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Inhibitory effect of lactoperoxidase-generated hypothiocyanite upon black pigmented anaerobe growth.International Journal of Molecular... Jul 2001This study aimed to evaluate the in vitro effect of lactoperoxidase with or without its substrates (hydrogen peroxide, thiocyanate) on the growth of 4 different black...
This study aimed to evaluate the in vitro effect of lactoperoxidase with or without its substrates (hydrogen peroxide, thiocyanate) on the growth of 4 different black pigmented anaerobe (BPA) strains associated with the development and progress of periodontal diseases: Porphyromonas gingivalis ATCC 33277, Prevotella intermedia NCTC 9336, Prevotella loescheii ATCC 15930, and Prevotella melaninogenica NCTC 9338. A 5-min lactoperoxidase-generated OSCN--HOSCN incubation at pH 6.0, 7.0 or 8.0 resulted in a decrease of the growth rate (tested by turbidimetry in liquid cultures) of the 4 BPA strains, whilst lactoperoxidase alone actually promoted bacterial growth.
Topics: Analysis of Variance; Cell Division; Glucose Oxidase; Hydrogen Peroxide; Hydrogen-Ion Concentration; Lactoperoxidase; Porphyromonas gingivalis; Prevotella; Prevotella melaninogenica; Thiocyanates; Time Factors
PubMed: 11408950
DOI: No ID Found -
APMIS : Acta Pathologica,... Feb 2001Although clinically distinctive types of periodontal disease are known to be associated with HIV infection, the pathogenesis remains unclear. In the present study, the...
Although clinically distinctive types of periodontal disease are known to be associated with HIV infection, the pathogenesis remains unclear. In the present study, the subgingival microflora of 21 HIV-infected and 11 HIV-free ethnic Chinese were studied using the direct microscopic and anaerobic culture methods. Motile curved rods were found to be three times higher in the HIV-infected group under direct microscopy. Otherwise, there were no significant differences between the diseased and healthy groups when analyzed either in relation to the morphotype distribution or Gram stain morphology or oxygen tolerance. The most common bacteria isolated were Capnocytophaga species followed by Prevotella loescheii, Streptococcus sanguinis, Lactobacillus spp. and Fusobacterium spp. Although there were 20 bacterial species that were strictly limited to the HIV-infected group, and 5 limited to the healthy group, none of the species was a predominant isolate in either group (p>0.05). These findings agree with previous studies which report that subgingival bacteria of HIV-infected individuals (with or without periodontal disease) are similar to those found in healthy HIV-free individuals (with or without periodontal disease). Further work examining the subgingival microflora from patients with specific and/or severe forms of HIV-associated periodontal disease is required to shed light on the pathogenesis of this complex clinical entity.
Topics: Adult; Asian People; Bacteria; Cell Count; Gingiva; HIV Infections; HIV-1; Humans; Male; Middle Aged
PubMed: 11398993
DOI: 10.1034/j.1600-0463.2001.d01-113.x -
Archives of Oral Biology Aug 2001A proline-specific dipeptidyl aminopeptidase, dipeptidyl peptidase IV (EC 3.4.14.5), was purified from a cell sonicate soluble fraction of Prevotella loescheii ATCC...
A proline-specific dipeptidyl aminopeptidase, dipeptidyl peptidase IV (EC 3.4.14.5), was purified from a cell sonicate soluble fraction of Prevotella loescheii ATCC 15930 by sequential column chromatography. The molecular mass of the native enzyme was estimated as 160 kDa by high-pressure liquid gel filtration column chromatography and unheated sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). The subunit molecular mass was 80 kDa when the enzyme was heated to 100 degrees C in the presence of 2-mercaptoethanol before SDS-PAGE, suggesting that the native enzyme consists of two identical subunits and is folded in 2% SDS. The optimum pH, with glycyl-prolyl-4-methyl-coumaryl-7-amide as the substrate, was 8.0; the isoelectric point was 5.2. Purified enzyme showed a strong preference for dipeptide substrates containing proline and, less efficiently, alanine in the P1 position. The enzyme was markedly inhibited by Cd(2+), Zn(2+), Hg(2+), Co(2+), and serine proteinase inhibitor di-isopropylfluorophosphate.
Topics: Alanine; Cadmium; Chromatography; Chromatography, Gel; Chromatography, High Pressure Liquid; Cobalt; Coumarins; Dipeptides; Dipeptidyl Peptidase 4; Electrophoresis, Polyacrylamide Gel; Enzyme Inhibitors; Fluorescent Dyes; Humans; Hydrogen-Ion Concentration; Isoelectric Point; Isoflurophate; Mercaptoethanol; Mercury; Molecular Weight; Prevotella; Proline; Protease Inhibitors; Serine Proteinase Inhibitors; Zinc
PubMed: 11389867
DOI: 10.1016/s0003-9969(00)00065-0 -
The Journal of Antimicrobial... Mar 2001
Topics: Anti-Bacterial Agents; Bacteroidaceae Infections; Drug Resistance, Microbial; Empyema, Subdural; Humans; Male; Metronidazole; Microbial Sensitivity Tests; Middle Aged; Prevotella
PubMed: 11222578
DOI: 10.1093/jac/47.3.366 -
Journal of Periodontology Dec 2000The purpose of this study was to evaluate the clinical and microbiological effects of systemic ornidazole (ORN) in sites with or without subgingival debridement in... (Comparative Study)
Comparative Study
BACKGROUND
The purpose of this study was to evaluate the clinical and microbiological effects of systemic ornidazole (ORN) in sites with or without subgingival debridement in early-onset periodontitis (EOP) patients.
METHODS
Two pooled bacterial samples consisting of 4 sites each (scaled and non-scaled sites) were obtained from 30 individuals exhibiting EOP. All patients received oral hygiene instruction (OHI), supragingival scaling and ORN. Subgingival scaling and root planing (SRP) was carried out only in scaled sites. Bacterial samples were taken at baseline (BL) and 1 week and 2, 6, and 12 months after systemic ornidazole administration (500 mg/bid for 7 days). One more sample was taken at scaled sites, one week after SRP.
RESULTS
One week following SRP (scaled sites) Gram-negative facultative and anaerobic rods were significantly reduced while Gram-positive facultative cocci were significantly increased. After ORN administration, P. gingivalis, P. denticola, P. intermedia, B. forsythus, C. rectus, and S. sputigena were no longer detectable in either scaled or non-scaled sites. A statistically significant long-term (2, 6, and 12 months) reduction of P. gingivalis, P. intermedia, P. loescheii, B. forsythus, and C. rectus and a pronounced increase of S. milleri, S. oralis, and S. sanguis counts in both scaled and non-scaled sites were detected in comparison to baseline. A sustained reduction of bleeding tendency and of probing depth was also observed in both scaled and non-scaled sites.
CONCLUSIONS
ORN combined with SRP effects beneficial shifts in the bacterial population associated with substantial clinical improvement, thereby indicating that ORN is effective adjunct in the treatment of EOP deep periodontal pockets where anaerobic bacteria are predominant.
Topics: Administration, Oral; Adult; Aggregatibacter actinomycetemcomitans; Aggressive Periodontitis; Anti-Bacterial Agents; Bacteroides; Campylobacter; Combined Modality Therapy; Dental Scaling; Female; Follow-Up Studies; Gingival Hemorrhage; Humans; Male; Oral Hygiene; Ornidazole; Periodontal Pocket; Porphyromonas gingivalis; Prevotella; Prevotella intermedia; Root Planing; Selenomonas; Statistics, Nonparametric; Streptococcus; Streptococcus oralis; Streptococcus sanguis; Subgingival Curettage
PubMed: 11156043
DOI: 10.1902/jop.2000.71.12.1862 -
Oral Microbiology and Immunology Apr 2000A diversity of microbial species has been detected in children's oral flora at an early age. To investigate the composition of the subgingival microbiota of different... (Comparative Study)
Comparative Study
A diversity of microbial species has been detected in children's oral flora at an early age. To investigate the composition of the subgingival microbiota of different groups of teeth in children with mixed dentition, 40 systemically healthy children, aged 7-8 years, randomly chosen, were examined. Subgingival plaque samples were taken from the mesiobuccal sites of 21, 41, 16 and 36 permanent teeth and 53, 73, 64 and 84 deciduous teeth. The samples were cultured for bacterial isolation anaerobically and in 10% CO2 plus air using selective and nonselective media. Forty-five different microbial species were isolated from both permanent and deciduous teeth. Streptococcus sanguis (79-70%), Streptococcus mitis (66-65%), Prevotella melaninogenica (51-57%), Eikenella corrodens (51-52%), Capnocytophaga gingivalis (46-34%), Capnocytophaga ochracea (45-45%), Actinomyces naeslundii (39-60%) and Prevotella intermedia (42-35%) were among the most frequently detected species in permanent and deciduous teeth respectively. Several suspected periodontal pathogens, such as Porphyromonas gingivalis, Prevotella loescheii, Campylobacter gracilis, Bacteroides forsythus, Campylobacter concisus, Peptostreptococcus micros and Selenomonas sputigena, albeit less frequently detected, were present in the microbiota of these children. The bacterial species Streptococcus constellatus, Peptostreptococcus micros, Pseudoramibacter alactolyticus, E. corrodens and Fusobacterium nucleatum were associated with non-bleeding permanent and deciduous teeth whereas Streptococcus intermedius, C. concisus, P. intermedia and P. loescheii were associated with bleeding.
Topics: Actinomyces; Capnocytophaga; Child; Eikenella; Female; Gingiva; Hemorrhage; Humans; Male; Prevotella; Streptococcus; Tooth; Tooth, Deciduous
PubMed: 11155173
DOI: 10.1034/j.1399-302x.2000.150206.x -
Current Microbiology Feb 2001Heat shock proteins play an important role in bacterial survival and response to environmental stress. We cloned the Prevotella loescheii HSP70 homolog (dnaK) and...
Heat shock proteins play an important role in bacterial survival and response to environmental stress. We cloned the Prevotella loescheii HSP70 homolog (dnaK) and characterized the coding sequence, regulatory regions, and evolutionary relationships to other bacteria. Predicted proteins encoded by the P. loescheii dnaK homolog (open reading frame ORF-1) and two downstream coding regions, ORF-2 and ORF-3, are highly homologous to the proteins encoded by ORF-4 (dnaK), ORF-5, and ORF-6 from the dnaK region of Porphyromonas gingivalis. The dnaK promoter resembles other HSP (heat shock protein) promoters. Alignment of the predicted protein encoded by ORF-2 showed significant homology to the Bacteroides fragilis tnpA gene from the transposon Tn4555, whereas the ORF-3 protein showed homology to B. fragilis transposase (Tn5220) and integrase (Tn4555) proteins. This suggests a transposition-like event may be responsible for transfer of these genes between Porphyromonas and Prevotella.
Topics: Amino Acid Sequence; Base Sequence; Escherichia coli Proteins; Evolution, Molecular; Genes, Bacterial; HSP70 Heat-Shock Proteins; Models, Genetic; Molecular Sequence Data; Nucleic Acid Conformation; Open Reading Frames; Porphyromonas gingivalis; Prevotella; RNA, Bacterial; RNA, Messenger; Sequence Homology, Amino Acid
PubMed: 11136127
DOI: 10.1007/s0028403313 -
Systematic and Applied Microbiology Dec 1999The genetic diversity and relationships within the genus Prevotella were studied by analyzing twenty-five strains by multilocus enzyme electrophoresis (MLEE) at nine...
The genetic diversity and relationships within the genus Prevotella were studied by analyzing twenty-five strains by multilocus enzyme electrophoresis (MLEE) at nine metabolic enzyme loci and DNA-DNA hybridization. MLEE revealed a high genetic diversity with 25 electrophoretic types (ETs) for the 25 strains studied, a mean number of alleles per enzyme locus of 6.8 and a mean genetic diversity per locus of 0.786. The index of association described by Maynard Smith et al. (1993) revealed a clonal structure within the genus Prevotella. A dendrogram generated by cluster analysis of a matrix of ETs showed that species like P. bivia, P. buccae, P. oris, P. oralis, P. nigrescens, and P. denticola form clusters that are consistent with DNA homologies. However, strains identified as P. melaninogenica or P. loescheii by DNA-DNA hybridization did not constitute distinct subpopulations in MLEE. MLEE analysis demonstrated its high power in differentiating closely related strains. It provides an alternative to 16S rRNA analysis for the study of phylogenetic relationships within the genus Prevotella, especially for differentiating strains with high DNA homology or high rRNA homology.
Topics: Alleles; Bacteroidaceae Infections; DNA, Bacterial; Electrophoresis, Polyacrylamide Gel; Enzymes; Genes, Bacterial; Humans; Nucleic Acid Hybridization; Phylogeny; Polymorphism, Genetic; Prevotella
PubMed: 10794148
DOI: 10.1016/S0723-2020(99)80013-7 -
Journal of Periodontal Research Feb 2000Eruption of primary teeth has a great influence on the oral environment by providing suitable niches for bacterial colonization. The aim of the study was to investigate...
Eruption of primary teeth has a great influence on the oral environment by providing suitable niches for bacterial colonization. The aim of the study was to investigate the composition of the subgingival microbiota of primary incisors, canines and molars in 40 systemically healthy children aged 4-5 yr, chosen randomly. Subgingival plaque samples were taken from the mesiobuccal sites of primary incisors (61, 81), canines (53, 73) and molars (64, 84). The samples were cultured for bacterial isolation anaerobically and in 10% CO2 plus air using selective and non-selective media. Forty-one different microbial species were isolated. Gemella morbillorum and Peptostreptococcus magnus were statistically significantly more frequently detected in incisors while P. micros, Streptococcus intermedius, Bacteroides forsythus, Fusobacterium nucleatum, Prevotella loeschei, P. melaninogenica and Selenomonas sputigena were more frequently detected in molars. The bacterial species S. constellatus, G. morbillorum and P. magnus were isolated in greater numbers in incisors and P. micros, S. intermedius, Campylobacter concisus, Bacteroides egertheii, B. forsythus, P. oralis and S. sputigena were isolated in greater numbers in molars, respectively. Cluster analysis revealed 4 clusters in which 6-7 bacterial species were elevated above mean levels. Cluster I was predominated by S. constellatus, S. mitis, S. sanguis, G. morbillorum, P. melaninogenica and P. oralis; cluster II was predominated by S. sanguis, Actinomyces naeslundii, Capnocytophaga gingivalis, C. ochracea and P. intermedia; cluster III was predominated by S. mitis, C. ochracea, F. nucleatum, P. loeschei, P. melaninogenica and P. oralis; and finally cluster IV was predominated by S. sanguis, C. gingivalis, Veillonella parvula, Campylobacter gracilis, F. nucleatum and P. intermedia. The bacterial species S. constellatus, P. micros, Pseudoramibacter alactolyticus, Eikenella corrodens and F. nucleatum were associated with non-bleeding sites while S. intermedius, C. concisus, P. intermedia and P. loescheii were found more frequently in bleeding sites.
Topics: Actinomyces; Analysis of Variance; Bacteria, Anaerobic; Child, Preschool; Cluster Analysis; Colony Count, Microbial; Dental Plaque; Dental Plaque Index; Female; Humans; Likelihood Functions; Male; Periodontal Index; Sampling Studies; Streptococcus sanguis; Tooth, Deciduous
PubMed: 10791707
DOI: 10.1034/j.1600-0765.2000.035001033.x -
Canadian Journal of Microbiology Feb 1999This study investigated the involvement of RNA folding in the synthesis of a fusion protein with beta-galactosidase activity. The coding gap region of the Prevotella...
This study investigated the involvement of RNA folding in the synthesis of a fusion protein with beta-galactosidase activity. The coding gap region of the Prevotella loescheii adhesin gene plaA was fused in-frame with the Escherichia coli lacZ gene on plasmid pSK105. N-Terminal sequencing of the expressed plaA-lacZ protein indicated that it resulted from translational initiation at a fortuitous ribosomal-binding site within the plaA sequence at nt 570. Specific mutations were introduced in the stem-loop region that precedes the gap sequence. Analysis of stem-loop mutants, together with the introduction of compensatory mutations that restored activity, supports a requirement for stem-loop formation within the plaA sequence preceding the translational initiation site. A mutation reducing the predicted size of the loop, but preserving the stem structure, inactivated fusion protein synthesis. A suppressor mutation predicted to restore the size of the loop restored efficient fusion protein synthesis. In addition, the sequence preceding the translational start site of the plaA-lacZ fusion has several similarities to sequences that function as translational enhancers in prokaryotes. These include a stem-loop structure, an A-U rich region preceding the initiation codon, and a region of homology to 16S rRNA.
Topics: Adhesins, Bacterial; Amino Acid Sequence; Base Sequence; Escherichia coli; Galactosides; Genes, Bacterial; Lac Operon; Lectins; Molecular Sequence Data; Mutagenesis, Site-Directed; Nucleic Acid Conformation; Prevotella; Protein Folding; RNA, Bacterial; RNA, Messenger; Recombinant Fusion Proteins
PubMed: 10380648
DOI: No ID Found