Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
|---|
| a comparison of antimicrobial activity of etchants used for a total etch technique. | the purpose of this study was to determine the antimicrobial activity of eight commercially available etchant materials and positive and negative controls as they came into contact with bacteria commonly found within the oral cavity. the following bacteria were used in this study: streptococcus mutans, streptococcus salivarius, and actinobacillis actinomycetocomitants. the study was conducted in two parts: part i--etchants and controls placed within wells in agar plates; part ii--enamel-dentin d ... | 1997 | 9484166 |
| in vivo binding of the salivary glycoprotein ep-gp (identical to gcdfp-15) to oral and non-oral bacteria detection and identification of ep-gp binding species. | extra parotid glycoprotein (ep-gp) is a glycoprotein isolated from human saliva, having homologues in several other body fluids. the biological role of ep-gp and its homologues is unknown. recently, ep-gp was shown to bind in vitro to the bacterium streptococcus salivarius hb. in contrast, no binding to a number of other oral microorganisms could be demonstrated. in the present study we have determined whether binding of ep-gp to bacteria occurs in vivo in saliva and in other ep-gp containing bo ... | 1997 | 9088536 |
| rapid procedure for acid adaptation of oral lactic-acid bacteria and further characterization of the response. | acid-adaptive responses could be induced readily in oral lactic-acid bacteria by growing them in batch cultures with excess sugar or more conveniently and rapidly by transferring cells to acidified growth media for the time required for biomass doubling. the response of streptococcus mutans gs-5 was induced in a progressive rather than all-or-nothing way, and the extent of acid tolerance was inversely related to the ph of the inducing medium over a range from 8.5 to 5. the weak acids fluoride, a ... | 1997 | 9090104 |
| cell wall anchoring of the streptococcus pyogenes m6 protein in various lactic acid bacteria. | the m6 protein from streptococcus pyogenes is the best-characterized member of a family of cell envelope-associated proteins. based on the observation that the c-terminal sorting signals of these proteins can drive cell wall anchoring of heterologous unanchored proteins, we have cloned and expressed the emm6 structural gene for the m6 protein in various lactic acid bacteria (lab). the emm6 gene was successfully expressed from lactococcal promoters in several lactococcus lactis strains, an animal ... | 1997 | 9139932 |
| the phosphoenolpyruvate:sugar phosphotransferase system of oral streptococci and its role in the control of sugar metabolism. | oral streptococci are sugar-fermentative bacteria comprising at least 19 distinct species and are a significant proportion of the normal microbial population of the mouth and upper respiratory tract of humans. these streptococci transport several sugars by the phosphoenolpyruvate:sugar phosphotransferase system (pts) which concomitantly catalyzes the phosphorylation and translocation of mono- and disaccharides via a chain of enzymic reactions that transfer a phosphate group from phosphoenolpyruv ... | 1997 | 9050218 |
| nucleotide sequence analysis of the streptococcus gordonii glucosyltransferase gene, gtfg. | streptococcus gordonii has an extracellular glucosyltransferase (gtf) that polymerizes the glucose moiety of sucrose to form both water-soluble and water-insoluble glucans. whereas multiple gtf genes have been identified in strains of mutans streptococci and streptococcus salivarius, a single gene, designated gtfg, encodes the gtf of s. gordonii challis. gtfg is also unique among the characterized gtfs in that it has a described regulatory determinant, rgg. furthermore, the gtf activity in s. go ... | 1997 | 9063645 |
| [acute streptococcus salivarius meningitis after spinal anesthesia]. | the case of a 50-year-old woman who experienced an acute streptococcus salivarius meningitis after a spinal anaesthesia for hysteroscopy is reported. the contamination of the cerebrospinal fluid may occur from a puncture during a bacteriaemia. contamination from the patient's skin and from the upper airway's flora of the operator seems to be a more plausible cause. spinal anaesthesia is contra-indicated in the febrile patient. asepsis is essential during spinal puncture, including wearing a surg ... | 1997 | 9686094 |
| natural milk cultures for the production of argentinian cheeses. | samples (32) of natural milk cultures used in the santa fe, argentina, area for soft and semihard cheese production were examined. the microbial composition (including lactic acid microflora characterization) and technological parameters (acidifying and proteolytic activities) were evaluated. the cultures contained mainly thermophilic lactic acid bacteria, identified as streptococcus salivarius subsp. thermophilus (96.8% of the total strains) and enterococcus spp. the strains showed a low proteo ... | 1997 | 10465042 |
| streptococcus salivarius meningitis: a case report and literature review. | twelve hours after spinal anaesthesia, a 61-year-old patient developed meningitis with fever, somnolence, headache and stiffness of the neck. the cerebrospinal fluid was found to contain 5.279/mm(3) cells (95 granulocytes), 12.800 mg/l protein and 14.0 mmol/l lactate. streptococcus salivarius was detected in the culture. the patient was treated with antibiotics (initially cefotaxime, fosfomycin and gentamycin, later piperacillin and sulbactam). restitutio ad integrum took place after 7 days. thi ... | 1997 | 24283828 |
| antimicrobial susceptibility of viridans group streptococci in taiwan with an emphasis on the high rates of resistance to penicillin and macrolides in streptococcus oralis. | the in-vitro susceptibilities of 13 antimicrobial agents were determined for 207 isolates of viridans group streptococci recovered from patients with significant infections in taiwan during 1995 and 1997. variable degrees of susceptibility existed among nine species. high-level penicillin resistance (mic > or = 4.0 mg/l) was found most frequently in streptococcus oralis (35%), followed by streptococcus mitis (20%) and streptococcus salivarius (8%). however, s. salivarius showed the lowest rate o ... | 1998 | 9687100 |
| streptococcus salivarius urease expression: involvement of the phosphoenolpyruvate:sugar phosphotransferase system. | urease expression in streptococcus salivarius 57.1 is induced by acidic ph, and further enhanced at high growth rate and with excess carbohydrate. notably, the phosphoenolpyruvate (pep):sugar phosphotransferase system (pts) activity is repressed in oral streptococci under the same conditions. to test the hypothesis that the pts may be involved in urease regulation, spontaneous mutants (pts-1 and pts-4) that were resistant to 2-deoxyglucose were isolated. when compared to wild-type, pts-1 was dev ... | 1998 | 9711847 |
| random amplified polymorphic dna and amplified ribosomal dna spacer polymorphism: powerful methods to differentiate streptococcus thermophilus strains. | streptococci from different collections and dairy materials were characterized by conventional and molecular methods. after amplification of the 16s-23s rdna spacer region, all the strains referable to the genus streptococcus exhibited a single polymerase chain reaction (pcr) product, allowing their differentiation from enterococci. cleaving this pcr product with hae iii, two different restriction patterns could be observed, allowing streptococcus salivarius dsm 20560t, strep. thermophilus ncdo ... | 1998 | 9721653 |
| antibacterial temporary filling materials: the effect of adding various ratios of ag-zn-zeolite. | the effect of a new type of antibacterial temporary filling material was evaluated. ag-zn-zeolite (bactekiller, kanebo, japan) and sio2 filler were incorporated into urethane acrylate monomer paste in amounts of 5/55, 10/50, 20/40 and 30/30 wt%, respectively. the present study was designed to use a dye penetration test to measure direct inhibition of bacterial growth of four oral bacteria (streptococcus mutans, streptococcus mitis, streptococcus salivarius, streptococcus sanguis). the amounts of ... | 1998 | 9722093 |
| acid production from lactulose by dental plaque bacteria. | representative strains of oral streptococci, lactobacilli and bifidobacteria were incubated overnight with lactulose or other carbohydrates and the final ph recorded. most bacteria tested were able to metabolize lactulose with the exception of strains of streptococcus salivarius, lactobacillus acidophilus and lact. fermentum. streptococcus mutans produced most acid overnight but the initial rate of acid production from lactulose by uninduced cultures was very low. plaque ph was monitored in 12 v ... | 1998 | 9750322 |
| [2 cases of iatrogenic oral streptococcal infection: meningitis and spondylodiscitis]. | the multiplication of invasive spine investigations for either diagnostic or therapeutical purposes increases the risk for iatrogenic infections. we report two cases of iatrogenic infections, one case of meningitidis and one case of spondylodiscitis due to streptococcus viridans. | 1998 | 9775073 |
| 'soft-particle' analysis of the electrophoretic mobility of a fibrillated and non-fibrillated oral streptococcal strain: streptococcus salivarius. | the electrophoretic mobility of microbial cell surfaces can be analysed in terms of a so-called soft layer model, in which the electrophoretic mobility is described as originating from the potentials over the surface charge layer and the membrane fixed charges. often, the polyelectrolyte layer deforms under the influence of ionic strength variations. in the soft layer analysis of electrophoretic mobilities this is expressed in the softness 1/lambda. here, we determined the softness of two oral s ... | 1998 | 9779584 |
| transcriptional regulation of the streptococcus salivarius 57.i urease operon. | the streptococcus salivarius 57.i ure cluster was organized as an operon, beginning with urei, followed by ureabc (structural genes) and ureefgd (accessory genes). northern analyses revealed transcripts encompassing structural genes and transcripts containing the entire operon. a sigma70-like promoter could be mapped 5' to urei (purei) by primer extension analysis. the intensity of the signal increased when cells were grown at an acidic ph and was further enhanced by excess carbohydrate. to dete ... | 1998 | 9791132 |
| acid-regulated proteins induced by streptococcus mutans and other oral bacteria during acid shock. | our previous research has demonstrated that with the more aciduric oral bacteria, an acid shock to sub-lethal ph values results in the induction of an acid tolerance response that protects the cells at extremely low ph (ph 3.0-4.0) that kills unadapted control cells maintained at ph 7.5 (oral microbiol immunol 1997: 12: 266-273). in this study, we were interested in comparing the protein profiles of acid-shocked and control cells of nine organisms from three acid-ogenic genera that could be cate ... | 1998 | 9807121 |
| role of c-terminal domains in surface attachment of the fructosyltransferase of streptococcus salivarius atcc 25975. | the cell-associated beta-d-fructosyltransferase of streptococcus salivarius, which is devoid of the cell wall anchoring motif, lpxtg, is released on exposure to its substrate, sucrose. deletions within the c terminus of the enzyme implicated both the hydrophobic and the proline-glycine-serine-threonine-rich wall-associated domain in stabilizing the enzyme on the cell surface. | 1998 | 9829954 |
| [alpha-hemolytic streptococci and root canal irrigants. an evaluation of the bactericidal efficacy of sodium hypochlorite and chlorhexidine gluconate plus cetrimide]. | the main bacterial species present in pulpal and periapical microbic flora is alpha-hemolytic streptococci. they are regarded as facultative anaerobes which prefer to grow in anaerobiosis. canal irrigation plays an important role in the success of endodontic treatment given that, on the one hand, it encourages the gradual elimination of the smear layer, and on the other it neutralises microbic flora in the root canal. the aim of this study was to test the microbiological efficacy of sodium hypoc ... | 1998 | 9835743 |
| streptococcus salivarius meningitis after spinal anesthesia. | 1998 | 9856738 | |
| purification and properties of a bacteriocin of staphylococcus epidermidis isolated from dental plaque. | an extracellular bacteriocin of staphylococcus epidermidis isolated from dental plaque was purified and characterized. its molecular mass was 3500 da and pi was 10.5. this bacteriocin inhibited the growth of staphylococcus aureus, streptococcus salivarius, and streptococcus mitis, but streptococcus mutans, streptococcus sanguis and other oral indigenous bacterial species examined were not inhibited. the mode of inhibition was found to be bacteriostatic. | 1998 | 9872117 |
| antibacterial activity of camellia sinensis extracts against dental caries. | different bacteria were separated from saliva and teeth of cariogenic patients and identified by a variety of morphological and biochemical tests. extracts of green tea strongly inhibited escherichia coli, streptococcus salivarius and streptococcus mutans. the antibacterial effect of green and black tea extracts were compared with those of amoxicillin, cephradine and eugenol. | 1998 | 9875456 |
| the phosphoenolpyruvate:mannose phosphotransferase system of streptococcus salivarius. functional and biochemical characterization of iiabl(man) and iiabh(man). | previous studies have suggested that the phosphoenolpyruvate:mannose phosphotransferase system of streptococcus salivarius consists of a nonphosphorylated enzyme ii domain that functions in tandem with a separate enzymatic complex called iii(man). the iii(man) complex is believed to be composed of two protein dimers with molecular masses of approximately 72 kda. analysis of these proteins by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate has indicated that one dimer ... | 1998 | 9484231 |
| mutacin production by streptococcus mutans may promote transmission of bacteria from mother to child. | the production of bacteriocin-like inhibitory substances, mutacins, by mutans streptococci varies among isolates. to find if the degree of mutacin activity of an isolate was related to its transmission between mother and her child, 19 mothers and their 18-month- to 3-year-old children were sampled for their oral mutans streptococci. in addition, the stability of mutacin activity was studied with isolates from the mothers and with isolates from five unrelated 5-year-old children in 5- to 7-year f ... | 1998 | 9596721 |
| bacterial meningitis following combined spinal-epidural analgesia for labour. | we report a case of streptococcus salivarius meningitis following combined spinal-epidural analgesia for labour. although rare, bacterial meningitis following combined spinal-epidural anaesthesia is being increasingly described. we review the previously reported cases and discuss the possible aetiological causes and the aseptic precautions likely to reduce the incidence of infectious complications. | 1998 | 9613275 |
| effect of low-molecular-weight chitosans on the adhesive properties of oral streptococci. | it was previously shown that a low-molecular-weight chitosan and its derivatives n-carboxymethyl chitosan and imidazolyl chitosan inhibit streptococcus mutans adsorption to hydroxyapatite. the ability of the same molecules to interfere with adhesive properties of other oral streptococci (streptococcus sanguis, streptococcus gordonii, streptococcus constellatus, streptococcus anginosus, streptococcus intermedius, streptococcus oralis, streptococcus salivarius, streptococcus vestibularis) was test ... | 1998 | 10093536 |
| molecular relationships and antimicrobial susceptibilities of viridans group streptococci isolated from blood of neutropenic cancer patients. | from january 1995 to may 1998, 57 episodes of bacteremia due to viridans group streptococci were identified in 50 febrile neutropenic patients with hematologic malignancies. four patients experienced two separate episodes of streptococcal bacteremia, and one patient had four separate episodes of streptococcal bacteremia. strains were identified to species level as streptococcus mitis (n = 37), streptococcus oralis (n = 19), and streptococcus salivarius (n = 1). epidemiologic relatedness of these ... | 1999 | 10325340 |
| antimicrobial effects of various endodontic irrigants on selected microorganisms. | this study was undertaken to determine the antimicrobial effect of various endodontic irrigants against six selected microorganisms. | 1999 | 10371903 |
| study of the possible mechanisms involved in the mucosal immune system activation by lactic acid bacteria. | the induction of a mucosal immune response is not easy due to the development of oral tolerance, but under some conditions, bacteria can activate this immune system. antigens administered orally can interact with m cells of peyer's patches or bind to the epithelial cells. we have demonstrated that certain lactic acid bacteria are able to induce specific secretory immunity, and others will enhance the gut inflammatory immune response. the aim of this work was to establish the reason for these dif ... | 1999 | 10386296 |
| purification and enzymic properties of the fructosyltransferase of streptococcus salivarius atcc 25975. | the recombinant fructosyltransferase (ftf) of streptococcus salivarius was expressed in escherichia coli and purified to electrophoretic homogeneity after a combination of adsorption, ion-exchange and gel-filtration chromatography. the n-terminal signal sequence of the ftf was removed by e. coli at the same site as in its natural host. the purified ftf exhibited maximum activity at ph 6.0 and 37 degrees c, was activated by ca2+, but inhibited by the metal ions cu2+, zn2+, hg2+ and fe3+. the enzy ... | 1999 | 10393084 |
| pancreatic abscess due to streptococcus salivarius after dental manipulation. | 1999 | 10406286 | |
| starter culture activity in refrigerated fermented soymilk. | the refrigerated shelf life of soymilk fermented with single cultures of lactobacillus fermentum, l. casei, streptococcus salivarius subsp. thermophilus, and bifidobacterium longum was evaluated. during storage at 4 degrees c for 28 days, the stability of the microflora differed markedly among the starter cultures. after 28 days, the average numbers of s. salivarius subsp. thermophilus decreased by two log cycles to 6.0 x 10(7) cfu/ml, whereas those of l. casei increased gradually by more than t ... | 1999 | 10419278 |
| behavior of enterotoxigenic strains of staphylococcus aureus in milk fermented with a yogurt starter culture. | the ability of a yogurt starter culture formed by streptococcus salivarius subsp. thermophilus and lactobacillus delbrueckii subsp bulgaricus to inhibit the growth of four enterotoxin type a and b producers staphylococcus aureus strains (atcc 6538, s6, fri-100 and a strain isolated from milk) during fermentation of milk and subsequent storage was investigated. sterile skim milk was inoculated with about 10(6) cfu/ml of s. aureus and with about 10(6) cfu of starter culture, and incubated at 42 de ... | 1999 | 10932746 |
| influence of the oral administration of lactic acid bacteria on iga producing cells associated to bronchus. | intestinal, respiratory and genitourinary mucosal surfaces are the most important routes of entry for microbial pathogens. the stimulus of the mucosal immunity is not easy because the trigger keys for the activation do not follow the ones of the systemic immune response. in previous works we have demonstrated that some lactic acid bacteria (lab), when orally administered, can induce an enhance of the gut immune response. taking into account the concept of a common mucosal response, we studied th ... | 1999 | 12783652 |
| bacteria used for the production of yogurt inactivate carcinogens and prevent dna damage in the colon of rats. | lactic acid-producing bacteria prevent carcinogen-induced preneoplastic lesions and tumors in rat colon. because the mechanisms responsible for these protective effects are unknown, two strains of lactic acid bacteria, lactobacillus delbrueckii ssp. bulgaricus 191r and streptococcus salivarius ssp. thermophilus ch3, that are used to produce yogurt, were investigated in vitro and in vivo to elucidate their potential to deactivate carcinogens. using the "comet assay" to detect genetic damage, we f ... | 1999 | 9915879 |
| the hpr(ser) kinase of streptococcus salivarius: purification, properties, and cloning of the hprk gene. | in gram-positive bacteria, hpr, a protein of the phosphoenolpyruvate:sugar phosphotransferase system, is phosphorylated on a serine residue at position 46 by an atp-dependent protein kinase. the hpr(ser) kinase of streptococcus salivarius atcc 25975 was purified, and the encoding gene (hprk) was cloned by using a nucleotide probe designed from the n-terminal amino acid sequence. the predicted amino acid sequence of the s. salivarius enzyme showed 45% identity with the bacillus subtilis enzyme, t ... | 1999 | 9922231 |
| ctsr, a novel regulator of stress and heat shock response, controls clp and molecular chaperone gene expression in gram-positive bacteria. | clpp and clpc of bacillus subtillis encode subunits of the clp atp-dependent protease and are required for stress survival, including growth at high temperature. they play essential roles in stationary phase adaptive responses such as the competence and sporulation developmental pathways, and belong to the so-called class iii group of heat shock genes, whose mode of regulation is unknown and whose expression is induced by heat shock or general stress conditions. the product of ctsr, the first ge ... | 1999 | 9987115 |
| effect of steam sterilization inside the turbine chambers of dental turbines. | it has been demonstrated that contamination of the insides of high-speed dental turbines occurs and that bacteria as well as viruses may remain infectious when expelled from such turbines during subsequent use. consequently, it has been widely recommended that a high-speed turbine be sterilized after each patient. the purpose of this study was to evaluate the effect of steam autoclaving on a high-speed dental turbine with a contaminated turbine chamber. | 1999 | 10052374 |
| note: evaluation of selective media for the enumeration of bifidobacterium sp. in milk. | pure cultures of three species of bifidobacteria (bifidobacterium longum, bif. adolescentis and bif. bifidum), lactobacillus acidophilus and a mixed culture of lact. delbrueckii subsp. bulgaricus and streptococcus salivarius subsp. thermophilus were each enumerated on two differential media and six selective media for the enumeration of bifidobacteria. the appearance of the colonies on the differential media was as expected but when mixed cultures were present, it proved extremely difficult to d ... | 1999 | 10063635 |
| impact on the composition of the faecal flora by a new probiotic preparation: preliminary data on maintenance treatment of patients with ulcerative colitis. | although 5-aminosalicylic acid (5-asa) oral compounds are the standard maintenance treatment for ulcerative colitis in remission, some patients cannot use them because of side-effects. clinical and experimental observations have suggested the potential role of probiotics in inflammatory bowel disease therapy. | 1999 | 10468688 |
| an effective strategy, applicable to streptococcus salivarius and related bacteria, to enhance or confer electroporation competence. | despite the large number of techniques available for transformation of bacteria, certain species and strains are still resistant to introduction of foreign dna. some oral streptococci are among the organisms that can be particularly difficult to transform. we performed a series of experiments that involved manipulation of growth and recovery media and cell wall weakening, in which the electroporation conditions, cell concentration, and type and concentration of the transforming plasmid were vari ... | 1999 | 10473378 |
| a comparison of mta, super-eba, composite and amalgam as root-end filling materials using a bacterial microleakage model. | the aim of this study was to compare traditional and newly developed root-end filling materials for resistance to bacterial microleakage. | 1999 | 10530207 |
| an evaluation of the action of different root canal irrigants on facultative aerobic-anaerobic, obligate anaerobic, and microaerophilic bacteria. | the aim of this study was to test the effect of different concentrations of sodium hypochlorite, chlorhexidine, and cetrimide on the following bacterial strains: facultative aerobes-anaerobes: candida albicans atcc 10231; enterococcus faecalis atcc 29212; escherichia coli atcc 25,922; pseudomonas aeruginosa atcc 27,853; streptococcus mitis atcc 9811; streptococcus mutans atcc 35668; streptococcus salivarius atcc 13419; and streptococcus sanguis atcc 10556. microaerophiles: actinobacillus actinom ... | 1999 | 10530260 |
| mutation of aspartic acid residues in the fructosyltransferase of streptococcus salivarius atcc 25975. | the site-directed mutated fructosyltransferases (ftfs) of streptococcus salivarius atcc 25975, d312e, d312s, d312n and d312k were all active at 37 degrees c, indicating that asp-312 present in the 'sucrose box' was not the nucleophilic asp residue responsible for the formation of a covalent fructosyl-enzyme intermediate required for enzyme activity. analysis of the kinetic constants of the purified mutated forms of the enzyme showed that asp-312 was most likely an essential amino acid involved i ... | 1999 | 10548559 |
| membrane locus and ph sensitivity of paraben inhibition of alkali production by oral streptococci. | parabens were found to be potent inhibitors of alkali production from arginine by oral streptococci such as streptococcus rattus, streptococcus sanguis and streptococcus gordonii. for example, 2 mumol butylparaben per ml completely and irreversibly inhibited arginolysis by intact cells of s. rattus fa-1 and was lethal for the organism. in contrast, butylparaben was not a very effective inhibitor of ureolysis by intact cells of streptococcus salivarius 57.i, although it did kill the cells. butylp ... | 1999 | 10551169 |
| identification of clinically relevant viridans streptococci by analysis of transfer dna intergenic spacer length polymorphism. | the utility of pcr analysis of transfer dna intergenic spacer length polymorphism (tdna-ilp) for the identification to the species level of clinically relevant viridans streptococci was evaluated with a collection of reference strains of 15 species of the salivarius, anginosus, mitis and mutans rrna homology groups. pcr products generated by using fluorescent, outwardly directed, consensus tdna primers were analysed by electrophoresis on denaturating polyacrylamide gels and by laser fluorescence ... | 1999 | 10555340 |
| phenotypic consequences resulting from a methionine-to-valine substitution at position 48 in the hpr protein of streptococcus salivarius. | in gram-positive bacteria, the hpr protein of the phosphoenolpyruvate:sugar phosphotransferase system (pts) can be phosphorylated on a histidine residue at position 15 (his(15)) by enzyme i (ei) of the pts and on a serine residue at position 46 (ser(46)) by an atp-dependent protein kinase (his approximately p and ser-p, respectively). we have isolated from streptococcus salivarius atcc 25975, by independent selection from separate cultures, two spontaneous mutants (ga3.78 and ga3.14) that posses ... | 1999 | 10559156 |
| a new alkaline ph-adjusted medium enhances detection of beta-hemolytic streptococci by minimizing bacterial interference due to streptococcus salivarius. | a new selective medium (cna-p) that reduces or eliminates the inhibitory activity of bacteriocin-producing streptococcus salivarius against beta-hemolytic streptococci has been developed and compared with sheep blood agar (sba) for the sensitive detection of small numbers of beta-hemolytic streptococci in clinical specimens. cna-p has as its basis a commercial medium (difco columbia cna agar) supplemented with 5% (vol/vol) sheep blood, and the cna is further modified by addition of 100 mm pipes ... | 2000 | 10655361 |
| composition of the oral streptococcal flora in healthy children. | to identify the predominant streptococcal species in the mouths of healthy children and to investigate the composition of the oral streptococcal flora over a period of 4 months. | 2000 | 10666961 |
| quantification of micro-organisms in binary mixed populations by fourier transform infrared (ft-ir) spectroscopy. | fourier transform infrared (ft-ir) spectroscopy was used for the first time to determine the ratios of different microorganisms in mixtures. exemplarily, systems composed of two food-associated yeast species (saccharomyces cerevisiae/hanseniaspora uvarum) and two yoghurt lactic acid bacteria (lactobacillus acidophilus/streptococcus salivarius ssp. thermophilus) were investigated. determination of the cell number ratio in the lactic acid bacteria system was possible with a minimal prediction accu ... | 2000 | 10728568 |
| the gene encoding iiab(man)l in streptococcus salivarius is part of a tetracistronic operon encoding a phosphoenolpyruvate: mannose/glucose phosphotransferase system. | glucose and mannose are transported in streptococci by the mannose-pts (phosphoenolpyruvate:mannose phosphotransferase system), which consists of a cytoplasmic iiab protein, called iiab(man), and an uncharacterized membrane permease. this paper reports the characterization of the man operon encoding the specific components of the mannose-pts of streptococcus salivarius. the man operon was composed of four genes, manl, manm, mann and mano. these genes were transcribed from a canonical promoter (p ... | 2000 | 10746771 |
| characterization of recombinant, ureolytic streptococcus mutans demonstrates an inverse relationship between dental plaque ureolytic capacity and cariogenicity. | dental caries results from prolonged plaque acidification that leads to the establishment of a cariogenic microflora and demineralization of the tooth. urease enzymes of oral bacteria hydrolyze urea to ammonia, which can neutralize plaque acids. to begin to examine the relationship between plaque ureolytic activity and the incidence of dental caries, recombinant, ureolytic strains of streptococcus mutans were constructed. specifically, the ureabcefgd operon from streptococcus salivarius 57.i was ... | 2000 | 10768953 |
| direct probing by atomic force microscopy of the cell surface softness of a fibrillated and nonfibrillated oral streptococcal strain. | in this paper, direct measurement by atomic force microscopy (afm) of the cell surface softness of a fibrillated oral streptococcal strain streptococcus salivarius hb and of a nonfibrillated strain s. salivarius hbc12 is presented, and the data interpretation is validated by comparison with results from independent techniques. upon approach of the fibrillated strain in water, the afm tip experienced a long-range repulsion force, starting at approximately 100 nm, attributed to the compression of ... | 2000 | 10777762 |
| probiotic culture survival and implications in fermented frozen yogurt characteristics. | low-fat ice cream mix was fermented with probiotic-supplemented and traditional starter culture systems and evaluated for culture survival, composition, and sensory characteristics of frozen product. fermentations were stopped when the titratable acidity reached 0.15% greater than the initial titratable acidity (end point 1) or when the ph reached 5.6 (end point 2). mix was frozen and stored for 11 wk at -20 degrees c. the traditional yogurt culture system contained the strains streptococcus sal ... | 2000 | 10791781 |
| inactivation of the ptsi gene encoding enzyme i of the sugar phosphotransferase system of streptococcus salivarius: effects on growth and urease expression. | the urease genes of streptococcus salivarius 57.1 are tightly repressed in cells growing at neutral ph. when cells are cultivated at acidic ph values, the urease genes become derepressed and transcription is enhanced when cells are growing under carbohydrate-excess conditions. previously, the authors proposed that the bacterial sugar:phosphotransferase system (pts) modulated the dna-binding activity by phosphorylation of the urease repressor when carbohydrate was limiting. the purpose of this st ... | 2000 | 10832646 |
| ib-367, a protegrin peptide with in vitro and in vivo activities against the microflora associated with oral mucositis. | although the microflora associated with oral mucositis initiated by cytotoxic therapy is not well characterized, several studies suggest that reduction of the microbial load in the oral cavity has some clinical benefit. the mics of ib-367, a synthetic protegrin analog, ranged from 0.13 to 64 microgram/ml for gram-positive bacteria (streptococcus mitis, streptococcus sanguis, streptococcus salivarius, and staphylococcus aureus) and from 0.06 to 8 microgram/ml for gram-negative species (klebsiella ... | 2000 | 10858334 |
| absence of a putative mannose-specific phosphotransferase system enzyme iiab component in a leucocin a-resistant strain of listeria monocytogenes, as shown by two-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis. | leucocin a is a class iia bacteriocin produced by leuconostoc spp. that has previously been shown to inhibit the growth of listeria monocytogenes. a spontaneous resistant mutant of l. monocytogenes was isolated and found to be resistant to leucocin a at levels in excess of 2 mg/ml. the mutant showed no significant cross-resistance to nontype iia bacteriocins including nisaplin and esf1-7gr. however, there were no inhibition zones found on a lawn of the mutant when challenged with an extract cont ... | 2000 | 10877813 |
| streptococcus salivarius acute meningitis with latent petromastoiditis. | a 48-y-old woman, with a previous history of neurosurgical intervention for a trigeminal neurinoma, presented with acute meningitis due to streptococcus salivarius. there were significant changes in the petrous region, as revealed by mri, leading to the diagnosis of associated latent subacute mastoiditis. | 2000 | 10879608 |
| dual functions of streptococcus salivarius urease. | a urease-deficient derivative of streptococcus salivarius 57.i was constructed by allelic exchange at the urec locus. the wild-type strain was protected against acid killing through hydrolysis of physiologically relevant concentrations of urea, whereas the mutant was not. also, s. salivarius could use urea as a source of nitrogen for growth exclusively through a urease-dependent pathway. | 2000 | 10913107 |
| low frequency of bacteremia after endoscopic mucosal resection. | endoscopic mucosal resection has become a popular alternative for the treatment of early-stage neoplasia of the gastrointestinal tract. however, there are still no data on the frequency of bacteremia associated with this form of treatment. | 2000 | 10922095 |
| oral bacteriotherapy as maintenance treatment in patients with chronic pouchitis: a double-blind, placebo-controlled trial. | pouchitis is the major long-term complication after ileal pouch-anal anastomosis for ulcerative colitis. most patients have relapsing disease, and no maintenance treatment study has been performed. we evaluated the efficacy of a probiotic preparation (vsl#3) containing 5 x 10(11) per gram of viable lyophilized bacteria of 4 strains of lactobacilli, 3 strains of bifidobacteria, and 1 strain of streptococcus salivarius subsp. thermophilus compared with placebo in maintenance of remission of chroni ... | 2000 | 10930365 |
| an evaluation of resin-ionomers to prevent coronal microleakage in endodontically treated teeth. | while a gutta-percha system is most commonly used by practitioners for canal obturation, there is no agreement on how best to close the chamber of an endodontically treated tooth. some materials used in restorative dentistry may have endodontic applications. restorative materials of particular interest to endodontists are those used as subgingival restorations. their properties include insolubility in oral fluids, adhesiveness, dual-cure capabilities, radiopacity, hardness and fluoride release, ... | 2000 | 11460288 |
| nucleotide sequence, expression and transcriptional analysis of the bifidobacterium longum mb 219 lacz gene. | the gene encoding beta-galactosidase was isolated by functional complementation of escherichia coli from bifidobacterium longum mb219, which exhibited the highest activity among ten bifidobacterium strains tested of the species b. longum, b. breve, b. adolescentis, b. indicum, b. animalis and b. cuniculi. the nucleotide sequence of the 5.0-kb fragment conferring the positive beta-galactosidase phenotype to e. coli revealed the presence of a lacz-type gene encoding a 1023-amino-acid protein that ... | 2000 | 10985745 |
| regulation of the pts operon in low g+c gram-positive bacteria. | the sugar transport system called phosphoenolpyruvate: sugar phosphotransferase (pts) is widespread among eubacteria. its is generally composed of two cytoplasmic proteins, hpr and el, which are found in all bacteria possessing a pts, and a family of ells whose number, specificity, and molecular structure in terms of domain arrangement vary from species to species. in low g+c gram-positive bacteria, the genes coding for the general proteins hpr and el, designated ptsh and ptsl respectively, are ... | 2000 | 11075921 |
| the galu gene of streptococcus pneumoniae that codes for a udp-glucose pyrophosphorylase is highly polymorphic and suitable for molecular typing and phylogenetic studies. | the enzyme utp-glucose-1-phosphate uridylyltransferase (udp-glucose pyrophosphorylase, udpg:pp) is synthesized by practically all organisms, although prokaryotic udpg:pps are evolutionarily unrelated to the eukaryotic counterparts. the primary structure of prokaryotic udpg:pps is well conserved, although little information exists on the polymorphism of the genes coding for these enzymes. it has been reported that the galu gene encoding the streptococcus pneumoniae udpg:pp is absolutely required ... | 2000 | 11137293 |
| production and monomer composition of exopolysaccharides by yogurt starter cultures. | as components of starter cultures for bulgarian yogurt, streptococcus salivarius subsp. thermophilus and lactobacillus delbrueckii subsp. bulgaricus revealed extensive exopolysaccharide (eps) production activity when cultivated in whole cow's milk. the polymer-forming activity of thermophilic streptococci was lower (230-270 mg eps/l) than that of the lactobacilli (400-540 mg eps/l). mixed cultures stimulated eps production in yogurt manufacture, and a maximum concentration of 720-860 mg eps/l wa ... | 2000 | 11142402 |
| the oral microbiota of children undergoing liver transplantation. | this study investigated the oral microbiota of children undergoing liver transplantation. oral swabs were taken using a standardized procedure from 27 children before liver transplantation and at 3 and 100 days post-transplantation and from 27 healthy controls at baseline and 90 days. viridans streptococci, yeasts, staphylococci, enterococci and enterobacteriaceae were enumerated and identified using conventional techniques. the oral microbiota of the patients changed significantly immediately p ... | 2000 | 11154404 |
| suppression of urease levels in streptococcus salivarius by cysteine, related compounds and by sulfide. | urease synthesis in streptococcus salivarius is induced by an acid environment, carbohydrate and a high growth rate. we now report that both cysteine and sulfide above 1 mm strongly suppress s. salivarius urease levels. close structural relatives of cysteine (cysteamine, ethanedithiol and penicillamine) at 5 mm buffered to ph 7.0 also caused urease suppression, but thiols in general (2-mercaptoethanol, dithiothreitol and glutathione) did not. in cultures buffered below ph 5.9, the cysteine-induc ... | 2000 | 11154424 |
| iatrogenic meningitis: an increasing role for resistant viridans streptococci? case report and review of the last 20 years. | iatrogenic meningitis following lumbar puncture is a rare event. we present a 52-y-old man who developed symptoms of meningitis within 12 h after spinal anaesthesia. cerebrospinal fluid cultures grew streptococcus salivarius partially resistant to penicillin and ceftriaxone. the patient was successfully treated with ceftriaxone and vancomycin and left the hospital with minor sequelae. a literature review of 60 cases revealed the median age of the patients to be 44 y. the median incubation period ... | 2000 | 11200384 |
| regulation of urease gene expression by streptococcus salivarius growing in biofilms. | the metabolism of urea by urease enzymes of oral bacteria profoundly influences oral biofilm ph homeostasis and oral microbial ecology. the purpose of this study was to gain insight into the regulation of expression of the low ph-inducible urease genes in populations of streptococcus salivarius growing in vitro in biofilms and to explore whether urease regulation or the levels of urease expression in biofilm cells differed significantly from planktonic cells. two strains of s. salivarius harbour ... | 2000 | 11220303 |
| disinfection of dental impressions and occlusal records by ultraviolet radiation. | as chemical disinfection of dental impressions may cause adverse effects on materials and the dental personnel this study examined disinfection by ultraviolet radiation. alginate, addition silicone rubber and red wax contaminated by streptococcus salivarius, fusobacterium nucleatum and five other bacteria in different suspension media were radiated for up to 18 min, and the number of colony forming units was compared to non-radiated controls. the effect of ultraviolet radiation differed among ba ... | 2000 | 11307403 |
| intra- and interspecies signaling between streptococcus salivarius and streptococcus pyogenes mediated by sala and sala1 lantibiotic peptides. | streptococcus salivarius 20p3 produces a 22-amino-acid residue lantibiotic, designated salivaricin a (sala), that inhibits the growth of a range of streptococci, including all strains of streptococcus pyogenes. lantibiotic production is associated with the sal genetic locus comprising sala, the lantibiotic structural gene; salbctx genes encoding peptide modification and export machinery proteins; and salykr genes encoding a putative immunity protein and two-component sensor-regulator system. ins ... | 2001 | 11395456 |
| the effect of oral bacteria on candida albicans germ-tube formation. | a total of eight bacterial isolates belonging to six species, and a select group of 12 oral candida albicans isolates, were used to study the effect of bacteria on germ-tube formation. briefly, each bacterial suspension (10(5-6) cells/ml) was mixed with a c. albicans suspension (10(7) cells/ml) and incubated at 37 degrees c for 90 min with bovine serum, and the percentage germ-tube-positive candida cells was quantified using a haemocytometer, under light microscopy. in general, out of eight bact ... | 2001 | 11398996 |
| isolation and characterization of a streptococcus thermophilus plasmid closely related to the pmv158 family. | twenty-two streptococcus thermophilus strains used for milk fermentations were analyzed for their plasmid content and 13 of them (59%) were found to contain one or two plasmids. fifteen s. thermophilus plasmids were divided into four groups using dna homology. ten plasmids were classified within group a and they shared homologies with all the previously sequenced s. thermophilus plasmids. three plasmids (group b) hybridized with each other and two plasmids only hybridized with themselves (groups ... | 2001 | 11407913 |
| identification of streptococcus salivarius by pcr and dna probe. | to establish species-specific pcr and dna probe methods for streptococcus salivarius and to clarify the distribution of dextranase in oral isolates of strep. salivarius. | 2001 | 11412350 |
| ecological effects on the oro- and nasopharyngeal microflora in children after treatment of acute otitis media with cefuroxime axetil or amoxycillin-clavulanate as suspensions. | to evaluate if the extent of normal microflora disturbances differed between treatment with amoxycillin-clavulanate administered in an active form and cefuroxime axetil administered as an inactive prodrug. | 2001 | 11422249 |
| inhibitory effects of moabs against a surface protein antigen in real-time adherence in vitro and recolonization in vivo of streptococcus mutans. | a surface protein antigen (pac) of streptococcus mutans, particularly the a-region of the molecule, has been reported to interact with salivary components on the tooth surface. it might be a candidate antigen inducing the production of antibodies against the adherence of s. mutans to the tooth surface. we investigated the effects of monoclonal antibodies (moabs) obtained by immunization of synthetic pac peptides that completely correspond to the amino acid sequence of part of the a-region. these ... | 2001 | 11439156 |
| sites of ph regulation of the urea channel of helicobacter pylori. | helicobacter pylori (hp) and streptococcus salivarius (ss) require intrabacterial urease for acid resistance and express a urea channel, urei. the presence of urei was shown to increase urea permeability approximately 300-fold over that of a non-polar urei deletion mutant. expression of ssurei in xenopus oocytes increased urea uptake ph independently, whereas hpurei shows an acidic ph dependence, half-maximal at ph 6.0. mutagenesis of all histidines, aspartates, glutamates and the lysine in the ... | 2001 | 11442825 |
| acetaldehyde production and other adh-related characteristics of aerobic bacteria isolated from hypochlorhydric human stomach. | acetaldehyde is a known local carcinogen in the digestive tract in humans. bacterial overgrowth in the hypochlorhydric stomach enhances production of acetaldehyde from ethanol in vivo after alcohol ingestion. therefore, microbially produced acetaldehyde may be a potential risk factor for alcohol-related gastric and cardiac cancers. this study was aimed to investigate which bacterial species and/or groups are responsible for acetaldehyde formation in the hypochlorhydric human stomach and to chara ... | 2001 | 11290854 |
| streptococcus salivarius fimbriae are composed of a glycoprotein containing a repeated motif assembled into a filamentous nondissociable structure. | streptococcus salivarius, a gram-positive bacterium found in the human oral cavity, expresses flexible peritrichous fimbriae. in this paper, we report purification and partial characterization of s. salivarius fimbriae. fimbriae were extracted by shearing the cell surface of hyperfimbriated mutant a37 (a spontaneous mutant of s. salivarius atcc 25975) with glass beads. preliminary experiments showed that s. salivarius fimbriae did not dissociate when they were incubated at 100 degrees c in the p ... | 2001 | 11292790 |
| electrostatic interactions in the adhesion of an ion-penetrable and ion-impenetrable bacterial strain to glass. | deposition to glass of streptococcus salivarius hb-c12 and staphylococcus epidermidis 3399 in a parallel plate flow chamber has been studied as a function of ionic strength. electrophoretic mobility measurements revealed that s. epidermidis 3399 possesses a thick ion-penetrable layer, probably associated with its encapsulation, while s. salivarius hb-c12 has an ion-impenetrable surface. streaming potential measurements indicated that also the glass surface was covered with a relatively thin, ion ... | 2001 | 11087983 |
| lack of effect of an externally applied electric field on bacterial adhesion to glass. | deposition to glass of streptococcus salivarius hb-c12 and staphylococcus epidermidis 3399 in a parallel plate flow chamber in the absence and presence of an externally applied electric field has been studied experimentally. no effect on bacterial adhesion, including initial deposition rates, numbers of adhering bacteria after 4 h, spatial distributions of adhering bacteria and air bubble induced detachment, was found. a theoretical analysis shows that electric fields applied over a 150 µm thin ... | 2001 | 11087991 |
| bactericidal and cytotoxic effects of sodium hypochlorite and sodium dichloroisocyanurate solutions in vitro. | the antimicrobial and cytotoxic effects of sodium hypochlorite (naocl) and sodium dichloroisocyanurate (nadcc) were evaluated and compared in vitro. the minimal inhibitory concentration and minimal bactericidal concentration of naocl and nadcc were tested for streptococcus sobrinus, streptococcus salivarius, enterococcus faecalis, and streptococcus mutans. the cytotoxic effect was assessed by using human fibroblast tissue culture. survival rate was assessed by a protein determination method. res ... | 2001 | 11485267 |
| diversity of streptococcus salivarius ptsh mutants that can be isolated in the presence of 2-deoxyglucose and galactose and characterization of two mutants synthesizing reduced levels of hpr, a phosphocarrier of the phosphoenolpyruvate:sugar phosphotransferase system. | in streptococci, hpr, a phosphocarrier of the phosphoenolpyruvate:sugar phosphotransferase transport system (pts), undergoes multiple posttranslational chemical modifications resulting in the formation of hpr(his approximately p), hpr(ser-p), and hpr(ser-p)(his approximately p), whose cellular concentrations vary with growth conditions. distinct physiological functions are associated with specific forms of hpr. we do not know, however, the cellular thresholds below which these forms become unabl ... | 2001 | 11489868 |
| meningitis due to streptococcus salivarius. | 2001 | 11499393 | |
| [viability and activity of the lactic bacteria (streptococcus salivarius ssp thermophilus y lactobacillus delbrueckii ssp bulgaricus) del yogurt en venezuela]. | national and international legislations have agreed that the population of lactic bacteria in yogurt must be viable and not less than 10(6) ufc/g. in venezuela, during last years, observations indicate that the number of viable cells in some commercial samples show high variations, as low levels. this research attempted to find the origin of this problem in the local industry. for this purpose 105 commercial samples were analyzed during their shelf life and 32 samples of yogurt prepared in the l ... | 2001 | 11510428 |
| alteration of the coadherence of candida albicans with oral bacteria by dietary sugars. | interactions between bacterial oral flora and candida albicans are important in denture plaque formation. this study therefore first aimed to quantify the coadherence of c. albicans and bacteria by the use of a bioluminescent adenosine triphosphate (atp) assay based on the firefly luciferase-luciferin system. the second aim was to examine the effect of i) dietary sugars (used for preculture) and ii) enzymatic digestion of fungi on the coadherence. when yeast was preincubated in yeast nitrogen ba ... | 2001 | 11555304 |
| in vitro antimicrobial activities of bakuchiol against oral microorganisms. | bakuchiol was isolated from the seeds of psoralea corylifolia, a tree native to china with various uses in traditional medicine, followed by extraction with ether and column chromatography combined with silica gel and octyldecyl silane. in this study, the antimicrobial activities of bakuchiol against some oral microorganisms were evaluated in vitro. the cell growth of streptococcus mutans was inhibited in a bakuchiol concentration-dependent manner, and growth of s. mutans was completely prevente ... | 2001 | 11600349 |
| prediction of streptococcus salivarius subsp. thermophilus and lactobacillus delbrueckii subsp. bulgaricus populations in yoghurt by curie point pyrolysis-mass spectrometry. | we evaluated the potential of pyrolysis-mass spectrometry (pyms) for quantifying the binary mixed population of streptococcus salivarius subsp. thermophilus and lactobacillus delbrueckii subsp. bulgaricus in yoghurt. for this purpose, a new analytical approach was developed. the yoghurt was transparised and its total bacterial population was recovered by centrifugation and estimated by turbidimetric measurement. the quantity of each population (l. bulgaricus, s. thermophilus) was then estimated ... | 2002 | 11777575 |
| galactose and lactose genes from the galactose-positive bacterium streptococcus salivarius and the phylogenetically related galactose-negative bacterium streptococcus thermophilus: organization, sequence, transcription, and activity of the gal gene products. | streptococcus salivarius is a lactose- and galactose-positive bacterium that is phylogenetically closely related to streptococcus thermophilus, a bacterium that metabolizes lactose but not galactose. in this paper, we report a comparative characterization of the s. salivarius and s. thermophilus gal-lac gene clusters. the clusters have the same organization with the order galr (codes for a transcriptional regulator and is transcribed in the opposite direction), galk (galactokinase), galt (galact ... | 2002 | 11790749 |
| inhibitory effect of zncl(2) on glycolysis in human oral microbes. | although the inhibition of bacterial glycolysis by zinc ions might be expected to moderate dental caries, there has not been a comparison of the effect of zn on different organisms under both fixed ph and free-fall conditions. here, the effect of zncl(2) on streptococcus salivarius, strep. mutans, strep. sobrinus, actinomyces naeslundii and lactobacillus casei, as well as on mixtures of oral organisms outgrown from human dental plaque and saliva, was surveyed. ph-stat experiments were performed ... | 2002 | 11825576 |
| role of the c-terminal yg repeats of the primer-dependent streptococcal glucosyltransferase, gtfj, in binding to dextran and mutan. | the recombinant primer-dependent glucosyltransferase gtfj of streptococcus salivarius possesses a c-terminal glucan-binding domain composed of eighteen 21 aa yg repeats. by engineering a series of c-terminal truncated proteins, the position at which truncation prevented further mutan synthesis was defined to a region of 43 aa, confirming that not all of the yg motifs were required for the formation of mutan by gtfj. the role of the yg repeats in glucan binding was investigated in detail. three p ... | 2002 | 11832518 |
| [streptococcus salivarius meningitis after oral trauma by a skewer: a case report]. | although streptococcus salivarius is one of the normal flora in the oral cavity and gastrointestinal tract, the agent may cause bacteremia, meningitis, endocarditis and sinusitis under certain circumstances. we report a 3-year-old female with meningitis after oral trauma by a skewer due to penicillin resistant s. salivarius. the girl injured her throat accidentally with a skewer. four hours later, she became febrile and came to our emergency room. plain ct scan was normal, and cefalexin was pres ... | 2002 | 11852478 |
| three cases of bacterial meningitis after spinal and epidural anesthesia. | during a 3-year period, three cases of bacterial meningitis developing after spinal or epidural anesthesia were observed at one hospital in germany. the causative organisms were streptococcus salivarius (2 cases) and staphylococcus aureus (1 case). in the first two cases, contamination of the needle by oropharyngeal flora of the anesthesiological team was likely but remained unproven. in the third case, a nasal swab obtained from the operating anesthesiologist yielded a staphylococcus aureus str ... | 2002 | 11913500 |
| simulation modelling of bacterial growth in yoghurt. | indisim, an individual-based simulator, was used to specifically study the influence of the shape and size of streptococcus salivarius subsp. thermophilus and lactobacillus delbrueckii subsp. bulgaricus in yoghurt processing. to this effect, two different sets of simulations were carried out. in the first set of simulations, it was assumed that the initial acidity of the medium has the same value as the acidity of the cytoplasm of the microorganisms. hence, the differences in bacterial growth by ... | 2002 | 11934049 |
| [multimicrobial endocarditis caused by streptococcus salivarius and pseudomonas stutzeri: good course after early surgery]. | 2002 | 11989087 | |
| pathways for lactose/galactose catabolism by streptococcus salivarius. | galactokinase and beta-galactosidase-deficient strains of streptococcus salivarius were constructed to define the pathways for lactose and galactose catabolism. it was found that s. salivarius does not possess a lactose-specific phosphoenolpyruvate phosphotransferase system (pts), that intracellular lactose was hydrolyzed by beta-galactosidase, and that galactose is catabolized exclusively through the leloir pathway. the lack of a high-affinity pts for lactose may reflect the higher availability ... | 2002 | 12007657 |
| behavior of listeria monocytogenes and staphylococcus aureus in yogurt fermented with a bacteriocin-producing thermophilic starter. | streptococcus salivarius subsp. thermophilus b producing a bacteriocin active against listeria monocytogenes atcc 7644 and staphylococcus aureus sad 30 was isolated from bakery yeast. the bacteriocin was partially purified by an adsorption/desorption technique, and its spectrum of action was compared to that of a neutralized cell-free supernatant (cfs). although the cfs inhibited a number of gram-positive and -negative bacteria of health and spoilage significance, the spectrum of action of the p ... | 2002 | 12030291 |
| an essential amino acid residue for catalytic activity of the dextranase of streptococcus mutans. | dextranase (dex) is an enzyme that hydrolyzes glucan, a polymer of glucose synthesized from sucrose by glucosyltransferases (gtfs). by comparing amino acid sequences of dexs and gtfs, we found that the dex enzymes of streptococcus mutans, streptococcus sobrinus, streptococcus downei and streptococcus salivarius had similar amino acid sequences to those of the catalytic sites of gtfs of mutans streptococci. we therefore examined the amino acid essential in dex catalysis by molecular genetic appro ... | 2002 | 12030973 |