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PloS One 2018Acute apical abscess is caused by bacteria that leave the infected dental root canal to invade the periodontal tissues. Most species occurring in abscesses are also... (Comparative Study)
Comparative Study
INTRODUCTION
Acute apical abscess is caused by bacteria that leave the infected dental root canal to invade the periodontal tissues. Most species occurring in abscesses are also found in asymptomatic infections; therefore, the possibility exists that not only the presence of certain species but also their specific counts influence the appearance of symptoms. This molecular study compared the frequency and levels of several candidate endodontic pathogens in teeth with acute apical abscesses and asymptomatic apical periodontitis.
METHODS
Samples were taken from the root canals of teeth with asymptomatic apical periodontitis (n = 73) and by aspiration of purulent exudate from acute abscesses (n = 55). DNA was extracted from samples and bacterial identifications were performed by a closed-ended semi-quantitative reverse-capture checkerboard approach targeting 40 bacterial species/phylotypes.
RESULTS
Bacterial DNA was detected in all cases. In abscesses, the most prevalent taxa were Fusobacterium nucleatum (60%), Porphyromonas endodontalis (53%), Parvimonas micra (51%), and Streptococcus species (45%). The most frequently detected taxa in asymptomatic teeth were P. endodontalis (63%), Dialister invisus (58%), Olsenella uli (56%), and F. nucleatum (51%). None of the targeted taxa were significantly associated with abscesses when only mere presence was evaluated (p>0.05). However, semi-quantitative data demonstrated that P. endodontalis, Prevotella baroniae, Treponema denticola and Streptococcus species were significantly more frequent at levels >105 in abscesses than in asymptomatic cases (p<0.05).
CONCLUSION
None of the target species/phylotypes were associated with abscesses in terms of frequency. However, some taxa were significantly found in higher levels in abscesses. Presence of a potentially virulent pathogen in high counts may increase the collective pathogenicity of the bacterial community and give rise to symptoms.
Topics: Abscess; Adolescent; Adult; Aged; Bacteria; Female; Humans; Male; Middle Aged; Periapical Periodontitis; Tooth Apex; Young Adult
PubMed: 29293651
DOI: 10.1371/journal.pone.0190469 -
Journal of Periodontal & Implant Science Feb 2023The objective of this study was to analyze the microbial profile of individuals with peri-implantitis (PI) compared to those of periodontally healthy (PH) subjects and...
PURPOSE
The objective of this study was to analyze the microbial profile of individuals with peri-implantitis (PI) compared to those of periodontally healthy (PH) subjects and periodontitis (PT) subjects using Illumina sequencing.
METHODS
Buccal, supragingival, and subgingival plaque samples were collected from 109 subjects (PH: 30, PT: 49, and PI: 30). The V3-V4 region of 16S rRNA was sequenced and analyzed to profile the plaque microbiota.
RESULTS
Microbial community diversity in the PI group was higher than in the other groups, and the 3 groups showed significantly separated clusters in the buccal samples. The PI group showed different patterns of relative abundance from those in the PH and PT groups depending on the sampling site at both genus and phylum levels. In all samples, some bacterial species presented considerably higher relative abundances in the PI group than in the PH and PT groups, including , , , , , , , , and . Network analysis identified that several well-known periodontal pathogens and newly recognized bacteria were closely correlated with each other.
CONCLUSIONS
The composition of the microbiota was considerably different in PI subjects compared to PH and PT subjects, and these results could shed light on the mechanisms involved in the development of PI.
PubMed: 36468472
DOI: 10.5051/jpis.2202080104 -
Oral Diseases Sep 2012To compare the microbiota of endodontic infections in necrotic pulp from HIV-negative and HIV-positive subjects. (Comparative Study)
Comparative Study
OBJECTIVE
To compare the microbiota of endodontic infections in necrotic pulp from HIV-negative and HIV-positive subjects.
MATERIALS AND METHODS
Root canal samples from necrotic pulp were collected from 40 HIV- and 20 HIV+ subjects. Pulps were amplified using multiple displacement amplification (MDA). Then, checkerboard DNA-DNA hybridization was employed to assess the levels of 107 microbial taxa. The percentage of DNA probe count and the percentage of teeth colonized by each test species were investigated. Significant differences between groups regarding proportions of taxa and prevalence of the test species were sought using the Mann-Whitney test and the Chi-square analysis, respectively.
RESULTS
The most prevalent taxa detected were Dialister pneumosintes, Stenotrophomonas maltophilia, Streptococcus sobrinus, Corynebacterium diphteriae, and Helicobacter pylori among HIV- subjects and D. pneumosintes, Prevotella tannerae, Porphyromonas gingivalis, Parvimonas micra, Prevotella nigrescens, and Corynebacterium diphtheriae among HIV+ individuals. D. pneumosintes, C. diphtheria, and C. albicans were the most abundant species in the HIV- group, whereas the predominant taxa in HIV+ samples were P. tannerae, D. pneumosintes and Olsenella uli. P. tannerae, O. uli, Veilonella dispar, Bacteroides fragilis, and Actinomyces meyeri were significantly more abundant in HIV+ samples.
CONCLUSIONS
There were significant differences in the prevalence and proportions of specific microbial taxa between HIV- and HIV+ individuals. The root canal microbiota may represent a reservoir of important oral and medical pathogens, mainly in HIV+ individuals.
Topics: Actinomyces; Adolescent; Adult; Bacteria; Bacteroides fragilis; Candida albicans; Child; Corynebacterium diphtheriae; DNA Probes; Dental Pulp Cavity; Dental Pulp Necrosis; Female; Gram-Negative Anaerobic Straight, Curved, and Helical Rods; HIV Seronegativity; HIV Seropositivity; Helicobacter pylori; Humans; Male; Middle Aged; Nucleic Acid Amplification Techniques; Nucleic Acid Hybridization; Peptostreptococcus; Porphyromonas gingivalis; Prevotella; Prevotella nigrescens; Stenotrophomonas maltophilia; Streptococcus sobrinus; Veillonella; Young Adult
PubMed: 22335194
DOI: 10.1111/j.1601-0825.2012.01908.x -
Nature Communications Aug 2019Phosphonates are rare and unusually bioactive natural products. However, most bacterial phosphonate biosynthetic capacity is dedicated to tailoring cell surfaces with...
Phosphonates are rare and unusually bioactive natural products. However, most bacterial phosphonate biosynthetic capacity is dedicated to tailoring cell surfaces with molecules like 2-aminoethylphosphonate (AEP). Although phosphoenolpyruvate mutase (Ppm)-catalyzed installation of C-P bonds is known, subsequent phosphonyl tailoring (Pnt) pathway steps remain enigmatic. Here we identify nucleotidyltransferases in over two-thirds of phosphonate biosynthetic gene clusters, including direct fusions to ~60% of Ppm enzymes. We characterize two putative phosphonyl tailoring cytidylyltransferases (PntCs) that prefer AEP over phosphocholine (P-Cho) - a similar substrate used by the related enzyme LicC, which is a virulence factor in Streptococcus pneumoniae. PntC structural analyses reveal steric discrimination against phosphocholine. These findings highlight nucleotidyl activation as a predominant chemical logic in phosphonate biosynthesis and set the stage for probing diverse phosphonyl tailoring pathways.
Topics: Actinobacteria; Aminoethylphosphonic Acid; Bacteria; Bacterial Proteins; Biosynthetic Pathways; Cell Wall; Crystallization; Crystallography, X-Ray; Escherichia coli; N-Acylneuraminate Cytidylyltransferase; Nucleotidyltransferases; Organophosphonates; Phospholipids; Phosphorylcholine; Phosphotransferases (Phosphomutases); Polysaccharides; Substrate Specificity
PubMed: 31420548
DOI: 10.1038/s41467-019-11627-6 -
Microbiology (Reading, England) Mar 2015This study monitored the dynamics and diversity of the human faecal 'Atopobium cluster' over a 3-month period using a polyphasic approach. Fresh faecal samples were...
This study monitored the dynamics and diversity of the human faecal 'Atopobium cluster' over a 3-month period using a polyphasic approach. Fresh faecal samples were collected fortnightly from 13 healthy donors (six males and seven females) aged between 26 and 61 years. FISH was used to enumerate total (EUB338mix) and 'Atopobium cluster' (ATO291) bacteria, with counts ranging between 1.12×10(11) and 9.95×10(11), and 1.03×10(9) and 1.16×10(11) cells (g dry weight faeces)(-1), respectively. The 'Atopobium cluster' population represented 0.2-22 % of the total bacteria, with proportions donor-dependent. Denaturing gradient gel electrophoresis (DGGE) using 'Atopobium cluster'-specific primers demonstrated faecal populations of these bacteria were relatively stable, with bands identified as Collinsella aerofaciens, Collinsella intestinalis/Collinsella stercoris, Collinsella tanakaei, Coriobacteriaceae sp. PEAV3-3, Eggerthella lenta, Gordonibacter pamelaeae, Olsenella profusa, Olsenella uli and Paraeggerthella hongkongensis in the DGGE profiles of individuals. Colony PCR was used to identify 'Atopobium cluster' bacteria isolated from faeces (n = 224 isolates). 16S rRNA gene sequence analysis of isolates demonstrated Collinsella aerofaciens represented the predominant (88 % of isolates) member of the 'Atopobium cluster' found in human faeces, being found in nine individuals. Eggerthella lenta was identified in three individuals (3.6 % of isolates). Isolates of Collinsella tanakaei, an 'Enorma' sp. and representatives of novel species belonging to the 'Atopobium cluster' were also identified in the study. Phenotypic characterization of the isolates demonstrated their highly saccharolytic nature and heterogeneous phenotypic profiles, and 97 % of the isolates displayed lipase activity.
Topics: Actinobacteria; Adult; Bacteria; Biodiversity; DNA, Bacterial; DNA, Ribosomal; Feces; Female; Humans; Male; Microbiota; Middle Aged; Molecular Sequence Data; Phenotype; Phylogeny; RNA, Ribosomal, 16S
PubMed: 25533445
DOI: 10.1099/mic.0.000016 -
Journal of Clinical Microbiology Jul 2005Endodontic infections have been traditionally studied by culture methods, but recent reports showing that over 50% of the oral microbiota is still uncultivable (B. J....
Endodontic infections have been traditionally studied by culture methods, but recent reports showing that over 50% of the oral microbiota is still uncultivable (B. J. Paster et al., J. Bacteriol. 183:3770-3783, 2001) raise the possibility that many endodontic pathogens remain unknown. This study intended to investigate the prevalence of several uncultivated oral phylotypes, as well as newly named species in primary or persistent endodontic infections associated with chronic periradicular diseases. Samples were taken from the root canals of 21 untreated teeth and 22 root-filled teeth, all of them with radiographic evidence of periradicular bone destruction. Genomic DNA was isolated directly from each sample, and 16S rRNA gene-based nested or heminested PCR assays were used to determine the presence of 13 species or phylotypes of bacteria. Species-specific primers had already been validated in the literature or were developed by aligning closely related 16S rRNA gene sequences. Species specificity for each primer pair was confirmed by running PCRs against a panel of several oral bacteria and by sequencing DNA from representative positive samples. All species or phylotypes were detected in at least one case of primary infections. The most prevalent species or phylotypes found in primary infections were Dialister invisus (81%), Synergistes oral clone BA121 (33%), and Olsenella uli (33%). Of the target bacteria, only these three species were detected in persistent infections. Detection of uncultivated phylotypes and newly named species in infected root canals suggests that there are previously unrecognized bacteria that may play a role in the pathogenesis of periradicular diseases.
Topics: Actinobacteria; Bacteria; Chronic Disease; Culture Media; DNA Primers; DNA, Bacterial; DNA, Ribosomal; Dental Pulp Cavity; Dental Pulp Diseases; Humans; Periapical Diseases; Polymerase Chain Reaction; RNA, Ribosomal, 16S; Veillonellaceae
PubMed: 16000454
DOI: 10.1128/JCM.43.7.3314-3319.2005 -
Journal of Clinical Microbiology May 2003Due to the inadequate automation in the amplification and sequencing procedures, the use of 16S rRNA gene sequence-based methods in clinical microbiology laboratories is...
Usefulness of the MicroSeq 500 16S ribosomal DNA-based bacterial identification system for identification of clinically significant bacterial isolates with ambiguous biochemical profiles.
Due to the inadequate automation in the amplification and sequencing procedures, the use of 16S rRNA gene sequence-based methods in clinical microbiology laboratories is largely limited to identification of strains that are difficult to identify by phenotypic methods. In this study, using conventional full-sequence 16S rRNA gene sequencing as the "gold standard," we evaluated the usefulness of the MicroSeq 500 16S ribosomal DNA (rDNA)-based bacterial identification system, which involves amplification and sequencing of the first 527-bp fragment of the 16S rRNA genes of bacterial strains and analysis of the sequences using the database of the system, for identification of clinically significant bacterial isolates with ambiguous biochemical profiles. Among 37 clinically significant bacterial strains that showed ambiguous biochemical profiles, representing 37 nonduplicating aerobic gram-positive and gram-negative, anaerobic, and Mycobacterium species, the MicroSeq 500 16S rDNA-based bacterial identification system was successful in identifying 30 (81.1%) of them. Five (13.5%) isolates were misidentified at the genus level (Granulicatella adiacens was misidentified as Abiotrophia defectiva, Helcococcus kunzii was misidentified as Clostridium hastiforme, Olsenella uli was misidentified as Atopobium rimae, Leptotrichia buccalis was misidentified as Fusobacterium mortiferum, and Bergeyella zoohelcum was misidentified as Rimerella anatipestifer), and two (5.4%) were misidentified at the species level (Actinomyces odontolyticus was misidentified as Actinomyces meyeri and Arcobacter cryaerophilus was misidentified as Arcobacter butzleri). When the same 527-bp DNA sequences of these seven isolates were compared to the known 16S rRNA gene sequences in the GenBank, five yielded the correct identity, with good discrimination between the best and second best match sequences, meaning that the reason for misidentification in these five isolates was due to a lack of the 16S rRNA gene sequences of these bacteria in the database of the MicroSeq 500 16S rDNA-based bacterial identification system. In conclusion, the MicroSeq 500 16S rDNA-based bacterial identification system is useful for identification of most clinically important bacterial strains with ambiguous biochemical profiles, but the database of the MicroSeq 500 16S rDNA-based bacterial identification system has to be expanded in order to encompass the rarely encountered bacterial species and achieve better accuracy in bacterial identification.
Topics: Bacteria; Bacterial Typing Techniques; Base Sequence; DNA Primers; DNA, Bacterial; DNA, Ribosomal; Humans; Polymerase Chain Reaction; RNA, Bacterial; RNA, Ribosomal, 16S
PubMed: 12734240
DOI: 10.1128/JCM.41.5.1996-2001.2003