Genetic interaction analysis of transcription factors and in the regulation of respiration and fluconazole susceptibility.

is the second most common cause of invasive candidiasis and is widely known to have reduced susceptibility to fluconazole relative to many other spp. Upc2A is a transcription factor that regulates ergosterol biosynthesis gene expression under conditions of sterol stress such as azole drug treatment or hypoxia. Through an microevolution experiment, we found that loss-of-function mutants of the ATF/CREB transcription factor suppresses the fluconazole hyper-susceptibility of the ∆ mutant.

pharmacodynamic evaluation of the novel nystatin derivative BSG005 in the invasive candidiasis and invasive pulmonary aspergillosis mouse models.

Nystatin, a polyene, is one of the oldest antifungal drugs with wide potency. BSG005 is a novel, chemically modified, nystatin-like molecule in development for systemic therapy. We evaluated the pharmacokinetic/pharmacodynamic (PK/PD) relationships and target exposures using invasive pulmonary aspergillosis (IPA) and invasive candidiasis (IC) infection models for BSG005 against common fungal pathogens including , , , and .

Analogs of the anti-malaria drug mefloquine have broad-spectrum antifungal activity and are efficacious in a model of disseminated infection.

Only three classes of antifungal drugs are currently in clinical use. Here, we report that derivatives of the malarial drug mefloquine have broad-spectrum antifungal activity including difficult-to-treat molds and endemic fungi. Pharmacokinetic and efficacy studies of NSC-4377 indicate that it penetrates the central nervous system and is active against .

Analogues of the anti-malaria drug mefloquine have broad spectrum antifungal activity and are efficacious in a model of disseminated infection.

Only three classes of antifungal drugs are currently in clinical use. Here, we report that derivatives of the malarial drug mefloquine have broad spectrum antifungal activity including difficult to treat molds and endemic fungi. Pharmacokinetic and efficacy studies of NSC-4377 indicate it penetrates the central nervous system and is active against in vivo.

Biofilm-associated metabolism via ERG251 in Candida albicans.

Biofilm formation by the fungal pathogen Candida albicans is the basis for its ability to infect medical devices. The metabolic gene ERG251 has been identified as a target of biofilm transcriptional regulator Efg1, and here we report that ERG251 is required for biofilm formation but not conventional free-living planktonic growth. An erg251Δ/Δ mutation impairs biofilm formation in vitro and in an in vivo catheter infection model.

Secretion of the fungal toxin candidalysin is dependent on conserved precursor peptide sequences.

The opportunistic fungal pathogen Candida albicans damages host cells via its peptide toxin, candidalysin. Before secretion, candidalysin is embedded in a precursor protein, Ece1, which consists of a signal peptide, the precursor of candidalysin and seven non-candidalysin Ece1 peptides (NCEPs), and is found to be conserved in clinical isolates. Here we show that the Ece1 polyprotein does not resemble the usual precursor structure of peptide toxins.

Candida albicans extracellular vesicles trigger type I IFN signalling via cGAS and STING.

The host type I interferon (IFN) pathway is a major signature of inflammation induced by the human fungal pathogen, Candida albicans. However, the molecular mechanism for activating this pathway in the host defence against C. albicans remains unknown.

Liposomal formulation of a new antifungal hybrid compound provides protection against in the skin colonization model.

The newly emerged pathogen, , presents a serious threat to public health worldwide. This multidrug-resistant yeast often colonizes and persists on the skin of patients, can easily spread from person to person, and can cause life-threatening systemic infections. New antifungal therapies are therefore urgently needed to limit and control both superficial and systemic infections.

Role of the extracellular matrix in Candida biofilm antifungal resistance.

Clinical infection due to Candida species frequently involve growth in biofilm communities. Recalcitrance despite antifungal therapy leads to disease persistence associated with high morbidity and mortality. Candida possesses several tools allowing evasion of antifungal effects.

A -specific adhesin, Scf1 governs surface association, colonization, and virulence.

is an emerging fungal pathogen responsible for health care-associated outbreaks that arise from persistent surface and skin colonization. We characterized the arsenal of adhesins used by and discovered an uncharacterized adhesin, Surface Colonization Factor (Scf1), and a conserved adhesin, Iff4109, that are essential for the colonization of inert surfaces and mammalian hosts. is apparently specific to , and its expression mediates adhesion to inert and biological surfaces across isolates from all five clades.

The reference strain SC5314 contains a rare, dominant allele of the transcription factor Rob1 that modulates filamentation, biofilm formation, and oral commensalism.

is a commensal fungus that colonizes the human oral cavity and gastrointestinal tract but also causes mucosal as well as invasive disease. The expression of virulence traits in clinical isolates is heterogeneous and the genetic basis of this heterogeneity is of high interest. The reference strain SC5314 is highly invasive and expresses robust filamentation and biofilm formation relative to many other clinical isolates.

The reference strain SC5314 contains a rare, dominant allele of the transcription factor Rob1 that modulates biofilm formation and oral commensalism.

Unlabelled: is a diploid human fungal pathogen that displays significant genomic and phenotypic heterogeneity over a range of virulence traits and in the context of a variety of environmental niches. Here, we show that the effects of Rob1 on biofilm and filamentation virulence traits is dependent on both the specific environmental condition and the clinical strain of . The reference strain SC5314 is a heterozygote with two alleles that differ by a single nucleotide polymorphism at position 946 resulting in a serine or proline containing isoform.

Aspergillus fumigatus transcription factor ZfpA regulates hyphal development and alters susceptibility to antifungals and neutrophil killing during infection.

Hyphal growth is essential for host colonization during Aspergillus infection. The transcription factor ZfpA regulates A. fumigatus hyphal development including branching, septation, and cell wall composition.

Novel Keto-Alkyl-Pyridinium Antifungal Molecules Active in Models of Candida albicans Vascular Catheter Infection and Candida auris Skin Colonization.

New antifungal therapies are needed for both systemic, invasive infections in addition to superficial infections of mucosal and skin surfaces as well as biofilms associated with medical devices. The resistance of biofilm and biofilm-like growth phases of fungi contributes to the poor efficacy of systemic therapies to nonsystemic infections. Here, we describe the identification and characterization of a novel keto-alkyl-pyridinium scaffold with broad spectrum activity (2 to 16 μg/mL) against medically important yeasts and molds, including clinical isolates resistant to azoles and/or echinocandins.

transcription factor ZfpA regulates hyphal development and alters susceptibility to antifungals and neutrophil killing during infection.

Unlabelled: Hyphal growth is essential for host colonization during infection. The transcription factor ZfpA regulates hyphal development including branching, septation, and cell wall composition. However, how ZfpA affects fungal growth and susceptibility to host immunity during infection has not been investigated.

Novel keto-alkyl-pyridinium antifungal molecules active in models of in vivo vascular catheter infection and ex vivo skin colonization.

New antifungal therapies are needed for both systemic, invasive infections as well as superficial infections of mucosal and skin surfaces as well as biofilms associated with medical devices. The resistance of biofilm and biofilm-like growth phases of fungi contributes to the poor efficacy of systemic therapies to non-systemic infections. Here, we describe the identification and characterization of a novel keto-alkyl-pyridinium scaffold with broad spectrum activity (2-16 µg/mL) against medically important yeasts and moulds, including clinical isolates resistant to azoles and/or echinocandins.

Reinforcement amid genetic diversity in the Candida albicans biofilm regulatory network.

Biofilms of the fungal pathogen Candida albicans include abundant long filaments called hyphae. These cells express hypha-associated genes, which specify diverse virulence functions including surface adhesins that ensure biofilm integrity. Biofilm formation, virulence, and hypha-associated gene expression all depend upon the transcription factor Efg1.

Extracellular Vesicles Contribute to Mixed-Fungal Species Competition during Biofilm Initiation.

Extracellular vesicles commonly modulate interactions among cellular communities. Recent studies demonstrate that biofilm maturation features, including matrix production, drug resistance, and dispersion, require the delivery of a core protein and carbohydrate vesicle cargo in species. The function of the vesicle cargo for these advanced-phase biofilm characteristics appears to be conserved across species.

A common vesicle proteome drives fungal biofilm development.

Extracellular vesicles mediate community interactions among cells ranging from unicellular microbes to complex vertebrates. Extracellular vesicles of the fungal pathogen are vital for biofilm communities to produce matrix, which confers environmental protection and modulates community dispersion. Infections are increasingly due to diverse species, such as the emerging pathogen , as well as mixed communities.

Recent developments in the biology and biotechnological applications of halotolerant yeasts.

Natural hypersaline environments are inhabited by an abundance of prokaryotic and eukaryotic microorganisms capable of thriving under extreme saline conditions. Yeasts represent a substantial fraction of halotolerant eukaryotic microbiomes and are frequently isolated as food contaminants and from solar salterns. During the last years, a handful of new species has been discovered in moderate saline environments, including estuarine and deep-sea waters.

Coordination of fungal biofilm development by extracellular vesicle cargo.

The fungal pathogen Candida albicans can form biofilms that protect it from drugs and the immune system. The biofilm cells release extracellular vesicles (EVs) that promote extracellular matrix formation and resistance to antifungal drugs. Here, we define functions for numerous EV cargo proteins in biofilm matrix assembly and drug resistance, as well as in fungal cell adhesion and dissemination.

Candida auris Cell Wall Mannosylation Contributes to Neutrophil Evasion through Pathways Divergent from Candida albicans and Candida glabrata.

Candida auris, a recently emergent fungal pathogen, has caused invasive infections in health care settings worldwide. Mortality rates approach 60% and hospital spread poses a public health threat. Compared to other spp.

Formation and characterization of biofilms formed by salt-tolerant yeast strains in seawater-based growth medium.

Yeast whole cells have been widely used in modern biotechnology as biocatalysts to generate numerous compounds of industrial, chemical, and pharmaceutical importance. Since many of the biocatalysis-utilizing manufactures have become more concerned about environmental issues, seawater is now considered a sustainable alternative to freshwater for biocatalytic processes. This approach plausibly commenced new research initiatives into exploration of salt-tolerant yeast strains.