Publications by authors named "Brakhage A"

The polyene antimycotic amphotericin B (AmB) and its liposomal formulation AmBisome belong to the treatment options of invasive aspergillosis caused by . Increasing resistance to AmB in clinical isolates of species is a growing concern, but mechanisms of AmB resistance remain unclear. In this study, we conducted a proteomic analysis of exposed to sublethal concentrations of AmB and AmBisome.

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Gene regulation at the post-transcriptional level is prevalent in all domains of life. In bacteria, ProQ-like proteins have emerged as important RNA chaperones facilitating RNA stability and RNA duplex formation. In the major human pathogen Vibrio cholerae, post-transcriptional gene regulation is key for virulence, biofilm formation, and antibiotic resistance, yet the role of ProQ has not been studied.

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Extracellular vesicles (EVs) have gained attention as facilitators of intercellular as well as interkingdom communication during host-microbe interactions. Recently we showed that upon infection, host polymorphonuclear leukocytes produce antifungal EVs targeting the clinically important fungal pathogen ; however, the small size of EVs (<1 µm) complicates their functional analysis. Here, we employed a more tractable, reporter-based system to label host alveolar epithelial cell-derived EVs and enable their visualization during interaction.

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can cause invasive pulmonary aspergillosis (IPA). Fungicidal azoles and fungistatic caspofungin (CAS) are the first- and second-line therapies, respectively, used to treat IPA. Treatment of with CAS or micafungin induces the production of the oxylipin 5,8-diHODE by the fungal oxygenase PpoA.

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Introduction: Influenza-associated pulmonary aspergillosis is associated with high mortality rates and limited treatment options. The current standard practice involves treating each pathogen separately. However, the use of antifungal drugs can lead to serious side effects, and the presence of triazole-resistant strains can complicate antifungal therapy.

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Microbiomes are shaped by abiotic factors like nutrients, oxygen availability, pH, temperature, and so on, but also by biotic factors including low molecular weight organic compounds referred to as natural products (NPs). Based on genome analyses, millions of these compounds are predicted to exist in nature, some of them have found important applications e.g.

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Gliotoxin (GT), a secondary metabolite and virulence factor of the fungal pathogen Aspergillus fumigatus, suppresses innate immunity and supports the suppression of host immune responses. Recently, we revealed that GT blocks the formation of the chemotactic lipid mediator leukotriene (LT)B in activated human neutrophils and monocytes, and in rodents in vivo, by directly inhibiting LTA hydrolase. Here, we elucidated the impact of GT on LTB biosynthesis and the entire lipid mediator networks in human M1- and M2-like monocyte-derived macrophages (MDMs) and in human tissue-resident alveolar macrophages.

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Nitrobenzothiazinones (BTZs) are undergoing late-stage development as a novel class of potent antitubercular drug candidates with two compounds in clinical phases. BTZs inhibit decaprenylphosphoryl-β-d-ribose oxidase 1 (DprE1), a key enzyme in cell wall biosynthesis of mycobacteria. Their mechanism of action involves an in-situ-reduction of the nitro moiety to a reactive nitroso intermediate capable of covalent binding to Cys387 in the catalytic cavity.

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Article Synopsis
  • Aspergillus fumigatus causes the infection known as aspergillosis and uses asexual spores to infect hosts, but little is known about how it evades the immune system.
  • In this study, researchers analyzed the conidial surface proteins of A. fumigatus and compared them to two non-pathogenic species, discovering 62 proteins unique to A. fumigatus.
  • Testing null mutants for 42 genes revealed that deleting 33 of these genes affected the fungus's ability to resist immune responses, particularly highlighting a gene that influences the proinflammatory cytokine IL-1β, which is crucial for infection in a mouse model.
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An important host defence mechanism against pathogens is intracellular killing, which is achieved through phagocytosis, a cellular process for engulfing and neutralizing extracellular particles. Phagocytosis results in the formation of matured phagolysosomes, which are specialized compartments that provide a hostile environment and are considered the end point of the degradative pathway. However, all fungal pathogens studied to date have developed strategies to manipulate phagosomal function directly and also indirectly by redirecting phagosomes from the degradative pathway to a non-degradative pathway with the expulsion and even transfer of pathogens between cells.

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  • PTX3 is a protective molecule that interacts with the fungus Aspergillus fumigatus in different ways, depending on the fungal form (germinating vs. dormant conidia).
  • It recognizes germinating conidia through a specific polysaccharide and interacts with dormant conidia through weak binding with surface proteins, while other proteins (SP-D, C1q, C3b) enhance this interaction.
  • PTX3 helps regulate inflammation by reducing the production of pro-inflammatory signals and increasing anti-inflammatory signals like IL-10 in immune responses related to aspergillosis and potentially serves as a biomarker for certain fungal infections.
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  • * Researchers created a library of 111 genetically modified Aspergillus fumigatus mutants to identify important antifungal targets, discovering that a specific kinase, YakA, is crucial for regulating susceptibility to azoles and pathogenicity.
  • * The study found that inhibiting YakA not only weakens the fungus's ability to grow and invade tissues but also enhances the effectiveness of azoles when combined with a compound (1-ECBC), suggesting a potential avenue for improving treatment.
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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.

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The SNF1 protein kinase signaling pathway, which is highly conserved in eukaryotic cells, is important for metabolic adaptations in the pathogenic yeast . However, so far, it has remained elusive how SNF1 controls the activity of one of its main effectors, the repressor protein Mig1 that inhibits the expression of genes required for the utilization of alternative carbon sources when glucose is available. In this study, we have identified multiple phosphorylation sites in Mig1 that contribute to its inactivation.

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Seasonal influenza A virus (IAV) infections still pose a major burden for public health worldwide. Severe disease progression or even death is often related to superinfections of the virus and a secondary bacterial pathogen. However, fungi, especially Aspergillus fumigatus, are also frequently diagnosed during IAV infection.

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Background: Aspergillus fumigatus is a major fungal pathogen that causes severe problems due to its increasing resistance to many therapeutic agents. Fludioxonil is a compound that triggers a lethal activation of the fungal-specific High Osmolarity Glycerol pathway. Its pronounced antifungal activity against A.

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, an important pulmonary fungal pathogen causing several diseases collectively called aspergillosis, relies on asexual spores (conidia) for initiating host infection. Here, we used a phylogenomic approach to compare proteins in the conidial surface of , two closely related non-pathogenic species, and , and the cryptic pathogen . After identifying 62 proteins uniquely expressed on the conidial surface, we assessed null mutants for 42 genes encoding conidial proteins.

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Aberrant CD4 T cell reactivity against intestinal microorganisms is considered to drive mucosal inflammation in inflammatory bowel diseases. The disease-relevant microbial species and the corresponding microorganism-specific, pathogenic T cell phenotypes remain largely unknown. In the present study, we identified common gut commensal and food-derived yeasts, as direct activators of altered CD4 T cell reactions in patients with Crohn's disease (CD).

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Article Synopsis
  • The study investigates the role of conidial surface proteins in the pathogenic fungus responsible for aspergillosis and compares it with non-pathogenic species.
  • Researchers identified 62 proteins specifically expressed on the surface of the conidia and deleted genes for 42 of these proteins to assess their impact on infection.
  • Findings indicate that certain proteins, particularly one related to IL-1β production, are crucial for the fungus in evading the immune response during initial host infection.
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The soft rot pathogen causes devastating damage to button mushrooms (), one of the most cultivated and commercially relevant mushrooms. We previously discovered that this pathogen releases the membrane-disrupting lipopeptide jagaricin. This bacterial toxin, however, could not solely explain the rapid decay of mushroom fruiting bodies, indicating that implements a more sophisticated infection strategy.

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  • Aspergillus fumigatus is an opportunistic pathogen that often infects the lungs of cystic fibrosis patients and poses a significant risk to immunocompromised individuals, leading to high rates of infectious disease-related deaths.
  • Researchers developed 252 strain-specific, genome-scale metabolic models of A. fumigatus, revealing that over 23% of its metabolic reactions vary between strains, particularly in amino acid, nucleotide, and nitrogen metabolism.
  • Analysis of sputum from cystic fibrosis patients indicates that A. fumigatus influences the lung microbiome, promoting conditions favorable for its growth, which could guide future drug development or microbiome interventions targeting this fungus.
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More than 10 million people suffer from lung diseases caused by the pathogenic fungus . The azole class of antifungals represent first line therapeutics for most of these infections however resistance is rising. Identification of novel antifungal targets that, when inhibited, synergise with the azoles will aid the development of agents that can improve therapeutic outcomes and supress the emergence of resistance.

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Although the interaction between prokaryotic and eukaryotic microorganisms is crucial for the functioning of ecosystems, information about the processes driving microbial interactions within communities remains scarce. Here we show that arginine-derived polyketides (arginoketides) produced by Streptomyces species mediate cross-kingdom microbial interactions with fungi of the genera Aspergillus and Penicillium, and trigger the production of natural products. Arginoketides can be cyclic or linear, and a prominent example is azalomycin F produced by Streptomyces iranensis, which induces the cryptic orsellinic acid gene cluster in Aspergillus nidulans.

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Aging is a major risk factor associated with increased morbidity and mortality rates observed during respiratory infections. In this study, we investigated the role of influenza virus infections in the establishment of premature cellular senescence and paracrine macrophage-activated inflammation. We observed in our murine model a premature aging by the appearance of senescent cells in the lungs after 21 d of influenza A virus infection.

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