Under the lens: using Raman spectroscopy as a unique system in biofilm analyses.

Biofilms are microbial communities that adhere to surfaces and each other, encapsulated in a protective extracellular matrix. These structures enhance resistance to antimicrobials, contributing to 65-80% of human infections. The transition from free-living cells to structured biofilms involves a myriad of molecular and structural adaptations.

Investigating the Prevalence of Fungi in Diabetic Ulcers: An Under-Recognised Contributor to Polymicrobial Biofilms.

Diabetic foot ulcers (DFUs) are common complications for diabetic patients, often exacerbated by complex polymicrobial biofilm infections. While the majority of DFU studies are bacterial focused, fungi have also been identified. This study aims to investigate the prevalence of fungi in DFUs, as well as their potential role and influence on persistence and wound healing.

Organotypic Tissue Model Systems for Investigating Host-Pathogen Interactions In Vitro.

Recapitulating the host-pathogen interface at the epithelial or mucosal barrier in vitro remains a challenging prospect for infection biologists. While in-house grown 2D epithelial monolayers lack true representation of the in vivo situation, commercially available tissue models are often overlooked due to their cost and practicality. However, with careful planning, such models provide reproducible platforms for a vast array of different applications.

Predicting the invasiveness of alpine newts in the UK.

Unlabelled: Predicting invasion risk to novel environments is essential for risk management and conservation decision making but the evolutionary lineage at which to make these predictions is often unclear. Here we predict the current suitability across the United Kingdom (UK) for the alpine newt , a species with a complex evolutionary history, a broad native range, a growing number of introduced populations and anecdotal reports of ecological consequences to native amphibian communities. We use species distribution and ecological niche modelling to predict environmental suitability of the alpine newt in the UK at both the species-level and lineage-level and to quantify evolutionary lineage niche overlap.

Multiple Routes to Color Convergence in a Radiation of Neotropical Poison Frogs.

Convergent evolution is defined as the independent evolution of similar phenotypes in different lineages. Its existence underscores the importance of external selection pressures in evolutionary history, revealing how functionally similar adaptations can evolve in response to persistent ecological challenges through a diversity of evolutionary routes. However, many examples of convergence, particularly among closely related species, involve parallel changes in the same genes or developmental pathways, raising the possibility that homology at deeper mechanistic levels is an important facilitator of phenotypic convergence.

Investigating the role of Candida albicans as a universal substrate for oral bacteria using a transcriptomic approach: implications for interkingdom biofilm control?

Candida albicans is frequently identified as a colonizer of the oral cavity in health and has recently been termed a "keystone" commensal due to its role on the bacterial communities. However, the role that C. albicans plays in such interactions is not fully understood.

strains exhibit heterogenous tolerance to direct cold atmospheric plasma therapy.

The global clinical and socioeconomic impact of chronic wounds is substantial. The main difficulty that clinicians face during the treatment of chronic wounds is the risk of infection at the wound site. Infected wounds arise from an accumulation of microbial aggregates in the wound bed, leading to the formation of polymicrobial biofilms that can be largely resistant to antibiotic therapy.

bacterial vaginosis biofilm community manipulation using endolysin therapy.

Bacterial vaginosis (BV) affects approximately 26% of women of childbearing age globally, presenting with 3-5 times increased risk of miscarriage and two-fold risk of pre-term birth Antibiotics (metronidazole and clindamycin) are typically employed to treat BV; however the success rate is low due to the formation of recalcitrant polymicrobial biofilms. As a novel therapeutic, promising results have been obtained using endolysins, although to date their efficacy has only been demonstrated against simple biofilm models. In this study, a four-species biofilm was developed consisting of and .

Generation of Multispecies Oral Bacteria Biofilm Models.

It is well-recognized that oral biofilms that occur in health and disease have a polymicrobial composition, though these are poorly reflected in the literature, with many studies focussing on simple mono-species biofilm model systems. The utility of polymicrobial biofilm model systems is that they more accurately reflect the oral cavity and allow researchers to ask relevant questions in basic science studies, pharmaceutical screening, and investigating inflammatory interactions. Here we describe the detailed methodology of how to sequentially construct and maintain polymicrobial biofilm models pertinent to caries, periodontal disease, and denture stomatitis.

Investigating Dual-Species and Staphylococcal Biofilm Antiseptic Challenge.

can persistently colonize human skin, alongside a diverse bacterial microbiome. In this study we aimed to investigate the efficacy of antiseptic activities on dual-species interkingdom biofilms containing staphylococci to determine if antiseptic tolerance was negatively impacted by dual-species biofilms. Chlorhexidine, povidone iodine, and hydrogen peroxide (HO), were able to significantly reduce biofilm viable cell counts following exposure at 2%, 10%, and 3%, respectively.

Screening the Tocriscreen™ bioactive compound library in search for inhibitors of Candida biofilm formation.

Biofilms formed by Candida species present a significant clinical problem due to the ineffectiveness of many conventional antifungal agents, in particular the azole class. We urgently require new and clinically approved antifungal agents quickly for treatment of critically ill patients. To improve efficiency in antifungal drug development, we utilized a library of 1280 biologically active molecules within the Tocriscreen 2.

Cell Viability Assays for Candida auris.

Cell viability assays are useful for assessing the efficacy of antifungal therapeutics and disinfection strategies in vitro. In recent years these assays have been fundamental for the testing of conventional and novel therapies against the nosocomial fungal pathogen Candida auris. Here we provide detailed descriptions of methods for assessing cellular viability of Candida auris in vitro, such as metabolic assays (XTT and resazurin), colony-forming unit counting, live/dead quantitative PCR, and fluorescent staining for microscopic analyses.

Assessing the inflammatory response to in vitro polymicrobial wound biofilms in a skin epidermis model.

Wounds can commonly become infected with polymicrobial biofilms containing bacterial and fungal microorganisms. Microbial colonization of the wound can interfere with sufficient healing and repair, leading to high rates of chronicity in certain individuals, which can have a huge socioeconomic burden worldwide. One route for alleviating biofilm formation in chronic wounds is sufficient treatment of the infected area with topical wound washes and ointments.

An In Vitro Evaluation of Denture Cleansing Regimens against a Polymicrobial Denture Biofilm Model.

Denture stomatitis (DS) is an inflammatory disease resulting from a polymicrobial biofilm perturbation at the denture surface-palatal mucosa interface. Recommendations made by dental health care professionals often lack clarity for appropriate denture cleaning. This study investigated the efficacy of brushing with off-the-shelf denture cleanser (DC) tablets (Poligrip) vs.

Phylogenomic analysis of evolutionary relationships in Ranitomeya poison frogs (Family Dendrobatidae) using ultraconserved elements.

The use of genome-scale data in phylogenetics has enabled recent strides in determining the relationships between taxa that are taxonomically problematic because of extensive morphological variation. Here, we employ a phylogenomic approach to infer evolutionary relationships within Ranitomeya (Anura: Dendrobatidae), an Amazonian lineage of poison frogs consisting of 16 species with remarkable diversity in color pattern, range size, and parental care behavior. We infer phylogenies with all described species of Ranitomeya from ultraconserved nuclear genomic elements (UCEs) and also estimate divergence times.

Investigating the Transcriptome of in a Dual-Species Biofilm Model.

is an opportunistic pathogen found throughout multiple body sites and is frequently co-isolated from infections of the respiratory tract and oral cavity with Herein we present the first report of the effects that elicits on the transcriptome. Dual-species biofilms containing and mutants defective in or were optimised and characterised, followed by transcriptional profiling of by RNA-sequencing (RNA-seq). Altered phenotypes in mutants revealed specific interaction profiles between fungus and bacteria.

Chitosan Enhances the Anti-Biofilm Activity of Biodentine against an Interkingdom Biofilm Model.

Endodontic infection is a biofilm disease that is difficult to irradicate with current treatment protocols, and as such, persistent micro-organisms may lead to ongoing or recurrent disease. The potential for the use of enhanced filling materials to modify biofilm regrowth is a promising strategy. This current study aimed to evaluate the anti-biofilm efficacy of calcium silicate cements modified with chitosan.

Glycation of Host Proteins Increases Pathogenic Potential of .

The non-enzymatic addition of glucose (glycation) to circulatory and tissue proteins is a ubiquitous pathophysiological consequence of hyperglycemia in diabetes. Given the high incidence of periodontitis and diabetes and the emerging link between these conditions, it is of crucial importance to define the basic virulence mechanisms employed by periodontopathogens such as in mediating the disease process. The aim of this study was to determine whether glycated proteins are more easily utilized by to stimulate growth and promote the pathogenic potential of this bacterium.

Antifungal-Loaded Calcium Sulfate Beads as a Potential Therapeutic in Combating Candida auris.

Candida auris provides a substantial global nosocomial threat clinically. With the recent emergence that the organism can readily colonize skin niches, it will likely continue to pose a risk in health care units, particularly to patients undergoing surgery. The purpose of this study was to investigate the efficacy of antifungal-loaded calcium sulfate (CS) beads in combatting C.

Assessing the Bioactive Profile of Antifungal-Loaded Calcium Sulfate against Fungal Biofilms.

Calcium sulfate (CS) has been used clinically as a bone- or void-filling biomaterial, and its resorptive properties have provided the prospect for its use as a release mechanism for local antibiotics to control biofilms. Here, we aimed to test CS beads loaded with three antifungal drugs against planktonic and sessile fungal species to assess whether these antifungal beads could be harnessed to provide consistent release of antifungals at biofilm-inhibitory doses. A panel of different fungal species ( = 15) were selected for planktonic broth microdilution testing with fluconazole (FLZ), amphotericin B (AMB), and caspofungin (CSP).

A New Method for Integrating Ecological Niche Modeling with Phylogenetics to Estimate Ancestral Distributions.

Ancestral range estimation and projection of niche models into the past have both become common in evolutionary studies where the ancient distributions of organisms are in question. However, these methods are hampered by complementary hurdles: discrete characterization of areas in ancestral range estimation can be overly coarse, especially at shallow timescales, and niche model projection neglects evolution. Phylogenetic niche modeling accounts for both of these issues by incorporating knowledge of evolutionary relationships into a characterization of environmental tolerances.

as an Essential "Keystone" Component within Polymicrobial Oral Biofilm Models?

: Existing standardized biofilm assays focus on simple mono-species or bacterial-only models. Incorporating into complex biofilm models can offer a more appropriate and relevant polymicrobial biofilm for the development of oral health products. : This study aimed to assess the importance of interkingdom interactions in polymicrobial oral biofilm systems with or without , and test how these models respond to oral therapeutic challenges in vitro.

Filling the Void: An Optimized Polymicrobial Interkingdom Biofilm Model for Assessing Novel Antimicrobial Agents in Endodontic Infection.

There is a growing realization that endodontic infections are often polymicrobial, and may contain spp. Despite this understanding, the development of new endodontic irrigants and models of pathogenesis remains limited to mono-species biofilm models and is bacterially focused. The purpose of this study was to develop and optimize an interkingdom biofilm model of endodontic infection and use this to test suitable anti-biofilm actives.