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biochemical properties of the outer membrane of treponema denticola.the outer membranes (oms) from serovars a, b, and c of treponema denticola, originally isolated from periodontal patients, were prepared. dialysis of the oms against 20 mm mgcl2 yielded the aggregable (a) and the nonaggregable (na) moieties of the oms. the absence of muramic acid, adenosine triphosphatase, hexokinase, and nucleic acid as well as electron microscopy indicated that the om preparations were homogeneous. sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the a and na moiet ...19911715883
characteristics of hemolytic and hemagglutinating activities of treponema denticola.treponema denticola, a suspected periodontal pathogen, was shown to agglutinate and lyse human red blood cells. both activities were cell-associated, heat-labile, and produced during the exponential growth phase. hemolytic activity was time-dependent and required incubation at 37 degrees c; further incubation at 4 degrees c increased the hemolysis. hemagglutination was reduced in the presence of d-glucosamine, edta or sodium salicylate, whereas hemolytic activity was affected by calcium chloride ...19911812467
[first results with a microbiological quick diagnostic procedure in periodontitis].we tested a new diagnostic procedure for the characterization of subgingival plaque in 119 subjects suffering from adult periodontitis. the method can be characterized as a hydrolysis of bana (n-benzoyl-dl-arginine-beta-naphthylamide) by peptidases of porphyromonas gingivalis, bacteroides forsythus and treponema denticola. the result of a positive will be a more or less blue coloured test paper representing the amount of these three peridontal pathogens into the subgingival plaque. after the per ...19911818626
cloning and expression of protease genes from treponema denticola in escherichia coli.a gene bank of random fragments of chromosomal dna from treponema denticola atcc 33520 was constructed in the bacteriophage vector lambda l47.1. the gene bank was plated on escherichia coli c600 and screened for the presence of plaques in which enzyme activity was expressed, using overlays of fluorogenic synthetic substrates and a two-step procedure in which immunological screening was followed by enzyme assays of immunopositive lysates. recombinants expressing trypsin-like, chymotrypsin-like an ...19911840314
pathogen-related spirochetes identified within gingival tissue from patients with acute necrotizing ulcerative gingivitis.the purpose of this investigation was to determine whether monoclonal antibodies against pathogen-restricted antigens of treponema pallidum subsp. pallidum could be used as probes for spirochetes in diseased gingival tissue from subjects with acute necrotizing ulcerative gingivitis. a biotin-streptavidin system was used to identify spirochetes bound by monoclonal antibodies in cryostat sections of tissue. twelve of 16 tissue samples from diseased sites, but none of 8 tissue specimens from health ...19911855985
modeling bacterial damage to pulpal cells in vitro.there is increasing evidence that access to patent dentinal tubules by bacteria and their products rather than trauma from restorative materials is responsible for subsequent pulpitides. the purpose of this study was to compare the relative cytotoxicity of centrifugal fractions of two bacteria, fusobacterium nucleatum and treponema denticola, on l929 cells in monolayer cultures and in the "in vitro pulp chamber." neutrophilic chemotaxis assays and limmulus assays were performed to verify biologi ...19911895035
phylogenetic analysis of the spirochetes.the 16s rrna sequences were determined for species of spirochaeta, treponema, borrelia, leptospira, leptonema, and serpula, using a modified sanger method of direct rna sequencing. analysis of aligned 16s rrna sequences indicated that the spirochetes form a coherent taxon composed of six major clusters or groups. the first group, termed the treponemes, was divided into two subgroups. the first treponeme subgroup consisted of treponema pallidum, treponema phagedenis, treponema denticola, a thermo ...19911917844
sulfhydryl-dependent attachment of treponema denticola to laminin and other proteins.attachment of treponema denticola atcc 35405 to laminin, a major basement membrane protein, and to other proteins was studied. microdilution plates were coated with the proteins, and the attachment of t. denticola was measured by the enzyme-linked immunosorbent assay technique. compared with bovine serum albumin (bsa), t. denticola had a high affinity to laminin, fibronectin, fibrinogen, and gelatin, as well as to type i and type iv collagens. attachment to rgd peptide (gly-arg-gly-asp-ser, the ...19911937780
chemical and biological activities of a 64-kilodalton outer sheath protein from treponema denticola strains.this study examined the distribution of the major outer sheath proteins (mosp) in several treponema denticola strains and reports the isolation of a 64-kda protein from the outer sheath of human clinical isolate t. denticola gm-1. the outer sheath was isolated by freeze-thaw procedures, and the distribution of outer sheath proteins was examined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (sds-page). t. denticola gm-1, ms25, sr-5, and three low-passage clinical isolates possessed ...19911938897
use of monoclonal antibodies to enumerate spirochetes and identify treponema denticola in dental plaque of children, adolescents and young adults.identification of spirochetes in dental plaque is difficult. not all spirochetes can be cultured and microscopic analysis based on darkfield or phase optics cannot determine the genus and species of individual bacterial cells. the purpose of this study was to use monoclonal antibodies in an immunoenzyme technique to stain spirochetes in dental plaque. separate mab were used to estimate total spirochetes and relative numbers of 2 distinct types of treponema denticola. plaque samples were collecte ...19911945493
activation of complement by treponema denticola.oral spirochetes have been shown to be associated with periodontal diseases and are present in increased numbers in lesions of greater severity. in this study, the interaction of treponema denticola with human complement, a major antibacterial defense system, was examined. for each of two strains of t. denticola, it was found that both the classical and alternative pathways of human complement were activated in human serum upon incubation at 37 degrees c. c3 fragments were deposited on the surfa ...19911991867
heat shock response of spirochetes.we examined the heat shock response of the pathogenic spirochetes treponema pallidum, borrelia burgdorferi, and leptospira interrogans and certain saprophytic spirochetes. cellular proteins synthesized after shifts to higher temperatures were [35s]methionine labeled and analyzed by gel electrophoresis and fluorography. only t. pallidum failed to exhibit an obvious heat shock response. groel and dnak homologs were identified in the various species, although these proteins were not thermoinducible ...19912004832
effects of chlorhexidine on proteolytic and glycosidic enzyme activities of dental plaque bacteria.chlorhexidine was tested for its ability to inhibit a wide range of glycosidic and proteolytic enzyme activities produced by treponema denticola, porphyromonas gingivalis, bacteroides intermedius, actinobacillus actinomycemcomitans, capnocytophaga sputigena, capnocytophaga gingivalis, capnocytophaga orchracea, capnocytophaga sp., actinomyces viscosus, streptococcus mitior, streptococcus mutans, streptococcus sobrinus, streptococcus mitis, streptococcus anginosus, streptococcus oralis and strepto ...19912005230
characterization of monoclonal antibodies to two treponema denticola serotypes by the indirect fluorescent-antibody assay.members of the genus treponema have been implicated as possible aetiologic agents of periodontal disease. previously developed murine monoclonal antibodies (mabs) to two treponema denticola strains were characterized by an indirect fluorescent-antibody (ifa) technique. fifteen t. denticola strains and 32 other bacteria commonly isolated from periodontal pockets were used in the screening process. two monoclonal antibodies to t. denticola atcc 33521, serotype b, reacted with five t. denticola iso ...19912030646
molecular cloning and sequence analysis of antigen gene tdpa of treponema denticola.we isolated and characterized an immunogenic protein of an oral spirochete, treponema denticola johnson. a genomic dna library constructed with bacteriophage lambda embl3 as a vector was immunologically screened with a rabbit antiserum against the whole cells. using western immunoblot analysis, we found a particular clone encoding an antigen with a molecular weight of 53,000; we designated the antigen as t. denticola protein a (tdpa). complete sequence determination revealed an open reading fram ...19912037356
isolation and characterization of a plasmid from treponema denticola.agarose gel electrophoresis of whole genomic dna of the oral spirochaete treponema denticola has revealed a plasmid-like fraction. purification and restriction enzyme analysis has confirmed the presence of a 2.6-kb circular plasmid, which has been mapped for restriction sites and cloned into the escherichia coli plasmid puc18. southern blot analysis of genomic t. denticola dna, using the plasmid as a probe, has shown that the plasmid is present only as an extra-chromosomal element. no plasmid-co ...19912040428
multivariate analyses of cellular fatty acids and carbohydrates of 1:2:1 and 2:4:2 spirochetes.delimitation of small-sized spirochetes of the oral cavity can be difficult. the endoflagella pattern has long served as the main criterion for taxonomic distinction. for approved species, e.g. treponema denticola, several endoflagella patterns are observed, which indicates that this criterion is inadequate. the present study with gc and gc-ms used fatty acids and carbohydrates of whole-cell methanolysates to distinguish 1:2:1 and 2:4:2 subgingival spirochetes. thirteen fatty acids: c12:0, c13:0 ...19912054175
detection of two anaerobic periodontopathogens in children by means of the bana and elisa assays.the mouths of young children become colonized by a variety of bacteria, but there have been only a few studies that have sought the presence of periodontopathic species in this population. almost all of these studies used culturing techniques rather than the newer detection methodologies for various periodontopathogens. studies in adults have shown that treponema denticola and porphyromonas (bacteroides) gingivalis can be detected in dental plaque by use of the bana and elisa diagnostic tests. i ...19912066486
comparison of the benzoyl-dl-arginine-naphthylamide (bana) test, dna probes, and immunological reagents for ability to detect anaerobic periodontal infections due to porphyromonas gingivalis, treponema denticola, and bacteroides forsythus.most forms of periodontal disease are associated with the presence or overgrowth of anaerobic species that could include treponema denticola, porphyromonas gingivalis, and bacteroides forsythus among others. these three organisms are among the few cultivable plaque species that can hydrolyze the synthetic trypsin substrate benzoyl-dl-arginine-naphthylamide (bana). in turn, bana hydrolysis by the plaque can be associated with periodontal morbidity and with the presence of these three bana-positiv ...19921311335
a sensitive enzymatic method (sk-013) for detection and quantification of specific periodontopathogens.porphyromonas gingivalis, bacteroides forsythus, and treponema denticola have been found to predominate in periodontal pockets of patients with adult periodontitis. these microorganisms hydrolyze the synthetic peptide n-benzoyl-dl-arginine-2-naphthylamide (bana). in this study, we developed an enzymatic method, designated sk-013, to detect the existence of these microorganisms in subgingival plaque bacteria. this enzymatic method was based on the observation of the hydrolysis of n-carbobenzoxy-g ...19921312591
a sensitive enzymatic method (sk-013) for detection of treponema denticola, porphyromonas gingivals and bacteroides forsythus in subgingival plaque samples.an enzymatic method, sk-013, was developed for rapid detection of the peptidase activity in subgingival plaque samples. this method was found to have specificity for porphyromonas gingivalis, treponema denticola, bacteroides forsythus, and some capnocytophaga strains. the purpose of this study was to determine whether sk-013 could indicate the presence of periodontopathic bacteria, including t. denticola, p. gingivalis and b. forsythus, which produce trypsin-like enzymes. subgingival plaque samp ...19921312592
treponema denticola and porphyromonas gingivalis as prognostic markers following periodontal treatment.subgingival plaque samples were collected from individuals with advanced periodontitis before and 3 to 11 weeks after scaling and root planing periodontal treatment. the plaque levels of treponema denticola and porphyromonas gingivalis antigens were measured before and after treatment by a quantitative immunoassay procedure using monoclonal antibodies specific for these oral bacteria. a decrease in mean levels of t. denticola (p less than .05) and p. gingivalis antigens (p less than .09) were ob ...19921315388
purification and substrate specificity of an endopeptidase from the human oral spirochete treponema denticola atcc 35405, active on furylacryloyl-leu-gly-pro-ala and bradykinin.an endopeptidase was purified to homogeneity from the cell extracts of treponema denticola atcc 35405 (a human oral spirochete) by a procedure that comprised dialysis, anion exchange fast protein liquid chromatography (fplc), hydroxylapatite fplc, immobilized metal affinity fplc, fplc chromatofocusing, and two consecutive gel permeation fplc steps. the enzyme is a 62-kda protein with an isoelectric point of 6.5-7.0. experiments with enzyme inhibitors suggest that this enzyme is a metallopeptidas ...19921321141
inhibition of peptidase and glycosidase activities of porphyromonas gingivalis, bacteroides intermedius and treponema denticola by plant extracts.aqueous extracts from 5 plants used widely in kenya as chewing sticks (mswaki) for the control of oral hygiene were tested for their ability to inhibit extracellular peptidase and glycosidase enzyme activities produced by the periodontopathic bacteria porphyromonas gingivalis (formerly bacteroides gingivalis), bacteroides intermedius and treponema denticola. the plants studied were rhus natalensis, cupressus hisitanica, sida cordifolia, olea africana and euclea divinorum. protease activities, in ...19921325483
bacterial synergy of treponema denticola and porphyromonas gingivalis in a multinational population.treponema denticola and porphyromonas gingivalis have been associated with human adult severe periodontitis. in this study, we quantified these putative pathogens in subgingival plaque samples collected from 74 fijians, 74 colombians and 73 u.s. americans stationed at the multinational force and observers encampment in the sinai desert, egypt. a contingency table of t. denticola and p. gingivalis frequency revealed a highly significant synergistic relationship. we discovered that the occurrence ...19921326739
nutritional interactions between two suspected periodontopathogens, treponema denticola and porphyromonas gingivalis.a mutual symbiotic enhancement of growth of porphyromonas gingivalis and treponema denticola is described in this report. brain heart infusion broth supplemented with vitamin k did not support the individual growth of p. gingivalis or t. denticola. however, when inoculated as a mixture, both bacterial species did grow significantly. the growth-stimulating factors produced by p. gingivalis and t. denticola were dialyzable and heat stable and were further identified as isobutyric acid and succinic ...19921333450
demonstration of a bimodal coaggregation reaction between porphyromonas gingivalis and treponema denticola.this study demonstrates a strong coaggregation reaction between 2 suspected periodontopathogens: porphyromonas gingivalis and treponema denticola. other black-pigmented oral bacterial species tested did not coaggregate with t. denticola. this specific interbacterial aggregation was bimodal, since heating of both cell types was required to completely eliminate the reaction. the coaggregation reaction occurred between ph 4 and 9. under some conditions, arginine and d-galactosamine were effective i ...19921337373
homology of a plasmid from the spirochete treponema denticola with the single-stranded dna plasmids.the 2,647-bp nucleotide sequence of cryptic plasmid ptd1, isolated from the oral spirochete treponema denticola, was determined. the sequence revealed two open reading frames, a and b, which encode polypeptides of 335 and 235 amino acids, respectively. open reading frame a shows sequence similarity to genes that encode replication proteins from a group of plasmids common in gram-positive bacteria, which replicate via a single-stranded intermediate.19921339420
relative proportions of pathogen-related oral spirochetes (pros) and treponema denticola in supragingival and subgingival plaque from patients with periodontitis.the purpose of this study was to use monoclonal antibodies to enumerate spirochetes in dental plaque, including the newly recognized pathogen-related oral spirochete (pros) and specific serovars of treponema denticola. plaque was collected from control subjects with no apparent periodontal disease and from sites of moderate to severe chronic periodontitis in patients with inflammatory periodontal disease. individual monoclonal antibodies were used to determine whether spirochetes were present an ...19921372653
identification of proteases from periodontopathogenic bacteria as activators of latent human neutrophil and fibroblast-type interstitial collagenases.activation of latent human fibroblast-type and neutrophil interstitial procollagenases as well as degradation of native type i collagen by supra- and subgingival dental plaque extracts, an 80-kda trypsinlike protease from porphyromas gingivalis (atcc 33277), a 95-kda chymotrypsinlike protease from treponema denticola (atcc 29522), and selected bacterial species commonly isolated in periodontitis was studied. the bacteria included were prevotella intermedia (atcc 25261), prevotella buccae (es 57) ...19921398963
polymerase chain reaction for detection of leptospira spp. in clinical samples.a sensitive assay for leptospira spp., the causative agent of leptospirosis, was developed on the basis of the polymerase chain reaction (pcr). a 331-bp sequence from the leptospira interrogans serovar canicola rrs (16s) gene was amplified, and the pcr products were analyzed by dna-dna hybridization by using a 289-bp fragment internal to the amplified dna. specific pcr products also were obtained with dna from the closely related nonpathogenic leptospira biflexa but not with dna from other spiro ...19921400983
growth of porphyromonas gingivalis, treponema denticola, t. pectinovorum, t. socranskii, and t. vincentii in a chemically defined medium.a chemically defined medium, omiz (oral microbiology and immunology, zürich)-w1 was developed. medium omiz-w1 supports the long-term proliferation of a wide range of oral anaerobes, including representative strains of four treponema species and porphyromonas gingivalis. high concentrations of ascorbic acid and ammonium ions proved to be important for the growth of these organisms. t. denticola cd-1 grew in the absence of polyamines and long-chain fatty acids, t. pectinovorum and t. socranskii re ...19921400984
cell-bound peptidase activities of treponema denticola atcc 33520 in continuous culture.the oral spirochaete treponema denticola atcc 33520 was grown at a mean generation time of 10 h in anaerobic continuous culture in a serum- and carbohydrate-free medium at ph 7.0. the extracellular proteolytic activities of this spirochaete were then investigated by incubating washed cells with 68 2-naphthylamide derivatives of the extended api system. chymotrypsin-like, trypsin-like, elastase-like and iminopeptidase activities were demonstrated. the phenylalanine peptidase or chymotrypsin-like ...19921402787
cloning and expression of the aspartate carbamoyltransferase gene from treponema denticola.treponema denticola seems to play a central role in the etiology of human periodontal disease. we have cloned an antigenic protein-coding sequence from t. denticola atcc 33520. the protein-coding region was found to be a 3-kbp hindiii-hindiii fragment. the open reading frame consists of 1,426 bp and codes for a protein with an m(r) of 54,919. the deduced amino acid sequence showed 33.8% homology with that of the aspartate carbamoyltransferase of escherichia coli. the gene products showed asparta ...19921444372
extrachromosomal elements of spirochetes.the spirochetes include some important pathogenic bacteria, treponema, borrelia and leptospira. the pathogeneses of these spirochetes are very diverse. in an attempt to learn more about the virulence factors among the spirochetes, their genetic organization and capacity have been studied. structural analysis of the genome in borrelia has shown that the genome is composed of one linear maxi-chromosome with additional linear minichromosomes as well as several supercoiled circular plasmids. moreove ...19921475522
the collagenolytic activity of treponema denticola. 19921480016
comparison of various detection methods for periodontopathic bacteria: can culture be considered the primary reference standard?the development of diagnostic tests for a periodontal infection raises the issue as to what the appropriate reference standard, or "gold standard," should be for the evaluation of a new test. the present research was initiated to compare the ability of several detection methods, i.e., a serial dilution anaerobic culture and/or microscopic procedure, a dna probe procedure, and immunological reagents using both an enzyme-linked immunosorbent assay and an indirect immunofluorescence assay to detect ...19921537912
hemagglutination activity of treponema denticola grown in serum-free medium in continuous culture.hemagglutination by different treponema denticola strains was observed for erythrocytes of human, horse, bovine, and rabbit origin. the growth of t. denticola atcc 33520 in serum-free medium in continuous culture enabled us to study the hemagglutinating activity of freshly harvested spirochetes of a defined physiological status. the hemagglutinating activity was cell bound and not related to motility or appendages, such as fimbriae. the activity was destroyed by proteolytic enzymes, heat, and al ...19921563762
characterization, cloning, and binding properties of the major 53-kilodalton treponema denticola surface antigen.treponema denticola surface proteins were studied for their biochemical and biological characteristics. sodium dodecyl sulfate-polyacrylamide gel electrophoresis (sds-page) analysis of detergent extracts of whole cells revealed a major protein of 53 kda and a number of minor proteins. antiserum raised against whole cells of t. denticola atcc 35405 reacted with the 53-kda protein and a 72-kda protein but not with the other proteins. immunoelectron microscopy with anti-53-kda-protein antibodies sh ...19921563796
treponema denticola induces actin rearrangement and detachment of human gingival fibroblasts.spirochetes are associated with destructive periodontal diseases, and one cultivatable oral species, treponema denticola, binds to mammalian cells and perturbs metabolism. to evaluate the cytoskeletal responses and attachment functions of human gingival fibroblasts (hgf) exposed to t. denticola, monolayers of hgf were incubated with t. denticola strains atcc 35405, e, and e' in serum-free medium. hgf retracted pseudopods, rounded up, and ultimately detached from the substratum. scanning electron ...19921639504
morphology and dynamics of protruding spirochete periplasmic flagella.we recently characterized the three-dimensional shape of treponema phagedenis periplasmic flagella (pfs). in the course of these studies, we observed protrusions on swimming cells that resembled pfs. here we present a detailed characterization of the shape, structure, and motion of these protrusions. although protrusion formation occurred primarily in wild-type cells during the stationary phase, a large fraction of exponential-phase cells of cell cylinder helicity mutants (greater than 90% of mu ...19921732217
[identification of bacteria using dna probes].since the microbial specificity of periodontal diseases is well established, having a valid microbial diagnostic test is essential for a correct and a coherent treatment planning. dna probe will be used to identify and quantify the oral pathogens, most commonly associated with periodontitis. this test utilizes innovative dna probe technology to identify unique segments of dna in each of the following bacteria: bacteroides gingivalis, bacteroides intermedius, actinobacillus actinomycetemcomitans, ...199212051174
pore-forming properties of the major 53-kilodalton surface antigen from the outer sheath of treponema denticola.a 53-kda protein from the outer sheath of the oral spirochete treponema denticola was purified to homogeneity and shown to reconstitute channels in black lipid bilayer model membranes. the channel had a single-channel conductance of 1.8 ns in 0.1 m kcl, making this the largest porin channel observed to date (estimated diameter, 3.4 nm). electron micrographs of 53-kda-protein-containing outer sheaths of t. denticola showed a regular hexagonal array of darker staining pits.19937682993
cytotoxic effect of peptidoglycan from treponema denticola.peptidoglycan isolated from pathogenic bacteria has been previously found to exhibit various biological activities. the aim of this investigation was to evaluate the toxicity of treponema denticola peptidoglycan towards epithelial cells. the cytotoxicity of a lipopolysaccharide-like material was also determined. epithelial cells were incubated with the test substances and cell viability was assayed by measuring lactate dehydrogenase activity and the conversion of tetrazolium salt into blue forma ...19938015419
development of quasi-multicellular bodies of treponema denticola.the formation of quasi-multicellular bodies of treponema denticola was analysed using different electron microscopical methods. these bacteria could develop four different conformations: (i) normal helical forms; (ii) twisted spirochetes, forming plaits; (iii) twisted spirochetes,forming club-like structures; (iv) spherical bodies in different size. treponemes within spherical bodies, plaits, and clubs proved to be enclosed in a common outer sheath in which the normal arrangement of their axial ...19938215797
configural frequency analysis for exploring bacterial sets in periodontal health and disease.periodontal research has been concerned with identifying bacterial sets in oral health and disease. configural frequency analysis (cfa) is a taxonomical method used to test the statistical significance of patterns of elementary cell frequencies in cross-tabulated data, and may therefore be used to evaluate interactions among occurrences and non-occurrences of periodontal microorganisms. cfa patterns may exist as configural types or anti-types depending on whether observed cell frequencies are gr ...19938222602
the effects of incubation length and temperature on the specificity and sensitivity of the bana (n-benzoyl-dl-arginine-naphthylamide) test.a previous multi-center study examining patients diagnosed as having at least four periodontally diseased teeth showed that when bana (n-benzoyl-dl-arginine-naphthylamide) hydrolysis by periodontal pathogens such as treponema denticola, porphyromonas gingivalis, and bacteroides forsythus was evaluated versus clinical parameters such as clinical judgment of disease, bleeding on probing, and pocket depth, the sensitivity of the test was 84%, 82%, and 87%, respectively, while the specificity was on ...19938229620
phosphorylated nutrient uptake by treponema denticola and other potential periodontopathogens.nutrient uptake may contribute to the survival of certain potential periodontopathogens in the competitive environment of the gingival sulcus. this study was conducted to assess the uptake of commercially available, key radiolabelled phosphorylated compounds by treponema denticola. there was a linear relationship in the uptake of atp and g-1-p with cell concentrations of 0.1-2.5 mg of cell dry weight. this uptake reached a steady state within 15 min, and at temperatures of 25-37 degrees c the up ...19938229676
involvement of treponemal surface-located protein and carbohydrate moieties in the attachment of treponema denticola atcc 33520 to cultured rat palatal epithelial cells.we studied the nature of attachment of treponema denticola atcc 33520 to a microscopically distinct population of rounded rat palatal epithelial cells. the motility of the freshly harvested spirochetes appeared not be a prerequisite for attachment. treatment of t. denticola atcc 3350 with proteinase-k, heat, glutaraldehyde, formaldehyde and periodate oxidation decreased the attachment to the rounded rat palatal epithelial cells, indicating the involvement of protein and carbohydrate moieties. tr ...19938247611
viscosity-dependent locomotion of oral spirochetes.spirochetes are thought to remain motile in environments (such as intercellular spaces) that immobilize extracellularly flagellated eubacteria. this attribute suggests that the viscosity of the milieu is of importance to locomotion. we sought to determine the interdependence of oral spirochete locomotion with media viscosity. video time-lapse microscopy using darkfield optics was used. the motility of the spirochetes in media of different viscosities (various concentrations of noble agar) was me ...19938247612
binding of hemin and congo red by oral hemolytic spirochetes.colony-forming units or cells in suspension of oral anaerobic spirochetes (treponema denticola, treponema vincentii and treponema socranskii) bind hemin and congo red. hemin or congo red binds to a hydrophobic polypeptide receptor that is located in the outer membrane of the bacterial cells and it has a relative molecular mass of 47 kda. these oral spirochetes also lyse sheep erythrocytes to produce beta-hemolytic zones around colony-forming units. the oral spirochetes may acquire iron for growt ...19938247613
proteolytic and oxidoreductase activity of treponema denticola atcc 35405 grown in an aerobic and anaerobic gaseous environment.the cells of a human oral spirochete, treponema denticola atcc 35405, and of seven clinical isolates of this organism obtained from the subgingival dental plaque of periodontitis patients were studied for their ability to grow in an aerobic and an anaerobic environment, and for their profile of peptidohydrolase and oxidoreductase enzymes. the growth yield of aerobically grown cultures was either comparable to or higher than that of anaerobically grown ones regardless of whether prereduced broth, ...19938248625
fatty acid profiles of the outer membrane of atcc strains 35405, 35404 and 33521 of treponema denticola.the fatty acid composition of the outer membrane (outer sheath) of treponema denticola is not known. this study examined the fatty acid profiles of the outer membranes of t. denticola atcc strains 35405, 35404, 33521. homogeneous outer membranes were prepared from the three strains of t. denticola. the fatty acids were extracted and converted to methyl esters, and their mass spectra were determined with a sensitive hewlett-packard 5880a-5970 gas chromatography-mass spectrometry system. fatty aci ...19938254455
common and specific antigens of several treponemes detected by polyclonal antisera against major cellular proteins.thirteen polypeptide antigens with molecular weights ranging from 34 kda to 83 kda were selected and their antigenic behaviors and distribution were examined in 12 strains of microorganisms including treponema, borrelia, leptospira and leptonema. immunoblot analysis demonstrated that 45 kda and 83 kda polypeptides of treponema socranskii subsp. buccale atcc 35534, 53 kda antigen of treponema denticola atcc 33520 and 44 kda polypeptide of the strain g7201 were strain-specific. the 34, 62, 66 and ...19938265202
dna probe detection of periodontopathogens in advanced periodontitis.species-specific dna probes were used to determine the presence of actinobacillus actinomycetemcomitans (a.a.), porphyromonas (bacteroides) gingivalis, prevotella intermedia, treponema denticola, eikenella corrodens, fusobacterium nucleatum, and wolinella recta in subgingival plaque from deep pockets/sites of patients with advanced periodontitis. the subjects were 20 patients with severe adult periodontitis, 13 men and 7 women (mean age 45.6 +/- 6.7 yr). for each subject, 9-10 subgingival sites ...19938290878
bacterial mediators in periodontal disease.periodontal disease is the general description given to the inflammatory response of the gingiva and underlying connective tissue to bacterial accumulations (dental plaque) on the teeth. a limited number of cultivable species are usually associated with periodontal disease. the majority of putative periodontal pathogens are gram-negative anaerobic rods. some of the characteristics of actinobacillus actinomycetemcomitans, porphyromonas gingivalis, and treponema denticola will be discussed, given ...19938324120
effect of outer membrane of treponema denticola on bone resorption.the effect of the outer membrane (outer sheath) of treponema denticola on bone resorption was studied. bone resorption was measured by the release of previously incorporated 45ca from the shafts of the radii and ulnae of 19-day fetal rats. a treated-over-control ratio (t/c ratio) significantly greater than 1 indicated the stimulation of bone resorption by the test substance. the addition of outer membrane of t. denticola increased the release of 45ca from the assay bones. the minimum concentrati ...19938355985
a successful method for quantifying viable oral anaerobic spirochetes.spirochetes are markedly prevalent in periodontal disease but are not included as predominant cultivable organisms because of the inability to quantify them by viable count. a successful method was developed for enumerating viable oral spirochetes as colony-forming units (cfu) in an agarose-based medium. treponema denticola, treponema vincentii and treponema socranskii in log-phase growth in new oral spirochete (nos) broth were used for evaluation of the method. critical components of the method ...19938355989
attachment of treponema denticola strains to monolayers of epithelial cells of different origin.the attachment of 10 different treponema denticola strains to monolayers of 4 types of epithelial cells derived from rat palatal epithelium, guinea pig ear, human buccal epithelium and human corneal epithelium was screened microscopically. most t. denticola strains were able to attach to all four types of epithelial cells. the t. denticola strains seemed to attach better to epithelial cells derived from primary cultured material. the t. denticola strains showed different degrees of attachment. s ...19938355990
stimulation of in vitro growth of treponema denticola by extracellular growth factors produced by porphyromonas gingivalis.cell-free culture filtrates of porphyromonas gingivalis grown in wilkins-chalgren broth stimulated the growth of six strains of treponema denticola in 1186 broth when compared with the effect of uninoculated wc. the ph of the 1186 broth was not altered by the addition of either culture filtrate or wc, and all media were fully reduced prior to inoculation with t. denticola. growth was also stimulated by factors precipitated from the culture filtrate with 90% (nh4)2so4, 50% cold ethanol, or 50% co ...19938388413
prevalence of treponema denticola and porphyromonas gingivalis in plaque from periodontally-healthy and periodontally-diseased sites.intracrevicular plaque from periodontally-healthy individuals who had refrained from oral hygiene measures for 24 h prior to sampling, and subgingival plaque from diseased sites of patients with chronic periodontitis were screened by elisa for the presence of porphyromonas gingivalis and treponema denticola. the samples were also subjected to the perioscan test to detect the presence of enzymes capable of degrading n-benzoyl-dl-arginine-2-naphthylamide (bana). of the 141 samples from periodontal ...19938389879
the effect of incubation temperature on the specificity of the bana (n-benzoyl-dl-arginine-naphthylamide) test.the hydrolysis of bana by subgingival plaque samples is associated with the presence of either treponema denticola, porphyromonas gingivalis, and/or bacteroides forsythus. a protocol in which pure cultures were incubated for 15 min at 55 degrees c detected about 5 x 10(5) cfu of p. gingivalis and 1 x 10(6) cfu of t. denticola. clinical studies indicated that the bana test in this configuration will detect about 10(4) organisms in vivo as compared with the 10(5) to 10(6) organisms found with in v ...19938390044
measurement of electrical bioimpedance for studying utilization of amino acids and peptides by porphyromonas gingivalis, fusobacterium nucleatum, and treponema denticola.the growth response of porphyromonas gingivalis, fusobacterium nucleatum, and treponema denticola to peptides (supplied as trypticase) and amino acids (supplied as casamino acids) was measured over 24 hours by monitoring changes in alternating-current conductivity at 37 degrees c. all species utilized peptides preferentially over amino acids. these results are consistent with those obtained previously with conventional growth-response experiments. the duration of the linear growth response to tr ...19938391864
the effects of acacia arabica gum on the in vitro growth and protease activities of periodontopathic bacteria.the antibacterial activity of acacia gum was assessed using fresh isolates and reference strains of actinobacillus actinomycetemcomitans, capnocytophaga spp., porphyromonas gingivalis, prevotella intermedia and treponema denticola. a fine aqueous suspension of gum was produced by sonication and then a soluble fraction isolated by centrifugation and membrane filtration. these preparations were incorporated into columbia agar at doubling concentrations. growth of p. gingivalis and p. intermedia cu ...19938473532
fibronectin-binding proteins of a human oral spirochete treponema denticola.major polypeptides from a human oral spirochete treponema denticola atcc 33520 were examined to demonstrate their ability to bind to human plasma fibronectin by immunoblot analysis. of three main polypeptides separated on sodium dodecyl sulfate polyacrylamide gels 53,000-daltons (53-kda) and 72-kda surface antigenic proteins and a 38-kda axial flagellar protein showed the ability to bind to fibronectin, suggesting that fibronectin on host cells can mediate cytoadherence of t. denticola by its bi ...19938474361
treponema denticola (ex brumpt 1925) sp. nov., nom. rev., and identification of new spirochete isolates from periodontal pockets.standard growth and isolation methods were used to obtain five new treponema strains in pure culture from deep periodontal pockets. the strains were identified to the species level by various methods, including agglutination, immunofluorescence, a dot blot immunoassay, electron microscopy, gas-liquid chromatography of metabolic volatile fatty acids, and dna hybridization. two isolates were strains of treponema socranskii; the other three were strains of "treponema denticola," a species described ...19938494734
characterization of the wheat germ agglutinin-binding property of treponema denticola.lectins were used to characterize glycoconjugates on the cell surface of treponema denticola, a suspected periodontopathogen. bacteria were first screened by light microscopy using fluorescein isothiocyanate-coupled lectins. wheat germ agglutinin (wga) showed a high reactivity to t. denticola. while the wga-binding activity was accentuated following heating or detergent treatments of bacterial cells, the reaction was inhibited by incorporation of competing carbohydrates. scanning and transmissio ...19938496784
antigenic behaviors of two axial flagellar proteins detected in treponema denticola.two polypeptide antigens with molecular sizes of 34,000 daltons (34 kda) and 38 kda were separated from heated cells of a human clinical treponeme strain g7201 and treponema denticola atcc 35404, respectively. the rabbit polyclonal antisera against these antigens were produced and examined for their immunological reactions with the two heated antigens or intact spirochetal cells. immunoblot analysis showed that the 34-kda protein was also detected in t. denticola atcc 35404 and atcc 33520, and t ...19938502179
antimicrobial action of axol on periodontopathic bacteria.the antimicrobial action of axol was tested against a panel of periodontopathic bacteria, which included treponema denticola, treponema vincentii, treponema sp., porphyromonas gingivalis, prevotella intermedia, prevotella melaninogenica, and fusobacterium nucleatum. the axol commercial solution (undiluted) was effective in inhibiting some of the bacteria but not all. the rational for the use of antimicrobials is discussed.19938180485
clustering of fibronectin adhesins toward treponema denticola tips upon contact with immobilized fibronectin.treponema denticola has been shown to bind to immobilized fibronectin (fn) by its tips. yet labeling of cells in suspension with an fn-gold conjugate to localize the fn adhesins shows that they are distributed in patches along the entire cell length. subsequent experiments have shown that the number and proportion of tip-oriented cells increase with time, suggesting that fn contact stimulates t. denticola to rearrange adhesins toward its tips. to test this hypothesis, t. denticola cells were all ...19948188343
effect of proteolytic enzymes on the lysis and growth of oral bacteria.previous studies have shown increased levels of proteolytic enzymes in affected periodontal sites. the aim of the present investigation was to evaluate the effect of proteolytic environments on the lysis and growth of selected oral bacteria associated with either healthy or diseased periodontal sites. the effect of trypsin, chymotrypsin and proteinase k on cell lysis was determined following incubation with bacteria, whereas the effect of the same proteolytic enzymes on bacterial growth was test ...19947478762
bacteriological diagnosis of periodontal disease.dental plaque bacteria cause virtually all the forms of inflammatory periodontal disease. periodontitis is caused by the specific periodontopathic bacteria, which induce destruction of connective tissue attachment and adjacent alveolar bone. examinations to identify the infections by porphyromonas gingivalis, actinobacillus actinomycetemcomitans, prevotella intermedia, campylobacter rectus, bacteroides forsythus, fusobacterium nucleatum, eikenella corrodens and treponema denticola have recently ...19948620588
coaggregation between porphyromonas gingivalis and treponema denticola.to elucidate an ecological profile of several periodontopathogens, the authors examined the coaggregation between cells of porphyromonas gingivalis and oral bacterial strains including treponema denticola in vitro. coaggregation between cells of plaque bacteria was examined by visual assay and phase-contrast microscope. p. gingivalis cells coaggregated with strains of t. denticola and treponema socranskii subspecies socranskii, but did not coaggregate with t. socranskii subspecies buccale, t. so ...19948689730
effect of initial therapy on dynamics of immunogloblin g levels to some periodontopathic bacteria in serum and gingival crevicular fluid.using enzyme-linked immunosorbent assay, the igg antibody levels to specific gram-negative periodontopathic bacteria in serum of 21 adult periodontitis patients and the gingival crevicular fluid (gcf) from 42 sites with destructive lesions and 21 healthy sites were evaluated before and after initial preparation. porphyromonas gingivalis, bacteroides forsythus, prevotella intermedia, prevotella nigrescens, campylobacter rectus, treponema denticola and actinobacillus actinomycetemcomitans in subgi ...19948689734
outer membrane antigens of oral treponema species.outer membrane (om) antigens of several oral treponemes were studied. sds-page revealed a 56-58-kda protein as a major component of isolated om vesicles. immunoblot analysis with eluted antibodies prepared from treponema denticola atcc 33520 recognised the 56-58-kda protein, which was highly conserved in the 17 t. denticola strains tested. the protein was also a component of a t. denticola desoxycholate-extractable, ethanol-soluble antigen (des-ag) but was not present in t. pectinovorum or t. vi ...19948289216
cloning and sequence analysis of a chymotrypsinlike protease from treponema denticola.a clone expressing a treponema denticola chymotrypsinlike protease from recombinant plasmid psa2 was identified in a genomic library of t. denticola atcc 35405. nucleotide sequencing of the insert identified an open reading frame, designated the prtb gene, which codes for the protease. two potential inverted repeat sequences are present both upstream and downstream from the prtb gene. the prtb gene would code for a putative protein of 273 amino acids with a calculated molecular mass of 30.4 kda ...19948039913
characterization of hemolysis and hemoxidation activities by treponema denticola.this study determined the presence of two hemolytic activities in the oral treponeme, treponema denticola, strains atcc 35404 (td-4), atcc 33520, gm-1, and ms25. these activities, referred to as hemolytic and hemoxidative (hea, heo, respectively), were found to be both secreted into the extracellular environment, and cell associated. the extracellular activity was associated with small molecules with relative molecular weights of < 1000 da, and its activity was cysteine independent; the cell-ass ...19948090077
purification and characterization of a 45 kda hemolysin from treponema denticola atcc 35404.a 45 kda polypeptide capable of erythrocyte (rbc) lysis and hemoglobin oxidation was isolated from treponema denticola, atcc 35404 (td-4) after sequential ammonium sulfate (2.8-3.6 m) precipitation and preparative electrophoresis. the purified polypeptide produced a single protein band on page at a relative molecular weight of 45 kda in the presence and absence of sds. the polypeptide was sensitive to proteinase k and pronase, and heating at 80 degrees c. the protease inhibitors, pmsf, tlck and ...19948090078
isolation and characterization of a 53 kda major cell envelope protein antigen from treponema denticola atcc 35405.a major cell envelope protein was purified from the cell envelope fraction of treponema denticola atcc 35405 by ion exchange chromatography after extraction with zwittergent 3-14. sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed a relative molecular mass of 53 kda for this protein with a pi of 6.3-6.8. amino acid analysis revealed that this protein contained high proportions of hydrophobic amino acids (40.4%), and no cysteine could be detected. the n-terminus of the protein was b ...19948113954
similarity between the 38-kilodalton lipoprotein of treponema pallidum and the glucose/galactose-binding (mglb) protein of escherichia coli.the recent discovery that abundant and immunogenic lipoproteins constitute the integral membrane proteins of treponema pallidum has prompted efforts to investigate their importance in the physiology and ultrastructure of the organism and in immune responses during infection. earlier studies identified a 38-kda lipoprotein of t. pallidum believed to be specific to the pathogen. in the present study, monoclonal antibodies generated against the 38-kda lipoprotein of t. pallidum reacted with cognate ...19948132345
detection of porphyromonas gingivalis in gingival exudate by a dipeptide-enhanced trypsin-like activity.porphyromonas gingivalis in subgingival plaque is an important risk factor for future periodontal attachment loss in susceptible adults. the elimination of p. gingivalis is usually concomitant with a healing process. therefore, it should be valuable to have an easy chairside method to follow the effect of periodontal treatment on p. gingivalis detection as well as on its eventual reappearance during the maintenance period. we have previously reported the stimulation of amidolytic activity of p. ...19948133415
characterization of antisera raised against treponema denticola (atcc 33521) whole cell, outer sheath, protoplasmic cylinder, and axial flagella.in this study we produced polyclonal antisera directed to whole cell, outer sheath, protoplasmic cylinder and axial flagella sonicates of treponema denticola (atcc 33521) reference strain. furthermore, the reactivity of the antisera was determined, using the enzyme-linked immunosorbent assay and immunoblotting techniques. as control antigen, other gram-negative bacteria (salmonella minnesota, escherichia coli) and related pathogenic spirochetes (borrelia burgdorferi and treponema pallidum) were ...19948167426
characterization of fibrinolytic activities of treponema denticola.several fibrinolytic activities of treponema denticola, an oral spirochete associated with gingivitis and periodontal disease, were identified and characterized following phase partitioning with the nonionic detergent triton x-114. the apparent molecular masses of the proteases ranged from 91 to 228 kda when analyzed in sodium dodecyl sulfate-polyacrylamide gels containing fibrinogen as the protease substrate. a qualitative analysis of zymograms showed that the proteases were highly enriched in ...19948168936
diversity of cultivable and uncultivable oral spirochetes from a patient with severe destructive periodontitis.to determine the genetic diversity of cultivable and uncultivable spirochetes in the gingival crevice of a patient with severe periodontitis, partial 16s rrna genes were cloned from pcr-amplified products of dna and rna extracted from a subgingival plaque sample. approximately 500 bp were amplified in pcrs by using universally conserved primers with polylinker tails. purified pcr products were cloned into escherichia coli by using the plasmid vector puc19. the resultant clone library was screene ...19948168954
homology among treponema denticola plasmids.three of 16 isolates of treponema denticola were found to contain small (2.0-2.7 kb) cryptic plasmids. these were ptd1 from t. denticola atcc 33520, ptd2 from strain t32a, and ptd3 from strain d3a1. these plasmids were characterized by restriction mapping and cloned into e. coli plasmid puc19. extensive homology between these plasmids was revealed by southern blot, and single-stranded dna regions were found by neutral southern blots and s1 nuclease mapping. these plasmids were not found in serov ...19947808774
effect of iron regulation on expression and hemin-binding function of outer-sheath proteins from treponema denticola.the effect of the iron-chelating compounds edda and bpd on polypeptide regulation in the putative oral pathogen treponema denticola was studied. sds-page analysis of the t. denticola strains grown in the presence of edda or bpd, i.e. iron-limiting environmental conditions, revealed the expression of 44 and 43 kda polypeptides in the outer sheath, a 73 kda polypeptide in the cell membrane, and a 16 kda polypeptide in the soluble cell fraction. the hemin-binding activity of purified outer sheaths ...19947815916
cloning and expression of hemolysin genes from treponema denticola strains atcc 35404 (td-4) and human clinical isolate gm-1 in escherichia coli.the oral spirochete, treponema denticola is a putative etiologic agent in adult periodontitis, and acute necrotizing ulcerative gingivitis. in vitro, the oral treponeme produces several factors including proteases, hemolysins, hemin-binding proteins, which could potentially be involved in the virulence of this spirochete. our laboratory has been investigating the pathobiology of t. denticola, and has demonstrated the production of several hemolysins by t. denticola. in this report two hemolysin ...19947815917
presence of treponema denticola and porphyromonas gingivalis in children correlated with periodontal disease of their parents.considerable evidence exists suggesting that periodontal disease is due to the overgrowth of a finite number of specific bacteria such as porphyromonas gingivalis, actinobacillus actinomycetemcomitans, treponema denticola, bacteroides forsythus, and prevotella intermedia, among others. three of these organisms-p. gingivalis, t. denticola, and b. forsythus-can be easily detected in plaque samples by the hydrolysis of the synthetic trypsin substrate benzoyl-dl-arginine-naphthylamide (bana). the ai ...19947929977
identification of lactoferrin-binding proteins from treponema pallidum subspecies pallidum and treponema denticola.lactoferrin-binding or -associated proteins were identified in treponema pallidum subspecies pallidum and treponema denticola by affinity column chromatography using human lactoferrin and detergent-solubilized, radiolabelled spirochaetes. two discrete polypeptides of t. pallidum with masses of 45 and 40 kda and a broad band from 29-34 kda exhibited association with human apo- and partially ferrated lactoferrin. t. denticola produced two proteins that associated with a lactoferrin affinity matrix ...19947934885
trypsin-like activity levels of treponema denticola and porphyromonas gingivalis in adults with periodontitis.treponema denticola (td) and porphyromonas gingivalis (pg) are associated with human moderate and severe adult periodontal diseases. this study quantifies these two anaerobes and their trypsin-like (tl) activities in subgingival plaque collected from both clinically healthy and periodontally diseased sites of human periodontitis patients. antigen levels of the microorganisms were determined by monoclonal antibodies and tl activities were measured by the fluorescent substrate z-gly-gly-arg-afc in ...19947989615
degradation of endogenous plasma membrane fibronectin concomitant with treponema denticola 35405 adhesion to gingival fibroblasts.treponema denticola adhesion and degradation of fibronectin (fn) on human gingival fibroblasts (hgf) were studied by immunofluorescence and enzyme-linked immunosorbent assays. the number of adherent bacteria increased and the amount of immunoreactive fn decreased as a function of increasing t. denticola concentration. the distribution of cell-bound fn was punctate in micrographs. anti-human fn impaired bacterial adhesion to hgf. phenylmethylsulfonyl fluoride inhibited fn degradation but not adhe ...19948005694
treponema denticola as a model for polar adhesion and cytopathogenicity of spirochetes.recent studies suggest that the tip-oriented adhesion of treponema denticola is a consequence of polar clustering of its adhesins on contact with the substratum and is compatible with viability. such adhesion to cells stimulates a host of cytoskeletal and volume regulatory changes. these studies may give insight into mechanisms of colonization and cytopathogenicity of other pathogenic spirochetes.19948012753
an endo-acting proline-specific oligopeptidase from treponema denticola atcc 35405: evidence of hydrolysis of human bioactive peptides.an endo-acting proline-specific oligopeptidase (prolyl oligopeptidase [popase], ec 3.4.21.26) was purified to homogeneity from the triton x-100 extracts of cells of treponema denticola atcc 35405 (a human oral spirochete) by a procedure that comprised five successive fast protein liquid chromatography steps. the popase is a cell-associated 75- to 77-kda protein with an isoelectric point of ca. 6.5. the enzyme hydrolyzed (optimum ph 6.5) the pro-pna bond in carbobenzoxy-gly-pro-p-nitroanilide (z- ...19947523301
cloning and expression of a neutral phosphatase gene from treponema denticola.we have isolated and characterized a neutral phosphatase gene, phon, from treponema denticola atcc 35405. the gene was isolated from a t. denticola clone bank constructed in the medium-copy-number plasmid vector pmcl19. subcloning and nucleotide sequencing of the dna insert from one phosphatase clone, ptph14, revealed that the activity corresponded to an open reading frame consisting of 1,027 bp coding for a 37.9-kda protein. hydrophobicity analysis indicated that the protein exhibits some hydro ...19957534273
induction of cytoskeletal rearrangements and loss of volume regulation in epithelial cells by treponema denticola.the early responses of oral epithelial cells to the adhesion of the oral spirochaete treponema denticola were studied as a model of microbial perturbation of the plasma membrane. kb cell (atcc ccl 17) monolayers were incubated with t. denticola (atcc 35405) in alpha-mem (minimal essential medium) for periods of 1-4 h at 37 degrees c without serum. control cultures were exposed to bacteria-conditioned alpha-mem without serum or bacteria or to alpha-mem alone. at the end of each incubation, detach ...19957541623
role of the chymotrypsin-like membrane-associated proteinase from treponema denticola atcc 35405 in inactivation of bioactive peptides.the ability of washed whole cells of treponema denticola atcc 35405 to hydrolyze (inactivate) substance p, bradykinin, and angiotensin i was studied. substance p was attacked primarily at the phe-8-gly-9 bond by a chymotrypsin-like proteinase (ctlp), at pro-4-gln-5 by an endo-acting prolyl oligopeptidase (popase), and at gln-5-gln-6 by an endopeptidase (falgpa-peptidase). bradykinin was cleaved at phe-5-ser-6 by the falgpa-peptidase and at pro-7-phe-8 by the popase. angiotensin i was rapidly con ...19957543886
ribotyping on small-sized spirochetes isolated from subgingival plaque.in the present study dna restriction patterns and corresponding ribotypes of 17 subgingival small-sized spirochetes (1:2:1 and 2:4:2 isolates), 2 treponema socranskii strains and two treponema denticola strains were examined. purified chromosomal dna was digested by bamhi, hindiii, psti and clai. the dna fragments were separated in a horizontal slab of 0.7% agarose containing ethidium bromide and transferred by nylon membranes. hybridization was carried out with digoxigenin-labelled copy dna of ...19957543994
detection of putative periodontal pathogens in subgingival specimens by 16s ribosomal dna amplification with the polymerase chain reaction.the utility of the 16s ribosomal rna-based polymerase chain reaction (pcr) for detection of actinobacillus actinomycetemcomitans, bacteroides forsythus, campylobacter rectus, eikenella corrodens, porphyromonas gingivalis, prevotella intermedia, and treponema denticola was examined and compared with that of anaerobic culture. primer pairs consisting of 20-27 nucleotides amplified 404- to 688-bp regions of 16s ribosomal rna genes of these organisms. this method had a lower detection limit of 50 ta ...19957548580
oligonucleotide probes to the 16s ribosomal rna: implications of sequence homology and secondary structure with particular reference to the oral species prevotella intermedia and prevotella nigrescens.eight oligonucleotides based upon regions of the small subunit 16s ribosomal rna gene sequences were analysed against a background of their position within the molecule and their two-dimensional structure to rationalise their use in recognising prevotella intermedia and prevotella nigrescens. the 41 clinical isolates from both oral and respiratory sites and two reference strains were subjected to dna-dna hybridisation and multilocus enzyme electrophoresis to confirm their identity. alignment of ...19957553378
proteases of treponema denticola outer sheath and extracellular vesicles.electron microscopical observations of the oral periodontopathogen treponema denticola show the presence of extracellular vesicles bound to the bacterial surface or free in the surrounding medium. extracellular vesicles from t. denticola atcc 35404, 50 to 100 nm in diameter, were isolated and further characterized. protein and proteolytic patterns of the vesicles were found to be very similar to those of isolated t. denticola outer sheaths. they were enriched with the major outer sheath polypept ...19957558307
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