Corynebacterial membrane vesicles disrupt cariogenic interkingdom assemblages.

Polymicrobial diseases such as periodontal disease and caries pose significant treatment challenges due to their resistance to common approaches like antibiotic therapy. These infections exhibit increased resilience, due to microbial interactions that also disrupt host immune responses. Current research focuses on virulence and disease-promoting interactions, but less is known about interactions that could inhibit or prevent disease development.

Characterization of the Epileptogenic Phenotype and Response to Antiseizure Medications in Lissencephaly Patients.

Background: Patients with lissencephaly typically present with severe psychomotor retardation and drug-resistant seizures. The aim of this study was to characterize the epileptic phenotype in a genotypically and radiologically well-defined patient cohort and to evaluate the response to antiseizure medication (ASM). Therefore, we retrospectively evaluated 47 patients of five genetic forms (, , , , ) using family questionnaires, standardized neuropediatric assessments, and patients' medical reports.

An inflammatory paradox: strategies inflammophilic oral pathobionts employ to exploit innate immunity via neutrophil manipulation.

Inflammatory dysbiotic diseases present an intriguing biological paradox. Like most other infectious disease processes, the alarm bells of the host are potently activated by tissue-destructive pathobionts, triggering a cascade of physiological responses that ultimately mobilize immune cells like neutrophils to sites of active infection. Typically, these inflammatory host responses are critical to inhibit and/or eradicate infecting microbes.

Ribosomal-processing cysteine protease homolog modulates glucan production and interkingdom interactions.

Unlabelled: Glucan-dependent biofilm formation is a crucial process in the establishment of as a cariogenic oral microbe. The process of glucan formation has been investigated in great detail, with glycosyltransferases GtfB, GtfC, and GtfD shown to be indispensable for the synthesis of glucans from sucrose. Glucan production can be visualized during biofilm formation through fluorescent labeling, and its abundance, as well as the effect of glucans on general biofilm architecture, is a common phenotype to study virulence regulation.

Complete genome sequence of strain JM503A, a genetically tractable dental abscess clinical isolate.

is a pathobiont of humans that is often found in abundance at sites of mucosal inflammation as well as within malignant tumors. Here, we report the complete genome sequence of strain JM503A, which is a genetically tractable clinical isolate derived from a human odontogenic abscess specimen.

Stratification of Fusobacterium nucleatum by local health status in the oral cavity defines its subspecies disease association.

The ubiquitous inflammophilic oral pathobiont Fusobacterium nucleatum (Fn) is widely recognized for its strong association with inflammatory dysbiotic diseases and cancer. Fn is subdivided into four subspecies, which are historically considered functionally interchangeable in the oral cavity. To test this assumption, we analyzed patient-matched dental plaque and odontogenic abscess clinical specimens and examined whether an inflammatory environment selects for/against particular Fn subspecies.

Autoantibody status, neuroradiological and clinical findings in children with acute cerebellitis.

Background: Acute cerebellitis (AC) in children and adolescents is an inflammatory disease of the cerebellum due to viral or bacterial infections but also autoimmune-mediated processes.

Objective: To investigate the frequency of autoantibodies in serum and CSF as well as the neuroradiological features in children with AC.

Material And Methods: Children presenting with symptoms suggestive of AC defined as acute/subacute onset of cerebellar symptoms and MRI evidence of cerebellar inflammation or additional CSF pleocytosis, positive oligoclonal bands (OCBs), and/or presence of autoantibodies in case of negative cerebellar MRI.

Mass spectrometry and split luciferase complementation assays reveal the MecA protein interactome of .

MecA is a highly conserved adaptor protein encoded by prokaryotes from the phylum. MecA mutants exhibit similar pleiotropic defects in a variety of organisms, although most of these phenotypes currently lack a mechanistic basis. MecA mediates ClpCP-dependent proteolysis of its substrates, but only several such substrates have been reported in the literature and there are suggestions that proteolysis-independent regulatory mechanisms may also exist.

Quantifying picomoles of analyte from less than 100 live bacteria: A novel method with a buffering hydrogel as an electrochemical cell.

Microenvironmental changes in the chemical surrounding of bacterial cells might have a profound impact on the ecology of biofilms. However, quantifying total amount of picomoles of analyte from a miniscule number of bacteria is an analytical challenge. Here we provide a novel microliter volume hydrogel based electrochemical cell platform suitable of coulometrically measuring hydrogen peroxide (HO) produced by less than 100 cells of , a relevant member of the healthy oral microbiome.

The prevalence of subspecies in the oral cavity stratifies by local health status.

The ubiquitous inflammophilic pathobiont is widely recognized for its strong association with a variety of human dysbiotic diseases such as periodontitis and oral/extraoral abscesses, as well as multiple types of cancer is currently subdivided into four subspecies: subspecies () ( (), and (). Although these subspecies have been historically considered as functionally interchangeable in the oral cavity, direct clinical evidence is largely lacking for this assertion. Consequently, we assembled a collection of oral clinical specimens to determine whether subspecies prevalence in the oral cavity stratifies by local oral health status.

Employing Cloning-Independent Mutagenesis of Parvimonas micra for the Study of Cell Wall Biogenesis.

The cell wall plays an important structural role for bacteria and is intimately tied to a variety of critical processes ranging from growth and differentiation to pathogenesis. Our understanding of cell wall biogenesis is primarily derived from a relatively small number of heavily studied model organisms. Consequently, these processes can only be inferred for the vast majority of prokaryotes, especially among groups of uncharacterized and/or genetically intractable organisms.

Molecular commensalism-how to investigate underappreciated health-associated polymicrobial communities.

The study of human commensal bacteria began with the first observation of prokaryotes >340 years ago. Since then, the study of human-associated microbes has been justifiably biased toward the study of infectious pathogens. However, the role of commensal microbes has in recent years begun to be understood with some appreciation of them as potential protectors of host health rather than bystanders.

Environmental influences on Streptococcus sanguinis membrane vesicle biogenesis.

Membrane vesicles are produced by Gram-negative and Gram-positive bacteria. While membrane vesicles are potent elicitors of eukaryotic cells and involved in cell-cell communication, information is scarce about their general biology in the context of community members and the environment. Streptococcus sanguinis, a Gram-positive oral commensal, is prevalent in the oral cavity and well-characterized for its ability to antagonize oral pathobionts.

Aspects of oral streptococcal metabolic diversity: Imagining the landscape beneath the fog.

It is widely acknowledged that the human-associated microbial community influences host physiology, systemic health, disease progression, and even behavior. There is currently an increased interest in the oral microbiome, which occupies the entryway to much of what the human initially encounters from the environment. In addition to the dental pathology that results from a dysbiotic microbiome, microbial activity within the oral cavity exerts significant systemic effects.

Glycerol metabolism supports oral commensal interactions.

During oral biofilm development, interspecies interactions drive species distribution and biofilm architecture. To understand what molecular mechanisms determine these interactions, we used information gained from recent biogeographical investigations demonstrating an association of corynebacteria with streptococci. We previously reported that Streptococcus sanguinis and Corynebacterium durum have a close relationship through the production of membrane vesicle and fatty acids leading to S.

Adaptation of Prokaryotic Toxins for Negative Selection and Cloning-Independent Markerless Mutagenesis in Streptococcus Species.

The Streptococcus mutans genetic system offers a variety of strategies to rapidly engineer targeted chromosomal mutations. Previously, we reported the first S. mutans negative selection system that functions in a wild-type background.

Simultaneous Chemical Mapping of Live Biofilm Microenvironmental pH and Hydrogen Peroxide in Real Time with a Triple Scanning Electrochemical Microscopy Tip.

Dental plaque biofilm is a complex ecosystem. The distribution of microbial species in the biofilm is heavily influenced by local chemical interactions that result from diverse metabolic activities and the nature of the released molecules. As a relevant example, HO-producing bacteria can antagonize disease-associated bacteria, leading to the maintenance of a healthy oral microbiome.

Who is in the driver's seat? Parvimonas micra: An understudied pathobiont at the crossroads of dysbiotic disease and cancer.

Recent advances in our understanding of microbiome composition at sites of inflammatory dysbiosis have triggered a substantial interest in a variety of historically understudied bacteria, especially among fastidious obligate anaerobes. A plethora of new evidence suggests that these microbes play outsized roles in establishing synergistic polymicrobial infections at many different sites in the human body. Parvimonas micra is a prime example of such an organism.

Illuminating the oral microbiome and its host interactions: tools and approaches for molecular ecological studies.

A more comprehensive understanding of oral diseases like caries and periodontitis is dependent on an intimate understanding of the microbial ecological processes that are responsible for disease development. With this review, we provide a comprehensive overview of relevant molecular ecology techniques that have played critical roles in the current understanding of human oral biofilm development, interspecies interactions, and microbiome biogeography. The primary focus is on relevant technologies and examples available in the oral microbiology literature.

Illuminating the oral microbiome and its host interactions: tools and approaches for molecular microbiology studies.

Advancements in DNA sequencing technologies within the last decade have stimulated an unprecedented interest in the human microbiome, largely due the broad diversity of human diseases found to correlate with microbiome dysbiosis. As a direct consequence of these studies, a vast number of understudied and uncharacterized microbes have been identified as potential drivers of mucosal health and disease. The looming challenge in the field is to transition these observations into defined molecular mechanistic studies of symbiosis and dysbiosis.

Methods to Study Antagonistic Activities Among Oral Bacteria.

Most bacteria in nature exist in multispecies communities known as biofilms. In the natural habitat where resources (nutrient, space, etc.) are usually limited, individual species must compete or collaborate with other neighboring species in order to perpetuate in the multispecies community.