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Frontiers in Microbiology 2021The self-produced matrix of biofilms, consisting of extracellular polymeric substances, plays an important role in biofilm adhesion to surfaces and the structural...
The self-produced matrix of biofilms, consisting of extracellular polymeric substances, plays an important role in biofilm adhesion to surfaces and the structural integrity of biofilms. In dentistry, biofilms cause multiple diseases such as caries, periodontitis, and pulpitis. Disruption of these biofilms adhering to dental hard tissues may pose a major challenge since biofilms show higher tolerance to antimicrobials and antibiotics than planktonic cells. In this study, the effect of low concentrations of chlorhexidine (CHX) on enzyme-treated multispecies oral biofilm was investigated in an model. Six-species biofilms were enzymatically treated by anaerobic growth in a medium containing DNase I and proteinase K. Biofilms were exposed to a low concentration of CHX at defined time points. After 64h, biofilms were either harvested and quantified by cultural analyses or stained for confocal laser scanning microscopy (CLSM) analyses using either Live/Dead kit or different fluorescent dyes. A mixture of YoPro1 and SYTOX Green, Fluorescent Brightener 28 (Calcofluor), and SYPRO Ruby Protein Gel Stain was used to stain total DNA, exopolysaccharides, and extracellular proteins, respectively. Extracellular DNA (eDNA) was visualized an indirect immunofluorescence assay (Mouse anti-DNA IgG, Goat anti-Mouse IgG, Streptavidin-Cy3). Overall, the total colony-forming units significantly decreased after combined treatment with a low concentration of CHX and enzymes compared to the group treated with CHX alone (<0.001). These findings also apply to five species individually ( and ) occurring in the biofilms, with being the only exception. Furthermore, CLSM images showed less dense biofilms and a reduction in cell numbers after combined treatment compared to the group without enzymes. The combination of enzymes capable of disturbing the matrix integrity with antimicrobial agents thus appears to be a promising approach for biofilm disruption and killing.
PubMed: 34650542
DOI: 10.3389/fmicb.2021.741863 -
Saudi Journal of Gastroenterology :... 2023The results of this study provide an overview of the variations in microbiota diversity present in Saudi IBD patients compared to healthy controls.
CONCLUSIONS
The results of this study provide an overview of the variations in microbiota diversity present in Saudi IBD patients compared to healthy controls.
RESULTS
The key finding was three negative bacterial biomarkers, Paraprevotellaceae, the Muribaculaceae families of Bacteroidetes phylum, and the Leuconostocaceae family of Firmicutes phylum, which had a higher relative abundance in healthy individuals compared to IBD patients. It was also found that primary microbiota signatures at certain genera and species levels, including Prevotella copri, Bifidobacterium adolescentis, Ruminococcus callidus, Coprococcus sp., Ruminococcus gnavus, Dorea formicigenerans, Leuconostoc, Dialister, Catenibacterium, Eubacterium biforme, and Lactobacillus mucosae, were absent in almost all IBD patients, while Veillonella dispar was absent in all healthy individuals.
METHODS
After obtaining an informed consent, fecal samples were collected from 11 participants with IBD (patients) and 10 healthy individuals (controls). The bacterial components of the microbial population were identified by next-generation sequencing of partial 16S rRNA. Statistically significant dissimilarities were observed between samples for all metrics.
BACKGROUND
Inflammatory bowel disease (IBD) is a chronic intestinal inflammatory condition attributed to a complex interaction between imbalances in the gut microbiome, environmental conditions, and a deregulated immune response. The aim of the study was to investigate the composition of the gut microbiome of Saudi patients with IBD.
Topics: Humans; Gastrointestinal Microbiome; Pilot Projects; Saudi Arabia; RNA, Ribosomal, 16S; Inflammatory Bowel Diseases; Feces
PubMed: 36695274
DOI: 10.4103/sjg.sjg_368_22 -
BMC Oral Health Apr 2021Excessive biofilm formation on surfaces in the oral cavity is amongst the main reasons for severe infection development like periodontitis and peri-implantitis....
BACKGROUND
Excessive biofilm formation on surfaces in the oral cavity is amongst the main reasons for severe infection development like periodontitis and peri-implantitis. Mechanical biofilm removal as well as the use of adjuvant antiseptics supports the prevention of pathogenic biofilm formation. Recently, the antibacterial effect of the oral care product REPHA-OS, based on medicinal plant extracts and essential oils, has been demonstrated on oral pathogens grown on agar plates. In the present study, the effectiveness of the product on medical relevant oral biofilm development should be demonstrated for the first time.
METHODS
An established in vitro oral multispecies biofilm, composed of Streptococcus oralis, Actinomyces naeslundii, Veillonella dispar and Porphyromonas gingivalis, was used to analyze the antibacterial effect of different REPHA-OS concentrations on planktonic bacteria, biofilm formation and mature biofilms. It was quantified using metabolic activity assays and live/dead fluorescence staining combined with three-dimensional confocal laser-scanning microscopy. Additionally, effects on species distribution inside the biofilm were assessed by means of quantitative real-time PCR.
RESULTS
REPHA-OS showed statistically significant antimicrobial effects on all stages of biofilm development: a minimal inhibitory concentration of 5% could be detected for both, for planktonic bacteria and for biofilm formation. Interestingly, only a slightly higher concentration of 10% was necessary to completely kill all bacteria in mature biofilms also. In contrast, an influence on the biofilm matrix or the species distribution could not be observed. The effect could be attributed to the herbal ingredients, not to the contained ethanol.
CONCLUSION
The strong antibacterial effect of REPHA-OS on different stages of oral biofilm development strengthens its application as an alternative adjuvant in oral care therapies.
Topics: Actinomyces; Anti-Bacterial Agents; Biofilms; Veillonella
PubMed: 33794846
DOI: 10.1186/s12903-021-01504-4 -
Molecular Oral Microbiology Apr 2016The development of dental caries and periodontal diseases result from distinct shifts in the microbiota of the tooth-associated biofilm. This in vitro study aimed to...
The development of dental caries and periodontal diseases result from distinct shifts in the microbiota of the tooth-associated biofilm. This in vitro study aimed to investigate changes in biofilm composition and structure, during the shift from a 'supragingival' aerobic profile to a 'subgingival' anaerobic profile. Biofilms consisting of Actinomyces oris, Candida albicans, Fusobacterium nucleatum, Streptococcus oralis, Streptococcus mutans and Veillonella dispar were aerobically grown in saliva-containing medium on hydroxyapatite disks. After 64 h, Campylobacter rectus, Prevotella intermedia and Streptococcus anginosus were further added along with human serum, while culture conditions were shifted to microaerophilic. After 96 h, Porphyromonas gingivalis, Tannerella forsythia and Treponema denticola were finally added and the biofilm was grown anaerobically for another 64 h. At the end of each phase, biofilms were harvested for species-specific quantification and localization. Apart from C. albicans, all other species gradually increased during aerobic and microaerophilic conditions, but remained steady during anaerobic conditions. Biofilm thickness was doubled during the microaerophilic phase, but remained steady throughout the anaerobic phase. Extracellular polysaccharide presence was gradually reduced throughout the growth period. Biofilm viability was reduced during the microaerophilic conversion, but was recovered during the anaerobic phase. This in vitro study has characterized the dynamic structural shifts occurring in an oral biofilm model during the switch from aerobic to anaerobic conditions, potentially modeling the conversion of supragingival to subgingival biofilms. Within the limitations of this experimental model, the findings may provide novel insights into the ecology of oral biofilms.
Topics: Bacteria, Aerobic; Bacteria, Anaerobic; Biofilms; Gingiva; Gingival Diseases; Humans; In Vitro Techniques; Microbial Consortia
PubMed: 26033167
DOI: 10.1111/omi.12108 -
Cell Host & Microbe Aug 2020Gut microbiota play a critical role in infant health. It is now accepted that breastmilk contains live bacteria from endogenous and exogenous sources, but it remains...
Gut microbiota play a critical role in infant health. It is now accepted that breastmilk contains live bacteria from endogenous and exogenous sources, but it remains unclear whether these bacteria transfer to the infant gut and whether this process is influenced by breastmilk feeding practices. Here, we show that certain bacteria, including Streptococcus spp. and Veillonella dispar, co-occur in mothers' milk and their infants' stool, and co-occurrence is reduced when infants receive pumped breastmilk. The relative abundances of commonly shared species are positively correlated between breastmilk and stool. Overall, gut microbiota composition is strongly associated with breastfeeding exclusivity and duration but not breastmilk feeding mode (nursing versus pumping). Moreover, breastmilk bacteria contributed to overall gut microbiota variation to a similar extent as other modifiers of the infant microbiome, such as birth mode. These results provide evidence that breastmilk may transfer bacteria to the infant gut and influence microbiota development.
Topics: Breast Feeding; Breast Milk Expression; Cohort Studies; Feces; Feeding Behavior; Female; Gastrointestinal Microbiome; Humans; Infant; Milk, Human; RNA, Ribosomal, 16S; Streptococcus; Veillonella
PubMed: 32652062
DOI: 10.1016/j.chom.2020.06.009 -
Journal of Gastrointestinal Surgery :... Aug 2020Recently, the link between obesity and gut microbiota has become a focus for research. This study shed some light on the modification of postoperative gut microbial...
BACKGROUND
Recently, the link between obesity and gut microbiota has become a focus for research. This study shed some light on the modification of postoperative gut microbial composition after bariatric surgery.
METHODS
A prospective longitudinal study on healthy lean subjects and patients who underwent bariatric surgery (Roux-en-Y gastric bypass and laparoscopic sleeve gastrectomy) was carried out. Anthropometric and metabolic data, smoking, food preferences data, and stool samples were collected from lean subjects and from obese patients before and 3 and 6 months after surgery (T0, T3, and T6, respectively).
RESULTS
We collected stool samples from 25 obese patients before surgery and 3 and 6 months thereafter and from 25 normal weight patients. After Roux-en-Y gastric bypass, Yokenella regensburgei (p < 0.05), Fusobacterium varium (p < 0.05), Veillonella dispar/atypica (p < 0.05), and Streptococcus australis/gordonii (p < 0.05) were transiently identified in the gut at T3. Roux-en-Y gastric bypass patients had a permanent increase in Akkermansia muciniphila (p < 0.05), which is associated with healthy metabolism, both at T3 and T6. There were no significant changes in gut microbiota in laparoscopic sleeve gastrectomy patients.
CONCLUSIONS
In our study, Roux-en-Y gastric bypass induced major microbial differences and greater weight loss compared with laparoscopic sleeve gastrectomy. Analyzing the microbiota composition, a proliferation of potential pathogens and the onset of beneficial bacteria was observed. The effects of these bacteria on human health are still far from clear. Understanding the mechanisms of action of these bacteria could be the keystone in developing new therapeutic strategies for obesity.
Topics: Bariatric Surgery; Enterobacteriaceae; Fusobacterium; Gastrectomy; Gastric Bypass; Gastrointestinal Microbiome; Humans; Laparoscopy; Longitudinal Studies; Obesity, Morbid; Prospective Studies; Streptococcus; Veillonella
PubMed: 31388884
DOI: 10.1007/s11605-019-04321-x -
Antimicrobial Agents and Chemotherapy Aug 2006Twelve out of 96 Veillonella spp. isolated from oral samples harbored tetracycline resistance genes. The most common resistance gene was tet(M). A tet(M)-positive...
Twelve out of 96 Veillonella spp. isolated from oral samples harbored tetracycline resistance genes. The most common resistance gene was tet(M). A tet(M)-positive Veillonella dispar strain was shown to transfer a Tn916-like element to four Streptococcus spp. by conjugation at a frequency of 5.2 x 10(-6) to 4.5 x 10(-5) per recipient.
Topics: Bacterial Proteins; Conjugation, Genetic; DNA Transposable Elements; DNA, Bacterial; Drug Resistance, Bacterial; Gene Transfer, Horizontal; Genes, Bacterial; Humans; Microbial Sensitivity Tests; Mouth; Streptococcus; Tetracycline Resistance; Veillonella
PubMed: 16870789
DOI: 10.1128/AAC.00217-06 -
Scientific Reports Jan 2021Smoking is a risk factor for periodontal disease, and a cause of oral microbiome dysbiosis. While this has been evaluated for traditional cigarette smoking, there is...
Smoking is a risk factor for periodontal disease, and a cause of oral microbiome dysbiosis. While this has been evaluated for traditional cigarette smoking, there is limited research on the effect of other tobacco types on the oral microbiome. This study investigates subgingival microbiome composition in smokers of different tobacco types and their effect on periodontal health. Subgingival plaques were collected from 40 individuals, including smokers of either cigarettes, medwakh, or shisha, and non-smokers seeking dental treatment at the University Dental Hospital in Sharjah, United Arab Emirates. The entire (~ 1500 bp) 16S rRNA bacterial gene was fully amplified and sequenced using Oxford Nanopore technology. Subjects were compared for the relative abundance and diversity of subgingival microbiota, considering smoking and periodontal condition. The relative abundances of several pathogens were significantly higher among smokers, such as Prevotella denticola and Treponema sp. OMZ 838 in medwakh smokers, Streptococcus mutans and Veillonella dispar in cigarette smokers, Streptococcus sanguinis and Tannerella forsythia in shisha smokers. Subgingival microbiome of smokers was altered even in subjects with no or mild periodontitis, probably making them more prone to severe periodontal diseases. Microbiome profiling can be a useful tool for periodontal risk assessment. Further studies are recommended to investigate the impact of tobacco cessation on periodontal disease progression and oral microbiome.
Topics: Adolescent; Adult; Bacteria; Cigarette Smoking; Dental Plaque; Female; Gingiva; Humans; Male; Microbiota; Middle Aged; Periodontitis; Periodontium; Pilot Projects; RNA, Ribosomal, 16S; Tobacco Smoking; United Arab Emirates; Young Adult
PubMed: 33441919
DOI: 10.1038/s41598-020-80937-3 -
BMC Oral Health Nov 2019The extent to which the composition and diversity of the oral microbiome varies with age is not clearly understood.
BACKGROUND
The extent to which the composition and diversity of the oral microbiome varies with age is not clearly understood.
METHODS
The 16S rRNA gene of subgingival plaque in 1219 women, aged 53-81 years, was sequenced and its taxonomy annotated against the Human Oral Microbiome Database (v.14.5). Composition of the subgingival microbiome was described in terms of centered log(2)-ratio (CLR) transformed OTU values, relative abundance, and prevalence. Correlations between microbiota abundance and age were evelauted using Pearson Product Moment correlations. P-values were corrected for multiple testing using the Bonferroni method.
RESULTS
Of the 267 species identified overall, Veillonella dispar was the most abundant bacteria when described by CLR OTU (mean 8.3) or relative abundance (mean 8.9%); whereas Streptococcus oralis, Veillonella dispar and Veillonella parvula were most prevalent (100%, all) when described as being present at any amount. Linear correlations between age and several CLR OTUs (Pearson r = - 0.18 to 0.18), of which 82 (31%) achieved statistical significance (P < 0.05). The correlations lost significance following Bonferroni correction. Twelve species that differed across age groups (each corrected P < 0.05); 5 (42%) were higher in women ages 50-59 compared to ≥70 (corrected P < 0.05), and 7 (48%) were higher in women 70 years and older.
CONCLUSIONS
We identified associations between several bacterial species and age across the age range of postmenopausal women studied. Understanding the functions of these bacteria could identify intervention targets to enhance oral health in later life.
Topics: Aged; Aged, 80 and over; Bacteria; Dental Plaque; Female; Humans; Microbiota; Middle Aged; Postmenopause; RNA, Ribosomal, 16S
PubMed: 31722703
DOI: 10.1186/s12903-019-0906-2 -
Atherosclerosis May 2019Although most risk factors for cardiac valve calcification (VC) are similar to those for coronary artery disease (CAD), they differ regarding lesions and clinical... (Comparative Study)
Comparative Study
BACKGROUND AND AIMS
Although most risk factors for cardiac valve calcification (VC) are similar to those for coronary artery disease (CAD), they differ regarding lesions and clinical symptoms. Recently, increasing evidence suggests that intestinal bacteria play essential roles in cardiovascular disease (CVD). It is plausible that the gut microbiota is linked to the occurrence of different CVDs under similar risk factors. Thus, we aimed to explore the gut microbiomes in patients with VC or CAD and determine their underlying connections.
METHODS
We collected samples from 119 subjects and performed 16S rRNA gene sequencing to analyze the gut microbiomes in VC and CAD patients and in control volunteers.
RESULTS
The gut microbiomes of VC and CAD patients were significantly different in terms of beta-diversity. Bacteria from Veillonella dispar, Bacteroides plebeius and Fusobacterium were enriched in the VC group, while members of Collinsella aerofaciens, Megamonas, Enterococcus, Megasphaera, Dorea and Blautia were decreased. According to the association with dyslipidemia, seven operational taxonomic units (OTUs), including Parabacteroides distasonis, Megamonas, Fusobacterium, Bacteroides sp., Bacteroides plebeius, Lactobacillus and Prevotella copri, were regarded as potential pathogens for CVDs. Additionally, Prevotella copri might be a keystone of CVDs, especially in VC patients, while Collinsella aerofaciens is a possible keystone of CAD, based on the multi-correlations of these bacteria with other OTUs in microbial communities.
CONCLUSIONS
Patients with VC and CAD suffer from different gut microbial dysbiosis. The gut microbiomes are associated with the clinical characteristics in these diseases and might be potential therapeutic targets.
Topics: Adult; Aged; Calcinosis; Coronary Artery Disease; Dysbiosis; Female; Gastrointestinal Microbiome; Heart Valve Diseases; Humans; Male; Middle Aged
PubMed: 30897381
DOI: 10.1016/j.atherosclerosis.2018.11.038