetase). | the gene encoding glucosyltransferase responsible for water-insoluble glucan synthesis (gtf-i) of streptococcus sobrinus (formerly streptococcus mutans 6715) was cloned, expressed, and sequenced. a gene bank from s. sobrinus 6715 dna was constructed in vector puc18 and screened with anti-gtf-i antibody to detect clones producing gtf-i peptide. five immunopositive clones were isolated, all of which produced peptides that bound alpha-1,6 glucan. gtf-i activity was found in only two large peptides: ... | 1991 | 1704006 |
| immunological relationships between glucosyltransferases synthesizing insoluble glucan from streptococcus cricetus, streptococcus sobrinus and streptococcus downei. | the mr values and isoelectric points of glucosyltransferases synthesizing insoluble glucan (gtf-is) were determined, and the immunological relationships between them studied. the gtf-i enzymes were from streptococcus cricetus (mutans group serotype a), streptococcus sobrinus (mutans group serotypes d and g) and streptococcus downei (mutans group serotype h). by double immunodiffusion tests, the gtf-i enzymes from the three species possessed a common antigenic determinant; in addition, the gtf-i ... | 1991 | 1720167 |
| 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 |
| cariogenicity of milchschnitte (ferrero gmbh) and apple in program-fed rats. | the cariogenicity of ferrero milchschnitte and apple was tested in rats using a frequency-controlled feeding machine. twelve litters of osborne-mendel rats orally infected with streptococcus sobrinus omz-176 and actinomyces viscosus ny-1 were used. four treatment groups were tested: (1) cooked starch/sucrose 1:1 as positive control; (2) ferrero milchschnitte; (3) apple; (4) gastric intubation only as negative control. groups 1-3 were additionally fed by gastric intubation with essential nutrient ... | 1991 | 1747885 |
| interactions between and within streptococcus mutans and streptococcus sobrinus isolated from humans harboring both species. | the prevalence of streptococcus mutans and streptococcus sobrinus was examined in plaque samples from small discrete areas of the buccal tooth surfaces of seven subjects. strains of s. mutans and s. sobrinus were isolated and tested for bacteriocin-mediated interactions between and within the two species, using the stab inoculation technique. s. mutans and s. sobrinus did not colonize each tooth surface uniformly and, in plaque from small discrete sites, s. mutans and s. sobrinus were either und ... | 1991 | 1763286 |
| in vitro antibacterial effect of chlorhexidine added to glass-ionomer cements. | the aims of the present study were to investigate the antibacterial properties of glass-ionomer cements containing different concentrations of chlorhexidine and the possible release of chlorhexidine from the compound. chlorhexidine gluconate or diacetate was mixed with glass-ionomer cements and tested in vitro against strains of lactobacillus casei and mutans streptococci. a spectrophotometric test was used to monitor the release of chlorhexidine from the mixture. in a broth culture test, the hi ... | 1991 | 1763290 |
| salivary levels of mutans streptococci and lactobacilli in dentate 80- and 85-year-old swedish men and women. | the number of streptococcus mutans, streptococcus sobrinus, and lactobacilli in whole stimulated saliva was examined in 130 dentate 80- and 85-yr-old persons. 88.5% were positive for mutans streptococci and 29% carried greater than 10(6) cfu per ml saliva. s. mutans was most frequently isolated and was found in 114 persons (88%) alone or in combination with s. sobrinus. s. sobrinus was detected in 33 persons (25%), who also showed significantly higher salivary numbers of both mutans streptococci ... | 1991 | 1764902 |
| combined effects of zn(2+)-chlorhexidine and zn(2+)-cetylpyridinium chloride on caries incidence in partially desalivated rats. | the effects of zn2+ combined with either chlorhexidine or cetylpyridinium chloride (cpc) on caries incidence in partially desalivated rats were investigated. seven groups of 12 animals each received topical applications for 20 s with a saturated swab (0.2 ml) of the following aqueous solutions twice daily on weekdays (10 a.m. and 3 p.m.) and once daily during weekends (12 a.m.) for 5 wk: deionized water (placebo); 40 mm zinc acetate; 2.2 mm chlorhexidine diacetate; 4.4 mm cpc; 40 mm zinc acetate ... | 1991 | 1771376 |
| in vitro demineralization of enamel by f-sensitive and f-resistant mutans streptococci in the presence of 0, 0.05, or 0.5 mmol/l naf. | lactate production and accompanying enamel demineralization by fluoride-sensitive and fluoride-resistant mutans streptococci were studied in an in vitro demineralization model in the presence of 0, 0.05, or 0.5 mmol/l naf. the fluoride-resistant strains were derived from laboratory strains or were recently isolated strains from xerostomic patients on high-dose fluoride therapy. the demineralization model was composed of a cell suspension in a glucose-agarose gel overlying a bovine enamel block. ... | 1991 | 1774379 |
| in vitro acidogenic potential and mutans streptococci of human smooth-surface plaque associated with initial caries lesions and sound enamel. | samples of human dental plaque were pooled from several "white spot" smooth tooth surface areas as well as from several clinically-sound tooth surface areas in each of 12 caries-positive college students. each of the two samples from each subject was used for the determination of: (1) ph-lowering potential in vitro involving dispersed plaque suspensions, excess glucose supply, and a 60-minute test, and (2) the proportions of mutans streptococci and lactobacilli. when all subjects were considered ... | 1991 | 1774380 |
| mutans streptococci and non-mutans streptococci acidogenic at low ph, and in vitro acidogenic potential of dental plaque in two different areas of the human dentition. | samples of human dental plaque were obtained from sound tooth surfaces in the lower anterior and upper posterior areas of each of 11 subjects with various degrees of caries experience. both types of plaque were compared for: (1) their ph-lowering potential [ph at 10 and 60 min after sugar addition and the ph drop between 0 and 10 min (delta ph)] with an in vitro method involving dispersed plaque suspensions and excess glucose supply; (2) the proportions of mutans streptococci; and (3) the distri ... | 1991 | 1774381 |
| transmission of mutans streptococci. | it has been shown that early establishment of mutans streptococci in the mouth of infants increases risk of caries. extensive studies on the timing of infection, and on sources and routes of transmission of the organism have been performed. results of many studies suggest that the source of mutans streptococci is the mother, especially her saliva. methods used to attempt to verify this hypothesis have developed considerably in recent years. recent research and work in progress using methods base ... | 1991 | 1775473 |
| antibody responses to mutans streptococci in children. | because mutans streptococci (streptococcus mutans, s. sobrinus) are considered the main causative bacteria in human dental caries, immune responses to these bacteria have aroused much research interest over the last two decades. studies in man have focused mainly on salivary and serum antibodies developing naturally in response to oral colonization by mutans streptococci, or in relation to the development of dental caries. although both salivary (iga) and serum-derived (igg) antibodies have been ... | 1991 | 1775474 |
| [caries-inducing activity of soybean-oligosaccharide (sor) in vitro and in experimental dental caries of rats]. | the caries-inducing activity of soybean-oligosaccharide (sor: stachyose- and raffinose-rich sugar mixture) was examined in in vitro and in vivo experiments. streptococcus mutans mt 8148r fermented sor and produced acids. however streptococcus sobrinus 6715 did not ferment. sor was not able to act as a substrate for crude glucosyltransferases (gtase) of these mutans streptococci to synthesize the water-insoluble glucan. however, sor did not inhibit the synthesis of water-insoluble glucan from suc ... | 1991 | 1784869 |
| purification and characterization of recombinant cell surface protein antigen a of streptococcus sobrinus b13n. | 1. it has been reported that immunization of rhesus monkeys with the surface protein antigen i/ii from streptococcus mutans significantly reduced dental caries. 2. the surface protein antigen a (spaa) from streptococcus sobrinus is known to correspond antigenically to i/ii. md51 is an escherichia coli host containing pmd51, a plasmid encoding the spaa gene from streptococcus sobrinus b13n. 3. the recombinant spaa (rspaa) was purified from cell extracts of escherichia coli clone md51. 4. the puri ... | 1991 | 1786849 |
| comparison of the physicochemical surface properties of streptococcus rattus with those of other mutans streptococcal species. | mutans streptococci comprise a group of seven closely related, yet distinct species. the distinction between the four species used in this study, namely streptococcus sobrinus, streptococcus cricetus, streptococcus rattus, and streptococcus mutans, has been made only recently on the basis of dna homologies. in order to determine if there is a difference in the physicochemical surface properties of these species, strains were characterized by contact angles, zeta potentials and isoelectric points ... | 1991 | 1810653 |
| dental caries and mutans streptococci in the proximal areas of molars affected by the habitual use of xylitol chewing gum. | the relationship between the caries status and the microbiological status [mutans streptococci (ms)] in the proximal areas of lower right and upper left molars was investigated in subjects of the ylivieska xylitol study in finland (1982-1985) in a cross-sectional follow-up in 1988. those children who had used xylitol chewing gum regularly since 1982 showed significantly lower caries indices in 1988, including the proximal caries scores. the presence of ms (expressed in log10 colony-forming units ... | 1991 | 1810656 |
| effect of dentifrices containing either xylitol and glycerol or sorbitol on mutans streptococci in saliva. | in 76 adults, randomly distributed between two groups, a comparison was made of the effect on the level of mutans streptococci in saliva between two dentifrices containing: (1) xylitol (9.9%) and glycerol (20%) or (2) sorbitol (28%) as humectants. after the use of the dentifrices twice daily for 3 months, the levels of mutans streptococci had not changed significantly in the sorbitol-treated group, whereas a significant reduction (p less than 0.0005) was found in subjects using the xylitol/glyce ... | 1991 | 1810657 |
| fluoride and mutans streptococci in plaque grown on glass ionomer and composite. | the aim of this study was to compare the levels of fluoride and mutans streptococci in plaque grown on glass ionomer (ketac-fil) and composite (silar) restorations in vivo. from tunnels left under the brackets bonded either with glass ionomer or composite, 14-day-old plaque samples were collected 14, 28, and 42 days after bonding. for glass ionomer the mean counts of mutans streptococci in plaque were 0.5 x 10(3), 6.7 x 10(3), and 8.8 x 10(3) cfu at the first, second, and third collection, respe ... | 1991 | 1810658 |
| chain formation and de-chaining in streptococcus sobrinus sl-1. | regulation of chain length by chain-forming bacteria is believed to depend on wall-associated autolytic activity and environmental conditions. in this study, the chain length of streptococcus sobrinus sl-1 was determined under various initial culture and ph conditions and naf concentrations. crude wall extracts were prepared by dilute alkali treatment of whole cells and were tested for de-chaining activity. the results indicate that s. sobrinus sl-1 grows primarily as short chains under alkaline ... | 1991 | 1820572 |
| isolation and sequence of an active-site peptide containing a catalytic aspartic acid from two streptococcus sobrinus alpha-glucosyltransferases. | an active-site peptide containing an aspartic acid implicated in catalysis has been isolated and sequenced from two streptococcus sobrinus extracellular glucosyltransferases: sucrose:1,3-alpha-d-glucan 3-alpha-d-glucosyltransferase (gtase-i) and sucrose:1,6-alpha-d-glucan 6-alpha-d-glucosyltransferase (gtase-s). the sequenced peptides, tagged with radiolabeled glucose, were isolated from a pepsin digest of a stabilized glucosylenzyme complex prepared by rapidly denaturing a reaction of enzyme an ... | 1991 | 1827439 |
| differences in cariogenicity between fresh isolates of streptococcus sobrinus and streptococcus mutans. | streptococcus sobrinus is known to possess cariogenic properties in vitro. it can produce acid in large amounts and it has the capacity to adhere to enamel and other surfaces. however, most studies on cariogenicity have been performed with laboratory strains that have been subcultured over long periods of time. therefore, the cariogenicity and acidogenicity of 9 fresh isolates of both s. sobrinus and streptococcus mutans from human dental plaque were compared. the bacteria were inoculated into t ... | 1991 | 1829395 |
| substrate specificity of hydrolase activity of the primer-dependent glucosyltransferases from streptococcus sobrinus. | four kinds of glucosyltransferases, p1, p2, p3 and p4, were separately purified from the culture supernatant of streptococcus sobrinus. their dependencies on primer were analysed. there were two primer-dependent glucosyltransferases (p3 and p4). in the absence of primer 1,6-alpha-d-glucan, p3 was not able to produce glucan from sucrose. however, p3 showed sucrose hydrolase activity, whereas p4 was still able to produce glucan without primer 1,6-alpha-d-glucan. consequently, glucosyltransferase a ... | 1991 | 1830918 |
| cloning of a streptococcus sobrinus gtf gene that encodes a glucosyltransferase which produces a high-molecular-weight water-soluble glucan. | the gtf gene coding for glucosyltransferase (gtf), which produces a water-soluble glucan, was cloned from streptococcus sobrinus omz176 (serotype d) into plasmid vector pbr322. this gene was expressed in escherichia coli, and the product was purified to near homogeneity. the antigenicity of recombinant gtf (rgtf) was examined with the antisera raised against purified gtf p1, p2, p3, and p4 obtained from s. sobrinus aht (serotype g). the rgtf reacted only with anti-gtf p1 serum in a western blot ... | 1991 | 1832662 |
| effects of propolis on dental caries in rats. | propolis, the resinous hive product collected by bees, is important in the defense of the hive. the effects of propolis on growth and glucosyltransferase activity of streptococcus sobrinus 6715, streptococcus mutans ps14 and streptococcus cricetus omz61 in vitro, and on dental caries in rats infected with s. sobrinus 6715 were investigated. propolis had antimicrobial activity against s. sobrinus, s. mutans and s. cricetus, and inhibited both water-insoluble glucan synthesis and glucosyltransfera ... | 1991 | 1836157 |
| the extension of alpha-d-1,3-branch linkages by 1,3-alpha-d-glucan synthase from streptococcus sobrinus. | in the presence of an acceptor, 1,3-alpha-d-glucan synthase of streptococcus sobrinus synthesizes water-insoluble glucans from sucrose. under such conditions, 1,3-alpha-d-glucoside linkages were extended without any change in the glucose-residue number between the 1,3,6-branch points on the acceptor. from these results, the mechanisms of water-insoluble-glucan formation were proposed as follows: (i) the attachment of an acceptor to the glucan binding sites of 1,3-alpha-d-glucan synthase occurs d ... | 1991 | 1838088 |
| partial characterization of the glucosyltransferases of an oral streptococcus salivarius strain. | the oral streptococcus salivarius strain s3 possessed extracellular glucosyltransferase (gtf) and cell-associated fructosyltransferase activities. chromatofocusing column chromatography of crude gtf yielded multiple peak fractions, which were categorized into two types which catalysed (1) water-insoluble glucan synthesis and (2) water-soluble glucan formation. the gtf isozyme eluted in fraction 29 synthesized mutanase- and dextranase-sensitive insoluble glucan from sucrose, while fraction 81 gtf ... | 1991 | 1839049 |
| complete nucleotide sequence of the gene for a surface protein antigen of streptococcus sobrinus. | the complete nucleotide sequence of the gene for a cell surface protein antigen (spaa) of streptococcus sobrinus mt3791 (serotype g) was determined. the spaa gene consisted of 4,698 bp and coded for a protein of 170,202 da. a putative signal peptide was found in the amino-terminal end of the protein. a potential promoter sequence and a putative shine-dalgarno sequence preceded the open reading frame. two internal repeating amino acid sequences were present in spaa. one repeating region, located ... | 1991 | 1840575 |
| influence of rampant caries in dams on caries activity in their offspring. | available evidence indicates that infants, for the most part, acquire their oral flora, in particular streptococcus mutans, from their mothers. the purpose of this study was to explore the effect of rampant caries in rat dams on subsequent caries activity in their offspring. rampant caries was induced by surgical desalivation of four dams, and subsequent infection with streptococcus sobrinus 6715. two intact dams served as controls. desalivated dams, having rampant caries, reared litters that ex ... | 1991 | 1843993 |
| sequence and structural analysis of surface protein antigen i/ii (spaa) of streptococcus sobrinus. | streptococcal antigen i/ii or the surface protein antigen a (spaa) of streptococcus sobrinus is an adhesin which mediates binding of the organism to tooth surfaces. the complete sequence of the gene which encodes spaa has been determined. the gene consists of 4,584 bp and encodes a protein of 1,528 amino acid residues. the deduced amino acid sequence shows extensive homology with those of the cell surface adhesins from streptococcus mutans serotypes c and f and from streptococcus sanguis. struct ... | 1991 | 1855987 |
| interactions of sanguinarine and zinc on oral streptococci and actinomyces species. | sanguinaria extract, which contains benzophenanthridine alkaloids, has been used as a folk medicine for many years. minimum inhibitory and minimum bactericidal concentrations (mic and mbc values) for sanguinarine were determined for common and etiologically important plaque bacteria. because the efficacy of sanguinarine is believed to be enhanced by zinc, isobolograms were assessed to determine their mode(s) of interaction. hydrogen ion concentration influenced the inhibitory activity of both sa ... | 1991 | 1878916 |
| inhibition of the growth of streptococcus mutans, streptococcus sobrinus and lactobacillus casei by oral peroxidase systems in human saliva. | streptococcus mutans, strep. sobrinus and lactobacillus casei were grown in glucose-supplemented, sterilized, human whole saliva, adjusted to ph 5, 6 or 7. components of the antibacterial peroxidase system--hypothiocyanous acid (hoscn) and hypothiocyanite ions (oscn-)--were generated by adding exogenous h2o2 to sterilized saliva containing endogenous peroxidases and thiocyanate (scn-) ions. hoscn/oscn- generation was proportional to the amount of h2o2 added, and more hoscn/oscn- was detected in ... | 1991 | 1905532 |
| effects of an acidic calcium phosphate solution and the intraoral fluoride-releasing device on dental caries and fluoride uptake in rats. | this investigation comprised two studies evaluating the effects of an acidic calcium phosphate solution (cps) on fluoride uptake in the enamel, glycolysis of dental plaque, the incidence of dental caries and urinary fluoride concentrations of rats wearing an intraoral fluoride-releasing device (ifrd). in the first study, cps-fluoride treatment preceded the cariogenic challenge. in the second study, the cariogenic challenge preceded the treatments. in the first study, cps treatments increased the ... | 1991 | 1913764 |
| trehalulose does not induce dental caries in rats infected with mutans streptococci. | the effects of trehalulose, a structural isomer of sucrose, and a syrup (tp syrup) rich in trehalulose and palatinose on caries development were examined in specific pathogen-free sprague-dawley rats. streptococcus mutans mt8148r and streptococcus sobrinus 6715 fermented the syrup which resulted in acid production, while both strains were found not to utilize trehalulose. furthermore, trehalulose did not serve as a substrate for glucosyltransferases of these mutans streptococci to synthesize wat ... | 1991 | 1913765 |
| influence of milk, lactose-reduced milk, and lactose on caries in desalivated rats. | there is a growing population who suffer from hyposalivation. these patients frequently sip liquids to alleviate their discomfort. milk appears to have many of the physical properties of a good saliva substitute. desalivated rats given 2% milk or lactose-reduced milk remained essentially caries-free. in contrast, animals given sucrose or lactose to drink developed caries. in addition, animals given sucrose or lactose harbored significantly higher populations of streptococcus sobrinus than did ot ... | 1991 | 1913766 |
| effect of calcium ions on cell surface electrostatics of bacteroides gingivalis and other oral bacteria. | surface electrostatics of bacteroides gingivalis and other oral bacteria were examined. a polarization circuit was employed using platinum electrodes exposed in each bacterial suspension and the number of bacteria adsorbed to the anode and cathode were then estimated. in all bacteria (b. gingivalis, streptococcus sobrinus, s. mutans, s. salivarius, s. sanguis and actinomyces viscosus), the number of cells adsorbed to the anode were much greater than the number of cells adsorbed to the cathode. t ... | 1991 | 1930564 |
| chronic peroral administration of streptococcus sobrinus to conventional laboratory rats produces cycling levels of salivary antibodies. | conventional outbred rats were fed streptococcus sobrinus for 24 weeks and elisa was used to identify isotypes of antibodies against bacteria in saliva and serum. quantities of antibodies from experimental rats were compared with values derived from the control population. saliva igm and iga anti-s. sobrinus from experimental rats were greater than controls at week 3, were much less at week 9, but normal levels were found by week 13. igg antibodies in saliva peaked at weeks 5 and 9 but fell to c ... | 1991 | 1945480 |
| antimicrobial susceptibility of 1042 strains of streptococcus mutans and streptococcus sobrinus: comparison from 1985 to 1989. | a total of 1042 strains of streptococcus mutans and streptococcus sobrinus isolated between 1985 and 1989 were tested to study the evolution of their sensitivity to penicillin, amoxycillin, amoxycillin/clavulanic acid, cefuroxime, tetracycline, erythromycin, spiramycin, acetyl spiramycin, lincomycin and clindamycin. the strains were taken from stock cultures and isolated from human saliva and dental plaque. the minimal inhibitory concentration (mic) was determined by an agar dilution method. exc ... | 1991 | 1945497 |
| the prevention of dental caries by blis-mediated inhibition of mutans streptococci. | many of the strategies that have been formulated to decrease the incidence of dental caries have focused upon attempting to reduce either the numbers or the acidogenic activities in dental plaque of the mutans streptococci. in recent years there has been a growing interest in a new method of caries control which depends upon exploiting the ability of certain bacteria to produce antibiotics called bacteriocin-like inhibitory substances (blis) with killing activity for mutans streptococci. the app ... | 1991 | 1956623 |
| immunogenicity and protective effect against oral colonization by streptococcus mutans of synthetic peptides of a streptococcal surface protein antigen. | streptococcus mutans is known to be a major causative organism of human dental caries. a surface protein ag with a molecular mass of 190 kda of s. mutans (pac) is receiving attention as an anticaries vaccine. we have recently determined the complete nucleotide sequence of the gene for pac. in this study, four peptides were synthesized on the basis of amino acid sequence of pac. among these peptides, pac(301-319) corresponding to the alanine-rich repeating amino acid region was the most strongly ... | 1991 | 1984447 |
| enhancing the virulence of streptococcus sobrinus in rats. | the purpose of this study was to explore the virulence of strains of streptococcus sobrinus that had been re-isolated from a desalivated rat. furthermore, we wished to determine the influence of desalivation on the acidogenicity of fasting and sucrose-pulsed dental plaque in rats infected by strains of s. sorbrinus. experimental groups were formed and infected as follows: group 1, desalivated animals, s. sorbrinus atcc27352; group 2, intact animals, infected as in group 1; group 3, desalivated a ... | 1991 | 1991859 |
| microbiological and immunological aspects of experimental periodontal disease in rats: a review article. | animal models in which microbiological and immunological aspects of periodontal disease can be studied prospectively seem well warranted. the rat bears much resemblance to man with respect to periodontal anatomy, development and composition of dental plaque, histopathology of periodontal lesions, and basic immunobiology. furthermore, reproducible methods are available for assessment of periodontal disease in rats, and detectable periodontal destruction can be induced in a few weeks in these anim ... | 1991 | 2002433 |
| 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 |
| effect of variation in growth conditions on the activity of dextranase inhibitor in continuous cultures of streptococcus sobrinus. | the activity of free extracellular dextranase inhibitor was determined in strains of streptococcus sobrinus which were grown in a chemostat under a variety of defined conditions. maximum release of dextranase inhibitor occurred at low growth rate in glucose-limited medium at ph 6.5. free inhibitor could not be detected when the strains were grown at high growth rate or in batch culture. | 1991 | 2023543 |
| dental caries and mutans streptococci in selected groups of urban and native indian schoolchildren in mexico. | two groups of mexican children aged 12-14 yr were examined for dental caries and salivary mutans streptococci counts. one hundred lived in mexico city and 100 belonged to a native mazahua indian population. the prevalence of caries, diagnosed according to who, was 90% in mexico city and 82% in the indian community. mean dmft was 5.98 and 3.57 respectively. saliva samples were analyzed for mutans streptococci by the "strip mutans" method. further identification of the biotype/serotype was done. m ... | 1991 | 2049931 |
| dental location of streptococcus mutans and streptococcus sobrinus in humans harboring both species. | the distribution and prevalence of streptococcus mutans and streptococcus sobrinus were determined in plaque samples from the cervical areas of all buccal, lingual and approximal tooth surfaces and from the fissures of all occlusal sites in 40 subjects harboring both species. s. mutans was detected more often and in higher numbers than s. sobrinus. there were more teeth detected with s. mutans only than with s. sobrinus only. most teeth harbored both of these mutans streptococci species, indicat ... | 1991 | 2059977 |
| construction of noti restriction map of the streptococcus mutans genome. | streptococcus mutans and streptococcus sobrinus are the major causative organisms of human dental caries. pulsed-field gel electrophoresis (pfg) showed that the restriction enzyme noti produced ten and six dna fragments from the genomes of s. mutans strain mt8148 and s. sobrinus strain 6715, respectively. the sizes of the chromosomes of s. mutans and s. sobrinus were each estimated to be about 2200 kb. the noti restriction map of s. mutans mt8148 genome was constructed by southern blot analysis ... | 1990 | 2079621 |
| binding of streptococci of the "mutans" group to type 1 collagen associated with apatitic surfaces. | the present study surveyed the ability of 21 strains of cariogenic streptococci of the "mutans" group to bind to human type 1 collagen adsorbed on hydroxyapatite (ha) surfaces. all strains of streptococcus cricetus (serotype a) and streptococcus rattus (serotype b) tested attached strongly to collagen-treated ha (c-ha). streptococcus mutans strains of serotype c and streptococcus sobrinus strains of serotype d or g attached poorly; or not at all, to c-ha. s. mutans strains omz-175 (serotype f) a ... | 1990 | 2080067 |
| human strains of mutans streptococci show different cariogenic potential in the hamster model. | the cariogenic potential of fresh humans strains of streptococcus mutans and streptococcus sobrinus was examined in hamsters maintained on a high sucrose diet. the strains 1b 16 (s. mutans) and b13 (s. sobrinus) isolated 20-25 yrs ago served as positive controls. three series of experiments were run. some strains were tested once and some strains were tested in all 3 experiments. the animals infected with s. sobrinus strains generally showed lower caries scores than those infected with s. mutans ... | 1990 | 2082240 |
| cloning of the amino terminal nucleotides of the antigen i/ii of streptococcus sobrinus and the immune responses to the corresponding synthetic peptides. | a portion of the antigen i/ii (spaa, b, p1) gene of streptococcus sobrinus 6715, containing the coding sequence for the amino terminal 684 amino acids of the protein, was cloned in bacteriophage lambda gt10. selection was by immunological detection using a polyclonal antiserum to the antigen i/ii from strep. mutans. from the amino acid sequence, peptides were synthesized, 15 amino acids in length, that covered the entire sequence. in total, 260 synthetic peptides were synthesized and evaluated f ... | 1990 | 2088235 |
| maintenance of proton motive force by streptococcus mutans and streptococcus sobrinus during growth in continuous culture. | the components of the transmembrane electrochemical proton gradient, or proton motive force (pmf, delta p), were determined in cells of streptococcus mutans ingbritt and streptococcus sobrinus atcc 27352 growing in continuous culture under conditions of changing glucose concentration, growth rate and growth ph. the ph gradient (delta ph) and membrane electrical potential (delta psi) were assayed with the weak acid, salicyclic acid, and the lipophilic cation, methyltriphenylphosphonium iodide, re ... | 1990 | 2098703 |
| a iiiman protein is involved in the transport of glucose, mannose and fructose by oral streptococci. | we show in this article that the transport of glucose, mannose and fructose by the phosphoenolpyruvate: mannose phosphotransferase system of oral streptococci requires the participation of a protein component that we have called iiiman. this protein was purified from streptococcus salivarius by chromatography on deae-cellulose, deae-tsk, hydroxyapatite, and dyematrex green a. the purified protein migrated as a 38,900 molecular weight protein on a sodium dodecyl sulfate polyacrylamide gel. howeve ... | 1990 | 2098704 |
| dental caries in congenitally athymic rats. | the importance of the immune response in dental infection was evaluated in heterozygous (rnu/+) normal and homozygous (rnu/rnu) congenitally athymic "nude" rowett rats. animals of both types were infected, or immunized and infected, with mutans streptococci (streptococcus sobrinus strain 6715). the mean numbers of s. sobrinus cells recovered from the nude rats were higher than those from comparable (immune/nonimmune) normal rats in 10 of 12 possible comparisons. also, s. sobrinus constituted a g ... | 1990 | 2098708 |
| influence of sweetening agents in solution on dental caries in desalivated rats. | sucralose (trichlorogalactosucrose), sorbitol and aspartame in drinking water induced little or no caries in desalivated rats infected with streptococcus sobrinus and actinomyces viscosus and receiving their essential nutrition by gastric gavage. in contrast, sucrose and fructose induced extensive decay. only sucrose could sustain implantation of strep. sobrinus in these animals. the populations of a. viscosus were sparse (0.3-0.5%) in the animals given fructose and sucrose. large populations of ... | 1990 | 2124801 |
| [inhibitory effects of a hot water extract from japanese tea on the cell growth of mutans streptococci]. | this study was undertaken to examine the effect of a hot water extract from japanese tea on the cellular growth of mutans streptococci in vitro. the extract contained polyphenol compounds, mainly catechin derivatives. few fluoride components were contained in the extract. streptococcus mutans mt8148r (serotype c) and s. sobrinus mt6715 (serotype g) strains were used in the present study. the organisms (10-10(7) cfu/ml) were cultured in brain heart infusion (bhi) and tryptose phosphate (tp) broth ... | 1990 | 2133962 |
| [detection of mutans streptococci by latex agglutination test and its application as a caries-activity test]. | the number of mutans streptococci in saliva and dental plaque has been reported to correlate with the incidence of dental caries. this report describes a simple and rapid diagnostic method for the detection of mutans streptococci in dental plaque using latex agglutination (la) test. latex particles (0.876 microns, diameter) were sensitized with partially purified antibodies against whole cells of streptococcus mutans mt8148 (c), mt703r (e) and omz175 (f) and streptococcus sobrinus b13 (d) and 67 ... | 1990 | 2135419 |
| characterization of glucan involved in the reduction of dental caries in rats. | culture supernatant fluids (sf) of mutant 108 obtained from streptococcus sobrinus 6715, when incubated with sucrose, produce large amounts of water-soluble glucans. mainly, two water-soluble glucan synthesizing glucosyltransferases (gtases) were found in culture sf by isoelectric focusing. these two gtases had higher activities than those from the parent strain. the gtase which synthesizes water-insoluble glucan totally lacked the mutant. when the glucan preparation synthesized by the sf was su ... | 1990 | 2137352 |
| size and subdomain architecture of the glucan-binding domain of sucrose:3-alpha-d-glucosyltransferase from streptococcus sobrinus. | mild trypsin proteolysis of streptococcus sobrinus sucrose:3-alpha-d-glucosyltransferase (gtf-i) reduced most of the enzyme to small products but left a few large fragments undigested. the digest had no glucosyl transfer activity, but several digestion products had an affinity for glucan equivalent to that of the native enzyme. the glucan-binding fragments ranged in size from 17 to 60 kilodaltons (kda), with a particularly prominent 42-kda fragment. the largest of these (60 kda) appears to be th ... | 1990 | 2142138 |
| analysis of the streptococcus downei gtfs gene, which specifies a glucosyltransferase that synthesizes soluble glucans. | the complete nucleotide sequence was determined for the streptococcus downei (previously streptococcus sobrinus) mfe28 gtfs gene which specifies a glucosyltransferase (gtf-s) producing water-soluble glucan. a single open reading frame which encodes a mature protein with a molecular weight of 147,408 (1,328 amino acids) and a putative signal peptide 36 or 37 amino acids in length was detected. gtf-s shares extensive sequence similarity with gtf-i (gtfi) from s. downei and gtf-i (gtfb) and gtf-si ... | 1990 | 2142479 |