Exploring the Genetic and Functional Diversity of Survival Factor RagAB.

is a key pathogen in periodontitis. Its outer membrane contains the RagAB transport complex, which has been implicated in protein uptake, essential for a proteolytic species. RagA is a 22-stranded β-barrel, and RagB is the corresponding 4-TPR lid, together forming a TonB-dependent system acting as a "pedal bin".

Insights into Within-Host Evolution and Dynamics of Oral and Intestinal Streptococci Unveil Niche Adaptation.

The oral-gut axis is a complex system linking the oral cavity and gastrointestinal tract, impacting host health and microbial composition. This study investigates genetic changes and adaptive mechanisms employed by streptococci-one of the few genera capable of colonizing oral and intestinal niches-within the same individual. We conducted whole-genome sequencing (WGS) on 218 streptococcal isolates from saliva and fecal samples of 14 inflammatory bowel disease (IBD) patients and 12 healthy controls.

Isolation, identification, and significance of salivary spp., spp., and in patients with inflammatory bowel disease.

The global prevalence of inflammatory bowel disease (IBD) is on the rise, prompting significant attention from researchers worldwide. IBD entails chronic inflammatory disorders of the intestinal tract, characterized by alternating flares and remissions. Through high-throughput sequencing, numerous studies have unveiled a potential microbial signature for IBD patients showing intestinal enrichment of oral-associated bacteria.

Exploring the genetic and functional diversity of Porphyromonas gingivalis long fimbriae.

Porphyromonas gingivalis is a key pathobiont in periodontitis. Its long fimbriae consist of a single anchor (FimB), a varying number of stalk (FimA), and three accessory (tip-related) proteins (FimC, FimD, and FimE). Based on 133 strains/genomes available, it was our aim to investigate the diversity within FimA and FimB and explain the variety of long fimbriae (super-)structures.

Evaluation of hydrocortisone as a strain-dependent growth-regulator of Porphyromonasgingivalis.

Objective: Porphyromonas gingivalis is an oral key pathogen and known to be very diverse in geno- and phenotypes. It is a fastidious bacterium with low O-tolerance and 3-7 days of incubation are necessary. With growing interest in the field of microbial endocrinology we explored the potential growth-stimulating effect of hydrocortisone (HC, synonym cortisol) on P.

The oral-gut axis: Salivary and fecal microbiome dysbiosis in patients with inflammatory bowel disease.

Inflammatory bowel disease (IBD) is a group of chronic inflammatory disorders that fall into two main categories: Crohn's disease (CD) and ulcerative colitis (UC). The gastrointestinal tract extends from the mouth to the anus and harbors diverse bacterial communities. Several sequencing-based studies have identified an intestinal enrichment of oral-associated bacteria and demonstrated their ability to induce intestinal inflammation in mice, suggesting that intestinal pathobionts originate from the oral cavity, particularly members of the genus .

Antimicrobial efficiency and cytocompatibility of different decontamination methods on titanium and zirconium surfaces.

Objectives: The purpose of this study was to investigate the efficiency of different implant-decontamination methods regarding biofilm modification and potential cytotoxic effects. Therefore, the amount of biofilm reduction, cytocompatibility, and elementary surface alterations were evaluated after decontamination of titanium and zirconium surfaces.

Material And Methods: Titanium and zirconium disks were contaminated with a newly developed high-adherence biofilm consisting of six microbial species.

Impact of sucroferric oxyhydroxide on the oral and intestinal microbiome in hemodialysis patients.

Hyperphosphatemia is a consequence of chronic kidney disease associated with mineral/bone impairment, increased cardiovascular events and mortality. Therapeutically, most dialysis patients have to take phosphate binders. Here, we investigated effects of the Fe(3+)-based phosphate binder sucroferric oxyhydroxide (SFOH) on the oral and gastrointestinal microbiome of 11 hemodialysis patients.

Impact of Three Nonsurgical, Full-Mouth Periodontal Treatments on Total Bacterial Load and Selected Pathobionts.

For the treatment of periodontitis stage III/IV, a quadrant/week-wise debridement (Q-SRP) was compared with three full-mouth approaches: full-mouth scaling (FMS, accelerated Q-SRP within 24 h), full-mouth scaling with chlorhexidine-based disinfection (FMD), and FMD with adjuvant erythritol air polishing (FMDAP). The objective of this prospective, randomized study (a substudy of ClinicalTrials.gov, identifier: NCT03509233) was to compare the clinical and microbiological effects of the treatments.

Isoeugenol-functionalized nanogels inhibit peri-implantitis associated bacteria in vitro.

Objectives: Obligate and facultative anaerobic bacteria adhering to dental implants are a major cause for peri-implant inflammation, which, if left untreated, can lead to implant loss. Previously, our group developed a new route for the synthesis of isoeugenol-functionalized aqueous nanogels for implant coatings.

Methods: Here, the antimicrobial activity of several new nanogels differing in spacer length (n = 6, 9, 44), radius (60-200 nm), and amount of isoeugenol functional substance (1-20 mol%) was tested against the following peri-implantitis-associated species: Fusobacterium nucleatum, Porphyromonas gingivalis, Prevotella intermedia, Aggregatibacter actinomycetemcomitans, Escherichia coli, Actinomyces viscosus, Enterococcus faecalis, Staphylococcus aureus, Streptococcus oralis, S.

The Effect of Toothpastes Containing Natural Extracts on Bacterial Species of a Microcosm Biofilm and on Enamel Caries Development.

This study investigated the effects of herbal toothpaste on bacterial counts and enamel demineralization. Thirty-six bovine enamel samples were exposed to a microcosm biofilm using human saliva and McBain saliva (0.2% sucrose) for 5 days at 37 °C and first incubated anaerobically, then aerobically-capnophilically.

The Antimicrobial Susceptibility of : Genetic Repertoire, Global Phenotype, and Review of the Literature.

The in vitro antimicrobial susceptibility of 29 strains of the major periodontal pathogen and three (as an ancestor) to nine antibiotics (amoxicillin, amoxicillin/clavulanate, clindamycin, metronidazole, moxifloxacin, doxycycline, azithromycin, imipenem, and cefoxitin) was evaluated by E-testing of minimal inhibitory concentration (MIC) according to international standards. The results were compared with 16 international studies reporting MICs from 1993 until recently. In addition, 77 currently available genomes were screened for antimicrobial resistance genes.

A New Species-Specific Typing Method for Salivarius Group Streptococci Based on the Dephospho-Coenzyme A Kinase () Gene Sequencing.

Viridans streptococci are a group of α-hemolytic streptococcal species. They are mainly commensals, most abundant in the mouth supporting oral health. But they also include important human pathogens such as .

The Effect of Solutions Containing Extracts of Vochysia tucanorum Mart., Myrcia bellaCambess., Matricaria chamomilla L. and Malva sylvestris L. on Cariogenic Bacterial Species and Enamel Caries Development.

This study evaluated the effect of experimental solutions containing plant extracts on bacterial species and enamel caries prevention. Microcosm biofilm was produced from human saliva mixed with McBain saliva (0.2% sucrose) on bovine enamel for 5 days (3 days under anaerobiosis and 2 days under aerobiosis) at 37°C.

A concerted probiotic activity to inhibit periodontitis-associated bacteria.

Periodontitis can result in tooth loss and the associated chronic inflammation can provoke several severe systemic health risks. Adjunctive to mechanical treatment of periodontitis and as alternatives to antibiotics, the use of probiotic bacteria was suggested. In this study, the inhibitory effect of the probiotic Streptococcus salivarius subsp.

Phylogeographical Analysis Reveals the Historic Origin, Emergence, and Evolutionary Dynamics of Methicillin-Resistant ST228.

Background: Methicillin-resistant (MRSA) is a common healthcare-associated pathogen that remains a major public health concern. Sequence type 228 (ST228) was first described in Germany and spread to become a successful MRSA clone in several European countries. In 2000, ST228 emerged in Lausanne and has subsequently caused several large outbreaks.

Combining Standard Molecular Typing and Whole Genome Sequencing to Investigate Epidemiology in Intensive Care Units.

is one of the main pathogens responsible for nosocomial infections, particularly in Intensive Care Units (ICUs). Due to the complexity of ecology, only powerful typing methods can efficiently allow its surveillance and the detection during expanding outbreaks. An increase in incidence was observed in the ICUs of the Lausanne University Hospital between 2010 and 2014.

Deep sequencing of biofilm microbiomes on dental composite materials.

: The microbiome on dental composites has not been studied in detail before. It has not been conclusively clarified whether restorative materials influence the oral microbiome. : We used Illumina Miseq next-generation sequencing of the 16S V1-V2 region to compare the colonisation patterns of bovine enamel (BE) and the composite materials Grandio Flow (GF) and Grandio Blocs (GB) after 48 h in 14 volunteers.

Phenotypic and Genomic Analyses of Burkholderia stabilis Clinical Contamination, Switzerland.

A recent hospital outbreak related to premoistened gloves used to wash patients exposed the difficulties of defining Burkholderia species in clinical settings. The outbreak strain displayed key B. stabilis phenotypes, including the inability to grow at 42°C; we used whole-genome sequencing to confirm the pathogen was B.

Isolation and Bacteriocin-Related Typing of .

subspecies is explored as an anti-cariogenic probiotic. Here, subjecting freshly stimulated saliva samples of 35 healthy volunteers, six epidemiologically unrelated and two related strains were isolated (prevalence around 20%) applying a newly developed three-step procedure. Furthermore, the probiotic strain 7746 (AB-Dentisanium®) was tested under a variety of environmental conditions for its inhibitory effect on six , two , 15 other oral or intestinal streptococci, 15 strains, and six representatives of other species including periodontopathogens.

Challenges of next-generation sequencing targeting anaerobes.

Next-generation sequencing allows for investigating the composition of microbiomes that are associated with infection (clinical microbiology) or dysbiosis (microbial ecology). The most commonly applied short-read sequencing technologies are Illumina MiSeq/HiSeq and Ion Torrent PGM, however, other platforms that generate long-reads are under way and optimized. A pre-condition for representative results is an appropriate method for contamination-free collection, homogenization, storage of specimens and a subsequent efficient DNA extraction protocol.

Evaluating the use of whole-genome sequencing for outbreak investigations in the lack of closely related reference genome.

Whole-genome sequencing (WGS) has emerged as a powerful molecular typing method for outbreak analysis enabling the rapid discrimination between outbreak and non-outbreak isolates. However, such analysis can be challenging in the absence of closely related reference genomes. In this study, we assessed the use of WGS in investigating an outbreak of a relatively understudied bacterial pathogen with no publicly available closely related reference genome.

Draft Genome Sequences of Two Carbapenemase-Producing Clinical Strains Isolated from Albanian and Togolese Patients.

We report here the draft genome sequences of two multidrug-resistant clinical strains, H31499 and H31506, which were isolated at the Lausanne University Hospital in 2015 from an Albanian and a Togolese patient, respectively.