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Oral Microbiology and Immunology Jun 1998Cumulative evidence indicates that bacterial adherence to mucosal and tooth surfaces as well as bacterial coaggregation are essential steps for colonization of various... (Review)
Review
Cumulative evidence indicates that bacterial adherence to mucosal and tooth surfaces as well as bacterial coaggregation are essential steps for colonization of various oral bacterial species. Bacterial fimbriae have been shown to play an important role in the interaction between bacteria and host cells or among bacterial cells. The properties of fimbriae from selected species of oral bacteria are discussed in terms of virulence traits and ecological significance. Among others, Porphyromonas gingivalis fimbriae have been most extensively studied. The fimbrial structure is composed of 41-kDa fimbrillin proteins. DNA sequencing of the fimbrillin gene (fimA) from nine strains of P. gingivalis suggests intraspecies variation in the structure of fimA, while retaining common immunochemical specificities. P. gingivalis fimbriae exhibit a wide variety of biological activities including immunogenicity, binding to various host proteins, stimulation of cytokine production and promotion of bone resorption, Actinobacillus actinomycetemcomitans also possesses fimbriae; however, little is known concerning their chemical, genetical, and biological properties. Fimbriae of Prevotella intermedia are shown to induce hemagglutination reaction, while those of Prevotella loescheii are found to cause coaggregation with other bacteria, i.e., Actinomyces viscosus and sanguis streptococci. Fimbriae from gram-positive oral bacteria such as oral Actinomyces and sanguis streptococci are described. These fimbriae may participate in coaggregation, binding to saliva-coated hydroxyapatite or glycoprotein of the surface layer of oral epithelial cells. Taken together, fimbriae are key components in cell-to-surface and cell-to-cell adherence of oral bacteria and pathogenesis of some oral and systemic diseases.
Topics: Actinomyces; Aggregatibacter actinomycetemcomitans; Bacterial Adhesion; Bacterial Proteins; Ecosystem; Fimbriae Proteins; Fimbriae, Bacterial; Mouth; Prevotella; Streptococcus; Virulence
PubMed: 10093527
DOI: 10.1111/j.1399-302x.1998.tb00724.x -
Journal of Medical Microbiology Jan 1999
Topics: Amputation, Surgical; Animals; Anti-Bacterial Agents; Bacteroidaceae Infections; Diabetes Mellitus, Type 2; Dogs; Foot Ulcer; Humans; Male; Middle Aged; Prevotella; Saliva
PubMed: 9920135
DOI: No ID Found -
Oral Microbiology and Immunology Dec 1998Thirty-one strains of 23 gram-negative oral bacterial species were examined for dextran-degrading activity on agar plates containing blue dextran. One strain each of... (Comparative Study)
Comparative Study
Thirty-one strains of 23 gram-negative oral bacterial species were examined for dextran-degrading activity on agar plates containing blue dextran. One strain each of Capnocytophaga ochracea, Capnocytophaga sputigena, Prevotella loescheii, Prevotella melaninogenica and Prevotella oralis had detectable dextranase activity. The culture supernatants of P. melaninogenica and P. oralis cells contained dextranases of multiple sizes, but those of the other three species had a single size of enzyme. A 56-kDa dextranase was purified from the culture supernatant of P. oralis and the antiserum against the enzyme was prepared with a rabbit. The Ouchterlony test showed that the antibody reacted with the supernatants of both P. melaninogenica and P. oralis but not with the others. Dot-blot hybridization using the dextranase gene of Streptococcus mutans as a probe revealed that there was no significantly homologous sequence in the chromosomal DNA of the five species.
Topics: Animals; Antigens, Bacterial; Bacterial Proteins; Dental Plaque; Dextranase; Electrophoresis, Polyacrylamide Gel; Gram-Negative Anaerobic Bacteria; Gram-Negative Facultatively Anaerobic Rods; Molecular Weight; Mouth; Rabbits; Sequence Homology, Nucleic Acid; Streptococcus mutans
PubMed: 9872116
DOI: 10.1111/j.1399-302x.1998.tb00696.x -
Oral Microbiology and Immunology Dec 1998Strains resembling Prevotella melaninogenica were isolated from healthy subjects and patients with periodontal disease and were identified using: a 5-test phenotypic...
Strains resembling Prevotella melaninogenica were isolated from healthy subjects and patients with periodontal disease and were identified using: a 5-test phenotypic screen; commercial identification kits; and a 16S rRNA-based polymerase chain reaction (PCR) method. Eleven clinical isolates closely resembling P. melaninogenica, and all from patients with periodontitis, were able to agglutinate erythrocytes. In the electron microscope, hemagglutinating isolates showed fimbria-like structures, that were not seen on non-hemagglutinating isolates. Some strains were further classified with PCR-restriction fragment-length polymorphism (RFLP) of 16S rRNA genes. Amplified 16S rDNA was digested using five different endonucleases, separated with agarose gel electrophoresis, stained and photographed. Photographs were then scanned, digitized and a distance matrix calculated using Dice coefficient, where the presence or absence of a band was used as a character. The distance matrix was plotted as a phenogram. At 70% similarity six clusters were seen. Type strains of separate Prevotella species did not fall into any cluster. Hemagglutinating isolates fell into three clusters: four clustered with the type strains of P. melaninogenica and Prevotella veroralis; four with other P. melaninogenica isolates and two hemagglutinating isolates clustered together Prevotella loescheii. The PCR-RFLP results showed that the hemagglutinating strains did not form a homogenous group inside the Prevotella genus.
Topics: Adult; Bacterial Typing Techniques; Fimbriae, Bacterial; Hemagglutination; Humans; Mouth; Periodontal Diseases; Polymerase Chain Reaction; Prevotella melaninogenica
PubMed: 9872112
DOI: 10.1111/j.1399-302x.1998.tb00692.x -
Current Microbiology Jan 1999The Prevotella loescheii adhesin gene, plaA, contains a coding gap between a small open reading frame (ORF-1) and a large open reading frame (ORF-2). Translation of the...
The Prevotella loescheii adhesin gene, plaA, contains a coding gap between a small open reading frame (ORF-1) and a large open reading frame (ORF-2). Translation of the plaA mRNA requires bypassing this 29-nt coding gap on the plaA transcript. We have determined the N-terminal peptide sequence of the SO34 adhesin beyond the gap sequence. This sequence shows that the peptide junction between ORF-1 and ORF-2 is continuous in the adhesin and supports the conclusion that synthesis of the SO34 adhesin occurs by a ribosomal hop mechanism. To elucidate upstream signals, we used the 5' RACE (rapid amplification of cDNA ends) technique to map the start point of the plaA mRNA. DNA sequencing of plasmids with the 5' RACE products placed the 5' end of plaA mRNA 270 nt upstream from the plaA start codon. A region corresponding to a Bacteroides fragilis promoter consensus sequence precedes this start site.
Topics: Adhesins, Bacterial; Amino Acid Sequence; Base Sequence; Genes, Bacterial; Lectins; Molecular Sequence Data; Polymerase Chain Reaction; Prevotella; Protein Biosynthesis; RNA, Messenger; Sequence Alignment; Transcription, Genetic
PubMed: 9841777
DOI: 10.1007/pl00006766 -
Roumanian Archives of Microbiology and... 1998The aims of the study were to isolate and to identify at species level the Prevotella strains in pus samples collected by needle aspiration from 25 Romanian patients...
The aims of the study were to isolate and to identify at species level the Prevotella strains in pus samples collected by needle aspiration from 25 Romanian patients with periodontal abscesses. Gram-stained smears and cultures on selective and nonselective media were performed from each of the 25 pus samples. The isolates were identified on the basis of Gram staining, cultural characteristics and standard biochemical reactions. The Gram-negative anaerobic bacilli isolates were biochemically characterized and identified at species level using the Rapid ID 32 A system (Bio Mérieux, France). Fifteen Prevotella isolates belonging to one of the following species: P. melaninogenica, P. denticola, P. oralis, P. loescheii and P. bivia were recovered. All Prevotella isolates reacted similarly in 20 tests in the Rapid ID 32 A system. The P. melaninogenica strain showed approximately the same biochemical profile and only two sugar fermentation tests were not constantly positive. The study confirmed that Prevotella is often involved in periodontal abscesses (> 50% of the cases) in association with other anaerobic or/and aerobic bacteria. P. melaninogenica was the most frequently isolated Prevotella species from the investigated cases.
Topics: Humans; Periodontal Abscess; Prevotella
PubMed: 9745330
DOI: No ID Found -
Journal of Clinical Periodontology Jul 1998The purpose of this investigation was to compare the levels of serum IgG antibody to 85 subgingival species in 32 refractory periodontitis, 56 successfully treated, and... (Comparative Study)
Comparative Study
The purpose of this investigation was to compare the levels of serum IgG antibody to 85 subgingival species in 32 refractory periodontitis, 56 successfully treated, and 33 periodontally healthy subjects. Refractory subjects showed mean full mouth attachment loss and/or >3 sites showing attachment loss >2.5 mm within 1 year after 2 treatment modalities, scaling and root planing and surgery plus systemically administered tetracycline. Successfully-treated subjects showed mean attachment level gain and no sites with attachment loss >2.5 mm, 1 year post-therapy. Periodontally healthy subjects exhibited no pocket or attachment level >3 mm, and no evidence of progressing attachment loss during 1 year of monitoring. Baseline serum was obtained from each subject and tested against 85 subgingival species, including reference strains and strains isolated from refractory subjects, using checkerboard immunoblotting. Significance of differences in levels of serum antibody among groups were sought using the Kruskal-Wallis test. Refractory subjects constituted a heterogeneous group based on their serum antibody response to subgingival species. Some individuals had antibody reactions to many subgingival species, while other subjects showed fewer or low numbers of responses. On average, refractory subjects exhibited higher numbers and levels of serum antibody reactions to a wide range of subgingival species than successfully treated or periodontally healthy subjects. Differences in serum antibody among clinical groups were more striking at higher threshold levels of antibody (>50 microg/ml and > 100 microg/ml). The data showed that a subject was 10.1 x more likely to be refractory if the subject exhibited antibody reactions with >9 subgingival species at >50 microg/ml (p<0.001, after adjusting for multiple comparisons). Serum antibody to a subset of the test species differed among the clinical groups. Porphyromonas gingivalis, Bacteroidesforsythus, and some strains isolated from refractory subjects (a novel Neisseria sp., Enterococcus faecalis, Prevotella loescheii and Prevotella oulora) elicited high serum antibody in the successfully treated and refractory subjects. High levels of serum antibody to a Microbacterium lacticum-like organism, Streptococcus oralis, Streptococcus constellatus, Actinobacillus actinonmycetemcomitans serotype c and Haemophilus aphrophilus significantly increased the likelihood of a subject being refractory to conventional periodontal therapy.
Topics: Adult; Aggregatibacter actinomycetemcomitans; Anti-Bacterial Agents; Antibodies, Bacterial; Bacteroides; Combined Modality Therapy; Dental Scaling; Disease Progression; Enterococcus faecalis; Female; Follow-Up Studies; Gingiva; Haemophilus; Humans; Immunoblotting; Immunoglobulin G; Male; Middle Aged; Neisseria; Periodontal Attachment Loss; Periodontal Pocket; Periodontitis; Porphyromonas gingivalis; Prevotella; Root Planing; Streptococcus; Streptococcus oralis; Tetracycline
PubMed: 9696261
DOI: 10.1111/j.1600-051x.1998.tb02493.x -
Infection and Immunity Jun 1998The ability of butyric acid, an extracellular metabolite from periodontopathic bacteria, to induce apoptosis in murine WEHI 231 cells, splenic B cells, and human RAJI...
The ability of butyric acid, an extracellular metabolite from periodontopathic bacteria, to induce apoptosis in murine WEHI 231 cells, splenic B cells, and human RAJI cells was examined. The culture filtrate of Porphyromonas gingivalis, Prevotella loescheii, and Fusobacterium nucleatum, which contains high a percentage of butyric acid, induced DNA fragmentation in WEHI 231 cells. Volatile fatty acid, especially butyric acid, significantly suppressed B-cell viability in a concentration-dependent fashion. The DNA fragmentation assay indicated that butyric acid rapidly induced apoptosis in WEHI 231 cells (with 1.25 mM butyric acid and 6 h after treatment), splenic B cells (with 1.25 mM butyric acid), and RAJI cells (with 2.5 mM butyric acid). Incubation of WEHI 231 cells with butyric acid for 16 h resulted in the typical ladder pattern of DNA fragmentation and the apoptoic change such as chromatin condensation and hypodiploid nuclei. Cell cycle analysis implied that butyric acid arrested the cells at the G1 phase. The inhibitory assay suggested that butyric acid-induced apoptosis of WEHI 231 and splenic B cells was inhibited by W-7, a calmodulin inhibitor. These results suggest that calmodulin-dependent regulation is involved in the signal transduction pathway of butyric acid.
Topics: Animals; Apoptosis; B-Lymphocytes; Bacteroidaceae; Butyrates; Cell Cycle; Cells, Cultured; DNA Fragmentation; Fatty Acids; Female; Fusobacterium; Hemiterpenes; Humans; Male; Mice; Pentanoic Acids; Periodontal Diseases; Porphyromonas gingivalis; Prevotella; Propionates; Signal Transduction
PubMed: 9596720
DOI: 10.1128/IAI.66.6.2587-2594.1998 -
Clinical Infectious Diseases : An... Sep 1997The frequency of beta-lactamase production by oral pigmented Prevotella species isolated from 23 healthy young children and the minimal inhibitory concentrations (MICs)...
The frequency of beta-lactamase production by oral pigmented Prevotella species isolated from 23 healthy young children and the minimal inhibitory concentrations (MICs) for 186 available beta-lactamase-positive isolates were examined by using the chromogenic cephalosporin disk test (AB BIODISK, Solna, Sweden) and the Etest (AB BIODISK) and/or the agar dilution method of the National Committee for Clinical Laboratory Standards (Villanova, PA, USA), respectively. beta-Lactamase-positive Prevotella melaninogenica strains were isolated from all children, and more than two-thirds of the Prevotella denticola and Prevotella loescheii strains isolated from the children were beta-lactamase-positive. The beta-lactamase-producing Prevotella intermedia group consisted of Prevotella nigrescens and the P. intermedia/ P. nigrescens-like organism (PINLO); P. intermedia was not found. Only two P. nigrescens isolates but most of the PINLO isolates produced beta-lactamase. The MICs for beta-lactamase-producing strains varied between 0.38 and 64 micrograms/mL. beta-Lactamase production by oral pigmented Prevotella species colonizing young children is already frequent. The phenomenon should be taken into account in the treatment of pediatric anaerobic infections of oral origin.
Topics: Child, Preschool; Humans; Prevotella; beta-Lactamases
PubMed: 9310704
DOI: 10.1086/516208 -
Journal of Clinical Periodontology Aug 1997In 23 untreated adult periodontitis patients, the occurrence of beta-lactamase producing periodontal bacteria was determined. In addition to non-selective isolation... (Comparative Study)
Comparative Study
In 23 untreated adult periodontitis patients, the occurrence of beta-lactamase producing periodontal bacteria was determined. In addition to non-selective isolation media, selective isolation and growth of beta-lactamase positive subgingival bacterial species was carried out on blood agar plates supplemented with amoxicillin and plates with amoxicillin+clavulanic acid. Porphyromonas gingivalis, Prevotella intermedia, Actinobacillus actinomycetemcomitans, Peptostreptococcus micros, Fusobacterium nucleatum, Bacteroides forsythus and Campylobacter rectus isolates from the non-selective medium were tested for beta-lactamase activity by a nitrocefin disk method (DrySlide) and by a laboratory chromogenic nitrocefin-based test. Isolates from the amoxicillin plates that were absent on the amoxicillin/clavulanic acid plates were identified and tested for beta-lactamase production. Based on the non-selective plates, six of 23 P. intermedia isolates, 2 of 19 B. forsythus isolates and 3 of 23 F. nucleatum isolates were beta-lactamase positive. The beta-lactamase positive species Prevotella loescheii, Prevotella buccae, Prevotella buccalis and Actinomyces spp were recovered from the selective amoxicillin plates. beta-Lactamase positive subgingival species were recovered from 17 of 23 patients (74%) but usually comprised low proportions of the subgingival microbiota (range < 0.01-15%). Comparison of the DrySlide test and the nitrocefin-based laboratory test revealed full agreement of test results. beta-Lactamase activity in whole subgingival plaque was detected in 12 patient samples (52%). It was concluded that beta-lactamase activity in subgingival bacteria in adult periodontitis is a common feature. However, since the majority of the samples showed only low-level enzymatic activity, the clinical relevance of this observation with regard to therapy with unprotected enzyme-susceptible beta-lactams is uncertain, though failure on the other hand, is difficult to rule out when a mechanism of resistance is present. The majority of beta-lactamase positive strains was found among species of the Prevotella genus.
Topics: Actinomyces; Adult; Aggregatibacter actinomycetemcomitans; Amoxicillin; Amoxicillin-Potassium Clavulanate Combination; Anti-Bacterial Agents; Bacteria; Bacteroides; Campylobacter; Cephalosporins; Chromogenic Compounds; Clavulanic Acids; Culture Media; Dental Plaque; Fusobacterium nucleatum; Gingiva; Humans; Indicators and Reagents; Penicillins; Peptostreptococcus; Periodontitis; Porphyromonas gingivalis; Prevotella; Prevotella intermedia; beta-Lactamases
PubMed: 9266340
DOI: 10.1111/j.1600-051x.1997.tb00226.x