Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
|---|
| axenic culture of a candidate division tm7 bacterium from the human oral cavity and biofilm interactions with other oral bacteria. | the diversity of bacterial species in the human oral cavity is well recognized, but a high proportion of them are presently uncultivable. candidate division tm7 bacteria are almost always detected in metagenomic studies but have not yet been cultivated. in this paper, we identified candidate division tm7 bacterial phylotypes in mature plaque samples from around orthodontic bonds in subjects undergoing orthodontic treatment. successive rounds of enrichment in laboratory media led to the isolation ... | 2014 | 25107981 |
| disruption of heterotypic community development by porphyromonas gingivalis with small molecule inhibitors. | porphyromonas gingivalis is one of the main etiological organisms in periodontal disease. on oral surfaces p. gingivalis is a component of multispecies biofilm communities and can modify the pathogenic potential of the community as a whole. accumulation of p. gingivalis in communities is facilitated by interspecies binding and communication with the antecedent colonizer streptococcus gordonii. in this study we screened a library of small molecules to identify structures that could serve as lead ... | 2014 | 24899524 |
| characterization of a bacterial tyrosine kinase in porphyromonas gingivalis involved in polymicrobial synergy. | interspecies communication between porphyromonas gingivalis and streptococcus gordonii underlies the development of synergistic dual species communities. contact with s. gordonii initiates signal transduction within p. gingivalis that is based on protein tyrosine (de)phosphorylation. in this study, we characterize a bacterial tyrosine (by) kinase (designated ptk1) of p. gingivalis and demonstrate its involvement in interspecies signaling. ptk1 can utilize atp for autophosphorylation and is depho ... | 2014 | 24811194 |
| silver-zeolite combined to polyphenol-rich extracts of ascophyllum nodosum: potential active role in prevention of periodontal diseases. | the purpose of this study was to evaluate various biological effects of silver-zeolite and a polyphenol-rich extract of a. nodosum (ascop) to prevent and/or treat biofilm-related oral diseases. porphyromonas gingivalis and streptococcus gordonii contribute to the biofilm formation associated with chronic periodontitis. in this study, we evaluated in vitro antibacterial and anti-biofilm effects of silver-zeolite (ag-zeolite) combined to ascop on p. gingivalis and s. gordonii growth and biofilm fo ... | 2014 | 25272151 |
| effects of nicotine on streptococcus gordonii growth, biofilm formation, and cell aggregation. | streptococcus gordonii is a commensal species of human oral flora. it initiates dental biofilm formation and provides binding sites for later colonizers to attach to and generate mature biofilm. smoking is the second highest risk factor for periodontal disease, and cigarette smoke extract has been reported to facilitate porphyromonas gingivalis-s. gordonii dual-species biofilm formation. our hypothesis is that nicotine, one of the most important and active components of tobacco, stimulates s. go ... | 2014 | 25217021 |
| antimicrobial gl13k peptide coatings killed and ruptured the wall of streptococcus gordonii and prevented formation and growth of biofilms. | infection is one of the most prevalent causes for dental implant failure. we have developed a novel antimicrobial peptide coating on titanium by immobilizing the antimicrobial peptide gl13k. gl13k was developed from the human salivary protein bpifa2. the peptide exhibited mic of 8 µg/ml against planktonic pseudonomas aeruginosa and their biofilms were reduced by three orders of magnitude with 100 µg/ml gl13k. this peptide concentration also killed 100% of streptococcus gordonii. at 1 mg/ml, gl13 ... | 2014 | 25372402 |
| proteomics of fusobacterium nucleatum within a model developing oral microbial community. | fusobacterium nucleatum is a common oral organism that can provide adhesive and metabolic support to developing periodontal bacterial communities. it is within the context of these communities that disease occurs. we have previously reported whole cell proteomics analyses of porphyromonas gingivalis and streptococcus gordonii in early-stage communities with each other and with f. nucleatum, modeled using 18 h pellets. here, we report the adaptation of f. nucleatum to the same experimental condit ... | 2014 | 25155235 |
| transduction of the streptococcus pyogenes bacteriophage φm46.1, carrying resistance genes mef(a) and tet(o), to other streptococcus species. | φm46.1 - streptococcus pyogenes bacteriophage carrying mef(a) and tet(o), respectively, encoding resistance to macrolides (m phenotype) and tetracycline - is widespread in s. pyogenes but has not been reported outside this species. φm46.1 is transferable in vitro among s. pyogenes isolates, but no information is available about its transferability to other streptococcus species. we thus investigated φm46.1 for its ability to be transduced in vitro to recipients of different streptococcus species ... | 2014 | 25620959 |
| amplification of bacteria-induced platelet activation is triggered by fcγriia, integrin αiibβ3, and platelet factor 4. | bacterial adhesion to platelets is mediated via a range of strain-specific bacterial surface proteins that bind to a variety of platelet receptors. it is unclear how these interactions lead to platelet activation. we demonstrate a critical role for the immune receptor fcγriia, αiibβ3, and src and syk tyrosine kinases in platelet activation by staphylococcus aureus, streptococcus sanguinis, streptococcus gordonii, streptococcus oralis, and streptococcus pneumoniae. fcγriia activation is dependent ... | 2014 | 24642751 |
| effective oral health in infective endocarditis: efficacy of high-street mouthwashes against the viridans group streptococci. | recent uk national institute for health and clinical excellence guidelines state that there is no longer a need for oral antibiotic prophylaxis in patients undergoing dental procedures who are at risk of infective endocarditis (ie), and advocate the importance of maintaining good oral health. as viridans group streptococci (vgs) are common etiological agents of ie and inhabitants of the mouth, the purpose of this study was to examine the efficacy of common high-street mouthwashes against four cl ... | 2014 | 24610586 |
| structure of the c-terminal domain of aspa (antigen i/ii-family) protein from streptococcus pyogenes. | the pathogenic bacteria streptococcus pyogenes can cause an array of diseases in humans, including moderate infections such as pharyngitis (strep throat) as well as life threatening conditions such as necrotizing fasciitis and puerperal fever. the antigen i/ii family proteins are cell wall anchored adhesin proteins found on the surfaces of most oral streptococci and are involved in host colonization and biofilm formation. in the present study we have determined the crystal structure of the c2-3- ... | 2014 | 24918040 |
| crystalline anatase-rich titanium can reduce adherence of oral streptococci. | dental implant abutments that emerge through the mucosa are rapidly covered with a salivary protein pellicle to which bacteria bind, initiating biofilm formation. in this study, adherence of early colonizing streptococci, streptococcus gordonii, streptococcus oralis, streptococcus mitis and streptococcus sanguinis to two saliva-coated anodically oxidized surfaces was compared with that on commercially pure titanium (cpti). near edge x-ray absorption (nexafs) showed crystalline anatase was more p ... | 2014 | 24881929 |
| the influence of oral veillonella species on biofilms formed by streptococcus species. | oral veillonella, veillonella atypica, veillonella denticariosi, veillonella dispar, veillonella parvula, veillonella rogosae, and veillonella tobetsuensis are known as early colonizers in oral biofilm formation. to investigate the role of oral veillonella, biofilms formed by the co-culture of streptococcus gordonii, streptococcus mutans, streptococcus salivarius, or streptococcus sanguinis, with oral veillonella were examined at the species level. the amount of biofilm formed by s. mutans, s. g ... | 2014 | 24862495 |
| identification and characterization of a salivary-pellicle-binding peptide by phage display. | dental biofilms are associated with oral diseases, making their control necessary. one way to control them is to prevent initial bacterial adherence to the salivary pellicle and thereby eventually decrease binding of late colonizing potential pathogens. the goal of this study was to generate a salivary-pellicle-binding peptide (spbp) with antifouling activity towards primary colonizing bacteria. in order to achieve this goal we aimed to: (i) identify novel spbps by phage display; (ii) characteri ... | 2014 | 24607635 |
| genetic basis of coaggregation receptor polysaccharide biosynthesis in streptococcus sanguinis and related species. | interbacterial adhesion between streptococci and actinomyces promotes early dental plaque biofilm development. recognition of coaggregation receptor polysaccharides (rps) on strains of streptococcus sanguinis, streptococcus gordonii and streptococcus oralis by actinomyces spp. type 2 fimbriae is the principal mechanism of these interactions. previous studies of genetic loci for synthesis of rps (rps) and rps precursors (rml, gale1 and gale2) in s. gordonii 38 and s. oralis 34 revealed difference ... | 2014 | 24397790 |
| mass spectrometric analysis of whole secretome and amylase-precipitated secretome proteins from streptococcus gordonii. | oral biofilm (dental plaque) is formed by the initial adhesion of "pioneer species" to salivary proteins that form the dental pellicle on the tooth surface. one such pioneer species, streptococcus gordonii, is known to bind salivary amylase through specific amylase-binding proteins such as amylase-binding protein a (abpa). recent studies have demonstrated that once bound, salivary amylase appears to modulate gene expression in s. gordonii. however, it is not known if this amylase-induced gene ex ... | 2014 | 25605983 |
| oral streptococci utilize a siglec-like domain of serine-rich repeat adhesins to preferentially target platelet sialoglycans in human blood. | damaged cardiac valves attract blood-borne bacteria, and infective endocarditis is often caused by viridans group streptococci. while such bacteria use multiple adhesins to maintain their normal oral commensal state, recognition of platelet sialoglycans provides an intermediary for binding to damaged valvular endocardium. we use a customized sialoglycan microarray to explore the varied binding properties of phylogenetically related serine-rich repeat adhesins, the gspb, hsa, and srpa homologs fr ... | 2014 | 25474103 |
| children with severe early childhood caries: streptococci genetic strains within carious and white spot lesions. | mutans streptococci (ms) are one of the major microbiological determinants of dental caries. the objectives of this study are to identify distinct ms and non-ms streptococci strains that are located at carious sites and non-carious enamel surfaces in children with severe early childhood caries (s-ecc), and assess if cariogenic ms and non-cariogenic streptococci might independently exist as primary bacterial strains on distinct sites within the dentition of individual children. | 2014 | 25405004 |
| comparison of genes required for h2o2 resistance in streptococcus gordonii and streptococcus sanguinis. | hydrogen peroxide (h2o2) is produced by several members of the genus streptococcus mainly through the pyruvate oxidase spxb under aerobic growth conditions. the acute toxic nature of h2o2 raises the interesting question of how streptococci cope with intrinsically produced h2o2, which subsequently accumulates in the microenvironment and threatens the closely surrounding population. here, we investigate the h2o2 susceptibility of oral streptococcus gordonii and streptococcus sanguinis and elucidat ... | 2014 | 25280752 |
| an insight into the exploration of druggable genome of streptococcus gordonii for the identification of novel therapeutic candidates. | the discovery of novel drug targets of a genome that can bind with high affinity to drug-like compounds is a significant challenge in drug development. streptococcus gordonii initiates dental plaque formation and endocarditis by entering into the blood stream, usually after oral trauma. the prolonged use of antibiotics is raising a problem of multi-drug resistance and lack of an optimal therapeutic regime that necessitates the drug discovery of vital importance in curing various infections. to o ... | 2014 | 25068724 |
| inhibition of initial bacterial adhesion on titanium surfaces by lactoferrin coating. | because dental implant abutments are located at transmucosal sites, their surface should inhibit bacterial accumulation to prevent peri-implantitis. the authors examined the effects of human lactoferrin (lf), an antibacterial protein present in saliva, as an antibacterial coating on the titanium surface and evaluated its effects before and after mucin-containing artificial saliva (as) incubation. in the control group, titanium disks were soaked in distilled water, whereas in the lf group, titani ... | 2014 | 24985210 |
| the calcium-induced conformation and glycosylation of scavenger-rich cysteine repeat (srcr) domains of glycoprotein 340 influence the high affinity interaction with antigen i/ii homologs. | oral streptococci adhere to tooth-immobilized glycoprotein 340 (gp340) via the surface protein antigen i/ii (agi/ii) and its homologs as the first step in pathogenesis. studying this interaction using recombinant proteins, we observed that calcium increases the conformational stability of the scavenger-rich cysteine repeat (srcrs) domains of gp340. our results also show that agi/ii adheres specifically with nanomolar affinity to the calcium-induced srcr conformation in an immobilized state and n ... | 2014 | 24923446 |
| poly(ethylene oxide)-b-poly(3-sulfopropyl methacrylate) block copolymers for calcium phosphate mineralization and biofilm inhibition. | poly(ethylene oxide) (peo) has long been used as an additive in toothpaste, partly because it reduces biofilm formation on teeth. it does not, however, reduce the formation of dental calculus or support the remineralization of dental enamel or dentine. the present article describes the synthesis of new block copolymers on the basis of peo and poly(3-sulfopropyl methacrylate) blocks using atom transfer radical polymerization. the polymers have very large molecular weights (over 10(6) g/mol) and a ... | 2014 | 25230392 |
| the presence and distribution of bacteria in dentinal tubules of root filled teeth. | to investigate the distribution of bacteria within the dentine tubular network in a two-chamber model in order to determine a possible route of penetration. | 2014 | 24111689 |
| levels and complexity of iga antibody against oral bacteria in samples of human colostrum. | streptococcus mutans (sm) have three main virulence antigens: glucan binding protein b (gbpb), glucosyltransferase (gtf) and antigens i/ii (ag i/ii) envolved in the capacity of those bacteria to adhere and accumulate in the dental biofilm. also, the glycosyltransferases 153 kda of streptococcus gordonii (sgo) and 170kda of streptococcus sanguinis (ssa) were important antigens associated with the accumulation of those bacterias. streptococcus mitis (smi) present iga1 protease of 202 kda. we inves ... | 2015 | 25175558 |
| surface modification of zirconia with polydopamine to enhance fibroblast response and decrease bacterial activity in vitro: a potential technique for soft tissue engineering applications. | the quality of soft-tissue integration plays an important role in the short- and long-term success of dental implants. the aim of the present study was to provide a surface modification approach for zirconia implant abutment materials and to evaluate its influence on fibroblast behavior and oral bacteria adhesion, which are the two main factors influencing the quality of peri-implant soft-tissue seal. in this study, polydopamine (pda)-coated zirconia was prepared and the surface characteristics ... | 2015 | 26363269 |
| structural and dynamical aspects of streptococcus gordonii fabh through molecular docking and md simulations. | β-ketoacyl-acp-synthase iii (fabh or kas iii) has become an attractive target for the development of new antibacterial agents which can overcome the multidrug resistance. unraveling the fatty acid biosynthesis (fab) metabolic pathway and understanding structural coordinates of fabh will provide valuable insights to target streptococcus gordonii for curing oral infection. in this study, we designed inhibitors against therapeutic target fabh, in order to block the fab pathway. as compared to other ... | 2015 | 26059477 |
| dynamics of the streptococcus gordonii transcriptome in response to medium, salivary α-amylase, and starch. | streptococcus gordonii, a primary colonizer of the tooth surface, interacts with salivary α-amylase via amylase-binding protein a (abpa). this enzyme hydrolyzes starch to glucose, maltose, and maltodextrins that can be utilized by various oral bacteria for nutrition. microarray studies demonstrated that abpa modulates gene expression in response to amylase, suggesting that the amylase-streptococcal interaction may function in ways other than nutrition. the goal of this study was to explore the r ... | 2015 | 26025889 |
| the sialic acid binding protein, hsa, in streptococcus gordonii dl1 also mediates intergeneric coaggregation with veillonella species. | dental biofilm development involves initial colonization of the tooth's surface by pioneer colonizers, followed by cell-cell coaggregation between the pioneer and later colonizers. streptococcus gordonii is one of the pioneer colonizers. in addition to its role in oral biofilm development, s. gordonii also is a pathogen in infective endocarditis in susceptible humans. a surface adhesin, hsa, has been shown to play a critical role in colonization of s. gordonii on the heart tissue; however, its r ... | 2015 | 26606595 |
| mutation of the thiol-disulfide oxidoreductase sdba activates the ciarh two-component system, leading to bacteriocin expression shutdown in streptococcus gordonii. | streptococcus gordonii is a commensal inhabitant of the human oral cavity. to maintain its presence as a major component of oral biofilms, s. gordonii secretes inhibitory molecules such as hydrogen peroxide and bacteriocins to inhibit competitors. s. gordonii produces two nonmodified bacteriocins (i.e., sth1 and sth2) that are regulated by the com two-component regulatory system, which also regulates genetic competence. previously we found that the thiol-disulfide oxidoreductase sdba was require ... | 2015 | 26527641 |
| characterization of high-level daptomycin resistance in viridans group streptococci developed upon in vitro exposure to daptomycin. | viridans group streptococci (vgs) are part of the normal flora that may cause bacteremia, often leading to endocarditis. we evaluated daptomycin against four clinical strains of vgs (mics = 1 or 2 μg/ml) using an in vitro-simulated endocardial vegetation model, a simulated bacteremia model, and kill curves. daptomycin exposure was simulated at 6 mg/kg of body weight and 8 mg/kg every 24 h for endocardial and bacteremia models. total drug concentrations were used for analyses containing protein ( ... | 2015 | 25624330 |
| streptococcus gordonii prosthetic joint infection in the setting of vigorous dental flossing. | a 65-year-old woman with osteoarthritis, who underwent knee replacement 5 years prior, developed sudden onset knee pain and swelling. she had voluntarily starting a vigorous dental flossing regimen prior to the onset of symptoms. the patient underwent right knee arthrotomy, irrigation and debridement of right total knee arthroplasty and exchange of polyethylene with retention of the prosthesis. intraoperative cultures grew streptococcus gordonii. she was treated with 6 weeks of ceftriaxone and w ... | 2015 | 26264944 |
| conserved and divergent functions of rcrrpq in streptococcus gordonii and s. mutans. | in the dental caries pathogen streptococcus mutans, an marr-like transcriptional regulator (rcrr), two abc efflux pumps (rcrpq) and two effector peptides encoded in the rcrrpq operon provide molecular connections between stress tolerance, (p)ppgpp metabolism and genetic competence. here, we examined the role of rcrrpq in the oral commensal s. gordonii. unlike in s. mutans, introduction of polar or non-polar rcrr mutations into s. gordonii elicited no significant changes in transformation efficie ... | 2015 | 26229070 |
| chlorhexidine uptake and release from modified titanium surfaces and its antimicrobial activity. | decontamination by adjunctive antiseptic agents such as chlorhexidine (chx) is often recommended for the treatment of peri-implant infections. however, its action on the titanium implant surface needs further research. this study is designed to evaluate the ability of modified titanium surfaces to release chlorhexidine after periodic chx exposure. | 2015 | 26156675 |
| chlorhexidine hexametaphosphate nanoparticles as a novel antimicrobial coating for dental implants. | dental implants are an increasingly popular solution to missing teeth. implants are prone to colonisation by pathogenic oral bacteria which can lead to inflammation, destruction of bone and ultimately implant failure. the aim of this study was to investigate the use of chlorhexidine (chx) hexametaphosphate (hmp) nanoparticles (nps) with a total chx concentration equivalent to 5 mm as a coating for dental implants. the chx hmp nps had mean diameter 49 nm and composition was confirmed showing pres ... | 2015 | 26123234 |
| association of oral streptococci community dynamics with severe early childhood caries as assessed by pcr-denaturing gradient gel electrophoresis targeting the rnpb gene. | this study sought to investigate the possible association between the dynamics of oral streptococci community profiles and severe early childhood caries (s-ecc) development, compared with caries-free (cf) controls. supragingival plaque samples were evaluated from 8-32-month-old children who had previously been assessed for overall profiles of their oral microbial community. twelve children were in each group. bacterial genomic dna was extracted and amplified using rnpb-specific primers for strep ... | 2015 | 26002941 |
| the interaction between streptococcus spp. and veillonella tobetsuensis in the early stages of oral biofilm formation. | dental plaque is a multispecies oral biofilm, the development of which is initiated by adherence of the pioneer streptococcus spp. oral veillonella spp., including v. atypica, v. denticariosi, v. dispar, v. parvula, v. rogosae, and v. tobetsuensis, are known as early colonizers in oral biofilm formation. these species have been reported to co-aggregate with streptococcus spp. in a metabolic cooperation-dependent manner to form biofilms in human oral cavities, especially in the early stages of bi ... | 2015 | 25917902 |
| [effects of growth stages and ph value on the expression of autolytic enzyme atis gene of streptococcus gordonii]. | this study aimed to detect the difference in the expression levels of autolysin atis gene of streptococcus gordonii (s. gordonii) at different growth stages and ph values, as well as to analyze the factors regulating atls gene expression in s. gordonii. | 2015 | 25872305 |
| biological activation of zirconia surfaces by chemical modification with igf-1. | the purpose of this study was to improve the adhesion and extension of human gingival epithelial cells (hgecs) to the yttria-stabilized zirconia polycrystal (y-tzp) surfaces by immobilization of insulin-like growth factor 1 (igf-1). surface analyses by fourier transform infrared spectroscopy (ftir) and x-ray photoelectron spectroscopy (xps) showed that igf-1 was successfully immobilized on the y-tzp surfaces. there was no significant difference between the number of cells attached to the igf-1-i ... | 2015 | 25845378 |
| structure of amylase-binding protein a of streptococcus gordonii: a potential receptor for human salivary α-amylase enzyme. | amylase-binding protein a (abpa) of a number of oral streptococci is essential for the colonization of the dental pellicle. we have determined the solution structure of residues 24-195 of abpa of streptococcus gordonii and show a well-defined core of five helices in the region of 45-115 and 135-145. (13) cα/β chemical shift and heteronuclear (15) n-{(1) h} noe data are consistent with this fold and that the remainder of the protein is unstructured. the structure will inform future molecular expe ... | 2015 | 25739638 |
| effect of antibacterial dental adhesive on multispecies biofilms formation. | antibacterial adhesives have favorable prospects to inhibit biofilms and secondary caries. the objectives of this study were to investigate the antibacterial effect of dental adhesives containing dimethylaminododecyl methacrylate (dmaddm) on different bacteria in controlled multispecies biofilms and its regulating effect on development of biofilm for the first time. antibacterial material was synthesized, and streptococcus mutans, streptococcus gordonii, and streptococcus sanguinis were chosen t ... | 2015 | 25715378 |
| high-resolution analyses of overlap in the microbiota between mothers and their children. | understanding the transmission of the human microbiota from mother to child is of major importance. although we are gaining knowledge using 16s rrna gene analyses, the resolution of this gene is not sufficient to determine transmission patterns. we therefore developed an illumina deep sequencing approach targeting the 16-23s rrna internal transcribed spacer (its) for high-resolution microbiota analyses. using this approach, we analyzed the composition and potential mother to child transmission p ... | 2015 | 26044992 |
| antibacterial activity of berry juices, an in vitro study. | the aim of the present study was to evaluate in vitro antibacterial activities of blackcurrant and sea buckthorn juices on bacteria associated with gingival inflammation. | 2015 | 25727734 |
| prophylaxis of experimental endocarditis with antiplatelet and antithrombin agents: a role for long-term prevention of infective endocarditis in humans? | infective endocarditis (ie) mostly occurs after spontaneous low-grade bacteremia. thus, ie cannot be prevented by circumstantial antibiotic prophylaxis. platelet activation following bacterial-fibrinogen interaction or thrombin-mediated fibrinogen-fibrin polymerization is a critical step in vegetation formation. we tested the efficacy of antiplatelet and antithrombin to prevent experimental ie. | 2015 | 25086177 |
| antigen i/ii encoded by integrative and conjugative elements of streptococcus agalactiae and role in biofilm formation. | streptococcus agalactiae (i.e. group b streptococcus, gbs) is a major human and animal pathogen. genes encoding putative surface proteins and in particular an antigen i/ii have been identified on integrative and conjugative elements (ices) found in gbs. antigens i/ii are multimodal adhesins promoting colonization of the oral cavity by streptococci such as streptococcus gordonii and streptococcus mutans. the prevalence and diversity of antigens i/ii in gbs were studied by a bioinformatic analysis ... | 2015 | 26232503 |
| group b streptococcal infection and activation of human astrocytes. | streptococcus agalactiae (group b streptococcus, gbs) is the leading cause of life-threatening meningitis in human newborns in industrialized countries. meningitis results from neonatal infection that occurs when gbs leaves the bloodstream (bacteremia), crosses the blood-brain barrier (bbb), and enters the central nervous system (cns), where the bacteria contact the meninges. although gbs is known to invade the bbb, subsequent interaction with astrocytes that physically associate with brain endo ... | 2015 | 26030618 |
| efficacy of a novel antimicrobial peptide against periodontal pathogens in both planktonic and polymicrobial biofilm states. | streptococcus gordonii, fusobacterium nucleatum and porphyromonas gingivalis represent the early, middle and late colonizers of the bacterial accretion in dental plaque biofilms. these sessile communities constitute a protected mode of growth that promotes survival in a hostile environment. this study describes a novel and unrecognized role for a synthetic cationic antimicrobial peptide, nal-p-113, which inhibits and kills periodontal bacteria in planktonic state, inhibits the formation of biofi ... | 2015 | 26210284 |
| alcohol metabolism by oral streptococci and interaction with human papillomavirus leads to malignant transformation of oral keratinocytes. | poor oral hygiene, ethanol consumption, and human papillomavirus (hpv) are associated with oral and esophageal cancers. however, the mechanism is not fully known. this study examines alcohol metabolism in streptococcus and its interaction with hpv-16 in the malignant transformation of oral keratinocytes. the acetaldehyde-producing strain streptococcus gordonii v2016 was analyzed for adh genes and activities of alcohol and aldehyde dehydrogenases. streptococcus attachment to immortalized hpv-16 i ... | 2015 | 25427911 |
| comparison of species identification of endocarditis associated viridans streptococci using rnpb genotyping and 2 maldi-tof systems. | streptococcus spp. are important causes of infective endocarditis but challenging in species identification. this study compared identification based on sequence determination of the rnpb gene with 2 systems of matrix-assisted laser desorption ionization-time of flight mass spectrometry, maldi biotyper (bruker) and vitek ms ivd (biomérieux). blood culture isolates of viridans streptococci from 63 patients with infective endocarditis were tested. the 3 methods showed full agreement for all 36 iso ... | 2015 | 25616316 |
| electrical enhancement of chlorhexidine efficacy against the periodontal pathogen porphyromonas gingivalis within a biofilm. | electric currents have been shown to promote the antimicrobial effectiveness of several biocides against microbial biofilms. therefore, the objective of this work was to test the null hypothesis that low electric direct currents (dc) do not influence chlorhexidine (chx) efficacy against the periodontal pathogen porphyromonas gingivalis within a biofilm. a brain heart infusion medium inoculated with streptococcus gordonii and p. gingivalis was perfused for 7 days in anaerobiosis through two modif ... | 2015 | 26571378 |
| evaluation of the co-existence of the red fluorescent plaque bacteria p. gingivalis with s. gordonii and s. mutans in white spot lesion formation during orthodontic treatment. | early detection of white spot lesions (wsls) around brackets during orthodontic treatment is important for treatment and prevention. but it is unclear whether red fluorescent plaque (rfp) bacteria porphyromonas gingivalis and its co-existence with streptococcus mutans and streptococcus gordonii has any significant influence on this. therefore the role of this bacterial co existence and wsls formation during one year of fixed orthodontic therapy was evaluated. | 2015 | 25813147 |
| functional regions of candida albicans hyphal cell wall protein als3 that determine interaction with the oral bacterium streptococcus gordonii. | the opportunistic pathogen candida albicans colonizes the oral cavity and gastrointestinal tract. adherence to host cells, extracellular matrix and salivary glycoproteins that coat oral surfaces, including prostheses, is an important prerequisite for colonization. in addition, interactions of c. albicans with commensal oral streptococci are suggested to promote retention and persistence of fungal cells in mixed-species communities. the hyphal filament specific cell wall protein als3, a member of ... | 2015 | 25332379 |
| functional advantages of porphyromonas gingivalis vesicles. | porphyromonas gingivalis is a keystone pathogen of periodontitis. outer membrane vesicles (omvs) have been considered as both offense and defense components of this bacterium. previous studies indicated that like their originating cells, p. gingivalis vesicles, are able to invade oral epithelial cells and gingival fibroblasts, in order to promote aggregation of some specific oral bacteria and to induce host immune responses. in the present study, we investigated the invasive efficiency of p. gin ... | 2015 | 25897780 |
| arginine-ornithine antiporter arcd controls arginine metabolism and interspecies biofilm development of streptococcus gordonii. | arginine is utilized by the oral inhabitant streptococcus gordonii as a substrate of the arginine deiminase system (ads), eventually producing atp and nh3, the latter of which is responsible for microbial resistance to ph stress. s. gordonii expresses a putative arginine-ornithine antiporter (arcd) whose function has not been investigated despite relevance to the ads and potential influence on inter-bacterial communication with periodontal pathogens that utilize amino acids as a main energy sour ... | 2015 | 26085091 |
| streptococcus gordonii dl1 adhesin sspb v-region mediates coaggregation via receptor polysaccharide of actinomyces oris t14v. | streptococcus gordonii sspa and sspb proteins, members of the antigen i/ii (agi/ii) family of streptococcus adhesins, mediate adherence to cysteine-rich scavenger glycoprotein gp340 and cells of other oral microbial species. in this article we investigated further the mechanism of coaggregation between s. gordonii dl1 and actinomyces oris t14v. previous mutational analysis of s. gordonii suggested that sspb was necessary for coaggregation with a. oris t14v. we have confirmed this by showing that ... | 2015 | 25965671 |
| critical roles of arginine in growth and biofilm development by streptococcus gordonii. | streptococcus gordonii is an oral commensal and an early coloniser of dental plaque. in vitro, s. gordonii is conditionally auxotrophic for arginine in monoculture but biosynthesises arginine when coaggregated with actinomyces oris. here, we investigated the arginine-responsive regulatory network of s. gordonii and the basis for conditional arginine auxotrophy. arcb, the catabolic ornithine carbamoyltransferase involved in arginine degradation, was also essential for arginine biosynthesis. howev ... | 2015 | 25855127 |
| bacteria-induced intracellular signalling in platelets. | multiple studies have now shown that various species of bacteria can stimulate platelets; many in a strain and donor-dependent manner. the signalling pathways underlying this platelet activation has been the subject of scrutiny for the last decade. the best-delineated pathway is that in response to streptococcal species, such as streptococcus sanguinis (s. sanguinis), streptococcus gordonii (s. gordonii) and streptococcus oralis (s. oralis), where a pathway is initiated by the engagement of the ... | 2015 | 25807064 |
| codon-optimized fluorescent mtfp and mcherry for microscopic visualization and genetic counterselection of streptococci and enterococci. | despite the powerful potential of fluorescent proteins for labeling bacteria, their use has been limited in multi-species oral biofilm models. fermentative metabolism by streptococcal species that initiate biofilm colonization results in an acidic, reduced microenvironment that may limit the activities of some fluorescent proteins which are influenced by ph and oxygen availability. the need to reliably distinguish morphologically similar strains within biofilms was the impetus for this work. tea ... | 2015 | 26122309 |
| environment and colonisation sequence are key parameters driving cooperation and competition between pseudomonas aeruginosa cystic fibrosis strains and oral commensal streptococci. | cystic fibrosis (cf) patient airways harbour diverse microbial consortia that, in addition to the recognized principal pathogen pseudomonas aeruginosa, include other bacteria commonly regarded as commensals. the latter include the oral (viridans) streptococci, which recent evidence indicates play an active role during infection of this environmentally diverse niche. as the interactions between inhabitants of the cf airway can potentially alter disease progression, it is important to identify key ... | 2015 | 25710466 |
| oral streptococci and nitrite-mediated interference of pseudomonas aeruginosa. | the oral cavity harbors a diverse community of microbes that are physiologically unique. oral microbes that exist in this polymicrobial environment can be pathogenic or beneficial to the host. numerous oral microbes contribute to the formation of dental caries and periodontitis; however, there is little understanding of the role these microbes play in systemic infections. there is mounting evidence that suggests that oral commensal streptococci are cocolonized with pseudomonas aeruginosa during ... | 2015 | 25312949 |
| streptococcus gordonii comcde (competence) operon modulates biofilm formation with candida albicans. | candida albicans is a pleiomorphic fungus that forms mixed species biofilms with streptococcus gordonii, an early colonizer of oral cavity surfaces. activation of quorum sensing (qs; intercellular signalling) promotes monospecies biofilm development by these micro-organisms, but the role of qs in mixed species communities is not understood. the comcde genes in s. gordonii encode a sensor-regulator system (comde), which is activated by the comc gene product (csp, competence stimulating peptide) a ... | 2015 | 25505189 |
| antimicrobial effect of lactobacillus reuteri on cariogenic bacteria streptococcus gordonii, streptococcus mutans, and periodontal diseases actinomyces naeslundii and tannerella forsythia. | lactic acid bacteria (lab) are well known for their beneficial effects on human health in the intestine and immune system; however, there are few studies on the impact they can generate in oral health. the aim of this study was to test and compare in vitro antimicrobial activity of l. reuteri on pathogenic bacteria involved in the formation of dental caries: s. mutans, s. gordonii, and periodontal disease: a. naeslundii and t. forsythia. also, we determined the growth kinetics of each bacterium ... | 2015 | 25422124 |
| biofilm formation on the surface of modern implant abutment materials. | to investigate the formation of biofilms on the surface of materials applied for the fabrication of implant abutments. | 2015 | 25060652 |
| strains of enterococcus faecalis differ in their ability to coexist in biofilms with other root canal bacteria. | to investigate the relationship between protease production and the ability of enterococcus faecalis strains to coexist in biofilms with other bacteria commonly recovered from infected root canals. | 2015 | 26172346 |
| impact of acquired pellicle modification on adhesion of early colonizers. | new preventive approaches against dental erosion caused by acidic drinks and beverages include fortification of beverages with natural polymers. we have shown that the mixture of casein and mucin significantly improved the erosion-inhibiting properties of the human pellicle layer. this study aimed to investigate the effect of pellicle modification by casein, mucin and a casein-mucin mixture on the adhesion of early bacterial colonizers. test specimens of human tooth enamel were prepared, covered ... | 2015 | 26655396 |
| a yada-like autotransporter, hag1 in veillonella atypica is a multivalent hemagglutinin involved in adherence to oral streptococci, porphyromonas gingivalis, and human oral buccal cells. | dental biofilm development is a sequential process, and adherence between microbes and the salivary pellicle (adhesion) as well as among different microbes (co-adhesion or coaggregation) plays a critical role in building a biofilm community. the veillonella species are among the most predominant species in the oral cavity and coaggregate with many initial, early, middle, and late colonizers. similar to oral fusobacteria, they are also considered bridging species in biofilm development. however, ... | 2015 | 25440509 |
| reduced glutathione mediates resistance to h2s toxicity in oral streptococci. | periodontal disease is associated with changes in the composition of the oral microflora, where health-associated oral streptococci decrease while gram-negative anaerobes predominate in disease. a key feature of periodontal disease-associated anaerobes is their ability to produce hydrogen sulfide (h2s) abundantly as a by-product of anaerobic metabolism. so far, h2s has been reported to be either cytoprotective or cytotoxic by modulating bacterial antioxidant defense systems. although oral anaero ... | 2016 | 26801579 |
| differential utilization of basic proline-rich glycoproteins during growth of oral bacteria in saliva. | although saliva is widely recognized as a primary source of carbon and nitrogen for growth of the dental plaque biofilm community, little is known about how different oral bacteria utilize specific salivary components. to address this question, 32 strains representing 16 genera commonly isolated from early plaque biofilms were compared for growth over two transfers in stimulated (by chewing parafilm) whole saliva that was stabilized by heat treatment and dialysis. the cell densities, measured by ... | 2016 | 27316966 |
| molecular detection of bacteria associated to caries activity in dentinal lesions. | this study aimed at identifying and quantifying actinomyces naeslundii, bifidobacterium spp., streptococcus mitis group, lactobacillus acidophilus, lactobacillus casei group, streptococcus gordonii, and streptococcus mutans in active and inactive carious dentine lesions of children with early childhood caries by using quantitative polymerase chain reaction. | 2016 | 27837345 |
| l-arginine modifies the exopolysaccharide matrix and thwarts streptococcus mutans outgrowth within mixed-species oral biofilms. | l-arginine, a ubiquitous amino acid in human saliva, serves as a substrate for alkali production by arginolytic bacteria. recently, exogenous l-arginine has been shown to enhance the alkalinogenic potential of oral biofilm and destabilize its microbial community, which might help control dental caries. however, l-arginine exposure may inflict additional changes in the biofilm milieu when bacteria are growing under cariogenic conditions. here, we investigated how exogenous l-arginine modulates bi ... | 2016 | 27161116 |
| comparison of human gut microbiota in control subjects and patients with colorectal carcinoma in adenoma: terminal restriction fragment length polymorphism and next-generation sequencing analyses. | colorectal cancer (crc) is the third leading cause of cancer-related deaths in japan. the etiology of crc has been linked to numerous factors including genetic mutation, diet, life style, inflammation, and recently, the gut microbiota. however, crc-associated gut microbiota is still largely unexamined. this study used terminal restriction fragment length polymorphism (t-rflp) and next-generation sequencing (ngs) to analyze and compare gut microbiota of japanese control subjects and japanese pati ... | 2016 | 26549775 |
| high-throughput quantitative method for assessing coaggregation among oral bacterial species. | this paper describes a high-throughput method that relies upon a microplate reader to score coaggregation 60 min postmixing, and use of a high-speed real-time imaging technology to describe the rate of coaggregation over time. the results of visual, microplate, and flowcam(™) aggregation scores for oral bacteria streptococcus gordonii, streptococcus oralis, and actinomyces oris, whose ability to coaggregate are well characterized, are compared. following mixing of all possible pairs, the top fra ... | 2016 | 27455031 |
| mutation of the streptococcus gordonii thiol-disulfide oxidoreductase sdba leads to enhanced biofilm formation mediated by the ciarh two-component signaling system. | streptococcus gordonii is a commensal inhabitant of human oral biofilms. previously, we identified an enzyme called sdba that played an important role in biofilm formation by s. gordonii. sdba is thiol-disulfide oxidoreductase that catalyzes disulfide bonds in secreted proteins. surprisingly, inactivation of sdba results in enhanced biofilm formation. in this study we investigated the basis for biofilm formation by the δsdba mutant. the results revealed that biofilm formation was mediated by the ... | 2016 | 27846284 |
| an in vitro model for oral mixed biofilms of candida albicans and streptococcus gordonii in synthetic saliva. | as a member of the normal human oral microbiota, the fungus candida albicans is often found in association with streptococcus gordonii, a member of dental plaque forming bacteria. evidence suggests that s. gordonii serves as a facilitator of c. albicans adherence to dental tissues, which represents a clinically relevant problem, particularly for immunocompromised individuals that could subsequently develop fungal infections. in this study we describe the development of a relatively simple and ec ... | 2016 | 27242712 |
| transcriptome analysis of streptococcus gordonii challis dl1 indicates a role for the biofilm-associated frurba operon in response to candida albicans. | multiple levels of interkingdom signaling have been implicated in maintaining the ecological balance between candida albicans and commensal streptococci to assure a state of oral health. to better understand the molecular mechanisms involved in the initial streptococcal response to the presence of c. albicans that can initiate oral surface colonization and biofilm formation, hypha-forming cells were incubated with streptococcus gordonii cells for 30 min to assess the streptococcal transcriptome ... | 2016 | 26280461 |
| transcriptional landscape of trans-kingdom communication between candida albicans and streptococcus gordonii. | recent studies have shown that the transcriptional landscape of the pleiomorphic fungus candida albicans is highly dependent upon growth conditions. here using a dual rna-seq approach we identified 299 c. albicans and 72 streptococcus gordonii genes that were either upregulated or downregulated specifically as a result of co-culturing these human oral cavity microorganisms. seventy-five c. albicans genes involved in responses to chemical stimuli, regulation, homeostasis, protein modification and ... | 2016 | 26042999 |
| antibodies targeting hsa and pada prevent platelet aggregation and protect rats against experimental endocarditis induced by streptococcus gordonii. | streptococcus gordonii and related species of oral viridans group streptococci (vgs) are common etiological agents of infective endocarditis (ie). we explored vaccination as a strategy to prevent vgs-ie, using a novel antigen-presenting system based on non-genetically modified lactococcus lactis displaying vaccinogens on its surface. hsa and pada are surface-located s. gordonii proteins implicated in platelet adhesion and aggregation, which are key steps in the pathogenesis of ie. this function ... | 2016 | 27736784 |
| in silico dissection of type vii secretion system components across bacteria: new directions towards functional characterization. | type vii secretion system (t7ss) is one of the factors involved in virulence of mycobacterium tuberculosis h37rv. numerous research efforts have been made in the last decade towards characterizing the components of this secretion system. an extensive genome-wide analysis through compilation of isolated information is required to obtain a global view of diverse characteristics and pathogenicity-related aspects of this machinery. the present study suggests that differences in structural components ... | 2016 | 26949095 |
| collagen-like peptide sequences inhibit bacterial invasion of root dentine. | to investigate the effects of peptides derived from the sequence of collagen to inhibit penetration of human or bovine dentine by species of streptococci and enterococci. | 2016 | 26011655 |
| composition and activity of the non-canonical gram-positive secy2 complex. | the accessory sec system in streptococcus gordonii dl1 is a specialized export system that transports a large serine-rich repeat protein, hsa, to the bacterial surface. the system is composed of core proteins seca2 and secy2 and accessory sec proteins asp1-asp5. similar to canonical secyeg, secy2 forms a channel for translocation of the hsa adhesin across the cytoplasmic membrane. accessory sec proteins asp4 and asp5 have been suggested to work alongside secy2 to form the translocon, similar to ... | 2016 | 27551046 |
| microbial community composition impacts pathogen iron availability during polymicrobial infection. | iron is an essential nutrient for bacterial pathogenesis, but in the host, iron is tightly sequestered, limiting its availability for bacterial growth. although this is an important arm of host immunity, most studies examine how bacteria respond to iron restriction in laboratory rather than host settings, where the microbiome can potentially alter pathogen strategies for acquiring iron. one of the most important transcriptional regulators controlling bacterial iron homeostasis is fur. here we us ... | 2016 | 27973608 |
| oxygen as a virulence determinant in polymicrobial infections. | infections caused by multiple organisms, or polymicrobial infections, are likely more common than is broadly appreciated. interaction among microbial communities (and with their host) can change the infection landscape by subverting immunity, providing nutrients and inhibiting competing microbes. stacy et al. (a. stacy, d. fleming, r. j. lamont, k. p. rumbaugh, and m. whiteley, mbio 7:e00782-16, 2016, http://dx.doi.org/10.1128/mbio.00782-16) described a novel mechanism that results in synergisti ... | 2016 | 27531913 |
| a commensal bacterium promotes virulence of an opportunistic pathogen via cross-respiration. | bacteria rarely inhabit infection sites alone, instead residing in diverse, multispecies communities. despite this fact, bacterial pathogenesis studies primarily focus on monoculture infections, overlooking how community interactions influence the course of disease. in this study, we used global mutant fitness profiling (transposon sequencing [tn-seq]) to determine the genetic requirements for the pathogenic bacterium aggregatibacter actinomycetemcomitans to cause disease when coinfecting with t ... | 2016 | 27353758 |
| bacterial invasion into radicular dentine-an in vitro study. | we wanted to investigate differences in invasiveness into radicular dentinal tubules by monocultured and co-cultured bacteria frequently found in infected root canals. | 2016 | 27722787 |
| the starvation resistance and biofilm formation of enterococcus faecalis in coexistence with candida albicans, streptococcus gordonii, actinomyces viscosus, or lactobacillus acidophilus. | enterococcus faecalis is the most frequently detected species in root canal-treated teeth, and it is able to survive under starvation conditions. however, persistent periapical disease is often caused by multispecies. the aim of this study was to explore the survival of e. faecalis in starvation conditions and biofilm formation with the 4 common pathogenic species. | 2016 | 27316318 |
| antimicrobial effects of commensal oral species are regulated by environmental factors. | the objectives of this study are to identify oral commensal species which can inhibit the growth of the main periodontopathogens, to determine the antimicrobial substances involved in these inhibitory activities and to evaluate the influence of environmental factors on the magnitude of these inhibitions. | 2016 | 26875613 |
| antibacterial activity of curcumin against periodontopathic bacteria. | curcumin is a polyphenol extracted from root of turmeric and known to possess multifunctional properties, including antibacterial activity. although previous studies have investigated the effects of curcumin on microorganisms, available knowledge on the effects of curcumin on periodontopathic bacteria is still limited. in this study, the antibacterial effect of curcumin on periodontopathic bacteria is investigated, particularly porphyromonas gingivalis. | 2016 | 26447754 |
| role of candida albicans secreted aspartyl protease sap9 in interkingdom biofilm formation. | the fungus candida albicans colonizes oral cavity surfaces and is carried by up to 60% of human populations. biofilm development by c. albicans may be modulated by oral streptococci, such as streptococcus gordonii, s. oralis or s. mutans, so as to augment pathogenicity. in this study we sought to determine if the cell wall-associated secreted aspartyl proteinase sap9 was necessary for hyphal adhesin functions associated with biofilm community development. a sap9δ mutant of c. albicans sc5314 for ... | 2016 | 26772652 |
| effects of surface reaction-type pre-reacted glass ionomer on oral biofilm formation of streptococcus gordonii. | streptococcus gordonii, a bacterium involved in the initial colonization of tooth surfaces, contributes to dental biofilm formation and is an important cause of infective endocarditis. this study aimed to investigate the influence of surface reaction-type pre-reacted glass ionomer (s-prg) filler on oral bacterial growth and aggregation of s. gordonii. the effect of various concentrations of s-prg eluate on the growth and the biofilm formation of s. gordonii and other oral microorganisms (strepto ... | 2016 | 26319990 |
| development of a gene delivery system in streptococcus gordonii using thymidylate synthase as a selection marker. | streptococcus gordonii, a commensal bacterium of the human oral cavity, is a potential live vaccine vector. in this study, we have developed a system that delivers a vaccine antigen gene onto the chromosome of s. gordonii. the system consisted of a recipient strain, that is a thymidine auxotroph constructed by deletion of a portion of thya gene, and a linear gene delivery construct, composed of the functional thya gene, the vaccine antigen gene, and a dna fragment immediately downstream of thya. ... | 2016 | 27062990 |
| correction: two arginine residues of streptococcus gordonii sialic acid-binding adhesin hsa are essential for interaction to host cell receptors. | [this corrects the article doi: 10.1371/journal.pone.0154098.]. | 2016 | 27548255 |
| contribution of streptococcus gordonii hsa adhesin to biofilm formation. | adhesion of oral mitis group streptococci such as streptococcus gordonii to acquired pellicle of the tooth surface is the initial step of oral biofilm formation. s. gordonii wild type strain dl1 possesses hsa adhesin, recognizing terminal sialic acid of the host sialoglycoconjugates. the aim of the present study was to investigate the role of hsa adhesin in biofilm formation. biofilm-forming ability of the s. gordonii hsa mutant in microtiter plates pre-coated with saliva, fetuin and mucin was s ... | 2016 | 28003605 |
| structure-function aspects of the porphyromonas gingivalis tyrosine kinase ptk1. | the development of synergistically pathogenic communities of porphyromonas gingivalis and streptococcus gordonii is controlled by a tyrosine-phosphorylation-dependent signaling pathway in p. gingivalis. the ptk1 bacterial tyrosine (by) kinase of p. gingivalis is required for maximal community development and for the production of extracellular polysaccharide. we show that the consensus by kinase walker a and b domains, the rk cluster, and the yc domain of ptk1 are necessary for autophosphorylati ... | 2016 | 27498608 |
| autoinducer-2 detection among commensal oral streptococci is dependent on ph and boric acid. | autoinducer-2, considered a universal signaling molecule, is produced by many species of bacteria; including oral strains. structurally, autoinducer-2 can exist bound to boron (borated autoinducer-2). functionally, autoinducer-2 has been linked to important bacterial processes such as virulence and biofilm formation. in order to test production of autoinducer-2 by a given bacterial strain, a bioassay using marine bioluminescent bacteria vibrio harveyi as a reporter for autoinducer-2 has been des ... | 2016 | 27350615 |
| cell surface glycoside hydrolases of streptococcus gordonii promote growth in saliva. | the growth of the oral commensal streptococcus gordonii in saliva may depend on a number of glycoside hydrolases (ghs), including three cell wall-anchored proteins that are homologs of pneumococcal β-galactosidase (bgaa), β-n-acetylglucosaminidase (strh), and endo-β-n-acetylglucosaminidase d (endod). in the present study, we introduced unmarked in-frame deletions into the corresponding genes of s. gordonii dl1, verified the presence (or absence) of the encoded proteins on the resulting mutant st ... | 2016 | 27316967 |
| 1,2,3-triazole-based inhibitors of porphyromonas gingivalis adherence to oral streptococci and biofilm formation. | the development and use of small-molecule inhibitors of the adherence of porphyromonas gingivalis to oral streptococci represents a potential therapy for the treatment of periodontal disease as these organisms work in tandem to colonize the oral cavity. earlier work from these laboratories demonstrated that a small synthetic peptide was an effective inhibitor of the interaction between p. gingivalis and streptococcus gordonii and that a small-molecule peptidomimetic would provide a more stable, ... | 2016 | 27647373 |
| porphyromonas gingivalis initiates a mesenchymal-like transition through zeb1 in gingival epithelial cells. | the oral anaerobe porphyromonas gingivalis is associated with the development of cancers including oral squamous cell carcinoma (oscc). here, we show that infection of gingival epithelial cells with p. gingivalis induces expression and nuclear localization of the zeb1 transcription factor, which controls epithelial-mesenchymal transition. p. gingivalis also caused an increase in zeb1 expression as a dual species community with fusobacterium nucleatum or streptococcus gordonii. increased zeb1 exp ... | 2016 | 26639759 |
| a highly arginolytic streptococcus species that potently antagonizes streptococcus mutans. | the ability of certain oral biofilm bacteria to moderate ph through arginine metabolism by the arginine deiminase system (ads) is a deterrent to the development of dental caries. here, we characterize a novel streptococcus strain, designated strain a12, isolated from supragingival dental plaque of a caries-free individual. a12 not only expressed the ads pathway at high levels under a variety of conditions but also effectively inhibited growth and two intercellular signaling pathways of the denta ... | 2016 | 26826230 |
| pronounced heterogeneity observed in high-level daptomycin-resistant viridans group streptococci. | viridans group streptococci (vgs) have demonstrated high-level daptomycin resistance (hldr) upon daptomycin exposure. this study evaluated the extent of heterogeneity and whether dose escalation or combination therapy could prevent resistance development. five vgs strains (daptomycin mics 0.25-2mg/l) were evaluated. in vitro models utilised simulated daptomycin dosages of 4, 6, 8 and 12mg/kg with estimated fcmax of 4.1, 6.6, 8.6 and 12.9mg/l, respectively. time-kill studies included fcmax simula ... | 2016 | 27835845 |
| design, synthesis and biological evaluation of potential antibacterial butyrolactones. | novel butyrolactone analogues were designed and synthesized based on the known lichen antibacterial compounds, lichesterinic acids (b-10 and b-11), by substituting different functional groups on the butyrolactone ring trying to enhance its activity. all synthesized butyrolactone analogues were evaluated for their in vitro antibacterial activity against streptococcus gordonii. among the derivatives, b-12 and b-13 had the lowest mic of 9.38μg/ml where they have shown to be stronger bactericidals, ... | 2016 | 27687969 |