| restriction endonuclease-fragment polymorphisms of oral viridans streptococci, compared by conventional and field-inversion gel electrophoresis. | oral streptococci formerly classified as streptococcus sanguis or streptococcus mitis have recently been divided into four species. two additional species have also been proposed for this group. each species is genetically distinct, but they have many traits in common, which makes it difficult for clinical isolates to be identified by phenotypic tests. genotypic comparison may provide an alternative approach. this study used dna fingerprint analysis for comparison of genotypes of 21 reference st ... | 1992 | 1351484 |
| streptococcus parasanguis sp. nov., an atypical viridans streptococcus from human clinical specimens. | molecular taxonomic studies were performed on ten strains of an unusual 'viridans streptococcus' that were originally isolated from human throats, blood and urine. on the basis of dna-dna hybridization studies the strains formed a single homology group distinct from all recognized species of oral and viridans streptococci. 16s ribosomal rna reverse transcriptase sequence studies confirmed the genealogical distinctiveness of the human strains. the results of the present study clearly demonstrate ... | 1990 | 1692001 |
| use of restriction fragment polymorphism analysis of rrna genes to assign species to unknown clinical isolates of oral viridans streptococci. | this study evaluated restriction fragment length polymorphisms of rrna genes (ribotyping) for genotypic identification of 53 oral isolates classified as "streptococcus sanguis" by colony morphology. isolates were from 8-h buccal plaque on lower first permanent molars of 20 subjects. dna was digested with aatii and hybridized with digoxygenin-labeled cdna of escherichia coli 16s and 23s rrna. strains were ribotyped again with alwni or pvuii on the basis of the presence or absence of a 2,290-bp aa ... | 1994 | 7512095 |
| determination of 16s rrna sequences of streptococcus mitis and streptococcus gordonii and phylogenetic relationships among members of the genus streptococcus. | we determined the 16s rrna sequences of the type strains of streptococcus mitis and streptococcus gordonii and calculated the phylogenetic distances between those organisms and other members of the genus streptococcus. the viridans group streptococci were separated into five phylogenetic groups; we named these groups the anginosus group, the mitis group, the salivarius group, the bovis group, and the mutans group. s. mitis and s. gordonii clustered in the mitis group together with streptococcus ... | 1995 | 7537076 |
| fima, a major virulence factor associated with streptococcus parasanguis endocarditis. | adherence of microorganisms to damaged heart tissue is a crucial event in the pathogenesis of infective endocarditis. in the present study, we investigated the role of the fima protein as a potential virulence factor associated with streptococcus parasanguis endocarditis. fima is a 36-kda surface protein that is a recognized adhesin in the oral cavity where it mediates adherence to the salivary pellicle. an insertion mutant and a deletion mutant of s. parasanguis were employed in the rat model o ... | 1995 | 7591121 |
| the fima locus of streptococcus parasanguis encodes an atp-binding membrane transport system. | the gene encoding fima, a 36 kda fimbrial adhesion of streptococcus parasanguis fw213, is highly conserved in all four genetic groups of sanguis streptococci. fima-like peptides were produced by all strains tested. the nucleotide sequence directly upstream of fima contains two open reading frames, orf5 and orf1, whose deduced protein products are homologous to members of a superfamily of atp-binding cassette membrane transport proteins, including both prokaryotic and eukaryotic uptake and export ... | 1995 | 7596287 |
| intrafamilial similarity in immunoblot profiles of salivary immunoglobulin a antibody activity to oral streptococci. | analysis of the salivary immunoglobulin a (iga) antibody activity to antigens separated from oral streptococci was carried out on 49 individuals in 11 families. the aim of this study were to i) study the human salivary iga activity within families to antigens separated from reference strains of streptococcus mutans, streptococcus sobrinus and streptococcus parasanguis and ii) to search for potential differences in the salivary iga activity to the streptococcal antigens several years apart. the i ... | 1995 | 7644270 |
| characteristics of actinobacillus actinomycetemcomitans invasion of and adhesion to cultured epithelial cells. | actinobacillus actinomycetemcomitans (a.a.) is highly implicated in periodontitis. we have developed several in vitro models using the kb oral cell line to examine a.a.-epithelial cell interactions. in support of the use of kb cell line model systems is our finding that a.a. invaded kb and primary gingival cells to the same extent. invasion is an active event which requires new protein synthesis by both kb and a.a. like many other intracellular parasites, a.a. invade by receptor-mediated endocyt ... | 1995 | 7669215 |
| cloning of an enterococcus faecalis endocarditis antigen: homology with adhesins from some oral streptococci. | serum from a patient with enterococcus faecalis endocarditis was used to identify the gene efaa cloned in lambda zapii in escherichia coli. nucleotide sequence analysis revealed a 924-bp open reading frame encoding a protein with a predicted molecular weight of 34,768. the amino acid sequence of efaa shows 55 to 60% homology to a group of streptococcal proteins, fima from streptococcus parasanguis, ssab from streptococcus sanguis, scaa from streptococcus gordonii, and psaa from streptococcus pne ... | 1995 | 7822045 |
| nucleotide sequence of the streptococcus gordonii pk488 coaggregation adhesin gene, scaa, and atp-binding cassette. | human oral viridans group streptococci that coaggregate with actinomyces naeslundii pk606 express surface proteins related to scaa, the coaggregation-mediating adhesin of streptococcus gordonii pk488 (r. n. andersen, n. ganeshkumar, and p. e. kolenbrander, infect. immun. 61:981-987, 1993). the nucleotide sequence of the 6,125-bp ecori insert of pra1, containing scaa, the gene encoding scaa, was determined. six open reading frames (orfs) were identified. the orientation of four orfs, two upstream ... | 1994 | 7927711 |
| detection of streptococcus pneumoniae dna in blood cultures by pcr. | we have developed a pcr assay, with primers derived from the autolysin (lyt) gene, for the detection of streptococcus pneumoniae dna in blood cultures. the predicted fragment of 247 bp was detected in all strains of pneumococci, embracing 12 different serotypes that were tested. although dna extracted from four viridans streptococci spp. streptococcus oralis, streptococcus mitis, streptococcus sanguis, and streptococcus parasanguis) gave amplification products, these were quite different from th ... | 1994 | 7929764 |
| overexpression and purification of a fimbria-associated adhesin of streptococcus parasanguis. | a streptococcus parasanguis adhesin that blocks the attachment of s. parasanguis fw213 to saliva-coated hydroxyapatite (scha) has been purified. previous work demonstrated that the attachment of fw213 to scha is mediated by fimbriae and that one component associated with fimbriae is a 36-kda protein (fima) that reacts with antifimbria serum in western blots (immunoblots) and is not present in afimbriated mutants. to obtain amounts of fima sufficient for adhesion blocking assays, we cloned the ge ... | 1993 | 8094376 |
| characterization of allelic replacement in streptococcus parasanguis: transformation and homologous recombination in a 'nontransformable' streptococcus. | we have obtained transformants of streptococcus parasanguis fw213 containing allelic replacements in several chromosomal loci. transformation occurred following electroporation with nonreplicating plasmids carrying two antibiotic-resistance-encoding genes, one of which is inserted into dna homologous to the chromosomal target. in contrast with other streptococci, s. parasanguis fw213 is not transformed by linear dna. mutations in nonreplicating plasmid dna preferentially replaced their homologue ... | 1993 | 8344531 |
| immunization with fima protects against streptococcus parasanguis endocarditis in rats. | fima, a surface-associated protein of streptococcus parasanguis, is associated with initial colonization of damaged heart tissue in an endocarditis model (d. burnette-curley, v. wells, h. viscount, c. munro, j. fenno, p. fives-taylor, and f. macrina, infect. immun. 63:4669-4674, 1995). we have evaluated the efficacy of recombinant fima as a vaccine in the rat model of endocarditis and investigated in vitro the mechanism for the protective role of immunization. fima-immunized and nonimmunized con ... | 1997 | 9038308 |
| 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 |
| competence and virulence of streptococcus pneumoniae: adc and psaa mutants exhibit a requirement for zn and mn resulting from inactivation of putative abc metal permeases. | the adccba putative operon of streptococcus pneumoniae, an important human pathogen, was identified in a search for transformation-deficient mutants. it was found to exhibit homology to atp-binding cassette (abc) transport operons encoding streptococcal adhesins such as fima of streptococcus parasanguis and psaa of s. pneumoniae. the latter was recently shown to be essential for virulence as judged by intranasal or intraperitoneal challenge of mice. we suggested previously that adca, together wi ... | 1997 | 9379902 |
| immunoglobulin a reaction to oral streptococci in saliva of subjects with different combinations of caries and levels of mutans streptococci. | the aim of this study, performed in bangkok, was to study whether a particular salivary immunoglobulin a (iga) antibody profile against mutans streptococci could be related to the absence or presence of caries. a group of 12-year-old individuals representing various combinations of mutans streptococci levels and caries experience was selected. whole saliva stimulated by paraffin-chewing was collected, and the children were investigated for decayed, missing and filled surfaces (dmfs) and teeth (d ... | 1997 | 9467389 |
| isolation and characterization of fap1, a fimbriae-associated adhesin of streptococcus parasanguis fw213. | an adhesin of streptococcus parasanguis fw213, a primary colonizer of the tooth surface, has been purified from the culture medium by immunoaffinity chromatography. the purified protein has a molecular mass of 200 kda and stains positively for carbohydrate. the amino-terminal sequence indicated that this protein represented a unique streptococcal surface protein. immunogold labelling of the bacterium indicated that this protein was associated with fimbriae and designated fap1 (fimbriae-associate ... | 1998 | 9632253 |
| expression of iron binding proteins and hemin binding activity in the dental pathogen actinobacillus actinomycetemcomitans. | actinobacillus actinomycetemcomitans was found to express a polypeptide immunologically related to the neisseria gonorrhoeae fbpa iron binding protein. in addition, the expression of hitb and hitc homologs was detected by northern blot analysis. this periodontal pathogen also expresses a polypeptide homologous to the 31-kda haemophilus influenzae protein, which shows amino acid sequence homology with the fima and yfea proteins from streptococcus parasanguis and yersinia pestis, respectively. bot ... | 1998 | 9673015 |
| molecular cloning of a 32-kilodalton lipoprotein component of a novel iron-regulated staphylococcus epidermidis abc transporter. | our previous studies identified two iron-regulated cytoplasmic membrane proteins of 32 and 36 kda expressed by both staphylococcus epidermidis and staphylococcus aureus. in this study we show by triton x-114 phase partitioning and tritiated palmitic acid labelling that these proteins are lipoproteins which are anchored into the cytoplasmic membrane by their lipid-modified n termini. in common with those of some other gram-positive bacteria, these highly immunogenic lipoproteins were released fro ... | 1998 | 9673260 |
| the expression and characterization of a putative adhesin b from h. influenzae. | in the h. influenzae type b (hib) genome, two putative adhesin b genes, hi0119 and hi0362, have been identified on the basis of homology to the adhesin b (fima) of streptococcus parasanguis. we expressed and characterized one of them, hi0119, from a non-typeable h. influenzae strain (nthi). this 37 kda protein was selectively isolated from an h. influenzae surface protein (water) extract by elution from a celite matrix with edta. the adhesin b protein is 97.7% identical to that of h. influenzae, ... | 1998 | 9711849 |
| construction and analysis of a streptococcus parasanguis reca mutant: homologous recombination is not required for adhesion in an in vitro tooth surface model. | pcr was used to amplify an internal region of the reca gene from streptococcus parasanguis fw213. the pcr fragment was used as a probe to recover the entire streptococcal reca gene from an s. parasanguis genomic library, and the sequence of the gene was determined. the deduced product of the s. parasanguis reca gene showed a high degree of amino acid identity with other prokaryotic reca proteins. the cloned reca sequence was disrupted in vitro by insertional mutagenesis, and the mutated allele w ... | 1999 | 9864313 |
| streptococcus parasanguinis: new pathogen associated with asymptomatic mastitis in sheep. | we describe two unusual cases in sheep of subclinical mastitis caused by streptococcus parasanguinis. this bacterium has been associated with the development of experimental endocarditis; its presence at relatively high concentrations in apparently healthy sheep milk may pose a health risk in persons with predisposing heart lesions. | 1998 | 9866743 |
| fur and iron transport proteins in the brazilian purpuric fever clone of haemophilus influenzae biogroup aegyptius. | the brazilian purpuric fever (bpf) clone of haemophilus influenzae biogroup aegyptius causes a fatal septicaemic disease, resembling fulminant meningococcal sepsis, in children. when isolate f3031 was grown under iron-limiting conditions, the presence of several iron-regulated proteins of 38-110 kda was revealed by electrophoretic analysis and a fur homologue was shown by immunoblotting. dot-blot assays and immunoblotting indicated that bpf cells bound human transferrin and contained transferrin ... | 1999 | 10403413 |
| streptococcus parasanguis pepo encodes an endopeptidase with structure and activity similar to those of enzymes that modulate peptide receptor signaling in eukaryotic cells. | studies in our laboratory have identified two fimbria-associated adhesins, fima and fap1, of streptococcus parasanguis fw213. in this study, we isolated and sequenced dna fragments linked to fima to determine if they contained additional factors associated with adherence, virulence, or survival in the host. an open reading frame just upstream and divergently transcribed from the fima operon was identified and named pepo. northern hybridization indicated that pepo is transcribed as a monocistroni ... | 1999 | 10496897 |
| 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 |
| prevalence of the amylase-binding protein a gene (abpa) in oral streptococci. | salivary amylase binds specifically to a number of oral streptococcal species. this interaction may play an important role in dental plaque formation. recently, a 585-bp gene was cloned and sequenced from streptococcus gordonii challis encoding a 20.5-kda amylase-binding protein (abpa). the goal of this study was to determine if related genes are present in other species of oral streptococci. biotinylated abpa was used in southern blot analysis to screen genomic dna from several strains represen ... | 1999 | 10565935 |
| identification of dipeptide repeats and a cell wall sorting signal in the fimbriae-associated adhesin, fap1, of streptococcus parasanguis. | fap1, a fimbriae-associated protein, is involved in fimbriae assembly and adhesion of streptococcus parasanguis fw213 (wu et al., 1998). in this study, the sequence of the fap1 gene was resolved using a primer island transposition system. sequence analysis indicated that fap1 was composed of 7659 nucleotides. the predicted fap1 protein contains an unusually long signal sequence (50 amino acid residues), a cell wall sorting signal and two repeat regions. repeat regions i and ii have a similar dip ... | 1999 | 10594831 |
| glycosylation of homologous immunodominant proteins of ehrlichia chaffeensis and ehrlichia canis. | the glycoprotein genes of ehrlichia chaffeensis (1,644 bp) and ehrlichia canis (2,064 bp) encode proteins of 548 to 688 amino acids with predicted molecular masses of only 61 and 73 kda but with electrophoretic mobilities of 120 kda (p120) and 140 kda (p140), respectively. the 120-kda protein gene of e. chaffeensis contains four identical 240-bp tandem repeat units, and the 140-kda protein gene of e. canis has 14 nearly identical, tandemly arranged 108-bp repeat units. conserved serine-rich moti ... | 2000 | 10603362 |
| crohn disease arthropathy: antigens in synovial fluid share epitopes with strains of two species of viridans streptococci. | there is evidence to suggest that crohn disease is caused by an immunologic response to an unknown intestinal luminal antigen, probably of bacterial origin. the reported demonstration of yersinia antigen in the synovial fluid of patients with yersinosis therefore prompted a search for bacterial antigens in the synovial fluid of patients with crohn arthropathy. | 2000 | 10766323 |
| characterization of a streptococcal endopeptidase with homology to human endothelin-converting enzyme. | a gene encoding an endopeptidase from streptococcus parasanguis fw213 has been cloned and shown to have high sequence homology to genes encoding mammalian metalloendopeptidases. the gene, designated s. parasanguis pepo, was cloned into the pet28a expression vector, resulting in a fusion of vector sequences encoding a hexahistidine tag at the carboxyl terminus. the recombinant pepo (rpepo) was expressed in escherichia coli and purified using an ni(2+) affinity column. polyclonal antiserum to rpep ... | 2001 | 11119489 |
| hla-dr4 and salivary immunoglobulin a reactions to oral streptococci. | the aim of this study was to describe and compare salivary immunoglobulin a (iga) antibody reactions to extracts of strains of three oral streptococci in human leukocyte antigen (hla)-dr4-positive and -dr4-negative subjects. whole paraffin-stimulated saliva samples were collected from 27 apparently healthy subjects. previous hla typing showed that 20 subjects were dr4 positive and 7 were dr4 negative. hla-drb1*04 subtyping was performed among the dr4-positive subjects. whole-cell antigen extract ... | 2001 | 11169139 |
| mannosidase production by viridans group streptococci. | the production of mannosidase activity by all currently recognized species of human viridans group streptococci was determined using an assay in which bacterial growth was dependent on the degradation of the high-mannose-type glycans of rnase b and subsequent utilization of released mannose. rnase b is an excellent substrate for the demonstration of mannosidase activity since it is a glycoprotein with a single glycosylation site which is occupied by high-mannose-type glycoforms containing five t ... | 2001 | 11230417 |
| streptococcus parasanguis fimbria-associated adhesin fap1 is required for biofilm formation. | the sanguis streptococci are primary colonizers of the tooth surface and thus form the foundation for the complex multiple species biofilm known as dental plaque. in addition, these bacteria can colonize native and prosthetic heart valves and are a common cause of endocarditis. little is known about the molecular mechanisms governing multiple or single species biofilm development within this group of organisms. using an in vitro assay for biofilm formation, we determined that (i) streptococcus p ... | 2001 | 11254614 |
| molecular strategies for fimbrial expression and assembly. | fimbriae or pili are long, filamentous, multimeric macromolecules found on the bacterial cell surface. bacteria express a diverse array of fimbriae or pili that are involved in bacterial adherence and invasion. fimbriae can be categorized based on their modes of expression and assembly. type i fimbriae and p pili are distributed peritrichously and translocated to the cell surface by a chaperone/usher pathway. type 4 pili are located at the pole of the cell and assembled via the type ii secretion ... | 2001 | 11345521 |
| expression of streptococcus mutans fima is iron-responsive and regulated by a dtxr homologue. | iron uptake, transport and storage in streptococcus mutans, the principal causative agent of human dental cavities, is unexplored despite early reports in the literature which predict a role for this trace metal in cariogenesis. experiments in the authors' laboratory revealed several iron-responsive proteins in s. mutans, one of which reacted with a polyclonal antiserum directed against the fima fimbrial adhesin from streptococcus parasanguis on western blots. the results of western blot and nor ... | 2001 | 11390691 |
| vaccination with fima from streptococcus parasanguis protects rats from endocarditis caused by other viridans streptococci. | the fima protein of streptococcus parasanguis is a virulence factor in the rat model of endocarditis, and immunization with fima protects rats against homologous bacterial challenge. because fima-like proteins are widespread among the oral streptococci, the leading cause of native valve endocarditis, we evaluated the ability of this vaccinogen to protect rats when challenged by other streptococcal species. here we report that fima vaccination produced antibodies that cross-reacted with and prote ... | 2002 | 11748213 |
| evidence that orf3 at the streptococcus parasanguis fima locus encodes a thiol-specific antioxidant. | streptococcus parasanguis is a primary colonizer of dental plaque and a major player in subacute bacterial endocarditis. in the present study, the authors report that an orf (orf3) located 77 bp downstream of the fima operon on the s. parasanguis fw213 chromosome complements an escherichia coli thiol peroxidase (tpx) mutation in glutamine synthetase (gs) protection assays and that gs is protected by the orf3 gene product in s. parasanguis cell extracts. in addition, the putative streptococcal pe ... | 2002 | 11882710 |
| the divergently transcribed streptococcus parasanguis virulence-associated fima operon encoding an mn(2+)-responsive metal transporter and pepo encoding a zinc metallopeptidase are not coordinately regulated. | the study of how bacteria respond to and obtain divalent metal ions provides insight into the regulation of virulence factors in the host environment. regulation of metal permease operons in gram-positive bacteria may involve the binding of metal-responsive repressors to palindromic domains in their control regions. the streptococcus parasanguis fima operon, which encodes an atp-binding cassette (abc) transporter system with sequence homology to the lrai family of metal transporters, possesses a ... | 2002 | 12228300 |
| construction of a novel transposon mutagenesis system useful in the isolation of streptococcus parasanguis mutants defective in fap1 glycosylation. | streptococcus parasanguis, a primary colonizer of the tooth surface, has long, peritrichous fimbriae. a fimbria-associated protein, fap1, is identified as an adhesin of s. parasanguis fw213. the mature fap1 protein is glycosylated, and the glycosylation is required for fimbria biogenesis and bacterial adhesion. little is known about the mechanism of fap1 glycosylation due to the lack of identifiable mutants. a novel transposon mutagenesis system was established and used to generate a mutant libr ... | 2002 | 12438322 |
| double-chambered right ventricle associated with mural and pulmonic valve endocarditis: description of a clinical case and review of the literature. | a double-chambered right ventricle is a relatively uncommon congenital cardiac defect characterized by the presence of anomalous muscle bundles dividing the right ventricle into a high-pressure proximal chamber and a low-pressure distal chamber. this pathology is often wrongly diagnosed in adult patients. we report the first case of a patient with double-chambered right ventricle associated with a mural and pulmonic valve endocarditis caused by streptococcus parasanguis diagnosed with two-dimens ... | 2004 | 14961798 |
| salivary iga reactions to cell-surface antigens of oral streptococci. | in the immunoblot technique, using whole bacteria cell extracts as antigens, both intra- and extracellular antigens are detected, which gives a large number of immunoglobulin a (iga) reactions (immunoblot bands) when incubated with saliva. it is important to distinguish which immunoblot bands represent bacterial cell-surface antigens, since these antigens could be involved in adhesion mechanisms and be available for blocking in vivo. | 2004 | 15107071 |
| investigating the role of seca2 in secretion and glycosylation of a fimbrial adhesin in streptococcus parasanguis fw213. | adhesion of streptococcus parasanguis fw213, a primary colonizer, to the tooth surface is mediated mainly by peritrichous long fimbriae. the fimbrial structural unit, fap1, is indispensable for fimbriae biogenesis, adhesion to an in vitro tooth model and biofilm formation. mature fap1 is a glycoprotein with an apparent molecular mass of 200 kda. glycosylated fap1 is not present in some mutants screened from a transposon mutant library. localization of the transposition sites revealed a gene dete ... | 2004 | 15255897 |
| naso-orbicular tissue necrosis by streptococcus parasanguis in a patient with fanconi anemia: clinical and laboratory aspects. | fanconi anemia (fa) is a rare autosomal recessive disorder, characterized by pancytopenia and progressive hypoplasia of the bone marrow. a 23-year-old woman with fa showed severe pancytopenia and developed an abscess on the infraorbicular region on the right side of the face that progressed to phlegmon and caused tissue necrosis of the nostrils, nasal septum, nasal fossa, and posterior orbital region. laboratory examination showed streptococcus parasanguis as the etiologic agent of the phlegmon. ... | 2004 | 15259974 |
| an unusual endocarditis-induced crescentic glomerulonephritis treated by plasmapheresis. | a 58-year-old man presented with fever and a rapidly progressive glomerulonephritis. an infective endocarditis due to streptococcus parasanguis was diagnosed. a renal biopsy revealed type iii pauci-immune crescentic glomerulonephritis. as first-line therapy, antibiotics were administered alone. faced to the unsuccessful anti-infective approach, corticosteroid therapy was added as a second-line therapy. finally, plasmapheresis introduced as the third-line therapy, significantly improved renal fun ... | 2004 | 15630906 |
| low salivary iga activity to cell-surface antigens of mutans streptococci related to hla-drb1*04. | mutans streptococci are found in almost all individuals, though there are large differences in colonization levels between individuals. these differences are not readily explained, though several factors are believed to influence the colonization. one factor is the immune response to mutans streptococci, mainly provided by salivary immunoglobulin a (iga). in a previous study, differences in salivary iga reactions to oral streptococci were observed between human leukocyte antigen (hla)-dr4-positi ... | 2005 | 15720566 |
| association of a novel high molecular weight, serine-rich protein (srpa) with fibril-mediated adhesion of the oral biofilm bacterium streptococcus cristatus. | the surface of the oral plaque bacterium streptococcus cristatus is decorated with a lateral tuft of fibrils. the fibrillar tuft functions in the adhesion of s. cristatus to heterologous bacterial species in the plaque biofilm. the tuft typically consists of a densely packed fringe of shorter fibrils 238 +/- 19 nm long with longer, less abundant fibrils 403 +/- 66 nm long projecting through the fringe of short fibrils. the two types of fibrils in the tufts of s. cristatus have been refractory to ... | 2005 | 15836513 |
| the maintenance in the oral cavity of children of tetracycline-resistant bacteria and the genes encoding such resistance. | to investigate the maintenance of tetracycline-resistant oral bacteria and the genes encoding tetracycline resistance in these bacteria in children (aged 4--6 years) over a period of 12 months. | 2005 | 16027144 |
| microbial risk indicators of early childhood caries. | the aim of this study was to use molecular identification methods, such as 16s rna gene sequence and reverse-capture checkerboard hybridization, for identification of the bacteria associated with dental caries and with dental health in a subset of 204 twins aged 1.5 to 7 years old. a total of 448 plaque samples (118 collected from caries-free subjects and 330 from caries-active subjects) were used for analysis. we compared the bacteria found in biofilms of children exhibiting severe dental carie ... | 2005 | 16272513 |
| relationship between the ability of oral streptococci to interact with platelet glycoprotein ibalpha and with the salivary low-molecular-weight mucin, mg2. | the oral streptococci streptococcus sanguinis, streptococcus gordonii and streptococcus oralis are common aetiological agents of infective endocarditis, and their ability to adhere to and induce the aggregation of platelets is thought to be a virulence trait. the platelet glycoprotein gpibalpha has been implicated as the adhesion receptor for s. sanguinis and s. gordonii, but it is not known if this is the case for s. oralis and other species. the aim of this study was to determine the gpibalpha ... | 2006 | 17069618 |
| the glycan moieties and the n-terminal polypeptide backbone of a fimbria-associated adhesin, fap1, play distinct roles in the biofilm development of streptococcus parasanguinis. | fap1, a fimbria-associated glycoprotein, is essential for biofilm formation of streptococcus parasanguinis and mediates bacterial attachment to saliva-coated hydroxylapatite, an in vitro tooth model (e. h. froeliger and p. m. fives-taylor, infect. immun. 69:2512-2519, 2001; h. wu and p. m. fives-taylor, mol. microbiol. 34:1070-1081, 1999; h. wu et al., mol. microbiol. 28:487-500, 1998). fap1 belongs to a growing family of high-molecular-weight serine-rich proteins found in streptococcal and stap ... | 2007 | 17296746 |
| role of gap3 in fap1 glycosylation, stability, in vitro adhesion, and fimbrial and biofilm formation of streptococcus parasanguinis. | streptococcus parasanguinis is a primary colonizer of the tooth surface. its adhesion is mediated by the long fimbriae, which are composed of multiple subunits of a serine-rich glycoprotein, fap1. previous studies revealed that a chromosomal region located downstream of fap1 is involved in the secretion and glycosylation of fap1. in this study, we investigated the role of a glycosylation-associated gene, gap3, in fap1 biogenesis. | 2008 | 18173801 |
| identification of critical residues in gap3 of streptococcus parasanguinis involved in fap1 glycosylation, fimbrial formation and in vitro adhesion. | streptococcus parasanguinis is a primary colonizer of human tooth surfaces and plays an important role in dental plaque formation. bacterial adhesion and biofilm formation are mediated by long peritrichous fimbriae that are composed of a 200 kda serine rich glycoprotein named fap1 (fimbriae-associated protein). glycosylation and biogenesis of fap1 are modulated by a gene cluster downstream of the fap1 locus. a gene encoding a glycosylation-associated protein, gap3, was found to be important for ... | 2008 | 18371226 |
| penicillin g-resistant viridans group streptococcal endocarditis and interpretation of the american heart association's guidelines for the treatment of infective endocarditis. | we report a case of endocarditis due to a penicillin-"resistant" streptococcus parasanguinis, discuss interpretations of the american heart association's guidelines for the treatment of viridans group streptococcal infection, and comment on therapy for infective endocarditis due to penicillin-resistant viridans group streptococci. | 2008 | 18444825 |
| a new twist on an old pathway--accessory sec [corrected] systems. | the export of proteins from their site of synthesis in the cytoplasm across the inner membrane is an important aspect of bacterial physiology. because the location of extracytoplasmic proteins is ideal for host-pathogen interactions, protein export is also important to bacterial virulence. in bacteria, there are conserved protein export systems that are responsible for the majority of protein export: the general secretion (sec) pathway and the twin-arginine translocation pathway. in some bacteri ... | 2008 | 18544071 |
| a conserved domain of previously unknown function in gap1 mediates protein-protein interaction and is required for biogenesis of a serine-rich streptococcal adhesin. | fap1-like serine-rich proteins are a new family of bacterial adhesins found in a variety of streptococci and staphylococci that have been implicated in bacterial pathogenesis. a gene cluster encoding glycosyltransferases and accessory sec components is required for fap1 glycosylation and biogenesis in streptococcus parasanguinis. here we report that the glycosylation-associated protein, gap1, contributes to glycosylation and biogenesis of fap1 by interacting with another glycosylation-associated ... | 2008 | 18826412 |
| a conserved c-terminal 13-amino-acid motif of gap1 is required for gap1 function and necessary for the biogenesis of a serine-rich glycoprotein of streptococcus parasanguinis. | adhesion of streptococcus parasanguinis to saliva-coated hydroxyapatite (sha), an in vitro tooth model, is mediated by long peritrichous fimbriae. fap1, a fimbria-associated serine-rich glycoprotein, is required for fimbrial assembly. biogenesis of fap1 is controlled by an 11-gene cluster that contains gly, nss, galt1 and -2, secy2, gap1 to -3, seca2, and gtf1 and -2. we had previously isolated a collection of nine nonadherent mutants using random chemical mutagenesis approaches. these mutants f ... | 2008 | 18852249 |
| glycosylation and biogenesis of a family of serine-rich bacterial adhesins. | glycosylation of bacterial proteins is an important process for bacterial physiology and pathophysiology. both o- and n-linked glycan moieties have been identified in bacterial glycoproteins. the n-linked glycosylation pathways are well established in gram-negative bacteria. however, the o-linked glycosylation pathways are not well defined due to the complex nature of known o-linked glycoproteins in bacteria. in this review, we examine a new family of serine-rich o-linked glycoproteins which are ... | 2009 | 19202081 |
| molecular characterization of macrolide resistance determinants [erm(b) and mef(a)] in streptococcus pneumoniae and viridans group streptococci (vgs) isolated from adult patients with cystic fibrosis (cf). | although long-term use of azithromycin has shown a significant clinical improvement for patients with cystic fibrosis (cf), its long-term effect on the susceptibility of commensal flora within cf airways has not yet been examined. we therefore suggest that long-term use of azithromycin increases macrolide resistance in commensal streptococci. | 2009 | 19584106 |
| purification and characterization of an active n-acetylglucosaminyltransferase enzyme complex from streptococci. | a new family of bacterial serine-rich repeat glycoproteins can function as adhesins required for biofilm formation and pathogenesis in streptococci and staphylococci. biogenesis of these proteins depends on a gene cluster coding for glycosyltransferases and accessory secretion proteins. previous studies show that fap1, a member of this family from streptococcus parasanguinis, can be glycosylated by a protein glycosylation complex in a recombinant heterogeneous host. here we report a tandem affin ... | 2010 | 20971868 |
| molecular characterization and phylogenetic analysis of quinolone resistance-determining regions (qrdrs) of gyra, gyrb, parc and pare gene loci in viridans group streptococci isolated from adult patients with cystic fibrosis. | ciprofloxacin is the most frequently used member of the fluoroquinolones during initial eradication therapy of pseudomonas aeruginosa, as well as during acute pulmonary exacerbations. however, its long-term effect on the susceptibility of the commensal flora within the cystic fibrosis (cf) airways has not yet been examined. the aim of this study was therefore to examine the consequence of oral ciprofloxacin usage on the resistance of the commensal viridans group streptococci (vgs), in terms of m ... | 2010 | 21193474 |
| crystallization and initial crystallographic analysis of the streptococcus parasanguinis fw213 fap1-nra adhesive domain at ph 5.0. | the adhesin fimbriae-associated protein 1 (fap1) is a surface protein of streptococcus parasanguinis fw213 and plays a major role in the formation of dental plaque in humans. increased adherence is highly correlated to a reduction in ph and acid activation has been mapped to a subdomain: fap1-nr(a). here, fap1-nr(a) has been crystallized at ph 5.0 and diffraction data have been collected to 3.0 å resolution. the crystals belonged to space group p4(1)2(1)2 or p4(3)2(1)2, with unit-cell parameters ... | 2011 | 21301104 |
| phylogenetic analyses and detection of viridans streptococci based on sequences and denaturing gradient gel electrophoresis of the rod shape-determining protein gene. | population analysis of viridans streptococci is important because these species are associated with dental caries, bacteremia, and subacute endocarditis, in addition to being important members of the human oral commensal microbiota. | 2009 | 21523207 |
| plasmid pfw213: properties and construction of a shuttle vector with the oral streptococcal origin. | streptococcus parasanguinis is among the most successful colonizers of the human body. strain fw213 harbors a 7.0-kb cryptic plasmid, pfw213, with a copy number at 5 to 10 per chromosome. sequence and functional analyses of pfw213 revealed that the open reading frame (orf) encoding the replication protein (rep) is essential for the replication of pfw213, and the putative plasmid addiction system (relb and rele) and an orf (orf6) with no known function are required for the stability. the minimal ... | 2011 | 21531841 |
| structural and functional analysis of a new subfamily of glycosyltransferases required for glycosylation of serine-rich streptococcal adhesins. | serine-rich repeat glycoproteins (srrps) are a growing family of bacterial adhesins found in many streptococci and staphylococci; they play important roles in bacterial biofilm formation and pathogenesis. glycosylation of this family of adhesins is essential for their biogenesis. a glucosyltransferase (gtf3) catalyzes the second step of glycosylation of a srrp (fap1) from an oral streptococcus, streptococcus parasanguinis. although gtf3 homologs are highly conserved in srrp-containing streptococ ... | 2011 | 21653318 |
| a molecular chaperone mediates a two-protein enzyme complex and glycosylation of serine-rich streptococcal adhesins. | serine-rich repeat glycoproteins identified from streptococci and staphylococci are important for bacterial adhesion and biofilm formation. two putative glycosyltransferases, gtf1 and gtf2, from streptococcus parasanguinis form a two-protein enzyme complex that is required for glycosylation of a serine-rich repeat adhesin, fap1. gtf1 is a glycosyltransferase; however, the function of gtf2 is unknown. here, we demonstrate that gtf2 enhances the enzymatic activity of gtf1 by its chaperone-like pro ... | 2011 | 21862581 |
| canonical seca associates with an accessory secretory protein complex involved in biogenesis of a streptococcal serine-rich repeat glycoprotein. | fap1, a serine-rich repeat glycoprotein (srrp), is required for bacterial biofilm formation of streptococcus parasanguinis. fap1-like srrps are found in many gram-positive bacteria and have been implicated in bacterial fitness and virulence. a conserved five-gene cluster, secy2-gap1-gap2-gap3-seca2, located immediately downstream of fap1, is required for fap1 biogenesis. seca2, gap1, and gap3 encode three putative accessory sec proteins. seca2 mediates export of mature fap1, and gap1 and gap3 ar ... | 2011 | 21965576 |
| structural insight into the role of streptococcus parasanguinis fap1 within oral biofilm formation. | the fimbriae-associated protein 1 (fap1) is a major adhesin of streptococcus parasanguinis, a primary colonizer of the oral cavity that plays an important role in the formation of dental plaque. fap1 is an extracellular adhesive surface fibre belonging to the serine-rich repeat protein (srrp) family, which plays a central role in the pathogenesis of streptococci and staphylococci. the n-terminal adhesive region of fap1 (fap1-nr) is composed of two domains (fap1-nr(α) and fap1-nr(β)) and is proje ... | 2011 | 22166217 |
| microbiota of severe early childhood caries before and after therapy. | severe early childhood caries (ecc) is difficult to treat successfully. this study aimed to characterize the microbiota of severe ecc and evaluate whether baseline or follow-up microbiotas are associated with new lesions post-treatment. plaque samples from 2- to 6-year-old children were analyzed by a 16s rrna-based microarray and by pcr for selected taxa. severe-ecc children were monitored for 12 months post-therapy. by microarray, species associated with severe-ecc (n = 53) compared with caries ... | 2011 | 21868693 |
| uv-c-irradiation sublethal stress does not alter antibiotic susceptibility of the viridans group streptococci to β-lactam, macrolide, and fluoroquinolone antibiotic agents. | previous work has indicated that environmental stresses on bacteria might lead to an upregulation of stress response. led curing lights (315-400 nm) and other uv lights used in tooth whitening cosmetic procedures might act as stresses. we examined the effect of uv-c light, as a high-energy surrogate to the lower-energy uv-a light used in such instruments, to examine its effect on the antibiotic susceptibility of viridans group streptococci. | 2011 | 22887906 |
| fastannotator--an efficient transcript annotation web tool. | recent developments in high-throughput sequencing (hts) technologies have made it feasible to sequence the complete transcriptomes of non-model organisms or metatranscriptomes from environmental samples. the challenge after generating hundreds of millions of sequences is to annotate these transcripts and classify the transcripts based on their putative functions. because many biological scientists lack the knowledge to install linux-based software packages or maintain databases used for transcri ... | 2012 | 23281853 |
| gtfa and gtfb are both required for protein o-glycosylation in lactobacillus plantarum. | acm2, the major autolysin of lactobacillus plantarum wcfs1, was recently found to be o-glycosylated with n-acetylhexosamine, likely n-acetylglucosamine (glcnac). in this study, we set out to identify the glycosylation machinery by employing a comparative genomics approach to identify gtf1 homologues, which are involved in fimbria-associated protein 1 (fap1) glycosylation in streptococcus parasanguinis. this in silico approach resulted in the identification of 6 candidate l. plantarum wcfs1 genes ... | 2014 | 24532775 |
| engineering and dissecting the glycosylation pathway of a streptococcal serine-rich repeat adhesin. | serine-rich repeat glycoproteins (srrps) are conserved in gram-positive bacteria. they are crucial for modulating biofilm formation and bacterial-host interactions. glycosylation of srrps plays a pivotal role in the process; thus understanding the glycosyltransferases involved is key to identifying new therapeutic drug targets. the glycosylation of fap1, an srrp of streptococcus parasanguinis, is mediated by a gene cluster consisting of six genes: gtf1, gtf2, gly, gtf3, dgt1, and galt2 mature fa ... | 2016 | 28039332 |
| comparison of oral microbiota in tumor and non-tumor tissues of patients with oral squamous cell carcinoma. | bacterial infections have been linked to malignancies due to their ability to induce chronic inflammation. we investigated the association of oral bacteria in oral squamous cell carcinoma (oscc/tumor) tissues and compared with adjacent non-tumor mucosa sampled 5 cm distant from the same patient (n = 10). by using culture-independent 16s rrna approaches, denaturing gradient gel electrophoresis (dgge) and cloning and sequencing, we assessed the total bacterial diversity in these clinical samples. | 2012 | 22817758 |
| evaluation of the nanosphere verigene gram-positive blood culture assay with the versatrek blood culture system and assessment of possible impact on selected patients. | the verigene gram-positive blood culture (bc-gp) assay (nanosphere, northbrook, il) is a molecular method for the rapid identification of gram-positive organisms and resistance markers directly from blood culture bottles. a total of 148 versatrek redox 1 40-ml aerobic bottles demonstrating gram-positive bacteria were tested. results were compared with those from conventional biochemical and matrix-assisted laser desorption ionization-time of flight (maldi-tof) identifications. we obtained isolat ... | 2013 | 24048531 |
| 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 |
| antibiotic susceptibility of commensal bacteria from human milk. | recent studies have focused on foodborne or commensal bacteria as vehicles of antibiotic resistance. however, the antibiotic resistance of milk bacteria from healthy donors is still vague in taiwan. for this purpose, human milk samples were obtained from randomly recruited 19 healthy women between 3 and 360 days post-partum. antibiotic susceptibility profile of bacteria from milk samples was determined. about 20 bacterial species were isolated from milk samples including staphylococcus (6 specie ... | 2016 | 26494365 |
| influence of the magnetic field on microorganisms in the oral cavity. | since the beginning of their lives, all living organisms are exposed to the influence of geomagnetic fields. | 2017 | 26018310 |
| daptomycin activity against uncommonly isolated streptococcal and other gram-positive species groups. | a total of 1,356 clinical isolates were tested against daptomycin by broth microdilution methods. daptomycin was active against seven groups of viridans group streptococci (mic50 and mic90 values ranging from ≤0.06 and ≤0.06 μg/ml [streptococcus bovis and streptococcus dysgalactiae] to 0.5 and 1 μg/ml [streptococcus mitis, streptococcus oralis, and streptococcus parasanguinis], respectively), beta-hemolytic streptococci serogroups c, f, and g (mic50 and mic90, ≤0.06 to 0.25 and 0.12 to 0.25 μg/m ... | 2013 | 24080651 |
| bacterial adhesion on the titanium and zirconia abutment surfaces. | microorganisms harboring the oral cavity, mainly those related to periodontal diseases, are the most potential etiologic factor of failure in long-term implant treatment. the material used for abutment components may influence the adhesion and colonization of microbial species. the aim of this in vivo investigation was to evaluate the biofilm formation on machined (mpt) or cast titanium (cpt) and zirconia abutments (zc). | 2014 | 23316996 |
| is the whole greater than the sum of its parts? de novo assembly strategies for bacterial genomes based on paired-end sequencing. | whole genome sequence construction is becoming increasingly feasible because of advances in next generation sequencing (ngs), including increasing throughput and read length. by simply overlapping paired-end reads, we can obtain longer reads with higher accuracy, which can facilitate the assembly process. however, the influences of different library sizes and assembly methods on paired-end sequencing-based de novo assembly remain poorly understood. | 2015 | 26315384 |
| engineering and dissecting the glycosylation pathway of a streptococcal serine-rich repeat adhesin. | serine-rich repeat glycoproteins (srrps) are conserved in gram-positive bacteria. they are crucial for modulating biofilm formation and bacterial-host interactions. glycosylation of srrps plays a pivotal role in the process, thus understanding the glycosyltransferases involved is key to identifying new therapeutic drug targets. the glycosylation of fap1, an srrp of streptococcus parasanguinis, is mediated by a gene cluster consisting of six genes, gtf1, gtf2, gly, gtf3, dgt1 and galt2. mature fa ... | 2016 | 27875303 |
| gap2 promotes the formation of a stable protein complex required for mature fap1 biogenesis. | serine-rich repeat glycoproteins (srrps) are important bacterial adhesins conserved in streptococci and staphylococci. fap1, a srrp identified in streptococcus parasanguinis, is the major constituent of bacterial fimbriae and is required for adhesion and biofilm formation. an 11-gene cluster is required for fap1 glycosylation and secretion; however, the exact mechanism of fap1 biogenesis remains a mystery. two glycosylation-associated proteins within this cluster--gap1 and gap3--function togethe ... | 2013 | 23475979 |
| 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 |
| the expression of the fim operon is crucial for the survival of streptococcus parasanguinis fw213 within macrophages but not acid tolerance. | the acquisition of transition metal ions is essential for the viability and in some cases the expression of virulence genes in bacteria. the fimcba operon of streptococcus parasanguinis fw213 encodes a mn(2+)/fe(2+)-specific atp-binding cassette transporter. fima, a lipoprotein in the system, is essential for the development of endocarditis, presumably by binding to fibrin monolayers on the damaged heart tissue. recent sequence analysis revealed that spaf_0344 was homologous to streptococcus gor ... | 2013 | 23823757 |
| streptococcal diversity of human milk and comparison of different methods for the taxonomic identification of streptococci. | the genus streptococcus is 1 of the dominant bacterial groups in human milk, but the taxonomic identification of some species remains difficult. | 2016 | 26261225 |
| glycosyltransferase-mediated sweet modification in oral streptococci. | bacterial glycosyltransferases play important roles in bacterial fitness and virulence. oral streptococci have evolved diverse strategies to survive and thrive in the carbohydrate-rich oral cavity. in this review, we discuss 2 important biological processes mediated by 2 distinct groups of glycosyltransferases in oral streptococci that are important for bacterial colonization and virulence. the first process is the glycosylation of highly conserved serine-rich repeat adhesins by a series of glyc ... | 2015 | 25755271 |
| antimicrobial activity of the synthetic peptide lys-a1 against oral streptococci. | the peptide lys-[trp(6)]-hy-a1 (lys-a1) is a synthetic derivative of the peptide hy-a1, initially isolated from the frog species hypsiboas albopunctatus. according to previous research, it is a molecule with broad antimicrobial activity. the objective of this study was to evaluate the antimicrobial activity of the synthetic peptide lys-a1 (kifgaiwplalgalknlik-nh2) on the planktonic and biofilm growth of oral bacteria. the methods used to evaluate antimicrobial activity include the following: det ... | 2013 | 23340019 |
| a rare cause of primary aortoenteric fistula: streptococcus parasanguinis aortitis. | primary aortoenteric fistula is a rare cause of upper gastrointestinal bleed but can lead to significant mortality if the diagnosis is delayed. aortitis, characterized by inflammation of the aortic wall, is a rare cause of aortoenteric fistula. we present a case report of a 72-year-old male patient with infectious aortoenteric fistula secondary to streptococcus parasanguinis, along with a review of the literature. this case demonstrates the importance of early diagnosis and aggressive surgical t ... | 2017 | 28255476 |
| new helical binding domain mediates a glycosyltransferase activity of a bifunctional protein. | serine-rich repeat glycoproteins (srrps) conserved in streptococci and staphylococci are important for bacterial colonization and pathogenesis. fap1, a well studied srrp is a major surface constituent of streptococcus parasanguinis and is required for bacterial adhesion and biofilm formation. biogenesis of fap1 is a multistep process that involves both glycosylation and secretion. a series of glycosyltransferases catalyze sequential glycosylation of fap1. we have identified a unique hybrid prote ... | 2016 | 27539847 |
| [a patient with a wedge-shaped pulmonary lesion associated with streptococcus parasanguinis]. | an 84-year-old man was admitted to our hospital with bloody sputum. he was found to have a right lower lobe wedge-shaped nodular lesion with chest x-ray and computed tomography of the chest. ceftriaxone and minocycline were started empirically based on a working diagnosis of community-acquired pneumonia. streptococcus parasanguinis was isolated with sputum cultures obtained on three consecutive days and was identified based on its biochemical properties. s. parasanguinis is a member of the sangu ... | 2016 | 27529967 |
| streptococcusmarmotae sp. nov., isolated from the respiratory tract of marmota himalayana. | five strains of a gram-stain-positive, catalase-negative, α-haemolytic, coccus-shaped chain-forming organism were isolated separately from the lower respiratory tracts of five animals of marmota himalayana in the endemic area of plague, the qinghai-tibet plateau, china. based on their morphological characteristics, biochemical features and molecular phylogenetic studies, the strains were placed as representing a new member of the genus streptococcus. comparative 16s rrna gene sequence studies in ... | 2016 | 27473166 |
| genome anatomy of streptococcus parasanguinis strain c1a, isolated from a patient with acute exacerbation of chronic obstructive pulmonary disease, reveals unusual genomic features. | streptococcus parasanguinis causes invasive diseases. however, the mechanism by which it causes disease remains unclear. here, we describe the complete genome sequence of s. parasanguinis c1a, isolated from a patient diagnosed with an acute exacerbation of chronic obstructive pulmonary disease. several genes that might be associated with pathogenesis are also described. | 2015 | 26021924 |
| the highly conserved domain of unknown function 1792 has a distinct glycosyltransferase fold. | more than 33,000 glycosyltransferases have been identified. structural studies, however, have only revealed two distinct glycosyltransferase (gt) folds, gt-a and gt-b. here we report a 1.34-å resolution x-ray crystallographic structure of a previously uncharacterized 'domain of unknown function' 1792 (duf1792) and show that the domain adopts a new fold and is required for glycosylation of a family of serine-rich repeat streptococcal adhesins. biochemical studies reveal that the domain is a gluco ... | 2014 | 25023666 |
| nmr assignment of the amylase-binding protein a from streptococcus parasanguinis. | streptococcus parasanguinis is a primary colonizer of tooth surfaces in the oral cavity. amylase-binding protein a (abpa) from s. parasanguinis is responsible for the recruitment of salivary amylase to bacterial surface, which plays an important role in the development of oral biofilms. here, we describe the essentially complete nmr assignments for abpa. | 2015 | 25016927 |
| 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 |
| fine-tuned production of hydrogen peroxide promotes biofilm formation of streptococcus parasanguinis by a pathogenic cohabitant aggregatibacter actinomycetemcomitans. | balanced bacterial biofilm communities help to maintain host health. disturbance of such balance can lead to bacterial dysbiosis and pathogenesis. however, complex and dynamic bacterial interactions within the biofilm communities are poorly understood. in this study, we used a dual-species biofilm consisting of the periodontal pathogen aggregatibacter actinomycetemcomitans, and a commensal streptococcus parasanguinis to investigate bacterial interactions since the two organisms have been found t ... | 2016 | 27348605 |
| altered bacterial profiles in saliva from adults with caries lesions: a case-cohort study. | the aim of this study was to learn whether presence of caries in an adult population was associated with a salivary bacterial profile different from that of individuals without untreated caries. stimulated saliva samples from 621 participants of the danish health examination survey were analyzed using the human oral microbe identification microarray technology. samples from 174 individuals with dental caries and 447 from a control cohort were compared using frequency and levels of identified bac ... | 2014 | 24643218 |
| complete genome and transcriptomes of streptococcus parasanguinis fw213: phylogenic relations and potential virulence mechanisms. | streptococcus parasanguinis, a primary colonizer of the tooth surface, is also an opportunistic pathogen for subacute endocarditis. the complete genome of strain fw213 was determined using the traditional shotgun sequencing approach and further refined by the transcriptomes of cells in early exponential and early stationary growth phases in this study. the transcriptomes also discovered 10 transcripts encoding known hypothetical proteins, one pseudogene, five transcripts matched to the rfam and ... | 2012 | 22529932 |
| antimicrobial potential of plant extracts and chemical fractions of sideroxylon obtusifolium (roem. & schult.) t.d. penn on oral microorganisms. | the aim of this study is to evaluate the in vitro antimicrobial activity of plant extracts and chemical fractions of sideroxylon obtusifolium t.d. penn on streptococcus mutans, streptococcus oralis, streptococcus salivarius, streptococcus parasanguinis, and candida albicans as well as to identify the chemical classes found in the bioactive extracts possessing better activity. | 2017 | 28512279 |