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1.
Commun Biol ; 7(1): 735, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38890525

RESUMO

Utilizing a microfluidic chip with serpentine channels, we inoculated the chip with an agar plug with Neurospora crassa mycelium and successfully captured individual hyphae in channels. For the first time, we report the presence of an autonomous clock in hyphae. Fluorescence of a mCherry reporter gene driven by a clock-controlled gene-2 promoter (ccg-2p) was measured simultaneously along hyphae every half an hour for at least 6 days. We entrained single hyphae to light over a wide range of day lengths, including 6,12, 24, and 36 h days. Hyphae tracked in individual serpentine channels were highly synchronized (K = 0.60-0.78). Furthermore, hyphae also displayed temperature compensation properties, where the oscillation period was stable over a physiological range of temperatures from 24 °C to 30 °C (Q10 = 1.00-1.10). A Clock Tube Model developed could mimic hyphal growth observed in the serpentine chip and provides a mechanism for the stable banding patterns seen in race tubes at the macroscopic scale and synchronization through molecules riding the growth wave in the device.


Assuntos
Hifas , Neurospora crassa , Neurospora crassa/genética , Neurospora crassa/fisiologia , Neurospora crassa/crescimento & desenvolvimento , Hifas/crescimento & desenvolvimento , Hifas/genética , Temperatura , Dispositivos Lab-On-A-Chip , Regulação Fúngica da Expressão Gênica , Relógios Biológicos/genética
2.
Fungal Biol ; 128(4): 1868-1875, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38876539

RESUMO

In the development of fungal based materials for applications in construction through to biomedical materials and fashion, understanding how to regulate and direct growth is key for gaining control over the form of material generated. Here, we show how simple 'chemical food' cues can be used to manipulate the growth of fungal networks by taking Aspergillus niger as an exemplar species. Chemotrophic responses towards a range of nitrogen and carbon containing biomolecules including amino acids, sugars and sugar alcohols were quantified in terms of chemotrophic index (CI) under a range of basal media compositions (low and high concentrations of N and C sources). Growth of filamentous networks was followed using fluorescence microscopy at single time points and during growth by an AI analytical approach to explore chemo sensing behaviour of the fungus when exposed to pairs (C-C, C-N, N-N) of biomolecules simultaneously. Data suggests that the directive growth of A. niger can be controlled towards simple biomolecules with CI values giving a good approximation for expected growth under a range of growth conditions. This is a first step towards identifying conditions for researcher-led directed growth of hyphae to make mycelial mats with tuneable morphological, physicochemical, and mechanical characteristics.


Assuntos
Aspergillus niger , Meios de Cultura , Hifas , Nitrogênio , Aspergillus niger/crescimento & desenvolvimento , Aspergillus niger/metabolismo , Hifas/crescimento & desenvolvimento , Meios de Cultura/química , Nitrogênio/metabolismo , Carbono/metabolismo , Aminoácidos/metabolismo , Microscopia de Fluorescência
3.
Microbes Environ ; 39(2)2024.
Artigo em Inglês | MEDLINE | ID: mdl-38866480

RESUMO

Mn(II)-oxidizing microorganisms are considered to play significant roles in the natural geochemical cycles of Mn and other heavy metals because the insoluble biogenic Mn oxides (BMOs) that are produced by these microorganisms adsorb other dissolved heavy metals and immobilize them as precipitates. In the present study, a new Mn(II)-oxidizing fungal strain belonging to the ascomycete genus Periconia, a well-studied plant-associating fungal genus with Mn(II)-oxidizing activity that has not yet been exami-ned in detail, was isolated from natural groundwater outflow sediment. This isolate, named strain TS-2, was confirmed to oxidize dissolved Mn(II) and produce insoluble BMOs that formed characteristic, separately-located nodules on their hyphae while leaving major areas of the hyphae free from encrustation. These BMO nodules also adsorbed and immobilized dissolved Cu(II), a model analyte of heavy metals, as evidenced by elemental mapping ana-lyses of fungal hyphae-BMO assemblages using a scanning electron microscope with energy-dispersive X-ray spectroscopy (SEM-EDX). Analyses of functional genes within the whole genome of strain TS-2 further revealed the presence of multiple genes predicted to encode laccases/multicopper oxidases that were potentially responsible for Mn(II) oxidation by this strain. The formation of BMO nodules may have functioned to prevent the complete encrustation of fungal hyphae, thereby enabling the control of heavy metal concentrations in their local microenvironments while maintaining hyphal functionality. The present results will expand our knowledge of the physiological and morphological traits of Mn(II)-oxidizing Periconia, which may affect the natural cycle of heavy metals through their immobilization.


Assuntos
Cobre , Hifas , Compostos de Manganês , Óxidos , Hifas/metabolismo , Hifas/crescimento & desenvolvimento , Cobre/metabolismo , Compostos de Manganês/metabolismo , Óxidos/metabolismo , Óxidos/química , Ascomicetos/genética , Ascomicetos/metabolismo , Ascomicetos/química , Oxirredução , Água Subterrânea/microbiologia , Água Subterrânea/química , Filogenia , Sedimentos Geológicos/microbiologia , Microscopia Eletrônica de Varredura , Manganês/metabolismo
5.
Cell Host Microbe ; 32(6): 779-781, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38870893

RESUMO

In a recent issue of Nature, Zhao et al. have demonstrated that Streptomyces spp. produce "umbrella"-shaped polymorphic toxin particles, a novel class of non-lethal toxins that gently inhibit competitors by arresting hyphal growth in closely related bacteria, unveiling a unique bacterial defense strategy in microbial ecological interactions.1.


Assuntos
Toxinas Bacterianas , Streptomyces , Streptomyces/metabolismo , Toxinas Bacterianas/metabolismo , Toxinas Bacterianas/toxicidade , Antibiose , Hifas/crescimento & desenvolvimento , Interações Microbianas
6.
Virulence ; 15(1): 2362748, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38860453

RESUMO

Rad6 functions as a ubiquitin-conjugating protein that regulates cellular processes in many fungal species. However, its role in filamentous entomopathogenic fungi remains poorly understood. This study characterizes Rad6 in Beauveria bassiana, a filamentous fungus widely employed as a critical fungicide globally. The results demonstrate a significant association between Rad6 and conidial properties, heat shock response, and UV-B tolerance. Concurrently, the mutant strain exhibited heightened sensitivity to oxidative stress, cell wall interfering agents, DNA damage stress, and prolonged heat shock. Furthermore, the absence of Rad6 significantly extended the median lethal time (LT50) of Galleria mellonella infected by B. bassiana. This delay could be attributed to reduced Pr1 proteases and extracellular cuticle-degrading enzymes, diminished dimorphic transition rates, and dysregulated antioxidant enzymes. Additionally, the absence of Rad6 had a more pronounced effect on genetic information processing, metabolism, and cellular processes under normal conditions. However, its impact was limited to metabolism in oxidative stress. This study offers a comprehensive understanding of the pivotal roles of Rad6 in conidial and hyphal stress tolerance, environmental adaptation, and the pathogenesis of Beauveria bassiana.


Assuntos
Beauveria , Proteínas Fúngicas , Estresse Oxidativo , Esporos Fúngicos , Beauveria/patogenicidade , Beauveria/genética , Beauveria/fisiologia , Animais , Esporos Fúngicos/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Virulência , Estresse Fisiológico , Mariposas/microbiologia , Enzimas de Conjugação de Ubiquitina/metabolismo , Enzimas de Conjugação de Ubiquitina/genética , Resposta ao Choque Térmico , Hifas/crescimento & desenvolvimento
7.
Sci Rep ; 14(1): 13797, 2024 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-38877139

RESUMO

In filamentous fungi, microtubules are important for polar growth and morphological maintenance and serve as rails for intracellular trafficking. The molecular mechanisms associated with microtubules have been analyzed. However, little is known about when and where tubulin, a component of microtubules, is biosynthesized in multinuclear and multicellular filamentous fungi. In this study, we visualized microtubules based on the enhanced green fluorescence protein (EGFP)-labeled α-tubulin and ß-tubulin mRNA tagged by the EGFP-mediated MS2 system in living yellow Koji mold Aspergillus oryzae cells in order to understand the spatiotemporal production mechanism of tubulin. We found that mRNA of btuA, encoding for ß-tubulin, localized at dot-like structures through the apical, middle and basal regions of the hyphal cells. In addition, some btuA mRNA dots showed microtubule-dependent motor protein-like dynamics in the cells. Furthermore, it was found that btuA mRNA dots were decreased in the cytoplasm just before mitosis but increased immediately after mitosis, followed by a gradual decrease. In summary, the localization and abundance of ß-tubulin mRNA is spatiotemporally regulated in living A. oryzae hyphal cells.


Assuntos
Aspergillus oryzae , Microtúbulos , RNA Mensageiro , Tubulina (Proteína) , Aspergillus oryzae/genética , Aspergillus oryzae/metabolismo , Tubulina (Proteína)/genética , Tubulina (Proteína)/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Microtúbulos/metabolismo , Hifas/genética , Hifas/metabolismo , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Regulação Fúngica da Expressão Gênica , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo
8.
Nat Commun ; 15(1): 4131, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38755250

RESUMO

The transition between yeast and hyphae is crucial for regulating the commensalism and pathogenicity in Candida albicans. The mechanisms that affect the invasion of hyphae in solid media, whose deficiency is more related to the pathogenicity of C. albicans, have not been elucidated. Here, we found that the disruption of VAM6 or VPS41 which are components of the homotypic vacuolar fusion and protein sorting (HOPS) complex, or the Rab GTPase YPT72, all responsible for vacuole fusion, led to defects in hyphal growth in both liquid and solid media, but more pronounced on solid agar. The phenotypes of vac8Δ/Δ and GTR1OE-vam6Δ/Δ mutants indicated that these deficiencies are mainly caused by the reduced mechanical forces that drive agar and organs penetration, and confirmed that large vacuoles are required for hyphal mechanical penetration. In summary, our study revealed that large vacuoles generated by vacuolar fusion support hyphal penetration and provided a perspective to refocus attention on the role of solid agar in evaluating C. albicans invasion.


Assuntos
Candida albicans , Proteínas Fúngicas , Hifas , Vacúolos , Candida albicans/metabolismo , Candida albicans/genética , Hifas/metabolismo , Hifas/crescimento & desenvolvimento , Hifas/genética , Vacúolos/metabolismo , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , Animais , Camundongos , Proteínas rab de Ligação ao GTP/metabolismo , Proteínas rab de Ligação ao GTP/genética , Candidíase/microbiologia , Proteínas de Transporte Vesicular/metabolismo , Proteínas de Transporte Vesicular/genética , Feminino , Fusão de Membrana
9.
Med Mycol ; 62(5)2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38692846

RESUMO

Candida albicans is a pathogenic fungus that undergoes morphological transitions between hyphal and yeast forms, adapting to diverse environmental stimuli and exhibiting distinct virulence. Existing research works on antifungal blue light (ABL) therapy have either focused solely on hyphae or neglected to differentiate between morphologies, obscuring potential differential effects. To address this gap, we established a novel dataset of 150 C. albicans-infected mouse skin tissue slice images with meticulously annotated hyphae and yeast. Eleven representative convolutional neural networks were trained and evaluated on this dataset using seven metrics to identify the optimal model for segmenting hyphae and yeast in original high pixel size images. Leveraging the segmentation results, we analyzed the differential impact of blue light on the invasion depth and density of both morphologies within the skin tissue. U-Net-BN outperformed other models in segmentation accuracy, achieving the best overall performance. While both hyphae and yeast exhibited significant reductions in invasion depth and density at the highest ABL dose (180 J/cm2), only yeast was significantly inhibited at the lower dose (135 J/cm2). This novel finding emphasizes the importance of developing more effective treatment strategies for both morphologies.


We studied the effects of blue light therapy on hyphal and yeast forms of Candida albicans. Through image segmentation techniques, we discovered that the changes in invasion depth and density differed between these two forms after exposure to blue light.


Assuntos
Candida albicans , Hifas , Animais , Camundongos , Candida albicans/efeitos da radiação , Pele/microbiologia , Fototerapia/métodos , Processamento de Imagem Assistida por Computador/métodos , Luz , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Redes Neurais de Computação , Modelos Animais de Doenças , Candidíase/microbiologia
10.
Microbiol Res ; 285: 127742, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38723390

RESUMO

In recent years, numerous oomycete mycoviruses have been discovered; however, very few studies have focused on their effects on the host oomycete phenotype. In this study, we investigated the impact of toti-like Pythium ultimum RNA virus 2 (PuRV2) infection on the phytopathogenic soil-borne oomycete Globisporangium ultimum, which serves as a model species for Globisporangium and Pythium, specifically the UOP226 isolate in Japan. We generated a PuRV2-free isogenic line through hyphal tip isolation using high-temperature culture and subsequently compared the phenotypic characteristics and gene expression profiles of UOP226 and the PuRV2-free isogenic line. Our findings revealed that the metalaxyl sensitivity of UOP226 was greater than that of the PuRV2-free isogenic line, whereas the mycelial growth rate and colony morphology remained unchanged in the absence of the fungicide. Furthermore, transcriptome analyses using RNA-seq revealed significant downregulation of ABC-type transporter genes, which are involved in fungicide sensitivity, in UOP226. Our results suggest that PuRV2 infection influences the ecology of G. ultimum in agricultural ecosystems where metalaxyl is applied.


Assuntos
Alanina , Micovírus , Fungicidas Industriais , Doenças das Plantas , Vírus de RNA , Fungicidas Industriais/farmacologia , Micovírus/genética , Micovírus/fisiologia , Micovírus/isolamento & purificação , Micovírus/efeitos dos fármacos , Alanina/análogos & derivados , Alanina/farmacologia , Doenças das Plantas/microbiologia , Doenças das Plantas/virologia , Vírus de RNA/efeitos dos fármacos , Vírus de RNA/genética , Pythium/efeitos dos fármacos , Pythium/crescimento & desenvolvimento , Hifas/crescimento & desenvolvimento , Hifas/efeitos dos fármacos , Perfilação da Expressão Gênica , Micélio/crescimento & desenvolvimento , Micélio/efeitos dos fármacos , Micélio/virologia , Japão , Transcriptoma
11.
mBio ; 15(6): e0350423, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38747587

RESUMO

Successful host tissue colonization is crucial for fungal pathogens to cause mycosis and complete the infection cycle, in which fungal cells undergo a series of morphological transition-included cellular events to combat with hosts. However, many transcription factors (TFs) and their mediated networks regulating fungal pathogen colonization of host tissue are not well characterized. Here, a TF (BbHCR1)-mediated regulatory network was identified in an insect pathogenic fungus, Beauveria bassiana, that controlled insect hemocoel colonization. BbHCR1 was highly expressed in fungal cells after reaching insect hemocoel and controlled the yeast (in vivo blastospores)-to-hyphal morphological switch, evasion of immune defense response, and fungal virulence. Comparative analysis of RNA sequencing and chromatin immunoprecipitation sequencing identified a core set of BbHCR1 target genes during hemocoel colonization, in which abaA and brlA were targeted to limit the rapid switch from blastospores to hyphae and fungal virulence. Two targets encoding hypothetical proteins, HP1 and HP2, were activated and repressed by BbHCR1, respectively, which acted as a virulence factor and repressor, respectively, suggesting that BbHCR1 activated virulence factors but repressed virulence repressors during the colonization of insect hemocoel. BbHCR1 tuned the expression of two dominant hemocoel colonization-involved metabolite biosynthetic gene clusters, which linked its regulatory role in evasion of immune response. Those functions of BbHCR1 were found to be collaboratively regulated by Fus3- and Hog1-MAP kinases via phosphorylation. These findings have drawn a regulatory network in which Fus3- and Hog1-MAP kinases phosphorylate BbHCR1, which in turn controls the colonization of insect body cavities by regulating fungal morphological transition and virulence-implicated genes.IMPORTANCEFungal pathogens adopt a series of tactics for successful colonization in host tissues, which include morphological transition and the generation of toxic and immunosuppressive molecules. However, many transcription factors (TFs) and their linked pathways that regulate tissue colonization are not well characterized. Here, we identified a TF (BbHCR1)-mediated regulatory network that controls the insect fungal pathogen, Beauveria bassiana, colonization of insect hemocoel. During these processes, BbHCR1 targeted the fungal central development pathway for the control of yeast (blastospores)-to-hyphae morphological transition, activated virulence factors, repressed virulence repressors, and tuned the expression of two dominant hemocoel colonization-involved immunosuppressive and immunostimulatory metabolite biosynthetic gene clusters. The BbHCR1 regulatory function was governed by Fus3- and Hog1-MAP kinases. These findings led to a new regulatory network composed of Fus3- and Hog1-MAP kinases and BbHCR1 that control insect body cavity colonization by regulating fungal morphological transition and virulence-implicated genes.


Assuntos
Beauveria , Proteínas Fúngicas , Regulação Fúngica da Expressão Gênica , Redes Reguladoras de Genes , Fatores de Transcrição , Animais , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Beauveria/genética , Beauveria/patogenicidade , Virulência , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Fatores de Virulência/genética , Fatores de Virulência/metabolismo , Insetos/microbiologia , Hifas/crescimento & desenvolvimento , Hifas/genética , Interações Hospedeiro-Patógeno
12.
PLoS Pathog ; 20(5): e1012225, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38739655

RESUMO

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. In both in vitro and in vivo biofilm contexts, cell number is reduced and hyphal length is limited. To determine whether the mutant defect is in growth or some other aspect of biofilm development, we examined planktonic cell features in a biofilm-like environment, which was approximated with sealed unshaken cultures. Under those conditions, the erg251Δ/Δ mutation causes defects in growth and hyphal extension. Overexpression in the erg251Δ/Δ mutant of the paralog ERG25, which is normally expressed more weakly than ERG251, partially improves biofilm formation and biofilm hyphal content, as well as growth and hyphal extension in a biofilm-like environment. GC-MS analysis shows that the erg251Δ/Δ mutation causes a defect in ergosterol accumulation when cells are cultivated under biofilm-like conditions, but not under conventional planktonic conditions. Overexpression of ERG25 in the erg251Δ/Δ mutant causes some increase in ergosterol levels. Finally, the hypersensitivity of efg1Δ/Δ mutants to the ergosterol inhibitor fluconazole is reversed by ERG251 overexpression, arguing that reduced ERG251 expression contributes to this efg1Δ/Δ phenotype. Our results indicate that ERG251 is required for biofilm formation because its high expression levels are necessary for ergosterol synthesis in a biofilm-like environment.


Assuntos
Biofilmes , Candida albicans , Candidíase , Proteínas Fúngicas , Biofilmes/crescimento & desenvolvimento , Candida albicans/metabolismo , Candida albicans/genética , Candida albicans/fisiologia , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , Animais , Candidíase/microbiologia , Candidíase/metabolismo , Hifas/metabolismo , Camundongos , Regulação Fúngica da Expressão Gênica , Ergosterol/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Mutação
13.
Arch Microbiol ; 206(6): 251, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38727840

RESUMO

The prevalence of Candida albicans infection has increased during the past few years, which contributes to the need for new, effective treatments due to the increasing concerns regarding antifungal drug toxicity and multidrug resistance. Butyl isothiocyanate (butylITC) is a glucosinolate derivative, and has shown a significant antifungal effect contrary to Candida albicans. Additionally, how butylITC affects the virulence traits of C. albicans and molecular mode of actions are not well known. Present study shows that at 17.36 mM concentration butylITC inhibit planktonic growth. butylITC initially slowed the hyphal transition at 0.542 mM concentration. butylITC hampered biofilm development, and inhibits biofilm formation at 17.36 mM concentration which was analysed using metabolic assay (XTT assay) and Scanning Electron Microscopy (SEM). In addition, it was noted that butylITC inhibits ergosterol biosynthesis. The permeability of cell membranes was enhanced by butylITC treatment. Moreover, butylITC arrests cells at S-phase and induces intracellular Reactive Oxygen Species (ROS) accumulation in C. albicans. The results suggest that butylITC may have a dual mode of action, inhibit virulence factors and modulate cellular processes like inhibit ergosterol biosynthesis, cell cycle arrest, induces ROS production which leads to cell death in C. albicans.


Assuntos
Antifúngicos , Biofilmes , Candida albicans , Membrana Celular , Isotiocianatos , Estresse Oxidativo , Espécies Reativas de Oxigênio , Candida albicans/efeitos dos fármacos , Candida albicans/fisiologia , Biofilmes/efeitos dos fármacos , Antifúngicos/farmacologia , Isotiocianatos/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Testes de Sensibilidade Microbiana , Ciclo Celular/efeitos dos fármacos , Hifas/efeitos dos fármacos , Hifas/crescimento & desenvolvimento , Ergosterol/metabolismo
14.
Nat Commun ; 15(1): 4486, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38802389

RESUMO

Bacterial-fungal interactions influence microbial community performance of most ecosystems and elicit specific microbial behaviours, including stimulating specialised metabolite production. Here, we use a co-culture experimental evolution approach to investigate bacterial adaptation to the presence of a fungus, using a simple model of bacterial-fungal interactions encompassing the bacterium Bacillus subtilis and the fungus Aspergillus niger. We find in one evolving population that B. subtilis was selected for enhanced production of the lipopeptide surfactin and accelerated surface spreading ability, leading to inhibition of fungal expansion and acidification of the environment. These phenotypes were explained by specific mutations in the DegS-DegU two-component system. In the presence of surfactin, fungal hyphae exhibited bulging cells with delocalised secretory vesicles possibly provoking an RlmA-dependent cell wall stress. Thus, our results indicate that the presence of the fungus selects for increased surfactin production, which inhibits fungal growth and facilitates the competitive success of the bacterium.


Assuntos
Adaptação Fisiológica , Aspergillus niger , Bacillus subtilis , Lipopeptídeos , Bacillus subtilis/fisiologia , Bacillus subtilis/metabolismo , Bacillus subtilis/genética , Bacillus subtilis/crescimento & desenvolvimento , Aspergillus niger/metabolismo , Aspergillus niger/fisiologia , Aspergillus niger/crescimento & desenvolvimento , Lipopeptídeos/metabolismo , Peptídeos Cíclicos/metabolismo , Hifas/crescimento & desenvolvimento , Hifas/metabolismo , Interações Microbianas/fisiologia , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Técnicas de Cocultura , Mutação , Parede Celular/metabolismo
15.
Mol Biol Cell ; 35(7): ar99, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38776129

RESUMO

The human fungal pathogen Candida albicans can cause lethal systemic infections due to its ability to resist stress from the host and to undergo invasive hyphal growth. Previous studies showed that plasma membrane MCC/eisosome domains were important for virulence by promoting the ability of Sur7 to mediate normal cell wall morphogenesis and stress resistance. The sur7Δ mutant displayed abnormal clusters of PI4,5P2, suggesting that misregulation of this lipid underlies the sur7Δ phenotype. To test this, we increased PI4,5P2 levels by deleting combinations of the three PI4,5P2 5' phosphatase genes (INP51, INP52, and INP54) and found that some combinations, such as inp51Δ inp52Δ, gave phenotypes similar the sur7Δ mutant. In contrast, deleting one copy of MSS4, the gene that encodes the 5' kinase needed to create PI4,5P2, reduced the abnormal PI4,5P2 clusters and also decreased the abnormal cell wall and stress sensitive phenotypes of the sur7Δ mutant. Additional studies support a model that the abnormal PI4,5P2 patches recruit septin proteins, which in turn promote aberrant cell wall growth. These results identify Sur7 as a novel regulator of PI4,5P2 and highlight the critical role of PI4,5P2 in the regulation of C. albicans virulence properties.


Assuntos
Candida albicans , Parede Celular , Proteínas Fúngicas , Morfogênese , Candida albicans/metabolismo , Candida albicans/patogenicidade , Candida albicans/genética , Candida albicans/fisiologia , Parede Celular/metabolismo , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , Virulência , Estresse Fisiológico , Fosfatidilinositol 4,5-Difosfato/metabolismo , Hifas/metabolismo , Membrana Celular/metabolismo , Regulação Fúngica da Expressão Gênica , Monoéster Fosfórico Hidrolases/metabolismo , Monoéster Fosfórico Hidrolases/genética
16.
PLoS Genet ; 20(5): e1011282, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38768261

RESUMO

Light as a source of information regulates morphological and physiological processes of fungi, including development, primary and secondary metabolism, or the circadian rhythm. Light signaling in fungi depends on photoreceptors and downstream components that amplify the signal to govern the expression of an array of genes. Here, we investigated the effects of red and far-red light in the mycoparasite Trichoderma guizhouense on its mycoparasitic potential. We show that the invasion strategy of T. guizhouense depends on the attacked species and that red and far-red light increased aerial hyphal growth and led to faster overgrowth or invasion of the colonies. Molecular experiments and transcriptome analyses revealed that red and far-red light are sensed by phytochrome FPH1 and further transmitted by the downstream MAPK HOG pathway and the bZIP transcription factor ATF1. Overexpression of the red- and far-red light-induced fluffy gene fluG in the dark resulted in abundant aerial hyphae formation and thereby improvement of its antagonistic ability against phytopathogenic fungi. Hence, light-induced fluG expression is important for the mycoparasitic interaction. The increased aggressiveness of fluG-overexpressing strains was phenocopied by four random mutants obtained after UV mutagenesis. Therefore, aerial hyphae formation appears to be a trait for the antagonistic potential of T. guizhouense.


Assuntos
Regulação Fúngica da Expressão Gênica , Hifas , Luz , Fitocromo , Trichoderma , Hifas/crescimento & desenvolvimento , Hifas/genética , Fitocromo/metabolismo , Fitocromo/genética , Trichoderma/genética , Trichoderma/fisiologia , Trichoderma/crescimento & desenvolvimento , Doenças das Plantas/microbiologia , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , Ascomicetos/genética , Ascomicetos/crescimento & desenvolvimento , Rhizoctonia/crescimento & desenvolvimento , Luz Vermelha
17.
Nat Commun ; 15(1): 4261, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38769341

RESUMO

Triazoles, the most widely used class of antifungal drugs, inhibit the biosynthesis of ergosterol, a crucial component of the fungal plasma membrane. Inhibition of a separate ergosterol biosynthetic step, catalyzed by the sterol C-24 methyltransferase Erg6, reduces the virulence of pathogenic yeasts, but its effects on filamentous fungal pathogens like Aspergillus fumigatus remain unexplored. Here, we show that the lipid droplet-associated enzyme Erg6 is essential for the viability of A. fumigatus and other Aspergillus species, including A. lentulus, A. terreus, and A. nidulans. Downregulation of erg6 causes loss of sterol-rich membrane domains required for apical extension of hyphae, as well as altered sterol profiles consistent with the Erg6 enzyme functioning upstream of the triazole drug target, Cyp51A/Cyp51B. Unexpectedly, erg6-repressed strains display wild-type susceptibility against the ergosterol-active triazole and polyene antifungals. Finally, we show that erg6 repression results in significant reduction in mortality in a murine model of invasive aspergillosis. Taken together with recent studies, our work supports Erg6 as a potentially pan-fungal drug target.


Assuntos
Antifúngicos , Aspergilose , Aspergillus , Ergosterol , Proteínas Fúngicas , Metiltransferases , Triazóis , Animais , Metiltransferases/metabolismo , Metiltransferases/genética , Antifúngicos/farmacologia , Aspergillus/genética , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , Camundongos , Aspergilose/microbiologia , Aspergilose/tratamento farmacológico , Ergosterol/metabolismo , Ergosterol/biossíntese , Triazóis/farmacologia , Regulação Fúngica da Expressão Gênica , Aspergillus fumigatus/genética , Aspergillus fumigatus/efeitos dos fármacos , Aspergillus fumigatus/enzimologia , Aspergillus fumigatus/metabolismo , Hifas/efeitos dos fármacos , Hifas/crescimento & desenvolvimento , Hifas/genética , Hifas/metabolismo , Feminino , Testes de Sensibilidade Microbiana , Virulência/genética
18.
PLoS One ; 19(5): e0303449, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38768097

RESUMO

Candida albicans (C. albicans) can behave as a commensal yeast colonizing the vaginal mucosa, and in this condition is tolerated by the epithelium. When the epithelial tolerance breaks down, due to C. albicans overgrowth and hyphae formation, the generated inflammatory response and cell damage lead to vulvovaginal candidiasis (VVC) symptoms. Here, we focused on the induction of mitochondrial reactive oxygen species (mtROS) in vaginal epithelial cells after C. albicans infection and the involvement of fungal burden, morphogenesis and candidalysin (CL) production in such induction. Bioluminescent (BLI) C. albicans, C. albicans PCA-2 and C. albicans 529L strains were employed in an in vitro infection model including reconstituted vaginal epithelium cells (RVE), produced starting from A-431 cell line. The production of mtROS was kinetically measured by using MitoSOX™ Red probe. The potency of C. albicans to induced cell damage to RVE and C. albicans proliferation have also been evaluated. C. albicans induces a rapid mtROS release from vaginal epithelial cells, in parallel with an increase of the fungal load and hyphal formation. Under the same experimental conditions, the 529L C. albicans strain, known to be defective in CL production, induced a minor mtROS release showing the key role of CL in causing epithelial mithocondrial activation. C. albicans PCA-2, unable to form hyphae, induced comparable but slower mtROS production as compared to BLI C. albicans yeasts. By reducing mtROS through a ROS scavenger, an increased fungal burden was observed during RVE infection but not in fungal cultures grown on abiotic surface. Collectively, we conclude that CL, more than fungal load and hyphae formation, seems to play a key role in the rapid activation of mtROS by epithelial cells and in the induction of cell-damage and that mtROS are key elements in the vaginal epithelial cells response to C. albicans.


Assuntos
Candida albicans , Candidíase Vulvovaginal , Células Epiteliais , Proteínas Fúngicas , Mitocôndrias , Espécies Reativas de Oxigênio , Vagina , Candida albicans/metabolismo , Candida albicans/fisiologia , Feminino , Humanos , Mitocôndrias/metabolismo , Vagina/microbiologia , Espécies Reativas de Oxigênio/metabolismo , Células Epiteliais/microbiologia , Células Epiteliais/metabolismo , Proteínas Fúngicas/metabolismo , Candidíase Vulvovaginal/microbiologia , Hifas/metabolismo , Hifas/crescimento & desenvolvimento , Linhagem Celular
19.
Arch Microbiol ; 206(5): 235, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38722413

RESUMO

In recent years, blueberry root rot has been caused mainly by Fusarium commune, and there is an urgent need for a green and efficient method to control this disease. To date, research on Schizophyllum commune has focused on antioxidant mechanisms, reactive dye degradation, etc., but the mechanism underlying the inhibition of pathogenic microorganisms is still unclear. Here, the control effects of S. commune on F. commune and blueberry root rot were studied using adversarial culture, tissue culture, and greenhouse pot experiments. The results showed that S. commune can dissolve insoluble phosphorus and secrete various extracellular hydrolases. The results of hyphal confrontation and fermentation broth antagonism experiments showed that S. commune had a significant inhibitory effect on F. commune, with inhibition rates of 70.30% and 22.86%, respectively. Microscopy results showed distortion of F. commune hyphae, indicating that S. commune is strongly parasitic. S. commune had a significant growth-promoting effect on blueberry tissue-cultured seedlings. After inoculation with S. commune, inoculation with the pathogenic fungus, or inoculation at a later time, the strain significantly reduced the root rot disease index in the potted blueberry seedlings, with relative control effects of 79.14% and 62.57%, respectively. In addition, S. commune G18 significantly increased the antioxidant enzyme contents in the aboveground and underground parts of potted blueberry seedlings. We can conclude that S. commune is a potential biocontrol agent that can be used to effectively control blueberry root rot caused by F. commune in the field.


Assuntos
Mirtilos Azuis (Planta) , Fusarium , Doenças das Plantas , Raízes de Plantas , Schizophyllum , Mirtilos Azuis (Planta)/microbiologia , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Raízes de Plantas/microbiologia , Fusarium/fisiologia , Schizophyllum/metabolismo , Schizophyllum/crescimento & desenvolvimento , Antibiose , Hifas/crescimento & desenvolvimento , Agentes de Controle Biológico , Plântula/microbiologia , Plântula/crescimento & desenvolvimento
20.
Nat Commun ; 15(1): 3770, 2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38704366

RESUMO

Aspergillus fumigatus is the leading causative agent of life-threatening invasive aspergillosis in immunocompromised individuals. One antifungal class used to treat Aspergillus infections is the fungistatic echinocandins, semisynthetic drugs derived from naturally occurring fungal lipopeptides. By inhibiting beta-1,3-glucan synthesis, echinocandins cause both fungistatic stunting of hyphal growth and repeated fungicidal lysis of apical tip compartments. Here, we uncover an endogenous mechanism of echinocandin tolerance in A. fumigatus whereby the inducible oxylipin signal 5,8-diHODE confers protection against tip lysis via the transcription factor ZfpA. Treatment of A. fumigatus with echinocandins induces 5,8-diHODE synthesis by the fungal oxygenase PpoA in a ZfpA dependent manner resulting in a positive feedback loop. This protective 5,8-diHODE/ZfpA signaling relay is conserved among diverse isolates of A. fumigatus and in two other Aspergillus pathogens. Our findings reveal an oxylipin-directed growth program-possibly arisen through natural encounters with native echinocandin producing fungi-that enables echinocandin tolerance in pathogenic aspergilli.


Assuntos
Antifúngicos , Aspergilose , Aspergillus fumigatus , Equinocandinas , Proteínas Fúngicas , Oxilipinas , Antifúngicos/farmacologia , Equinocandinas/farmacologia , Aspergillus fumigatus/efeitos dos fármacos , Aspergillus fumigatus/metabolismo , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/antagonistas & inibidores , Oxilipinas/metabolismo , Oxilipinas/farmacologia , Aspergilose/tratamento farmacológico , Aspergilose/microbiologia , Transdução de Sinais/efeitos dos fármacos , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Hifas/efeitos dos fármacos , Hifas/crescimento & desenvolvimento , Hifas/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética
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