High-throughput DNA sequencing of microbiota at interproximal sites.
Conclusion: The microbiota at interproximal regions appears to be specific and stable through time. Potentially pathogenic bacteria may increase caries development risk and gingival inflammation at those sites. PMID: 32002129 [PubMed] (Source: Journal of Oral Microbiology)
Source: Journal of Oral Microbiology - February 2, 2020 Category: Microbiology Tags: J Oral Microbiol Source Type: research

Inhibitory and preventive effects of Lactobacillus plantarum FB-T9 on dental caries in rats.
This study aimed to determine the inhibitory effect of Lactobacillus plantarum FB-T9 on S. mutans biofilm formation in vitro and on the prevention and treatment of dental caries in rats. During in vitro experiments, FB-T9 exhibited good bacteriostatic ability in a plate competition assay. This strain also significantly reduced the biomass and viability of S. mutans biofilms and induced structural damage during the early (6 h), middle (12 h) and late (24 h) stages of biofilm formation. In a 70-day in vivo experiment, FB-T9 significantly reduced the levels of S. mutans on the dental surfaces of rats by more than 2 orders of ...
Source: Journal of Oral Microbiology - February 2, 2020 Category: Microbiology Tags: J Oral Microbiol Source Type: research

Integrated hypothesis of dental caries and periodontal diseases.
Authors: Nyvad B, Takahashi N Abstract This review considers an integrated hypothesis of dental caries and periodontal diseases that builds on theoretical ecological principles. The backbone of the hypothesis is based on the dynamic stability stage of the oral microbiota, at which intrinsic (mainly saliva and gingival crevicular fluid) and bacterial (mainly metabolic) resilience factors maintain ecological dynamic stability, compatible with clinical health. However, loss of intrinsic resilience factors and/or prolonged changes in the availability of microbial metabolic substrates may shift the ecological balance of...
Source: Journal of Oral Microbiology - February 2, 2020 Category: Microbiology Tags: J Oral Microbiol Source Type: research

Role of EphA2 in host defense against oro-pharyngeal candidiasis.
Authors: Olsen I Abstract Oral defense should be able to sense the burden of, and distinguish between fungal commensals and pathogens, so that an adequate inflammatory response can be set up. Recently, Ephrin type-A receptor 2 (EphA2) was identified on oral epithelial cells and neutrophils that recognizes Candida albicans and induces adaptive protective host responses against this organism. The studies have increased our knowledge of how epithelial cells and neutrophils contribute to host defense against oral yeast infection. PMID: 32002132 [PubMed] (Source: Journal of Oral Microbiology)
Source: Journal of Oral Microbiology - February 2, 2020 Category: Microbiology Tags: J Oral Microbiol Source Type: research

Is there a link between genetic defects in the complement cascade and Porphyromonas gingivalis in Alzheimer's disease?
Authors: Olsen I, Singhrao SK Abstract Defects, as determined by Genome-Wide Association Studies (GWAS), in the complement cascade of innate immunity have been suggested to play a key role in Alzheimer's disease (AD). These defective genes encode sub-component 1s (C1s), complement receptor 1, complement component 9, and clusterin, a fluid-phase regulatory protein. A dysregulated complement cascade has been shown to relate to cell activation, defective complement mediated clearance and possible cognitive decline in AD patients. Porphyromonas gingivalis, a putative keystone pathogen of periodontal disease, has been r...
Source: Journal of Oral Microbiology - January 2, 2020 Category: Microbiology Tags: J Oral Microbiol Source Type: research

Shared detection of Porphyromonas gingivalis in cohabiting family members: a systematic review and meta-analysis.
Conclusion: Pooled results suggest that the likelihood of detecting P.gingivalis within within family members is moderately frequent. Personalized periodontal screening and prevention may consider intra-familial co-occurrence of P.gingivalis as feasible. PMID: 31893015 [PubMed] (Source: Journal of Oral Microbiology)
Source: Journal of Oral Microbiology - January 2, 2020 Category: Microbiology Tags: J Oral Microbiol Source Type: research

Evaluating the relationship between acidogenicity and acid tolerance for oral streptococci from children with or without a history of caries.
Conclusion: An ability to grow on acid agar below pH 5.0 is best aligned with strong acidogenicity and best able to distinguish between subjects with differing caries histories. PMID: 31893016 [PubMed] (Source: Journal of Oral Microbiology)
Source: Journal of Oral Microbiology - January 2, 2020 Category: Microbiology Tags: J Oral Microbiol Source Type: research

Protozoans in subgingival biofilm: clinical and bacterial associated factors and impact of scaling and root planing treatment.
Conclusions: Protozoans were associated with some clinical parameters and/or periodontopathogens in patients with periodontitis. PMID: 31893017 [PubMed] (Source: Journal of Oral Microbiology)
Source: Journal of Oral Microbiology - January 2, 2020 Category: Microbiology Tags: J Oral Microbiol Source Type: research

Salivary concentrations of macrophage activation-related chemokines are influenced by non-surgical periodontal treatment: a 12-week follow-up study.
Conclusions: Periodontal treatment impacts salivary concentrations of MCP-2, MDC and MIP-1α, which correlate with the abundance of specific periodontitis-associated bacteria. This indicates that these chemokines reflect periodontal status and possess potential in illustrating a response to treatment. PMID: 31893018 [PubMed] (Source: Journal of Oral Microbiology)
Source: Journal of Oral Microbiology - January 2, 2020 Category: Microbiology Tags: J Oral Microbiol Source Type: research

Oral microbiota and autism spectrum disorder (ASD).
Authors: Olsen I, Hicks SD Abstract Autism spectrum disorder (ASD) is associated with several oropharyngeal abnormalities, including dysbiosis in the oral microbiota. Since the oral cavity is the start of the gastrointestinal tract, this strengthens and extends the notion of a microbial gut-brain axis in ASD and even raises the question whether a microbial oral-brain axis exists. It is clear that oral bacteria can find their way to the brain through a number of pathways following routine dental procedures. A connection between the oral microbiota and a number of other brain disorders has been reported. As the evide...
Source: Journal of Oral Microbiology - January 2, 2020 Category: Microbiology Tags: J Oral Microbiol Source Type: research

Dual-species biofilms of Streptococcus mutans and Candida albicans exhibit more biomass and are mutually beneficial compared with single-species biofilms.
Authors: Lobo CIV, Rinaldi TB, Christiano CMS, De Sales Leite L, Barbugli PA, Klein MI Abstract Background: Streptococcus mutans (Sm) and Candida albicans (Ca) are found in biofilms of early childhood caries. Objective: To characterize in vitro dual- and single-species biofilms of Sm and Ca formed on saliva-coated hydroxyapatite discs in the presence of sucrose. Design: Evaluation of biofilms included biochemical [biomass, proteins, matrix's water-soluble (WSP) and alkali-soluble (ASP) polysaccharides, microbiological, 3D structure, gene expression, and stress tolerance analyses. Results: Biomass and proteins were ...
Source: Journal of Oral Microbiology - November 6, 2019 Category: Microbiology Tags: J Oral Microbiol Source Type: research

Effect of nicotine on biofilm formation of Streptococcus mutans isolates from smoking and non-smoking subjects.
This study was conducted using 60 S. mutans isolates with three S. mutans isolates collected from oral washes of ten smoking subjects and ten from non-smoking subjects. Biofilm was formed by culturing each S. mutans strain (10 μl) in 190 μl of TSB supplemented with 1% sucrose (TSBS) containing 0, 0.25, 0.5, 1.0, 2.0, 4.0, 8.0, 16.0, and 32.0 mg/ml of nicotine for 24 h in 5% CO2 at 37°C in 96 well microtiter plates. The absorbance values of biofilm were measured at 490 nm in a microplate spectrophotometer. Results: There was a significant effect (p-value
Source: Journal of Oral Microbiology - September 27, 2019 Category: Microbiology Tags: J Oral Microbiol Source Type: research

Composition and maternal origin of the neonatal oral cavity microbiota.
Conclusion: The neonatal oral cavity microbiota is not significantly modulated by the birth canal or maternal oral microbiota but displays clear associations with microbes in the placenta. These results suggest that the neonatal oral microbiota may have a prenatal origin. PMID: 31528268 [PubMed] (Source: Journal of Oral Microbiology)
Source: Journal of Oral Microbiology - September 20, 2019 Category: Microbiology Tags: J Oral Microbiol Source Type: research

Sex-specific differences in the salivary microbiome of caries-active children.
Conclusion: We have found the acid-generating, cariogenic Lactococcus lactis to be much more abundant in caries-active girls than caries-active boys, indicating that this microorganism may play a more significant role in shaping the cariogenic microbiome in girls. In addition, in caries-active girls, Alloprevotella species HOT 473 was the only species that exhibited both significant sex differences (4.4-fold difference; p=0.0003) as well as high abundance in numbers (1.85% of the total microbial population). PMID: 31497256 [PubMed] (Source: Journal of Oral Microbiology)
Source: Journal of Oral Microbiology - September 11, 2019 Category: Microbiology Tags: J Oral Microbiol Source Type: research

Metaproteomics analysis of microbial diversity of human saliva and tongue dorsum in young healthy individuals.
Conclusion: Even if the microbial communities of saliva and tongue dorsum showed a strong similarity based on identified protein functions and deduced bacterial composition, certain specific characteristics were observed. Both microbiomes exhibit a great diversity with seven genera being most abundant. PMID: 31497257 [PubMed] (Source: Journal of Oral Microbiology)
Source: Journal of Oral Microbiology - September 11, 2019 Category: Microbiology Tags: J Oral Microbiol Source Type: research

Next-generation sequencing of whole saliva from patients with primary Sj ögren's syndrome and non-Sjögren's sicca reveals comparable salivary microbiota.
Conclusion: The salivary microbiota and oral health status, as well as salivary flow rate in patients with pSS resemble that of non-pSS patients. Our findings indicate that changes in the salivary microbiota do not appear to be determined by the disease entity pSS itself. PMID: 31497258 [PubMed] (Source: Journal of Oral Microbiology)
Source: Journal of Oral Microbiology - September 11, 2019 Category: Microbiology Tags: J Oral Microbiol Source Type: research

Mixed aerobic-anaerobic incubation conditions induce proteolytic activity from in vitro salivary biofilms.
Authors: Cleaver LM, Moazzez R, Carpenter GH Abstract Oral biofilms have not been studied using both metabolome and protein profiling concurrently. Bacteria produce proteases that lead to degradation of functional salivary proteins. The novel protocol described here allows for complete characterisation of in vitro oral biofilms, including proteolytic, metabolic, and microbiome analysis. Biofilms were grown on hydroxyapatite discs from whole mouth saliva, using sterilised saliva as a growth-medium, in different growth environments. Salivary protein degradation was assessed from spent saliva ...
Source: Journal of Oral Microbiology - September 7, 2019 Category: Microbiology Tags: J Oral Microbiol Source Type: research

The prevalence and impact of lysogeny among oral isolates of Enterococcus faecalis.
Authors: Stevens RH, Zhang H, Sedgley C, Bergman A, Manda AR Abstract Bacterial phenotypic properties are frequently influenced by the uptake of extrachromosomal genetic elements, such as plasmids and bacteriophage genomes. Such modifications can result in enhanced pathogenicity due to toxin production, increased toxin release, altered antigenicity, and resistance to antibiotics. In the case of bacteriophages, the phage genome can stably integrate into the bacterial chromosome as a prophage, to produce a lysogenic cell. Oral enterococcal strains have been isolated from subgingival plaque and the root canals of endo...
Source: Journal of Oral Microbiology - September 7, 2019 Category: Microbiology Tags: J Oral Microbiol Source Type: research

Toothbrushes may convey bacteria to the cystic fibrosis lower airways.
Conclusion: Toothbrushes may be sources of oral contamination and might act as reservoirs favoring transmission of potentially pathogenic microorganisms from the environment to the oral cavity and eventually to the LAW. Oral hygiene and toothbrush care are important strategies to prevent CF lung infections. PMID: 31489126 [PubMed] (Source: Journal of Oral Microbiology)
Source: Journal of Oral Microbiology - September 7, 2019 Category: Microbiology Tags: J Oral Microbiol Source Type: research

Intraoral appliances for in situ oral biofilm growth: a systematic review.
Conclusions: No uniformly superior method for collecting AGOB could be discerned. NGS platforms are preferable for AGOB analyses. PMID: 31489127 [PubMed] (Source: Journal of Oral Microbiology)
Source: Journal of Oral Microbiology - September 7, 2019 Category: Microbiology Tags: J Oral Microbiol Source Type: research

Oral microbiome and obesity in a large study of low-income and African-American populations.
Authors: Yang Y, Cai Q, Zheng W, Steinwandel M, Blot WJ, Shu XO, Long J Abstract Few studies have evaluated the relationship of oral microbiome with obesity. We investigated the oral microbiome among 647 obese and 969 non-obese individuals from the Southern Community Cohort Study, through 16S rRNA gene sequencing in mouth rinse samples. We first investigated 16 taxa in two probiotic genera, Bifidobacterium and Lactobacillus. Among them, eight showed nominal associations with obesity (P
Source: Journal of Oral Microbiology - September 7, 2019 Category: Microbiology Tags: J Oral Microbiol Source Type: research

Porphyromonas gingivalis in saliva associates with chronic and aggressive periodontitis.
Authors: Damgaard C, Danielsen AK, Enevold C, Massarenti L, Nielsen CH, Holmstrup P, Belstrøm D Abstract Objective: To characterize the salivary microbiota of patients with aggressive periodontitis, patients with chronica periodontitis and orally healthy individuals. Methods: A total of 81 unstimulated saliva samples from aggressive periodontitis patients (n = 31), chronic periodontitis patients (n = 25), and orally healthy controls (n = 25) were examined. The V1-V3 region of the 16S rDNA gene was sequenced with Illumina® MiSeqTM, and sequences were annotated to the expanded Human Oral Microbiome Databas...
Source: Journal of Oral Microbiology - September 7, 2019 Category: Microbiology Tags: J Oral Microbiol Source Type: research

Detection and expression analysis of tet(B) in Streptococcus oralis.
In this study, tet(B) was detected in two clinical Streptococcus oralis strains isolated from the gingival sulci of two subjects. In both cases, the gene was completely sequenced, yielding 100% shared identity and coverage with other previously published sequences of tet(B). Moreover, we studied the expression of tet(B) using RT-qPCR in the isolates grown with and without tetracycline, detecting constitutive expression in only one of the isolates, with no signs of expression in the other one. This is the first time that the presence and expression of the tet(B) gene has been confirmed in Gram-positive bacteria, which highl...
Source: Journal of Oral Microbiology - August 28, 2019 Category: Microbiology Tags: J Oral Microbiol Source Type: research

Staphylococcus aureus induces COX-2-dependent proliferation and malignant transformation in oral keratinocytes.
Authors: Wang Y, Liu S, Li B, Jiang Y, Zhou X, Chen J, Li M, Ren B, Peng X, Zhou X, Cheng L Abstract The COX-2/PGE2 axis can play roles in mediating the progression of tumor. COX-2 induction was observed in oral cancer. In our previous study, we found Staphylococcus aureus, a pathogen prevalent in oral cancer, can activate the COX-2/PGE2 pathway in human oral keratinocyte (HOK) cells. Here, we investigated the proliferation of HOK cells affected by COX-2 induction and the role of COX-2 induction in the malignant transformation of HOK cells. We found S. aureus was able to facilitate HOK...
Source: Journal of Oral Microbiology - August 28, 2019 Category: Microbiology Tags: J Oral Microbiol Source Type: research

Susceptibility of oral bacteria to antibacterial photodynamic therapy.
Authors: Kang SM, Jung HI, Kim BI Abstract Effective methods for managing the oral microbiome are necessary to ensure not only the oral but also the systemic health of a human body. The purpose of this study was to determine the sensitivity of four photosensitizers (PSs) to blue light in six representative oral bacterial species that cause intraoral diseases. The following six strains were investigated: Actinomyces israelii, Enterococcus faecium, Fusobacterium nucleatum, Lactobacillus gasseri, Streptococcus mutans, Veillonella parvula. PS stock solutions (1 mg/ml) were prepared by dissolvin...
Source: Journal of Oral Microbiology - August 28, 2019 Category: Microbiology Tags: J Oral Microbiol Source Type: research

Porphyromonas gingivalis and its CRISPR-Cas system.
Authors: Chen T, Olsen I Abstract The clustered regularly interspaced short palindromic repeats (CRISPRs) and their associated proteins (Cas) are immune systems in prokaryotes present in most Bacteria and Archaea. They provide adaptive immunity against foreign elements such as bacteriophages/viruses, plasmids and transposons. During immunization a small sequence of foreign DNA, a so-called spacer is integrated into the CRISPR locus in the host cell. Spacers are then transcribed into small RNA guides that direct cleavage of foreign DNA by Cas nucleases. Immunization through spacer acquisition is transferred vertical...
Source: Journal of Oral Microbiology - July 16, 2019 Category: Microbiology Tags: J Oral Microbiol Source Type: research

Subgingival microbiome of experimental gingivitis: shifts associated with the use of chlorhexidine and N-acetyl cysteine mouthwashes.
This study aimed to demonstrate subgingival microbial changes associated with development, prevention, and treatment of experimental gingivitis using chlorhexidine (CHX) and N-acetylcysteine (NAC) mouthwashes. This randomized clinical trial comprised two parts: a 3-week prevention sub-study in which 30 study subjects were equally assigned to either mouthwash or placebo while developing experimental gingivitis; followed by a 2-week treatment sub-study in which 20 subjects with experimental gingivitis were assigned to either mouthwash. Subgingival samples were collected at the beginning and end of each sub-study for microbia...
Source: Journal of Oral Microbiology - July 6, 2019 Category: Microbiology Tags: J Oral Microbiol Source Type: research

Killing mechanism of bacteria within multi-species biofilm by blue light.
Conclusion: Blue-light has an impact on the bacterial composition and viability of the multispecies biofilm. The phototoxic effect of blue light on P. gingivalis in biofilm was induced directly and on F. nucleatum via ROS mediators of the paracrine pathway. This phenomenon may lead to a novel approach for 'replacement therapy,' resulting in a less periodonto-pathogenic biofilm. PMID: 31275529 [PubMed] (Source: Journal of Oral Microbiology)
Source: Journal of Oral Microbiology - July 6, 2019 Category: Microbiology Tags: J Oral Microbiol Source Type: research

Sexually transmitted infections in oral cavity lesions: Human papillomavirus, Chlamydia trachomatis, and Herpes simplex virus.
Conclusion: This report is the first contribution to the identification and genotype characterization of HPV in a scenario little studied in our area, and it also contributes to improving our understanding on sexually transmitted infectious agents and their associations with the oral cavity. Besides, we detect the presence of C. trachomatis and HSV and co-infection with HPV in the oral cavity, which they should be taken into account for diagnostic and treatment purposes. PMID: 31275530 [PubMed] (Source: Journal of Oral Microbiology)
Source: Journal of Oral Microbiology - July 6, 2019 Category: Microbiology Tags: J Oral Microbiol Source Type: research

Bacterial biofilm composition in healthy subjects with and without caries experience.
Conclusion: The analysis of the oral microbiome of subjects with and without caries experience indicates specific differences. With the presence of Corynebacterium and Fusobacterium subjects without caries experience exhibited more frequently organisms that are considered to be main actors in structural plaque formation and integration. The abundance of Corynebacterium might be interpreted as a signature for dental health. PMID: 31275531 [PubMed] (Source: Journal of Oral Microbiology)
Source: Journal of Oral Microbiology - July 6, 2019 Category: Microbiology Tags: J Oral Microbiol Source Type: research

H2S mediates increased interleukin (IL)-1 β and IL-18 production in leukocytes from patients with periodontitis.
H2S mediates increased interleukin (IL)-1β and IL-18 production in leukocytes from patients with periodontitis. J Oral Microbiol. 2019;11(1):1617015 Authors: Basic A, Serino G, Leonhardt Å, Dahlén G Abstract Background: The mechanisms involved in the interplay between the bacteria and the host cells in periodontitis are not fully understood. Aim: To investigate the effect of the bacterial metabolite H2S on the pro-inflammatory cytokines interleukin (IL)-1β and IL-18 from periodontitis patients and healthy controls, and to evaluate the composition of the subgingival microbiota wit...
Source: Journal of Oral Microbiology - June 6, 2019 Category: Microbiology Tags: J Oral Microbiol Source Type: research

Inactivation of Streptococcus mutans genes lytST and dltAD impairs its pathogenicity in vivo.
Conclusions: Altogether, these findings indicate that inactivation of lytST and dltAD impaired S. mutans cariogenicity and virulence in vivo. PMID: 31143407 [PubMed] (Source: Journal of Oral Microbiology)
Source: Journal of Oral Microbiology - June 1, 2019 Category: Microbiology Tags: J Oral Microbiol Source Type: research

Deep sequencing of biofilm microbiomes on dental composite materials.
Conclusion: We found that the oral microbiome showed an increased richness when grown on various composites compared to BE in vitro, but otherwise changed only slightly independent of the in vivo or in vitro condition. Our new ex vivo biofilm model might be useful for pre-clinical testing of preventive strategies. PMID: 31143408 [PubMed] (Source: Journal of Oral Microbiology)
Source: Journal of Oral Microbiology - June 1, 2019 Category: Microbiology Tags: J Oral Microbiol Source Type: research

Development of an in vitro system to study oral biofilms in real time through impedance technology: validation and potential applications.
Conclusions: We therefore propose the system as a valid in vitro model to study oral biofilm dynamics, including their susceptibility to antibiotics, antiseptics or anti-adhesive compounds. PMID: 31105900 [PubMed] (Source: Journal of Oral Microbiology)
Source: Journal of Oral Microbiology - May 22, 2019 Category: Microbiology Tags: J Oral Microbiol Source Type: research

β-Hemolytic Streptococcus anginosus subsp. anginosus causes streptolysin S-dependent cytotoxicity to human cell culture lines in vitro.
Conclusion: The results from this study suggest that the SLS produced from β-SAA might indicate the cytotoxic potential similar to that of the SLS from S. pyogenes and the SLS-producing β-SAA would be recognized as "a wolf in sheep's clothing" More attention will be paid to the pathogenicity of β-hemolytic Anginosus group streptococci. PMID: 31105901 [PubMed] (Source: Journal of Oral Microbiology)
Source: Journal of Oral Microbiology - May 22, 2019 Category: Microbiology Tags: J Oral Microbiol Source Type: research

An in vitro and in vivo study of plasma treatment effects on oral biofilms.
The objective of this study is to investigate the treatment effects of non-thermal atmospheric gas plasmas on oral biofilm formation and recovery under in vitro and in vivo conditions. Streptococcus mutans biofilms, a significant contributor to tooth decay, were cultured and treated by plasma. It was found that plasma treatment not only significantly reduced the in vitro biofilms, but also increased the metabolic activity of the bacteria in the biofilms. As compared with untreated control group, the cell metabolic activity, as measured by MTT assay, increased by 273%, and the aconitase activity increased by 446% for the pl...
Source: Journal of Oral Microbiology - May 10, 2019 Category: Microbiology Tags: J Oral Microbiol Source Type: research

Effect of reduced nutritional supply on the metabolic activity and survival of cariogenic bacteria in vitro.
Authors: Ganas P, Schwendicke F Abstract Sealed cariogenic bacteria are deprived from dietary carbohydrate, but could be provided with nutrients by pulpal fluids, with adaptive strain-specific activities being possible. We investigated survival and metabolic activity of the cariogenic bacteria Streptococcus sobrinus, Actinomyces naeslundii and Lactobacillus rhamnosus in different carbohydrate-limited media without carbon source (CLM), or containing glucose (CLM-G), albumin (CLM-A), or α1-acid glycoprotein (CLM-AGP) in vitro. Bacterial metabolite concentrations (lactate, pyruvate, oxaloacetate, citrate, acetat...
Source: Journal of Oral Microbiology - May 10, 2019 Category: Microbiology Tags: J Oral Microbiol Source Type: research

Association of the oral microbiome with the progression of impaired fasting glucose in a Chinese elderly population.
Conclusions: These results suggest that dysbiosis of the oral microbiota may be a typical feature of hyperglycemia and might also contribute to disease aggravation in the progression of hyperglycemias. PMID: 31069021 [PubMed] (Source: Journal of Oral Microbiology)
Source: Journal of Oral Microbiology - May 10, 2019 Category: Microbiology Tags: J Oral Microbiol Source Type: research

Serotype b of Aggregatibacter actinomycetemcomitans triggers pro-inflammatory responses and amyloid beta secretion in hippocampal cells: a novel link between periodontitis and Alzheimer ´s disease?
Conclusion: Altogether, our results show that treatment with serotype b-LPS triggers the secretion of proinflammatory cytokines by microglia, induces neurite shrinking, and increases the extracellular Aβ1-42 levels, all features strongly associated with the etiology of AD. PMID: 31044031 [PubMed] (Source: Journal of Oral Microbiology)
Source: Journal of Oral Microbiology - May 5, 2019 Category: Microbiology Tags: J Oral Microbiol Source Type: research

Incidence and spectrum of yeast species isolated from the oral cavity of Iranian patients suffering from hematological malignancies.
Authors: Arastehfar A, Daneshnia F, Farahyar S, Fang W, Salimi M, Salehi M, Hagen F, Weihua P, Roudbary M, Boekhout T Abstract Background: Oral candidiasis (OC) has a profound effect on the life quality of immunocompromised patients, such as those undergoing chemotherapy. Objective: Systematic investigation of clinical outcome and microbiological features of yeast isolates recovered from the oral cavity of 150 Iranian patients with hematological malignancies. Design: MALDI-TOF MS, 21-plex PCR, and rDNA sequencing were used for identification. Antifungal susceptibility testing (broth mi...
Source: Journal of Oral Microbiology - May 5, 2019 Category: Microbiology Tags: J Oral Microbiol Source Type: research

Characterization of the phosphotransacetylase-acetate kinase pathway for ATP production in Porphyromonas gingivalis.
Authors: Yoshida Y, Sato M, Nonaka T, Hasegawa Y, Kezuka Y Abstract Acetyl phosphate (AcP) is generally produced from acetyl coenzyme A by phosphotransacetylase (Pta), and subsequent reaction with ADP, catalyzed by acetate kinase (Ack), produces ATP. The mechanism of ATP production in Porphyromonas gingivalis is poorly understood. The aim of this study was to explore the molecular basis of the Pta-Ack pathway in this microorganism. Pta and Ack from P. gingivalis ATCC 33277 were enzymatically and structurally characterized. Structural and mutational analyses suggest that Pta is a dimer with two substrate-binding sit...
Source: Journal of Oral Microbiology - April 23, 2019 Category: Microbiology Tags: J Oral Microbiol Source Type: research

Metatranscriptomic analysis of an in vitro biofilm model reveals strain-specific interactions among multiple bacterial species.
Conclusion: We report here the existence of strain-specific interactions in subgingival plaque, which may enhance our understanding of periodontal micro-ecology and facilitate the development of improved plaque control strategies. PMID: 31007867 [PubMed] (Source: Journal of Oral Microbiology)
Source: Journal of Oral Microbiology - April 23, 2019 Category: Microbiology Tags: J Oral Microbiol Source Type: research

Analysis of oral bacterial communities: comparison of HOMINGS with a tree-based approach implemented in QIIME.
Conclusions: A direct comparison demonstrates that HOMINGS is largely equivalent to the tree-based approach as implemented here. PMID: 30988892 [PubMed] (Source: Journal of Oral Microbiology)
Source: Journal of Oral Microbiology - April 18, 2019 Category: Microbiology Tags: J Oral Microbiol Source Type: research

Can oral bacteria affect the microbiome of the gut?
Authors: Olsen I, Yamazaki K Abstract Oral bacteria spreading through the body have been associated with a number of systemic diseases. The gut is no exception. Studies in animals and man have indicated that oral bacteria can translocate to the gut and change its microbiota and possibly immune defense. The ectopic displacement of oral bacteria particularly occurs in severe systemic diseases, but also in patients with "chronic" periodontitis. Thus, Porphyromonas gingivalis, which creates dysbiosis in the subgingival microbiota and immune defense, may also cause dysregulation in the gut. A dysbiotic gut mic...
Source: Journal of Oral Microbiology - March 27, 2019 Category: Microbiology Tags: J Oral Microbiol Source Type: research

Caries-associated oral microbiome in head and neck cancer radiation patients: a longitudinal study.
Authors: Mougeot JC, Stevens CB, Almon KG, Paster BJ, Lalla RV, Brennan MT, Mougeot FB Abstract Head and neck cancer (HNC) therapy often leads to caries development. Our goal was to characterize the oral microbiome of HNC patients who underwent radiation therapy (RT) at baseline (T0), and 6 (T6) and 18 (T18) months post-RT, and to determine if there was a relationship with increased caries. HOMINGS was used to determine the relative abundance (RA) of>600 bacterial species in oral samples of 31 HNC patients. The DMFS score was used to define patient groups with tooth decay increase (DMFS[+]) or no increase (...
Source: Journal of Oral Microbiology - March 21, 2019 Category: Microbiology Tags: J Oral Microbiol Source Type: research

Diversity and functional analysis of salivary microflora of Indian Antarctic expeditionaries.
Conclusion: Study suggests that understanding the compositional and functional differences in the oral microbiota of Antarctic expedition members, can lay the foundation to relate these differences to their health status. It will further demonstrate the need for providing improved management during ship voyage and stay in Antarctica. PMID: 30834068 [PubMed] (Source: Journal of Oral Microbiology)
Source: Journal of Oral Microbiology - March 7, 2019 Category: Microbiology Tags: J Oral Microbiol Source Type: research

Assessing the role of Porphyromonas gingivalis in periodontitis to determine a causative relationship with Alzheimer's disease.
Authors: Singhrao SK, Olsen I Abstract Chronic periodontitis of 10 years' duration is reported to become a twofold risk factor for the development of Alzheimer's disease (AD). Periodontitis is modifiable, and this fits with the current action plan for preventing AD. However, until periodontitis, becomes acknowledged as a firm risk factor for AD, this risk will continue. Here, we put forward our own argument based on the current literature for in vivo infection-mediated periodontal disease models supporting the antimicrobial protection hypothesis of AD and interventional studies supporting the causal links. Oral inf...
Source: Journal of Oral Microbiology - February 10, 2019 Category: Microbiology Tags: J Oral Microbiol Source Type: research

Tongue coating microbiome data distinguish patients with pancreatic head cancer from healthy controls.
Conclusions: These findings identified the microbiota dysbiosis of the tongue coat in PHC patients, and provide insight into the association between the human microbiome and pancreatic cancer. PMID: 30728915 [PubMed] (Source: Journal of Oral Microbiology)
Source: Journal of Oral Microbiology - February 10, 2019 Category: Microbiology Tags: J Oral Microbiol Source Type: research

Fusobacterium spp. target human CEACAM1 via the trimeric autotransporter adhesin CbpF.
Authors: Brewer ML, Dymock D, Brady RL, Singer BB, Virji M, Hill DJ Abstract Neisseria meningitidis, Haemophilus influenzae, and Moraxella catarrhalis are pathogenic bacteria adapted to reside on human respiratory mucosal epithelia. One common feature of these species is their ability to target members of the carcinoembryonic antigen-related cell adhesion molecule (CEACAM) family, especially CEACAM1, which is achieved via structurally distinct ligands expressed by each species. Beside respiratory epithelial cells, cells at the dentogingival junction express high levels of CEACAM1. It is possible that bacterial spec...
Source: Journal of Oral Microbiology - February 7, 2019 Category: Microbiology Tags: J Oral Microbiol Source Type: research

Metagenome sequencing-based strain-level and functional characterization of supragingival microbiome associated with dental caries in children.
Authors: Al-Hebshi NN, Baraniya D, Chen T, Hill J, Puri S, Tellez M, Hasan NA, Colwell RR, Ismail A Abstract Studies of the microbiome associated with dental caries have largely relied on 16S rRNA sequence analysis, which is associated with PCR biases, low taxonomic resolution, and inability to accurately study functions. Here, we employed whole metagenome shotgun sequencing, coupled with high-resolution analysis algorithm, to analyze supragingival microbiomes from 30 children with or without dental caries. A total of 726 bacterial strains belonging to 406 species, in addition to 34 bacteriophages were identified. ...
Source: Journal of Oral Microbiology - January 25, 2019 Category: Microbiology Tags: J Oral Microbiol Source Type: research