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Microorganisms Jan 2023The aim of this study was to investigate and clarify the ambiguous taxonomy of and its closely related species using state-of-the-art high-throughput sequencing...
The aim of this study was to investigate and clarify the ambiguous taxonomy of and its closely related species using state-of-the-art high-throughput sequencing techniques, and, furthermore, to determine whether sub-clusters identified within and in a previous study by multi locus sequence typing (MLST) using concatenation of seven housekeeping genes should either be classified as subspecies or distinct species. The strains in this study were broadly classified under group as genospecies I and genospecies II. Based on MLST data analysis, these were further classified as and . The whole genome sequencing of selected strains of ( = 17) and ( = 19) was carried out using Illumina Genome Analyzer IIxe and Roche 454 allowing paired-end and single-reads sequencing, respectively. The sequences obtained were aligned using CLC Genomic workbench version 5.1 and annotated using RAST (Rapid Annotation using Subsystem Technology) release version 59 accessible online. Additionally, genomes of seven publicly available strains of (k20, MG1, c505, OT175, OT171, OT170, and ) were also included. Comparative genomic analysis (CGA) using Mauve, Progressive Mauve, gene-by-gene, Core, and Pan Genome, and finally Digital DNA-DNA homology (DDH) analysis was carried out. DDH values were obtained using in silico genome-genome comparison. Evolutionary analysis using ClonalFrame was also undertaken. The mutation and recombination events were compared using chi-square test among and isolates (analysis methods are not included in the study). CGA results were consistent with previous traditional classification using MLST. It was found that strains of k20, MG1, c505, and OT175 clustered in group of isolates, while OT171, OT170, and appeared as separate branches. Similar clustering to MLST was observed for other isolates. The mutation and recombination events were significantly higher in than , highlighting the diversity of strains in the oral cavity. These findings suggest that forms six distinct groups, whereas forms three. The correct designation of isolates will help in the identification of clinical isolates found in dental plaque. Easily accessible online genomic sequence data will also accelerate the investigation of the biochemical characterisation and pathogenesis of this important group of micro-organisms.
PubMed: 36838222
DOI: 10.3390/microorganisms11020254 -
Microorganisms Jan 2020The study of bacterial interaction between Streptococcus mutans and Actinomyces naeslundii may disclose important features of biofilm interspecies relationships. The aim...
The study of bacterial interaction between Streptococcus mutans and Actinomyces naeslundii may disclose important features of biofilm interspecies relationships. The aim of this study was to characterize-with an emphasis on biofilm formation and composition and metabolic activity-single- and dual-species biofilms of S. mutans or A. naeslundii, and to use a drip flow reactor (DFR) to evaluate biofilm stress responses to 0.2% chlorhexidine diacetate (CHX). Single- and dual-species biofilms were grown for 24 h. The following factors were evaluated: cell viability, biomass and total proteins in the extracellular matrix, 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide-"XTT"-reduction and lactic acid production. To evaluate stress response, biofilms were grown in DFR. Biofilms were treated with CHX or 0.9% sodium chloride (NaCl; control). Biofilms were plated for viability assessment. Confocal laser-scanning microscopy (CLSM) was also performed. Data analysis was carried out at 5% significance level. viability and lactic acid production in dual-species biofilms were significantly reduced. showed a higher resistance to CHX in dual-species biofilms. Total protein content, biomass and XTT reduction showed no significant differences between single- and dual-species biofilms. CLSM images showed the formation of large clusters in dual-species biofilms. In conclusion, dual-species biofilms reduced viability and lactic acid production and increased resistance to chlorhexidine.
PubMed: 32023892
DOI: 10.3390/microorganisms8020194 -
BMC Oral Health Jun 2023Streptococcus, Bifidobacteria, Lactobacillus and Actinomyces are acidogenic aciduria that may be associated with root caries (RC). The aim of the study was to analyze...
BACKGROUND
Streptococcus, Bifidobacteria, Lactobacillus and Actinomyces are acidogenic aciduria that may be associated with root caries (RC). The aim of the study was to analyze Streptococcus mutans (S. mutans), Streptococcus sobrinus (S. sobrinus), Bifidobacterium spp., Lactobacillus spp. and Actinomyces naeslundii (A. naeslundii) in the saliva of nursing home elderly, to assess the correlation between bacterial composition and RC for five putative catiogenic organisms.
METHODS
In this study, we collected 43 saliva samples and divided into two groups: the root caries group (RCG, n = 21) and the caries-free group (CFG, n = 22). Bacterial DNA was extracted from the saliva samples. The presence and abundance of the five microorganisms were detected by Quantitative real-time PCR (qPCR). Spearman correlation test was performed to evaluate the relationship between the numbers of root decayed filled surfaces (RDFS) and root caries index (RCI) and salivary levels of the bacteria.
RESULTS
The salivary levels of S. mutans, S. sobrinus, Bifidobacterium spp. and Lactobacillus spp. were significantly higher in RCG than in CFG (p < 0.05). RDFS and RCI (RDFS/RCI) were positively associated with salivary levels of S. mutans, S. sobrinus and Bifidobacterium spp. (r = 0.658/0.635, r = 0.465/0.420 and r = 0.407/0.406, respectively). No significant differences in presence and amounts of A. naeslundii was observed between the two groups (p > 0.05).
CONCLUSION
S. mutans, S. sobrinus and Bifidobacterium spp. in saliva appear to be associated with RC in the elderly. Taken together, the findings indicate that specific salivary bacteria may be involved in the progression of RC.
Topics: Humans; Aged; Root Caries; Streptococcus mutans; Streptococcus sobrinus; Dental Caries; Saliva; Nursing Homes
PubMed: 37270529
DOI: 10.1186/s12903-023-02953-9 -
Journal of Biotechnology May 2017Infections induced by oral biofilms include caries, as well as periodontal, and peri-implant disease, and may influence quality of life, systemic health, and... (Review)
Review
Infections induced by oral biofilms include caries, as well as periodontal, and peri-implant disease, and may influence quality of life, systemic health, and expenditure. As bacterial biofilms are highly resistant and resilient to conventional antibacterial therapy, it has been difficult to combat these infections. An innovative alternative to the biocontrol of oral biofilms could be to use bacteriophages or phages, the viruses of bacteria, which are specific, non-toxic, self-proliferating, and can penetrate into biofilms. Phages for Actinomyces naeslundii, Aggregatibacter actinomycetemcomitans, Enterococcus faecalis, Fusobacterium nucleatum, Lactobacillus spp., Neisseria spp., Streptococcus spp., and Veillonella spp. have been isolated and characterised. Recombinant phage enzymes (lysins) have been shown to lyse A. naeslundii and Streptococcus spp. However, only a tiny fraction of available phages and their lysins have been explored so far. The unique properties of phages and their lysins make them promising but challenging antimicrobials. The genetics and biology of phages have to be further explored in order to determine the most effective way of applying them. Studying the effect of phages and lysins on multispecies biofilms should pave the way for microbiota engineering and microbiota-based therapy.
Topics: Bacterial Infections; Bacteriophages; Biofilms; Humans; Mouth; Mouth Diseases
PubMed: 28108235
DOI: 10.1016/j.jbiotec.2017.01.002 -
Antibiotics (Basel, Switzerland) Oct 2020Actinomycosis is a chronic bacterial infection characterized by continuous local spread, irrespective of anatomical barriers, and granulomatous suppurative inflammation....
Actinomycosis is a chronic bacterial infection characterized by continuous local spread, irrespective of anatomical barriers, and granulomatous suppurative inflammation. Due to its expansive local growth, it can simulate a malignant tumour. Subsequent hematogenous dissemination to distant organs can mimic metastases and further increase suspicion for malignancy. A case of severe disseminated pelvic actinomycosis associated with intrauterine device is described here. The patient presented with a pelvic mass mimicking a tumour, bilateral ureteral obstruction, ascites, multinodular involvement of the liver, lungs and spleen, inferior vena cava thrombosis and extreme cachexia. Actinomycosis was diagnosed by liver biopsy and confirmed by culture of from extracted intrauterine contraceptive device (IUD). Prolonged treatment with aminopenicillin and surgery resulted in recovery with moderate sequelae.
PubMed: 33137889
DOI: 10.3390/antibiotics9110748 -
Journal of Dental Research Mar 2022An intuitive, clinically relevant index of microbial dysbiosis as a summary statistic of subgingival microbiome profiles is needed. Here, we describe a subgingival...
An intuitive, clinically relevant index of microbial dysbiosis as a summary statistic of subgingival microbiome profiles is needed. Here, we describe a subgingival microbial dysbiosis index (SMDI) based on machine learning analysis of published periodontitis/health 16S microbiome data. The raw sequencing data, split into training and test sets, were quality filtered, taxonomically assigned to the species level, and centered log-ratio transformed. The training data set was subject to random forest analysis to identify discriminating species (DS) between periodontitis and health. DS lists, compiled by various "Gini" importance score cutoffs, were used to compute the SMDI for samples in the training and test data sets as the mean centered log-ratio abundance of periodontitis-associated species subtracted by that of health-associated ones. Diagnostic accuracy was assessed with receiver operating characteristic analysis. An SMDI based on 49 DS provided the highest accuracy with areas under the curve of 0.96 and 0.92 in the training and test data sets, respectively, and ranged from -6 (most normobiotic) to 5 (most dysbiotic) with a value around zero discriminating most of the periodontitis and healthy samples. The top periodontitis-associated DS were spp., and , while and were the top health-associated DS. The index was highly reproducible by hypervariable region. Applying the index to additional test data sets in which nitrate had been used to modulate the microbiome demonstrated that nitrate has dysbiosis-lowering properties in vitro and in vivo. Finally, 3 genera (, and ) were identified that could be used for calculation of a simplified SMDI with comparable accuracy. In conclusion, we have developed a nonbiased, reproducible, and easy-to-interpret index that can be used to identify patients/sites at risk of periodontitis, to assess the microbial response to treatment, and, importantly, as a quantitative tool in microbiome modulation studies.
Topics: Dysbiosis; Humans; Microbiota; Periodontitis; RNA, Ribosomal, 16S; Treponema denticola
PubMed: 34428955
DOI: 10.1177/00220345211035775 -
Microorganisms Aug 2023Acne vulgaris is a common inflammatory condition that is multi-factorial and impacted by both intrinsic and extrinsic features. Several previous studies have assessed...
Acne vulgaris is a common inflammatory condition that is multi-factorial and impacted by both intrinsic and extrinsic features. Several previous studies have assessed for correlations between factors such as circulating hormones, stress, or the microbiome. However, there have not been any correlations specifically against lesion counts or differentiating correlations between inflammatory and non-inflammatory lesion counts. Here, we correlate several factors against acne lesions. Twenty men and women with mild to moderate acne were recruited, and their hormonal levels and their gut microbiome were collected and correlated against their inflammatory and non-inflammatory lesions of acne. Facial non-inflammatory lesions were weakly correlated to sebum excretion rate and weakly inversely correlated to forehead and cheek hydration. We examined stress through the use of a normalized peak-to-trough ratio (higher numbers indicated less stress), which correlated with skin hydration and inversely correlated with sebum excretion rate. Sebum excretion rate was weakly correlated to testosterone levels, and facial hydration correlated with estradiol levels. Correlations with the gut microbiome showed differential correlations with inflammatory and non-inflammatory lesions, with correlating to inflammatory lesion counts, while correlated to non-inflammatory lesions. Overall, measures of stress and circulating hormones correlate to skin biophysical properties and acne lesion counts. Also, different gut bacteria correlate with either inflammatory or non-inflammatory lesion counts. We hope that our findings stimulate further work on the gut-mind-stress-skin axis within acne.
PubMed: 37630609
DOI: 10.3390/microorganisms11082049 -
JDR Clinical and Translational Research Apr 2020Periodontitis is a chronic inflammatory condition initiated by microorganisms and is positively linked to systemic conditions such as cancer, cardiovascular disease, and...
INTRODUCTION
Periodontitis is a chronic inflammatory condition initiated by microorganisms and is positively linked to systemic conditions such as cancer, cardiovascular disease, and diabetes mellitus.
OBJECTIVES
To prospectively investigate associations between empirically derived clusters of IgG antibodies against 19 selected periodontal microorganisms and cancer mortality in a representative sample of the US population.
METHODS
We evaluated 6,491 participants aged ≥40 y from the Third National Health and Nutrition Examination Survey (1988 to 1994), who had complete data on IgG antibody titers against 19 selected periodontal microorganisms and were free of cardiovascular disease and cancer. In a prior study, antibodies were categorized into 4 mutually exclusive groups via cluster analysis: red-green, orange-red, yellow-orange, and orange-blue. Cluster scores were estimated by summing z scores of the antibody titers making up each cluster. Participants were followed up to death until December 31, 2011. Cox proportional hazard models were applied to estimate hazard ratios (HRs) and 95% CIs for all-cancer mortality by tertiles of cluster scores.
RESULTS
During follow-up for a median of 15.9 y, there were 2,702 deaths (31.3%), including 631 cancer-related deaths (8.1%). After adjusting for multiple confounders, the orange-blue cluster was inversely associated with cancer mortality (tertile 2 vs. tertile 1: HR = 0.67, 95% CI = 0.54 to 0.84; tertile 3 vs tertile 1: HR = 0.62, 95% CI = 0.46 to 0.84). The association between the yellow-orange cluster and all-cancer mortality was also inverse but not significant, and the orange-red cluster and the red-green cluster were not associated with all-cancer mortality.
CONCLUSIONS
Antibodies against Eubacterium nodatum and Actinomyces naeslundii may be novel predictors of cancer mortality. If further studies establish a causal relationship between these antibodies and cancer mortality, they could be targets to prevent possible systemic effects of periodontal disease with potential interventions to raise their levels.
KNOWLEDGE TRANSFER STATEMENT
Periodontal antibodies against Eubacterium nodatum and Actinomyces naeslundii were inversely associated with cancer mortality among adults followed up for an average of 16 y. Periodontal antibodies may predict cancer mortality.
Topics: Actinomyces; Antibodies, Bacterial; Humans; Immunoglobulin G; Neoplasms; Periodontitis
PubMed: 31277564
DOI: 10.1177/2380084419859484 -
Clinical Oral Investigations Oct 2023The present study aimed to evaluate the potential of the salivary pellicle (SP) formed on titanium (Ti) surfaces to modulate the formation of a biofilm composed of...
OBJECTIVES
The present study aimed to evaluate the potential of the salivary pellicle (SP) formed on titanium (Ti) surfaces to modulate the formation of a biofilm composed of Streptococcus gordonii, Actinomyces naeslundii, Fusobacterium nucleatum, and Porphyromonas gingivalis.
MATERIALS AND METHODS
Ti substrates were incubated for 2 h with a pool of saliva samples obtained from 10 systemically and periodontally healthy subjects. Enamel substrates were included as a biological reference. Scanning electron microscopy (SEM) and Raman spectroscopy analysis were used to analyze the formation of the salivary pellicle. After the SP formation, the surfaces were incubated for 12 h with a mix of Streptococcus gordonii, Actinomyces naeslundii, Fusobacterium nucleatum, and Porphyromonas gingivalis. The number of bacterial cells attached to each surface was determined by the XTT assay while bacterial viability was analyzed by fluorescence microscopy using the LIVE/DEAD® BacLight kit.
RESULTS
The SEM and Raman spectroscopy analysis confirmed the presence of a salivary pellicle formed on the tested surfaces. Regarding the biofilm formation, the presence of the SP decreases the number of the bacterial cells detected in the test surfaces, compared with the uncover substrates. Even more, the SP-covered substrates showed similar bacterial counts in both Ti and enamel surfaces, meaning that the physicochemical differences of the substrates were less determinant than the presence of the SP. While on the SP-uncover substrates, differences in the bacterial adhesion patterns were directly related to the physicochemical nature of the substrates.
CONCLUSIONS
The salivary pellicle was the main modulator in the development of the biofilm consisting of representative oral bacteria on the Ti substrates.
CLINICAL RELEVANCE
The results of this study provide valuable information on the modulatory effect of the salivary pellicle on biofilm formation; such information allows us to understand better the events involved in the formation of oral biofilms on Ti dental implants.
Topics: Humans; Dental Pellicle; Titanium; Biofilms; Bacterial Adhesion; Streptococcus gordonii; Fusobacterium nucleatum; Surface Properties
PubMed: 37646908
DOI: 10.1007/s00784-023-05230-9 -
Heliyon Feb 2021Surface pre-reacted glass-ionomer (S-PRG) fillers release antibacterial borate and fluoride ions. We fabricated nanoscale S-PRG fillers (S-PRG nanofillers) for...
OBJECTIVES
Surface pre-reacted glass-ionomer (S-PRG) fillers release antibacterial borate and fluoride ions. We fabricated nanoscale S-PRG fillers (S-PRG nanofillers) for antibacterial coating of tooth surfaces and assessed the antibacterial effects of this coating in vitro. In addition, we creating a canine model of periodontitis to evaluate the effectiveness of S-PRG nanofiller application on tooth roots and improvement of periodontal parameters.
METHODS
Human dentin blocks were coated with S-PRG nanofiller (average particle size: 0.48 μm) and then characterized by scanning electron microscopy (SEM), energy dispersive X-ray spectrometer (EDX), and ion-releasing test. Antibacterial effects of dentin blocks coated with S-PRG nanofiller were examined using bacterial strains, and Next, we created an experimental model of periodontitis in furcation of premolars of beagle dogs. Then, S-PRG nanofiller coating was applied onto exposed tooth root surfaces. Periodontal parameters, gingival index (GI), bleeding on probing (BOP), probing pocket depth (PPD), and clinical attachment level (CAL), were measured from baseline until 4 weeks. In addition, bone healing was radiographically and histologically examined.
RESULTS
SEM and EDX revealed that S-PRG nanofillers uniformly covered the dentin surface after coating. Dentin blocks coated with S-PRG nanofiller showed ion-releasing property, bacterial growth inhibition, and sterilization effects. In the experimental periodontitis model, S-PRG nanofiller coating significantly reduced clinical inflammatory parameters, such as GI (P < 0.01) and BOP (P < 0.05), compared to uncoated samples. In addition, PPD and CAL significantly decreased by S-PRG nanofiller coating (2 weeks: P < 0.05; 3 and 4 weeks: P < 0.01), suggesting the improvement of periodontitis. Micro-CT and histology revealed that bone healing of furcation defects was enhanced by S-PRG nanofiller coating.
CONCLUSION
S-PRG nanofiller coating provides antibacterial effects to tooth surfaces and improves clinical parameters of periodontitis.
PubMed: 33644453
DOI: 10.1016/j.heliyon.2021.e06147