Analyses of gene expression regulation in a time-course experiment provided the first insights into the processes that were activated and those that were repressed during the Y-to-H transition in O. These analyses further confirmed the occurrence of major rearrangement of the cell wall and cellular structures. We pointed out both genes and pathways that are either specific to O.
Our experimental conditions also suggest the involvement of PKA and RIM pathways, which should be confirmed in future studies. Taken together, our results indicate many genes of interest for further investigations of the Y-to-H transition in O. Collections ChampignonsPathogenes were first grown in liquid minimum medium OMM [ 93 ] that was supplemented with 1. Cells were considered hyphal structures when they were at least twice as long as a typical yeast cell. About 60 structures were counted and measured at each time.
Pellets were resuspended in sterile water and transferred to 1. Three time series replicates were collected 18 samples in total. OMM that was supplemented with 1. Cells were grown and collected following the same procedure as for RNA extractions. Pellets of cells were resuspended in fixation buffer 2. Filtered reads were mapped onto the exon sequences of the O. For greater readability in the manuscript, genes of O. All further analyses were performed in the R statistical environment v3.
Raw data were filtered and transformed with the Bioconductor package EdgeR correction by the library size and filtering of genes for which the row sum was less than 3 counts per million [CPM] [ 98 ]. A multidimensional scaling MDS plot was used for the visualization of the variability among samples function implemented in EdgeR , following the procedure described previously [ 48 ]. The MDS plot was produced using the R package ggplot2 [ 99 ].
The software assigns genes to a set of model profiles predefined in order to capture all the potential distinct patterns that can be expected from the experiment [ 53 ]. We chose a maximum number of 50 for model profiles with a significance threshold of 0. A minimum fold change of two was required over time between normalized count values for a gene to be retained.
Differential expression for each gene was calculated on the normalized count values, as:. Values less than 0 were inverted to ease of interpretation; in this case, the equation was written as:. Gene ontology GO term enrichment analyses were performed as described in Nigg and collaborators using the Goseq package in Bioconductor 3. REVIGO was used to reduce redundancy and produce treemaps space-filling visualization of hierarchical structures using the treemap package in R [ 54 ].
Default parameters were used and the redundancy threshold allowed similarity was set at 0. Orthologous genes among the identified homologs were highlighted by reciprocal best blast hits RBH using tblastx [ ]. Exon sequences of the two species O. DNA fragments were visualized under UV light. Brasier CM. Ophiostoma novo-ulmi sp. Campana RJ. Inoculation and fungal invasion of the tree. Dutch elm Dis. Ithaca: Cornell Un; The transmission of Dutch elm disease: a study of the process involved. Invertebrate-microbial interactions. Cambridge: Cambridge University Press; Dogra N, Breuil C.
Suppressive subtractive hybridization and differential screening identified genes differentially expressed in yeast and mycelial forms of Ophiostoma piceae. Krokene P, Solheim H. Pathogenicity of four blue-stain fungi associated with aggressive and nonaggressive bark beetles. Syst Appl Microbiol. Naruzawa ES, Bernier L. Control of yeast-mycelium dimorphism in vitro in Dutch elm disease fungi by manipulation of specific external stimuli.
Fungal Biol. Nutritional control of dimorphism in Ceratocystis ulmi. Exp Mycol. Can J Bot. Effect of linoleic acid on reproduction and yeast-mycelium dimorphism in the Dutch elm disease pathogens. Calmodulin levels in the yeast and mycelial phases of Ceratocystis ulmi. J Bacteriol. Muthukumar G, Nickerson KW. Ca II -calmodulin regulation of fungal dimorphism in Ceratocystis ulmi.
Inoculum size effect in dimorphic fungi: extracellular control of yeast-mycelium dimorphism in Ceratocystis ulmi. Appl Environ Microbiol. Quorum sensing activity in Ophiostoma ulmi : effects of fusel oils and branched chain amino acids on yeast-mycelial dimorphism. J Appl Microbiol. Diversity in yeast—mycelium dimorphism response of the Dutch elm disease pathogens: the inoculum size effect. Can J Microbiol. Quorum sensing activity and control of yeast-mycelium dimorphism in Ophiostoma floccosum.
Biotechnol Lett. Quorum sensing mechanisms mediated by farnesol in Ophiostoma piceae : its effect on the secretion of sterol esterase. A gene associated with filamentous growth in Ophiostoma novo-ulmi has RNA-binding motifs and is similar to a yeast gene involved in mRNA splicing. Curr Genet. An abnormal strain of Ceratocystis ulmi incapable of producing external symptoms of Dutch elm disease. Eur J For Pathol. Richards WC. Nonsporulation in the Dutch elm disease fungus Ophiostoma ulmi : evidence for control by a single nuclear gene.
Rev Can Bot. Gancedo JM. Control of pseudohyphae formation in Saccharomyces cerevisiae. Dimorphism in fungal pathogens: Candida albicans and Ustilago maydis — similar inputs, different outputs.
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Curr Opin Microbiol. Dimorphism in fungal plant pathogens. MAP kinase and cAMP signaling pathways modulate the pH-induced yeast-to-mycelium dimorphic transition in the corn smut fungus Ustilago maydis. Curr Microbiol. Ustilago maydis phosphodiesterases play a role in the dimorphic switch and in pathogenicity. Mol Microbiol. Selvig K, Alspaugh JA. Ambient pH gene regulation in fungi: making connections. Trends Microbiol. The control of filamentous differentiation and virulence in fungi. Trends Cell Biol. Mitogen-activated protein kinase signaling in plant-interacting fungi: distinct messages from conserved messengers.
Plant Cell. EMBO J. Genetic networks inducing invasive growth in Saccharomyces cerevisiae identified through systematic genome-wide overexpression. Role of the mitogen-activated protein kinase Hog1p in morphogenesis and virulence of Candida albicans. Signal transduction cascades regulating fungal development and virulence. Microbiol Mol Biol Rev. Pan X, Heitman J. Cyclic AMP-dependent protein kinase regulates pseudohyphal differentiation in Saccharomyces cerevisiae.
Mol Cell Biol. The three yeast A kinases have specific signaling functions in pseudohyphal growth. The Yak1 protein kinase lies at the center of a regulatory cascade affecting adhesive growth and stress resistance in Saccharomyces cerevisiae. Nonfilamentous C. Davis D. Adaptation to environmental pH in Candida albicans and its relation to pathogenesis.
Regulation of gene expression by ambient pH in filamentous fungi and yeasts. Signature gene expression reveals novel clues to the molecular mechanisms of dimorphic transition in Penicillium marneffei. PLoS Genet. Transcription profiling of Candida albicans cells undergoing the yeast-to-hyphal transition. Mol Biol Cell. Kadosh D, Johnson A.
Induction of the Candida albicans filamentous growth program by relief of transcriptional repression: a genome-wide analysis. Carlisle PL, Kadosh D. A genome-wide transcriptional analysis of morphology determination in Candida albicans. J Biomol Tech. Functional annotation of the Ophiostoma novo-ulmi genome: insights into the phytopathogenicity of the fungal agent of Dutch elm disease.
Genome Biol Evol. RNAseq analysis highlights specific transcriptome signatures of yeast and mycelial growth phases in the Dutch elm disease fungus Ophiostoma novo-ulmi. Benjamini Y, Hochberg Y. Controlling the false discovery rate: a practical and powerful approach to multiple testing. J R Statistical Soc. Ernst J, Bar-Joseph Z. STEM: a tool for the analysis of short time series gene expression data. BMC Bioinformatics. Clustering short time series gene expression data. PLoS One. Hypoxia and temperature regulated morphogenesis in Candida albicans.
Large-scale analysis of yeast filamentous growth by systematic gene disruption and overexpression. Functional categorization of unique expressed sequence tags obtained from the yeast-like growth phase of the elm pathogen Ophiostoma novo-ulmi.
BMC Genomics. Morphogenesis in the yeast cell cycle: regulation by Cdc28 and cyclins. J Cell Biol. Wang Y. CDKs and the yeast-hyphal decision. Moseley JB, Nurse P. Cdk1 and cell morphology: connections and directions. Curr Opin Cell Biol. Woronin M. Zur Entwicklungsgeschichte der Ascobolus pulcherrimus Cr. Multiperforate septations, woronin bodies, and septal plugs in Fusarium. Cell Biol. Comparative transcriptomics of the saprobic and parasitic growth phases in Coccidioides spp.
Jedd G, Chua NH. A new self-assembled peroxisomal vesicle required for efficient resealing of the plasma membrane. Nat Cell Biol. Hex-1, a gene unique to filamentous fungi, encodes the major protein of the Woronin body and functions as a plug for septal pores. Fungal Genet Biol. Beck J, Ebel F. Characterization of the major Woronin body protein HexA of the human pathogenic mold Aspergillus fumigatus. The results showed that the root pathogenic and mycoparasitic fungi tested were more sensitive to chitosan than nematophagous and entomopathogenic fungi.
Chitosanases and perhaps related enzymes are involved in the resistance to chitosan. Two fungi , one sensitive to chitosan, Fusarium oxysporum f. Transmission electron microscopy revealed differences in the ultrastructural alterations caused by chitosan in the spores of the plant pathogenic fungus and in those of the nematophagous fungus.
Confocal laser microscopy showed that Rhodamine-labelled chitosan enters rapidly into conidia of both fungi , in an energy-dependent process. Nematophagous and entomopathogenic fungi are rather resistant to the toxic effect of chitosan. Resistance of nematophagous and entomopathogenic fungi to chitosan could be associated with their high extracellular chitosanolytic activity.
Furthermore, ultrastructural damage is much more severe in the chitosan sensitive fungus. The results of this paper suggest that biocontrol fungi tested could be combined with chitosan for biological control of plant pathogens and pests. Pathogenicity of Three Entomopathogenic Fungi to Matsucoccus matsumurae. Matsucoccus matsumurae Kuwana Hemiptera: Coccoidea: Matsucoccidae is an invasive alien species and a destructive pest of two native Chinese pines, Pinus tabulaeformis Carr. The pathogenicity of three entomopathogenic fungi , Lecanicillium lecanii strain V3. The results showed that the four strains caused disease and death of the scale insect, among which the L.
Furthermore, L. The adult females and the male 3rd-instar nymphs of M. The body surface structure, cuticle thickness and wax secretions of M. Pathogenicity of three entomopathogenic fungi to Matsucoccus matsumurae. This research is concerned with the fungicidal properties of nano-size silver colloidal solution used as an agent for antifungal treatment of various plant pathogens.
Eighteen different plant pathogenic fungi were treated with these AgNPs on potato dextrose agar PDA , malt extract agar, and corn meal agar plates. We calculated fungal inhibition in order to evaluate the antifungal efficacy of silver nanoparticles against pathogens. The results indicated that AgNPs possess antifungal properties against these plant pathogens at various levels. Results also showed that the most significant inhibition of plant pathogenic fungi was observed on PDA and ppm of AgNPs.
Production of cross-kingdom oxylipins by pathogenic fungi : An update on their role in development and pathogenicity. Oxylipins are a class of molecules derived from the incorporation of oxygen into polyunsaturated fatty acid substrates through the action of oxygenases. While extensively investigated in the context of mammalian immune responses, over the last decade it has become apparent that oxylipins are a common means of communication among and between plants, animals, and fungi to control development and alter host-microbe interactions.
In fungi , some oxylipins are derived nonenzymatically while others are produced by lipoxygenases, cyclooxygenases, and monooxygenases with homology to plant and human enzymes. Recent investigations of numerous plant and human fungal pathogens have revealed oxylipins to be involved in the establishment and progression of disease.
In fungi , some oxylipins are derived non-enzymatically while others are produced by lipoxygenases, cyclooxygenases, and monooxygenases with homology to plant and human enzymes. Swainsonine biosynthesis genes in diverse symbiotic and pathogenic fungi. Swainsonine, a cytotoxic fungal alkaloid and a potential cancer therapy drug, is produced by the insect pathogen and plant symbiont, Metarhizium robertsii, the clover pathogen Slafractonia leguminicola, locoweed symbionts belonging to Alternaria sect.
Undifilum, and a recently discovered morning glo Plants are able to interact with their environment by emitting volatile organic compounds. We investigated the volatile interactions that take place below ground between barley roots and two pathogenic fungi , Cochliobolus sativus and Fusarium culmorum.
The volatile molecules emitted by each fungus, by non-infected barley roots and by barley roots infected with one of the fungi or the two of them were extracted by head-space solid phase micro extraction and analyzed by gas chromatography mass spectrometry. The effect of fungal volatiles on barley growth and the effect of barley root volatiles on fungal growth were assessed by cultivating both organisms in a shared atmosphere without any physical contact. The results show that volatile organic compounds, especially terpenes, are newly emitted during the interaction between fungi and barley roots.
The volatile molecules released by non-infected barley roots did not significantly affect fungal growth, whereas the volatile molecules released by pathogenic fungi decreased the length of barley roots by 19 to The spectrum of the volatiles released by infected barley roots had no significant effect on F. This paper identifies the volatile organic compounds emitted by two pathogenic fungi and shows that pathogenic fungi can modify volatile emission by infected plants.
Our results open promising perspectives concerning the biological control of edaphic diseases. Amoeba provide insight into the origin of virulence in pathogenic fungi. Why are some fungi pathogenic while the majority poses no threat to humans or other hosts? Of the more than 1. In contrast, fungi are major pathogens for plants and insects. These facts pose several fundamental questions including the mechanisms responsible for the origin of virulence among the few pathogenic species and the high resistance of mammals to fungal diseases. This essay explores the origin of virulences among environmental fungi with no obvious requirement for animal association and proposes that selection pressures by amoeboid predators led to the emergence of traits that can also promote survival in mammalian hosts.
In this regard, analysis of the interactions between the human pathogenic funges Cryptococcus neoformans and amoeba have shown a remarkable similarity with the interaction of this fungus with macrophages. Hence the virulence of environmental pathogenic fungi is proposed to originate from a combination of selection by amoeboid predators and perhaps other soil organism with thermal tolerance sufficient to allow survival in mammalian hosts.
Kujoth, Gregory C. ABSTRACT Blastomyces dermatitidis is a human fungal pathogen of the lung that can lead to disseminated disease in healthy and immunocompromised individuals. Genetic analysis of this fungus is hampered by the relative inefficiency of traditional recombination-based gene-targeting approaches. We created targeting plasmid vectors expressing Cas9 and either one or two single guide RNAs and introduced these plasmids into Blastomyces via Agrobacterium gene transfer. We succeeded in disrupting several fungal genes, including PRA1 and ZRT1, which are involved in scavenging and uptake of zinc from the extracellular environment.
Simultaneous dual-gene targeting proceeded with efficiencies similar to those of single-gene-targeting frequencies for the respective targets. Analysis of species diversity of the micro- fungi typically detected at the sites of biodamage of synthetic polymers on space vehicles exhibited the presence of a broad variety of opportunistic pathogens and toxic species.
Thus, 78 species of micromycetes of polymer destructing fungi are associated with biological risk levels BSL-1 and BSL-2 low and moderate levels, respectively. As many as 56 species are able to produce toxic compounds. Contribution to the knowledge of pathogenic fungi of spiders in Argentina. Southernmost record in the world.
The aim of this study was to identify entomopathogenic fungi infecting spiders Araneae in a protected area of Buenos Aires province, Argentina. The Araneae species identified was Stenoterommata platensis. This study constitutes the southernmost records in the world and contributes to expanding the knowledge of the biodiversity of pathogenic fungi of spiders in Argentina. Common bean Phaseolus vulgaris L. In Nicaragua, certified healthy seeds of local bean varieties are not available, and seedborne fungi have gained little attention.
A total of fungal strains were isolated from surface-sterilized beans and inoculated to healthy lima beans Phaseolus lunatus under controlled conditions. Eighty-seven isolates caused symptoms of varying severity in the seedlings, including discoloration, necrotic lesions, cankers, rot, and lethal necrosis. Pathogenic isolates were divided into eight phenotypically distinguishable groups based on morphology and growth characteristics on artificial growth medium, and further identified by analysis of the internal transcribed spacer sequences ITS1 and ITS2 of the ribosomal RNA genes.
The pathogenic isolates belonged to eight genera. Fusarium spp. Furthermore, Corynespora cassiicola, Colletotrichum capsisi, Colletotrichum gloeosporioides, Aspergillus flavus, and Diaporthe sp. This study reveals, for the first time, many seedborne pathogenic fungi in beans in Nicaragua; furthermore, prior to this study, little information was available concerning F. Our results lay the basis for developing diagnostic tools for seed health inspection and for further study of the epidemiology.
Multiple rare opportunistic and pathogenic fungi in persistent foot skin infection. Persistent superficial skin infection caused by multiple fungi is rarely reported. Recently, a number of fungi , both opportunistic and persistent in nature were isolated from the foot skin of a year old male in Malaysia. The fungi were identified as Candida parapsilosis, Rhodotorula mucilaginosa, Phoma spp. Among the isolated fungi , C. Interestingly, it was noted that C. This discovery will shed light on future research to explore on effective treatment for inhibition of pathogenic halophiles as well as to understand the interaction of multiple fungi in the progress of skin infection.
Synthesis and in vitro antifungal efficacy of oleoyl-chitosan nanoparticles against plant pathogenic fungi. An antifungal dispersion system was prepared by oleoyl-chitosan O-chitosan nanoparticles, and the antifungal activity against several plant pathogenic fungi was investigated. Under scanning electron microscopy, the nanoparticles formulation appeared to be uniform with almost spherical shape.
The particle size of nanoparticles was around Transmission electron microscopy observation showed that nanoparticles could be well distributed in potato dextrose agar medium. Mycelium growth experiment demonstrated that Nigrospora sphaerica, Botryosphaeria dothidea, Nigrospora oryzae and Alternaria tenuissima were chitosan-sensitive, while Gibberella zeae and Fusarium culmorum were chitosan-resistant. The antifungal index was increased as the concentration of nanoparticles increased for chitosan-sensitive fungi.
Fatty acid analyses revealed that plasma membranes of chitosan-sensitive fungi were shown to have lower levels of unsaturated fatty acid than chitosan-resistant fungi. Phylogenetic analysis based on ITS gene sequences indicated that two chitosan-resistant fungi had a near phylogenetic relationship. Results showed that O-chitosan nanoparticles could be a useful alternative for controlling pathogenic fungi in agriculture.
The isolation and identification of pathogenic fungi from Tessaratoma papillosa Drury Hemiptera: Tessaratomidae. Litchi stink-bug, Tessaratoma papillosa Drury Hemiptera: Tessaratomidae , is one of the most widespread and destructive pest species on Litchi chinensis Sonn and Dimocarpus longan Lour in Southern China. Inappropriate use of chemical pesticides has resulted in serious environmental problems and food pollution. Generating an improved Integrated Pest Management IPM strategy for litchi stink-bug in orchard farming requires development of an effective biological control agent.
Entomopathogenic fungi are regarded as a vital ecological factor in the suppression of pest populations under field conditions. With few effective fungi and pathogenic strains available to control litchi stink-bug, exploration of natural resources for promising entomopathogenic fungi is warranted. In this study, two pathogenic fungi were isolated from cadavers of adult T. Infection of T. Biological tests showed that the two entomopathogenic fungi induced high mortality in 2 nd and 5 th instar nymphs of T.
This study provides two valuable entomopathogenic fungi from T. This finding suggests that the highly virulent P. These pathogenic fungi had no pollution or residue risk, and could provide an alternative option for IPM of litchi stink-bug. Human pathogenic bacteria, fungi , and viruses in Drosophila. Drosophila has been the invertebrate model organism of choice for the study of innate immune responses during the past few decades. Many Drosophila—microbe interaction studies have helped to define innate immunity pathways, and significant effort has been made lately to decipher mechanisms of microbial pathogenesis.
Here we catalog 68 bacterial, fungal, and viral species studied in flies, 43 of which are relevant to human health. We discuss studies of human pathogens in flies revealing not only the elicitation and avoidance of immune response but also mechanisms of tolerance, host tissue homeostasis, regeneration, and predisposition to cancer.
Prominent among those is the emerging pattern of intestinal regeneration as a defense response induced by pathogenic and innocuous bacteria. Immunopathology mechanisms and many microbial virulence factors have been elucidated, but their relevance to human health conventionally necessitates validation in mammalian models of infection.
Genomes, free radicals and plant cell invasion: recent developments in plant pathogenic fungi. This review describes current advances in our understanding of fungal-plant interactions. The widespread application of whole genome sequencing to a diverse range of fungal species has allowed new insight into the evolution of fungal pathogenesis and the definition of the gene inventories associated with important plant pathogens.
This has also led to functional genomic approaches to carry out large-scale gene functional analysis. There has also been significant progress in understanding appressorium-mediated plant infection by fungi and its underlying genetic basis. The nature of biotrophic proliferation of fungal pathogens in host tissue has recently revealed new potential mechanisms for cell-to-cell movement by invading pathogens. The results showed that the active products of Ag-antibiotic had stronger inhibition effect on 13 test pathogens , among which, Sclerotinia sclerotiorum was most sensitive, with the EC50 being 0.
As compared with the control, the relative electric conductivity of R. The cell membrane outline was not clear, organelles were badly damaged, and vacuole appeared. It was suggested that the inhibition of ergosterol biosynthesis and the increase of membrane permeability could be the main action mechanisms of Ag-antibiotic against pathogenic fungi. Signal transduction pathways regulating growth and stress responses are areas of significant study in the effort to delineate pathogenic mechanisms of fungi.
In-depth knowledge of signal transduction events deepens our understanding of how a fungal pathogen is able to sense changes in the environment and respond accordingly by modulation of gene expression and re-organization of cellular activities to optimize fitness. Members of the Ras protein family are important regulators of growth and differentiation in eukaryotic organisms, and have been the focus of numerous studies exploring fungal pathogenesis. Here, the current data regarding Ras signal transduction are reviewed for three major pathogenic fungi : Cryptococcus neoformans, Candida albicans and Aspergillus fumigatus.
Particular emphasis is placed on Ras-protein interactions during control of morphogenesis, stress response and virulence. Making a protein extract from plant pathogenic fungi for gel- and LC-based proteomics. Proteomic technologies have become a successful tool to provide relevant information on fungal biology. In the case of plant pathogenic fungi , this approach would allow a deeper knowledge of the interaction and the biological cycle of the pathogen , as well as the identification of pathogenicity and virulence factors. These two elements open up new possibilities for crop disease diagnosis and environment-friendly crop protection.
Phytopathogenic fungi , due to its particular cellular characteristics, can be considered as a recalcitrant biological material, which makes it difficult to obtain quality protein samples for proteomic analysis. This chapter focuses on protein extraction for gel- and LC-based proteomics with specific protocols of our current research with Botrytis cinerea. Summary Despite continuous contact with fungi , immunocompetent individuals rarely develop pro-inflammatory antifungal immune responses.
The underlying tolerogenic mechanisms are incompletely understood.
Glycoconjugates and polysaccharides of fungal cell wall and activation of immune system
Using both mouse models and human patients, we show that infection with the human pathogenic fungi Aspergillus fumigatus and Candida albicans induces a distinct subset of neutrophilic myeloid-derived suppressor cells MDSCs , which functionally suppress T and NK cell responses. Fungal MDSC induction is further dependent on pathways downstream of Dectin-1 signaling, notably reactive oxygen species ROS generation as well as caspase-8 activity and interleukin-1 IL-1 production.
These studies define an innate immune mechanism by which pathogenic fungi regulate host defense. To identify the causative fungi of fungal keratitis, test their susceptibility to antifungal agents with the disk diffusion method and study the relationship between the organisms, the inhibition zones and the clinical outcomes. Pathogenic fungi were isolated by corneal scraping, identified by fungal cultivation and subjected to drug sensitivity tests conducted with the disk diffusion method.
The patients were treated initially with voriconazole, terbinafine and natamycin eye drops for one week. Further treatment continued using the most effective drug according to the drug sensitivity results. The patients were followed up every week until three months after cured. The inhibition zones of fungi cultured with voriconazole, terbinafine and natamycin were compared.
The relationship between inhibition zones and organism, organism and treatment results measure, and each treatment results measure and inhibition zones were evaluated. Of patients, Keratitis patients infected with Aspergillus keratitis had the worst outcome. The size of the inhibition zones of Aspergillus spp. Aspergillus and Fusarium were the predominant pathogenic genera causing fungal keratitis in our patients. Among the causative fungi , infections due to Aspergillus spp.
The inhibition zones of fungal isolates in response to natamycin significantly correlated with the treatment outcomes of keratitis. Specifically, the smaller the natamycin inhibition zone, the lower the. Diseases caused by fungi can occur in healthy people, but immunocompromised patients are the major risk group for invasive fungal infections. Cases of fungal resistance and the difficulty of treatment make fungal infections a public health problem.
This review explores mechanisms used by fungi to promote fungal resistance, such as the mutation or overexpression of drug targets, efflux and degradation systems, and pleiotropic drug responses. Alternative novel drug targets have been investigated; these include metabolic routes used by fungi during infection, such as trehalose and amino acid metabolism and mitochondrial proteins. An overview of new antifungal agents, including nanostructured antifungals, as well as of repositioning approaches is discussed.
Studies focusing on the development of vaccines against antifungal diseases have increased in recent years, as these strategies can be applied in combination with antifungal therapy to prevent posttreatment sequelae. Studies focused on the development of a pan-fungal vaccine and antifungal drugs can improve the treatment of immunocompromised patients and reduce treatment costs.
Fungi that Infect Humans. Fungi must meet four criteria to infect humans: growth at human body temperatures, circumvention or penetration of surface barriers, lysis and absorption of tissue, and resistance to immune defenses, including elevated body temperatures. Morphogenesis between small round, detachable cells and long, connected cells is the mechanism by which fungi solve problems of locomotion around or through host barriers.
Secretion of lytic enzymes, and uptake systems for the released nutrients, are necessary if a fungus is to nutritionally utilize human tissue. Last, the potent human immune system evolved in the interaction with potential fungal pathogens , so few fungi meet all four conditions for a healthy human host. Paradoxically, the advances of modern medicine have made millions of people newly susceptible to fungal infections by disrupting immune defenses. This article explores how different members of four fungal phyla use different strategies to fulfill the four criteria to infect humans: the Entomophthorales, the Mucorales, the Ascomycota, and the Basidiomycota.
Unique traits confer human pathogenic potential on various important members of these phyla: pathogenic Onygenales comprising thermal dimorphs such as Histoplasma and Coccidioides ; the Cryptococcus spp. Also discussed are agents of neglected tropical diseases important in global health such as mycetoma and paracoccidiomycosis and common pathogens rarely implicated in serious illness such as dermatophytes.
Commensalism is considered, as well as parasitism, in shaping genomes and physiological systems of hosts and fungi during evolution. Morphological characteristics and pathogenicity of fungi associated with Roselle Hibiscus Sabdariffa diseases in Penang, Malaysia. Roselle, or Jamaica sorrel Hibiscus sabdariffa is a popular vegetable in many tropical regions, cultivated for its leaves, seeds, stems and calyces which, the dried calyces are used to prepare tea, syrup, jams and jellies and as beverages.
The main objectives of this study were to identify and characterise fungal pathogens associated with Roselle diseases based on their morphological and cultural characteristics and to determine the pathogenicity of four fungi infecting Roselle seedlings, namely Phoma exigua, Fusarium nygamai, Fusarium tgcq and Rhizoctonia solani in Penang. A total of fungal isolates were obtained from 90 samples of symptomatic Roselle tissues. The isolates were identified based on cultural and morphological characteristics, as well as their pathogenicity.
The fungal pathogen most frequently isolated was P. Pathogenicity tests showed that P. Fungi in healthy and diseased sea fans Gorgonia ventalina : is Aspergillus sydowii always the pathogen? Caribbean corals, including sea fans Gorgonia spp. In the case of sea fans, the pathogen is reported to be the fungus Aspergillus sydowii, and the disease is named aspergillosis. In order to understand coral diseases and pathogens , knowledge of the microbes associated with healthy corals is also necessary.
In this study the fungal community of healthy Gorgonia ventalina colonies was contrasted with that of diseased colonies. In addition, the fungal community of healthy and diseased tissue within colonies with aspergillosis was contrasted. Fungi were isolated from healthy and diseased fans from 15 reefs around Puerto Rico, and identified by sequencing the nuclear ribosomal ITS region and by morphology.
Thirty fungal species belonging to 15 genera were isolated from G. Penicillum and Aspergillus were the most common genera isolated from both healthy and diseased fans. However, the fungal community of healthy fans was distinct and more diverse than that of diseased ones.
Within diseased fans, fungal communities from diseased tissues were distinct and more diverse than from healthy tissue. The reduction of fungi in diseased colonies may occur prior to infection due to environmental changes affecting the host, or after infection due to increase in dominance of the pathogen , or because of host responses to infection. Data also indicate that the fungal community of an entire sea fan colony is affected even when only a small portion of the colony suffers from aspergillosis.
An unexpected result was that A. This result suggests that A. Given that it is not clear that Aspergillus is the sole pathogen , calling this disease aspergillosis is an. Nontuberculous mycobacteria, fungi , and opportunistic pathogens in unchlorinated drinking water in The Netherlands. The multiplication of opportunistic pathogens in drinking water supplies might pose a threat to public health.
In this study, distributed unchlorinated drinking water from eight treatment plants in the Netherlands was sampled and analyzed for fungi , nontuberculous mycobacteria NTM , and several opportunistic pathogens by using selective quantitative PCR methods. Fungi and NTM were detected in all drinking water samples, whereas Legionella pneumophila, Pseudomonas aeruginosa, Stenotrophomonas maltophilia, and Aspergillus fumigatus were sporadically observed.
Mycobacterium avium complex and Acanthamoeba spp. Season had no influence on the occurrence of these organisms, except for NTM and S. Opportunistic pathogens were more often observed in premise plumbing water samples than in samples from the distribution system. The lowest number of these organisms was observed in the finished water at the plant. Thus, fungi , NTM, and some of the studied opportunistic pathogens can multiply in the distribution and premise plumbing systems. However, L. Finally, samples that contained L. Isolation and characterization of antagonistic fungi against potato scab pathogens from potato field soils.
Potato scab is a serious plant disease caused by several Streptomyces sp. Although antagonistic bacteria and phages against potato scab pathogens have been reported, to the best of our knowledge, there is no information about fungi that are antagonistic to the pathogens. The aim of this study was to isolate fungal antagonists, characterize their phylogenetic positions, determine their antagonistic activities against potato scab pathogens , and highlight their potential use as control agents under lower pH conditions.
Fifteen fungal stains isolated from potato field soils were found to have antagonistic activity against three well-known potato scab pathogens : Streptomyces scabiei, Streptomyces acidiscabiei, and Streptomyces turgidiscabiei. These 15 fungal strains were phylogenetically classified into at least six orders and nine genera based on 18S rRNA gene sequencing analysis. These fungal isolates were related to members of the genera Penicillium, Eupenicillium, Chaetomium, Fusarium, Cladosporium, Mortierella, Kionochaeta, Pseudogymnoascus, and Lecythophora.
The antagonistic activities of most of the fungal isolates were highly strengthened under the lower pH conditions, suggesting the advantage of combining their use with a traditional method such as soil acidification. This is the first report to demonstrate that phylogenetically diverse fungi show antagonistic activity against major potato scab pathogens. These fungal strains could be used as potential agents to control potato scab disease. Isolation of fungi from dead arthropods and identification of a new mosquito natural pathogen.
Insects are well known vectors of human and animal pathogens and millions of people are killed by mosquito-borne diseases every year. The use of insecticides to target insect vectors has been hampered by the issues of toxicity to the environment and by the selection of resistant insects. Therefore, biocontrol strategies based on naturally occurring microbial pathogens emerged as a promising control alternative.
The entomopathogenic fungus Beauveria bassiana is well characterized and have been approved by the United States Environmental Protection Agency as a pest biological control method.
However, thousands of other fungi are unexploited and it is important to identify and use different fungi for biocontrol with possibly some vector specific strains. The aim of this study was to identify new fungal entomopathogens that may be used as potential mosquito biocontrol agents. Cadavers of arthropods were collected from pesticide free areas and the fungi associated isolated, cultured and identified. Then the ability of each isolate to kill laboratory insects was assayed and compared to that of B. In total we have isolated and identified 42 fungal strains from 17 different arthropod cadavers.
Twenty four fungal isolates were cultivated in the laboratory and were able to induce sporulation. When fungal spores were microinjected into Drosophila melanogaster, eight isolates proved to be highly pathogenic while the remaining strains showed moderate or no pathogenicity.
Then a selection of isolates was tested against Aedes mosquitoes in a model mimicking natural infections. Only one fungus Aspergillus nomius was as pathogenic as B.
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The obtained results are encouraging and demonstrate the feasibility of this simple approach for the identification of new potential mosquito killers. Indeed, it is essential to anticipate and prepare biocontrol methods to fight the expansion of mosquitoes' habitat predicted in certain. Small-molecule signaling is one major mode of communication within the polymicrobial consortium of soil and rhizosphere. While microbial secondary metabolite SM production and responses of individual species have been studied extensively, little is known about potentially conserved roles of SM signals in multilayered symbiotic or antagonistic relationships.
Here, we characterize the SM-mediated interaction between the plant- pathogenic bacterium Ralstonia solanacearum and the two plant- pathogenic fungi Fusarium fujikuroi and Botrytis cinerea We show that cellular differentiation and SM biosynthesis in F. In particular, fungal bikaverin production is induced and preferentially accumulates in fungal survival spores chlamydospores only when exposed to supernatants of ralsolamycin-producing strains of R.
Examining a strain of B. Our results suggest that conservation of microbial SM responses across distantly related fungi may arise from horizontal transfer of protective gene clusters that are activated by conserved regulatory cues, e. Occurrence of entomopathogenic fungi in tejocote Crataegus mexicana orchard soils and their pathogenicity against Rhagoletis pomonella. To determine the abundance and diversity of entomopathogenic fungi in tejocote orchard soils and evaluate their ability to infect Rhagoletis pomonella Walsh.
Surveys were made in two locations in Mexico state and two in Puebla state. Soil from selected locations was baited for entomopathogenic fungi with Galleria mellonella L. Pathogenicity of five selected B. Pupae were not susceptible; however, adults emerging from inoculated pupae did die due to infection. At least three species of entomopathogenic fungi are present in the soil from tejocote orchards, with B. Rhagoletis pomonella larvae were more susceptible to infection than pupae.
Our study has produced new information about the distribution of entomopathogenic fungi in cultivated soils from this region of North America, contributing to a better understanding of their natural occurrence and underpinning the development of biological control approaches.
For decades, fungi have been the main source for the discovery of novel antimicrobial drugs. The production of these metabolites is presumably epigenetically silenced under standard laboratory conditions. In this study, we investigated the effect of six small mass chemicals, of which some are known to act as epigenetic modulators, on the production of antimicrobial compounds in 54 spore forming fungi. The antimicrobial effect of fungal samples was tested against clinically facultative pathogens and multiresistant clinical isolates.
In total, 30 samples of treated fungi belonging to six different genera reduced significantly growth of different test organisms compared to the untreated fungal sample growth log reduction 0. For instance, the pellet of Penicillium restrictum grown in the presence of butyrate revealed significant higher antimicrobial activity against Staphylococcus S. Our study shows that every presumable fungus, even well described fungi , has the potential to produce novel antimicrobial compounds and that our approach is capable of rapidly filling the pipeline for yet undiscovered antimicrobial substances.
Fungi treated with small chemicals exhibit increased antimicrobial activity against facultative bacterial and yeast pathogens. Recent sequencing efforts revealed a still high number of so far unknown "cryptic" secondary metabolites. In vitro antifungal activity of three geophytic plant extracts against three post-harvest pathogenic fungi. Plant extracts appear to be one of the most effective alternative methods of plant diseases control which are less harmful to human beings and environment.
In vitro antifungal activity of methanolic extracts of three promising wild geophytic plants against three post-harvest pathogenic fungi using radial growth technique was conducted. These extracts included the shoot system S and underground parts R of Asparagus stipularis, Cyperus capitatus and Stipagrostis lanata. Cell wall fractionation Yeast cells from cultures that were 4 days old were collected by centrifugation as described above. Cell wall sugar composition Yeast cells were harvested, washed once with deionized water and disrupted in a Braun homogenizer for 5 min, alternating 1 min periods of shaking and 2 min of cooling on ice.
Phagocytosis assay Human monocyte-derived macrophages hMacs were obtained according to previous reports [ 30 , 31 ]. Ethics statement Venous blood was collected from the cubital veins of healthy adult volunteers, and all volunteers were informed of the study before providing written consent. Statistical analysis The sugar analysis and the uptake of S. Results Cell wall assembly of S. Download: PPT. Fig 1. Fig 2. Table 1. Inner layer cell wall thickness of Sporothrix spp.
Table 2. Cell wall polysaccharide and amino acid content of S.
Table 3. Cell wall carbohydrate content in Sporothrix spp. Fig 3. Flow cytometry analysis of S. Fig 4. Fig 5. Fluorescence microscopy of Sporothrix spp. Fig 6. Fluorescence microscopy of S. Polysaccharide structure of S. Fig 7. Infrared spectroscopy of the alkali-insoluble cell wall fraction of S.
Fig 8. Table 4. Glycogen alpha-particles are found near the plasma membrane and cell wall of Sporothrix sp. Fig 9. Interaction of S. Fig Panel illustrating the uptake of Sporothrix spp. Uptake by human monocyte-derived macrophages hMac of S. Discussion Cell wall glycoconjugates of pathogenic fungi are involved in virulence and pathogenicity and can modulate the innate immune response [ 21 , 22 , 40 ].
A new hypothetical cell wall model for the dimorphic pathogenic fungi S. Supporting information. S1 Fig. S2 Fig. S3 Fig. Presence of rosette-like glycogen alpha-particles surrounding the plasma membrane of Sporothrix spp. Acknowledgments The authors are grateful to Gillian Milne, Kevin Mackenzie and Lucy Wight for their help and technical skill during the electron microscopy and confocal microscopy experiments.
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Related Dimorphic Fungi: Their importance as Models for Differentiation and Fungal Pathogenesis
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