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World Journal of Microbiology &... Oct 2023Dental biofilms represent a serious oral health problem playing a key role in the development of caries and other oral diseases. In the present work, we cloned and...
Dental biofilms represent a serious oral health problem playing a key role in the development of caries and other oral diseases. In the present work, we cloned and expressed in E. coli two glucanases, Prevotella melaninogenica mutanase (PmGH87) and Capnocytophaga ochracea dextranase (CoGH66), and characterized them biochemically and biophysically. Their three-dimensional structures were elucidated and discussed. Furthermore, we tested the capacity of the enzymes to hydrolyze mutan and dextran to prevent formation of Streptococcus mutans biofilms, as well as to degrade pre- formed biofilms in low and abundant sugar conditions. The percentage of residual biofilm was calculated for each treatment group in relation to the control, as well as the degree of synergism. Our results suggest that both PmGH87 and CoGH66 are capable of inhibiting biofilm formation grown under limited or abundant sucrose conditions. Degradation of pre-formed biofilms experiments reveal a time-dependent effect for the treatment with each enzyme alone. In addition, a synergistic and dose-dependent effects of the combined enzymatic treatment with the enzymes were observed. For instance, the highest biomass degradation was 95.5% after 30 min treatment for the biofilm grown in low sucrose concentration, and 93.8% after 2 h treatment for the biofilm grown in sugar abundant condition. Strong synergistic effects were observed, with calculated degree of synergism of 5.54 and 3.18, respectively and their structural basis was discussed. Jointly, these data can pave the ground for the development of biomedical applications of the enzymes for controlling growth and promoting degradation of established oral biofilms.
Topics: Escherichia coli; Prevotella melaninogenica; Biofilms; Sucrose
PubMed: 37882859
DOI: 10.1007/s11274-023-03804-z -
Frontiers in Microbiology 2023The management of infectious diseases has become more critical due to the development of novel pathogenic strains with enhanced resistance. , a gram-negative bacterium,...
The management of infectious diseases has become more critical due to the development of novel pathogenic strains with enhanced resistance. , a gram-negative bacterium, was found to be involved in various infections of the respiratory tract, aerodigestive tract, and gastrointestinal tract. The need to explore novel drug and vaccine targets against this pathogen was triggered by the emergence of antimicrobial resistance against reported antibiotics to combat infections. The study involves core genes acquired from 14 complete strain genome sequences, where promiscuous drug and vaccine candidates were explored by state-of-the-art subtractive proteomics and reverse vaccinology approaches. A stringent bioinformatics analysis enlisted 18 targets as novel, essential, and non-homologous to humans and having druggability potential. Moreover, the extracellular and outer membrane proteins were subjected to antigenicity, allergenicity, and physicochemical analysis for the identification of the candidate proteins to design multi-epitope vaccines. Two candidate proteins (ADK95685.1 and ADK97014.1) were selected as the best target for the designing of a vaccine construct. Lead B- and T-cell overlapped epitopes were joined to generate potential chimeric vaccine constructs in combination with adjuvants and linkers. Finally, a prioritized vaccine construct was found to have stable interactions with the human immune cell receptors as confirmed by molecular docking and MD simulation studies. The vaccine construct was found to have cloning and expression ability in the bacterial cloning system. Immune simulation ensured the elicitation of significant immune responses against the designed vaccine. In conclusion, our study reported novel drug and vaccine targets and designed a multi-epitope vaccine against the infection. Further experimental validation will help open new avenues in the treatment of this multi-drug-resistant pathogen.
PubMed: 37808310
DOI: 10.3389/fmicb.2023.1271798 -
Journal of Oral Microbiology 2022Oral are known as anaerobic commensals on oral mucosae and in dental plaques from early life onwards, including pigmented and and non-pigmented species. Many... (Review)
Review
Oral are known as anaerobic commensals on oral mucosae and in dental plaques from early life onwards, including pigmented and and non-pigmented species. Many species contribute to oral inflammatory processes, being frequent findings in dysbiotic biofilms of periodontal diseases (), cariotic lesions ( (formerly ) ), endodontic infections (), and other clinically relevant oral conditions. Over the years, several novel species have been recovered from the oral cavity without knowledge of their clinical relevance. Within this wide genus, virulence properties and other characteristics like biofilm formation seemingly vary in a species- and strain-dependent manner, as shown for the group organisms (, and ). Oral species are identified in various non-oral infections and chronic pathological conditions. Here, we have updated the knowledge of the genus and the role of species as residents and infectious agents of the oral cavity, as well as their detection in non-oral infections, but also gathered information on their potential link to cancers of the head and neck, and other systemic disorders.
PubMed: 36393976
DOI: 10.1080/20002297.2022.2079814 -
Journal of Indian Society of... 2023is a Gram-negative anaerobic bacilli. The phenotypic characteristics of the various species of are similar, which often makes it difficult in routine differentiation...
Simultaneous detection and evaluation of , and in subgingival plaque samples of chronic periodontitis and healthy individuals through multiplex polymerase chain reaction.
BACKGROUND
is a Gram-negative anaerobic bacilli. The phenotypic characteristics of the various species of are similar, which often makes it difficult in routine differentiation and identification of all the species.
AIM
The purpose of the study was to detect and compare presence of , and in subgingival plaque samples of chronic periodontitis and healthy individuals.
MATERIALS AND METHODS
Two hundred and thirty-six subjects were considered consisting of chronic periodontitis (128) and healthy (108) individuals. Subgingival plaque sample was collected in reduced transport fluid and analyzed. DNA extraction and polymerase chain reaction (PCR) were performed for genus followed by positive samples were considered for the detection of selected species through multiplex PCR using specific primers.
RESULTS
Out of 236 samples, 94.1% were positive for genus . Out of 222 cases showed the highest number of cases positive (59.5%) followed by (57.2%), (55.4%), and (40.1%). Species were analyzed individually between chronic periodontitis and healthy, , and showed greater positivity in healthy compared to chronic periodontitis. Positivity for was high in chronic periodontitis compared to healthy.
CONCLUSION
The number of positive cases for species, when correlated with clinical parameters showed an increase in mean score for all clinical parameters assessed, suggesting the presence of variation in the prevalence of species and geographic variation do exist in oral microflora. Findings suggest that they can be normal commensals and opportunistic.
PubMed: 37346862
DOI: 10.4103/jisp.jisp_154_22 -
Microorganisms Jun 2021The importance and abundance of strict anaerobic bacteria in the respiratory microbiota of people with cystic fibrosis (PWCF) is now established through studies based on...
The importance and abundance of strict anaerobic bacteria in the respiratory microbiota of people with cystic fibrosis (PWCF) is now established through studies based on high-throughput sequencing or extended-culture methods. In CF respiratory niche, one of the most prevalent anaerobic genera is , and particularly the species The objective of this study was to evaluate the antibiotic susceptibility of this anaerobic species. Fifty isolates of cultured from sputum of 50 PWCF have been included. Antibiotic susceptibility testing was performed using the agar diffusion method. All isolates were susceptible to the following antibiotics: amoxicillin/clavulanic acid, piperacillin/tazobactam, imipenem and metronidazole. A total of 96% of the isolates (48/50) were resistant to amoxicillin (indicating beta-lactamase production), 34% to clindamycin (17/50) and 24% to moxifloxacin (12/50). Moreover, 10% (5/50) were multidrug-resistant. A significant and positive correlation was found between clindamycin resistance and chronic azithromycin administration. This preliminary study on a predominant species of the lung "anaerobiome" shows high percentages of resistance, potentially exacerbated by the initiation of long-term antibiotic therapy in PWCF. The anaerobic resistome characterization, focusing on species rather than genera, is needed in the future to better prevent the emergence of resistance within lung microbiota.
PubMed: 34208093
DOI: 10.3390/microorganisms9061275 -
Microbial Pathogenesis Nov 2023Increasing studies have shown that the imbalance of the respiratory microbial flora is related to the occurrence of COPD, the severity and frequency of exacerbations and...
BACKGROUND
Increasing studies have shown that the imbalance of the respiratory microbial flora is related to the occurrence of COPD, the severity and frequency of exacerbations and mortality.However, it remains unclear how the sputum microbial flora differs during exacerbations in COPD patients manifesting emphysema phenotype, chronic bronchitis with emphysema phenotype and asthma-COPD overlap phenotype.
METHODS
Sputum samples were obtained from 29 COPD patients experiencing acute exacerbations who had not received antibiotics or systemic corticosteroids within the past four weeks.Patients were divided into three groups;emphysema phenotype(E);chronic bronchitis with emphysema phenotype(B+E) and asthma-COPD overlap phenotype(ACO).We utilized metagenomic Next Generation Sequencing (mNGS) technology to analyze the sputum microbial flora in COPD patients with different phenotypes during exacerbations.
RESULTS
There was no significant difference in alpha diversity and beta diversity among three groups.The microbial flora composition was similar in all three groups during exacerbations except for a significant increase in Streptococcus mitis in ACO.Through network analysis,we found Candidatus Saccharibacteria oral taxon TM7x and Fusobacterium necrophorum were the core nodes of the co-occurrence network in ACO and E respectively.They were positively correlated with some species and play a synergistic role.In B+E,Haemophilus pittmaniae and Klebsiella pneumoniae had a synergistic effect.Besides,some species among the three groups play a synergistic or antagonistic role.Through Spearman analysis,we found the relative abundance of Streptococcus mitis was negatively correlated with the number of hospitalizations in the past year(r = -0.410,P = 0.027).We also observed that the relative abundance of Prevotella and Prevotella melaninogenica was negatively correlated with age(r = -0.534,P = 0.003;r = -0.567,P = 0.001),while the relative abundance of Streptococcus oralis and Actinomyces odontolyticus was positively correlated with age(r = 0.570,P = 0.001;r = 0.480,P = 0.008).In addition,the relative abundance of Prevotella melaninogenica was negatively correlated with peripheral blood neutrophil ratio and neutrophil to lymphocyte ratio(r = -0.479,P = 0.009;r = -0.555,P = 0.002),while the relative abundance of Streptococcus sanguinis was positively correlated with peripheral blood neutrophil ratio and neutrophil to lymphocyte ratio (r = 0.450,P = 0.014;r = 0.501,P = 0.006).There was also a significant positive correlation between Oribacterium and blood eosinophil counts(r = 0.491,P = 0.007).
CONCLUSION
Overall,we analyzed the sputum microbiota of COPD patients with different phenotypes and its relationship with clinical indicators, and explored the relationships between microbiota and inflammation in COPD.We hope to alter the prognosis of patients by inhibiting specific bacterial taxa related to inflammation and using guide individualized treatment in the future research.
Topics: Humans; Bronchitis, Chronic; Sputum; Pulmonary Disease, Chronic Obstructive; Phenotype; Asthma; Emphysema; Inflammation
PubMed: 37673353
DOI: 10.1016/j.micpath.2023.106335 -
Journal of Oral Microbiology 2023The current study aimed to test the hypothesis that Parkinson's disease exacerbates periodontitis by altering its microbiome.
AIM
The current study aimed to test the hypothesis that Parkinson's disease exacerbates periodontitis by altering its microbiome.
MATERIALS AND METHODS
Clinical periodontal parameters were recorded. Subgingival samples from healthy controls, periodontitis patients (PD), and Parkinson's patients with periodontitis (PA+PD) were analyzed using the checkerboard DNA-DNA hybridization technique for targeting 40 bacterial species typically associated with periodontal disease and health. Next-generation sequencing (NGS) of the 16S ribosomal RNA gene (V1-V3 regions) was performed to analyze the microbiome comprehensively.
RESULTS
Parkinson's patients had mild-to-moderate motor dysfunctions. Bleeding on probing was significantly increased in the PA+PD group compared to PD ( < 0.05). With checkerboard analysis, PA was associated with increased ( = 0.0062), ( = 0.0439), ( < 0.0001), ( = 0.0002), ( < 0.0001), and ( = 0.0020). ( = 0.0042), ( = 0.0022), ( = 0.0002), ( = 0.0045), ( = 0.0267), ( = 0.0017), ( = 0.0020), and ( = 0.0002) were higher; ( = 0.0072) was lower in deep pockets in the PA+PD compared to PD. ( = 0.0351) and ( = 0.002) were lower; ( = 0.0002), ( = 0065), ( = 0.0151), ( = 0.0141), ( = 0.0057), and ( = 0.0316) were higher in shallow pockets in the PA+PD. Diversity decreased in PD ( = 0.001) and PA+PD ( = 0.026) compared to control, with minimal differences in alpha and beta diversities among PD and PA+PD based on NGS results.
CONCLUSION
These data demonstrated that Parkinson's disease modifies PD-associated subgingival microbiome.
PubMed: 37649970
DOI: 10.1080/20002297.2023.2250650 -
Revista Espanola de Quimioterapia :... Oct 2015Noma is an aggressive orofacial gangrenous pathology that damages hard and soft tissues of the mouth and the face. Throughout the centuries it has been present around... (Review)
Review
Noma is an aggressive orofacial gangrenous pathology that damages hard and soft tissues of the mouth and the face. Throughout the centuries it has been present around the globe, but nowadays it has practically disappeared from developed countries and mainly affects children from the most disadvantaged places, especially in Africa. Noma disease is a multifactorial process; malnutrition, debilitating diseases (bacterial or viral systemic diseases, HIV-associated immunosuppression, etc.) and intraoral infections are some of the factors implied. The characteristic tissue necrosis is produced by a polymicrobial infection. Fusobacterium necrophorum, Prevotella intermedia, Prevotella melaninogenica, Fusobacterium nucleatum, Bacteroides fragilis, Bacillus cereus, Trueperella pyogenes, spyrochetes, etc, are some of the species that have been isolated from the affected areas. Without treatment, noma is lethal in a short period of time, and the patients that survive show severe sequelae that hinder their life and interpersonal relationships. The aim of this paper is to unify the existing information and to promote wider knowledge and awareness among the population.
Topics: Africa; Humans; Neglected Diseases; Noma; Quality of Life; Risk Factors
PubMed: 26437752
DOI: No ID Found -
Journal of Dental Research Jun 2023Dental caries is the most common chronic disease in children that causes negative effects on their health, development, and well-being. Early preventive interventions...
Dental caries is the most common chronic disease in children that causes negative effects on their health, development, and well-being. Early preventive interventions are key to reduce early childhood caries prevalence. An efficient strategy is to provide risk-based targeted prevention; however, this requires an accurate caries risk predictor, which is still lacking for infants before caries onset. We aimed to develop a caries prediction model based on the salivary microbiome of caries-free 1-y-old children. Using a nested case-control design within a prospective cohort study, we selected 30 children based on their caries status at 1-y follow-up (at 2 y old): 10 children who remained caries-free, 10 who developed noncavitated caries, and 10 who developed cavitated caries. Saliva samples collected at baseline before caries onset were analyzed through 16S rRNA gene sequencing. The results of β diversity analysis showed a significant difference in salivary microbiome composition between children who remained caries-free and those who developed cavitated caries at 2 y old (analysis of similarities, Benjamini-Hochberg corrected, = 0.042). The relative abundance of , sp. HMT 215, , and in children who remained caries-free was significantly higher than in children who developed cavitated caries (Wilcoxon rank sum test, = 0.024, 0.040, 0.049, and 0.049, respectively). These taxa were also identified as biomarkers for children who remained caries-free (linear discriminant analysis effect size, linear discriminant analysis score = 3.69, 3.74, 3.53, and 3.46). A machine learning model based on these 4 species distinguished between 1-y-old children who did and did not develop cavitated caries at 2 y old, with an accuracy of 80%, sensitivity of 80%, and specificity of 80% (area under the curve, 0.8; 95% CI, 44.4 to 97.5). Our findings suggest that these salivary microbial biomarkers could assist in predicting future caries in caries-free 1-y-old children and, upon validation, are promising for development into an adjunctive tool for caries risk prediction for prevention and monitoring.
Topics: Infant; Humans; Child; Child, Preschool; Dental Caries; RNA, Ribosomal, 16S; Prospective Studies; Saliva; Microbiota; Biomarkers
PubMed: 36919874
DOI: 10.1177/00220345231152802 -
Respiratory Research Jan 2023Pulmonary Rehabilitation (PR) is one of the most cost-effective therapies for chronic obstructive pulmonary disease (COPD) management. There are, however, people who do...
BACKGROUND
Pulmonary Rehabilitation (PR) is one of the most cost-effective therapies for chronic obstructive pulmonary disease (COPD) management. There are, however, people who do not respond to PR and reasons for non-response are mostly unknown. PR is likely to change the airway microbiota and this could play a role in its responsiveness. In this study we have explored the association between PR effectiveness and specific alterations in oral microbiota and inflammation.
METHODS
A prospective longitudinal study was conducted. Data on exercise capacity, dyspnoea, impact of disease and 418 saliva samples were collected from 76 patients, half of whom participated in a 12-weeks PR programme. Responders and non-responders to PR (dyspnoea, exercise-capacity and impact of disease) were defined based on minimal clinically important differences.
RESULTS
Changes in microbiota, including Prevotella melaninogenica and Streptococcus were observed upon PR. Prevotella, previously found to be depleted in severe COPD, increased during the first month of PR in responders. This increase was negatively correlated with Streptococcus and Lautropia, known to be enriched in severe cases of COPD. Simultaneously, an anti-inflammatory commensal of the respiratory tract, Rothia, correlated strongly and negatively with several pro-inflammatory markers, whose levels were generally boosted by PR. Conversely, in non-responders, the observed decline in Prevotella correlated negatively with Streptococcus and Lautropia whose fluctuations co-occurred with several pro-inflammatory markers.
CONCLUSIONS
PR is associated with changes in oral microbiota. Specifically, PR increases salivary Prevotella melaninogenica and avoids the decline in Rothia and the increase in Streptococcus and Lautropia in responders, which may contribute to the benefits of PR.
Topics: Humans; Prospective Studies; Longitudinal Studies; Pulmonary Disease, Chronic Obstructive; Dyspnea
PubMed: 36698137
DOI: 10.1186/s12931-023-02339-z