scholarly journals Hygiene Defense Behaviors Used by a Fungus-Growing Ant Depend on the Fungal Pathogen Stages

Insects ◽  
2019 ◽  
Vol 10 (5) ◽  
pp. 130 ◽  
Author(s):  
Ernesto Bonadies ◽  
William T. Wcislo ◽  
Dumas Gálvez ◽  
William O.H. Hughes ◽  
Hermógenes Fernández-Marín
Keyword(s):  
Fungal Pathogen ◽  
Fungal Pathogens ◽  
Animal Studies ◽  
Developmental Stages ◽  
Arms Race ◽  
Defensive Strategy ◽  
Defensive Behaviors ◽  
Metapleural Glands ◽  
Fungus Growing Ants ◽  
Parasite Challenge

Parasites and their hosts use different strategies to overcome the defenses of the other, often resulting in an evolutionary arms race. Limited animal studies have explored the differential responses of hosts when challenged by differential parasite loads and different developmental stages of a parasite. The fungus-growing ant Trachymyrmex sp. 10 employs three different hygienic strategies to control fungal pathogens: Grooming the antibiotic-producing metapleural glands (MGs) and planting or weeding their mutualistic fungal crop. By inoculating Trachymyrmex colonies with different parasite concentrations (Metarhizium) or stages (germinated conidia or ungermianted conidia of Metarhizium and Escovopsis), we tested whether ants modulate and change hygienic strategies depending on the nature of the parasite challenge. There was no effect of the concentration of parasite on the frequencies of the defensive behaviors, indicating that the ants did not change defensive strategy according to the level of threat. However, when challenged with conidia of Escovopsis sp. and Metarhizium brunneum that were germinated or not-germinated, the ants adjusted their thygienic behavior to fungal planting and MG grooming behaviors using strategies depending on the conidia germination status. Our study suggests that fungus-growing ants can adjust the use of hygienic strategies based on the nature of the parasites.

Nanoscale adhesion forces between the fungal pathogen Candida albicans and macrophages

2016 ◽  
Vol 1 (1) ◽  
pp. 69-74 ◽  
Author(s):  
Sofiane El-Kirat-Chatel ◽  
Yves F. Dufrêne
Keyword(s):  
Atomic Force Microscopy ◽  
Candida Albicans ◽  
Immune Cells ◽  
Fungal Pathogen ◽  
Fungal Pathogens ◽  
Adhesion Forces ◽  
Force Microscopy ◽  
Atomic Force

We establish atomic force microscopy as a new nanoscopy platform for quantifying the forces between fungal pathogens and immune cells.

scholarly journals Structural basis of Blastomyces Endoglucanase-2 adjuvancy in anti-fungal and -viral immunity

2021 ◽  
Vol 17 (3) ◽  
pp. e1009324
Author(s):  
Lucas dos Santos Dias ◽  
Hannah E. Dobson ◽  
Brock Kingstad Bakke ◽  
Gregory C. Kujoth ◽  
Junfeng Huang ◽  
...  
Keyword(s):  
Infectious Diseases ◽  
Influenza A ◽  
Fungal Pathogens ◽  
Animal Studies ◽  
Structural Basis ◽  
Viral Immunity ◽  
Mucosal Vaccination ◽  
Clinical Observations ◽  
Protective Antibodies ◽  
Anti Fungal

The development of safe subunit vaccines requires adjuvants that augment immunogenicity of non-replicating protein-based antigens. Current vaccines against infectious diseases preferentially induce protective antibodies driven by adjuvants such as alum. However, the contribution of antibody to host defense is limited for certain classes of infectious diseases such as fungi, whereas animal studies and clinical observations implicate cellular immunity as an essential component of the resolution of fungal pathogens. Here, we decipher the structural bases of a newly identified glycoprotein ligand of Dectin-2 with potent adjuvancy, Blastomyces endoglucanase-2 (Bl-Eng2). We also pinpoint the developmental steps of antigen-specific CD4+ and CD8+ T responses augmented by Bl-Eng2 including expansion, differentiation and tissue residency. Dectin-2 ligation led to successful systemic and mucosal vaccination against invasive fungal infection and Influenza A infection, respectively. O-linked glycans on Bl-Eng2 applied at the skin and respiratory mucosa greatly augment vaccine subunit- induced protective immunity against lethal influenza and fungal pulmonary challenge.

scholarly journals IDENTIFIKASI DAN UJI PATOGENISITAS CENDAWAN ENTOMOPATOGEN LOKAL TERHADAP Leptocorisa oratorius

EUGENIA ◽  
2011 ◽  
Vol 17 (3) ◽  
Author(s):  
Emmy Senewe ◽  
Guntur Manengkey
Keyword(s):  
Fungal Pathogen ◽  
Fungal Pathogens ◽  
Pathogenic Fungus ◽  
Pathogenic Fungi ◽  
North Sulawesi ◽  
Pathogenicity Tests ◽  
Major Pest ◽  
White Mycelium ◽  
Fusarium Sp ◽  
Leptocorisa Oratorius

ABSTRACT Leptocorisa oratorius is one major pest of rice in North Sulawesi. Hence, it is necessary to control the pest. The research objective was to identify and to test pathogenicity of local  entomopathogen fungi which infected  Leptocorisa oratorius. The pathogens were collected through sampling of L. oratorius which had been infected by the fungi in the field. The pathogenic fungi was isolated using PDA medium, identified followed by inoculation for pathogenecity test.  During several sampling pest, it was found that  L. oratorius was attacked by fungal pathogens in the field. The identification revelead that the fungal pathogens were Beauveria sp and Fusarium sp. Both the fungal pathogen produced white mycelium and could only be distinguished using microscope in the laboratory. Result of pathogenicity tests showed that the two fungal pathogens caused different mortality of the L. oratorius. Mortality of  L. oratorius caused by pathogenic fungus Beauveria sp was  30.3% . Whereas, mortality of  L. oratorius caused by Fusarium sp was only 3.33%. Keywords : pathogenic fungi, entomopathogen, pathogenicity tests, L. oratorius

Wheat TaLr35PR2 gene is required for Lr35-mediated adult plant resistance against leaf rust fungus

2020 ◽  
Vol 47 (1) ◽  
pp. 26
Author(s):  
Fang Liang ◽  
Xiong Du ◽  
Jiarui Zhang ◽  
Xiaoying Li ◽  
Fei Wang ◽  
...  
Keyword(s):  
Leaf Rust ◽  
Fungal Pathogens ◽  
Developmental Stages ◽  
Rust Fungus ◽  
Expression Patterns ◽  
Plant Defence ◽  
Adult Plant ◽  
Isogenic Line ◽  
Critical Function ◽  
Pathogenesis Related Protein

In this study we analysed the expression patterns of TaLr35PR2 and confirmed its role in Lr35-mediated adult resistance to leaf rust fungus. β-1,3-glucanase, a pathogenesis-related protein, has a critical function in plant defence response against fungal pathogens. We previously described the full-length gene TaLr35PR2, which encodes a protein exhibiting amino acid and structural similarity to β-1,3-glucanase, in the wheat near-isogenic line TcLr35 (GenBank accession number DQ294235.1). This work aimed to further assess TaLr35PR2 expression patterns and function in Lr35-mediated adult resistance to Puccinia triticina. Immunoblot was performed to demonstrate that TaLr35PR2 expression was triggered early by P. triticina, with expression levels markedly elevated in incompatible interaction compared with those in compatible one. Additionally, TaLr35PR2 accumulation steadily increased and overtly peaked after challenge with P. triticina through the various developmental stages of TcLr35 wheat, and remaining at similar levels after mock inoculation. Furthermore, TaLr35PR2 expression was significantly reduced in barley stripe mosaic virus (BSMV)-induced gene knockdown plants, in which pathological assessment revealed that TaLr35PR2-silenced plants was obviously susceptible to leaf rust fungus compared with wild-type TcLr35, indicating that Lr35-mediated resistance to leaf rust was diminished. These findings strongly suggest that TaLr35PR2 is involved in Lr35-mediated wheat defence against the leaf rust pathogen.

scholarly journals Biocontrol ofPhytophthora infestans, Fungal Pathogen of Seedling Damping Off Disease in Economic Plant Nursery

2012 ◽  
Vol 2012 ◽  
pp. 1-6 ◽  
Author(s):  
B. Loliam ◽  
T. Morinaga ◽  
S. Chaiyanan
Keyword(s):  
Fungal Pathogen ◽  
Fungal Pathogens ◽  
High Efficiency ◽  
Peat Moss ◽  
Economic Plant ◽  
Damping Off ◽  
Termite Mounds ◽  
Plant Nursery ◽  
Significant Difference ◽  
Infected Tomato

This research aims to control Seedling damping off disease in plants by using antagonistic actinomycetes against the causative fungi.Phytophthora infestanswas isolated from the infected tomato plant seedling obtained from an economic plant nursery in Amphoe Pak Chong, Nakhon Ratchasima Province, Thailand. The chitinolyticStreptomyces rubrolavendulaeS4, isolated from termite mounds at the grove of Amphoe Si-Sawat, Kanchanaburi Province, Thailand, was proven to be the most effective growth inhibition of fungal pathogens tested on potato dextrose agar. Tomato and chili seedlings that colonized with antagonisticS. rubrolavendulaeS4 were grown inP. infestansartificial inoculated peat moss. Percents of noninfested seedling in fungal contaminated peat moss were compared to the controls with uninoculated peat moss. InP. infestanscontaminated peat moss, the percents of survival of tomato and chili seedling were significantly increased () from 51.42 to 88.57 and 34.10 to 76.71 for theS. rubrolavendulaeS4 treatment, respectively. TheS. rubrolavendulaeS4 also showed high efficiency equivalent to fungicide, metalaxyl with no significant difference (). It was clearly demonstrated thatS. rubrolavendulaeS4 can prevent the tomato and chili seedling damping off disease in economic plant nurseries.

scholarly journals Sick plants in grassland communities: a growth-defense trade-off is the main driver of fungal pathogen abundance and impact

2019 ◽  
Author(s):  
Seraina L. Cappelli ◽  
Noémie A. Pichon ◽  
Anne Kempel ◽  
Eric Allan
Keyword(s):  
Fungal Infection ◽  
Biomass Production ◽  
Fungal Pathogen ◽  
Fungal Pathogens ◽  
Nitrogen Addition ◽  
Main Determinant ◽  
Trade Off ◽  
Main Driver ◽  
Dilution Effects ◽  
Plant Pathogen Interactions

ABSTRACTAboveground fungal pathogens can substantially reduce biomass production in grasslands. However, we lack a mechanistic understanding of the drivers of fungal infection and impact. Using a global change biodiversity experiment we show that the trade-off between plant growth and defense is the main determinant of fungal infection in grasslands. Nitrogen addition only indirectly increased infection via shifting plant communities towards more fast growing species. Plant diversity did not decrease infection, likely because the spillover of generalist pathogens or dominance of susceptible species counteracted dilution effects. There was also evidence that fungal pathogens reduced biomass more strongly in diverse communities. Further, fungicide altered plant-pathogen interactions beyond just removing pathogens, probably by removing certain fungi more efficiently than others. Our results show that fungal pathogens have large effects on plant functional composition and biomass production and highlight the importance of considering changes in pathogen community composition to understand their effects.

scholarly journals Characterization of extracellular vesicles produced by Aspergillus fumigatus protoplasts

2020 ◽  
Author(s):  
Juliana Rizzo ◽  
Thibault Chaze ◽  
Kildare Miranda ◽  
Robert W. Roberson ◽  
Olivier Gorgette ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Cell Wall ◽  
Aspergillus Fumigatus ◽  
Extracellular Vesicles ◽  
Fungal Pathogen ◽  
Fungal Pathogens ◽  
Sugar Metabolism ◽  
Biologically Active ◽  
Thick Cell Wall ◽  
A Cell

AbstractExtracellular vesicles (EVs) are outer membranous compartments produced by yeast and mycelial forms of several fungal species. One of the difficulties to perceive the role of EVs during the fungal life is the fact that an active secretion of these EVs has not been clearly demonstrated in situ due to the presence of a thick cell wall. One alternative to have a better access to these vesicles is to use protoplasts. This approach has been investigated here with Aspergillus fumigatus, one of the most common opportunistic fungal pathogens worldwide. Analysis of regenerating protoplasts by scanning electron microscopy and fluorescence microscopy indicated the occurrence of outer membrane projections in association with surface components and the release of particles with properties resembling those of fungal EVs. EVs in culture supernatants were characterized by transmission electron microscopy and nanoparticle tracking analysis. Proteomic and glycome analysis of EVs revealed the presence of a complex array of enzymes related to lipid / sugar metabolism, pathogenic processes, and cell wall biosynthesis. Our data indicate that i) EV production is a common feature of different morphological stages of this major fungal pathogen, and ii) protoplastic EVs are a promising tool to undertake studies of vesicle functions in fungal cells.IMPORTANCEFungal cells use extracellular vesicles (EVs) to export biologically active molecules to the outer space. Since fungal cells are encaged in a thick cell wall, it is reasonable to expect that this structure might impact the vesicle-mediated molecular export. In this study, we used protoplasts of Aspergillus fumigatus, a major fungal pathogen, as a model to evaluate EV production in the absence of a cell wall. Our results demonstrated that wall-less A. fumigatus exports plasma membrane-derived EVs containing a complex combination of proteins and glycans. Our study is the first to characterize fungal EVs in the absence of a cell wall. Our results suggest that protoplasts are a promising model for functional studies of fungal vesicles.

scholarly journals Arabidopsis phytochelatin synthase 1, but not phytochelatin synthesis, functions in extracellular defense against multiple fungal pathogens

2019 ◽  
Author(s):  
Kian Hematy ◽  
Melisa Lim ◽  
Candice Cherk ◽  
Paweł Bednarek ◽  
Mariola Piślewska-Bednarek ◽  
...  
Keyword(s):  
Fungal Pathogen ◽  
Fungal Pathogens ◽  
Pathogenic Fungi ◽  
Plant Responses ◽  
Peptidase Activity ◽  
Phytochelatin Synthase ◽  
Biotic And Abiotic Stresses ◽  
Glutathione Conjugates ◽  
Heavy Metal Detoxification ◽  
Indole Glucosinolate

ABSTRACTPhytochelatin synthase (PCS) is a key component of heavy metal detoxification in plants. PCS catalyzes both the synthesis of the peptide phytochelatin from glutathione as well as the degradation of glutathione conjugates via peptidase activity. Here, we describe a hitherto uncharacterized role for PCS in disease resistance against plant pathogenic fungi. The pen4 mutant, which is allelic to cadmium insensitive 1 (cad1/pcs1) mutants, was recovered from a screen for Arabidopsis mutants with reduced resistance to the non-adapted barley fungal pathogen, Blumeria graminis f. sp. hordei. PCS1, which is found in the cytoplasm of cells of healthy plants, translocates upon pathogen attack and colocalizes with the PEN2 myrosinase on the surface of immobilized mitochondria. pcs1 and pen2 mutant plants exhibit a similar metabolic defect in the accumulation of pathogen-inducible indole glucosinolate-derived compounds, suggesting that PEN2 and PCS1 act in the same metabolic pathway. The function of PCS1 in this pathway is independent of phytochelatin synthesis and deglycination of glutathione conjugates, as catalytic-site mutants of PCS1 are still functional in indole glucosinolate metabolism. In uncovering a previously unknown function for PCS1, we reveal this enzyme to be a moonlighting protein important for plant responses to both biotic and abiotic stresses.

scholarly journals Rapid spatial learning controls instinctive defensive behavior in mice

2017 ◽  
Author(s):  
Ruben Vale ◽  
Dominic A. Evans ◽  
Tiago Branco
Keyword(s):  
Defensive Behavior ◽  
Escape Behavior ◽  
Food Sources ◽  
Defensive Strategy ◽  
Sensory Stimuli ◽  
Defensive Behaviors ◽  
Spatial Environment ◽  
Defensive Action ◽  
Access To Food ◽  
Innate Behaviors

SummaryInstinctive defensive behaviors are essential for animal survival. Across the animal kingdom there are sensory stimuli that innately represent threat and trigger stereotyped behaviors such as escape or freezing [1-4]. While innate behaviors are considered to be hard-wired stimulus-responses [5], they act within dynamic environments, and factors such as the properties of the threat [6-9] and its perceived intensity [1, 10, 11], access to food sources [12-14] or expectations from past experience [15, 16], have been shown to influence defensive behaviors, suggesting that their expression can be modulated. However, despite recent work [2, 4, 17-21], little is known about how flexible mouse innate defensive behaviors are, and how quickly they can be modified by experience. To address this, we have investigated the dependence of escape behavior on learned knowledge about the spatial environment, and how the behavior is updated when the environment changes acutely. Using behavioral assays with innately threatening visual and auditory stimuli, we show that the primary goal of escape in mice is to reach a previously memorized shelter location. Memory of the escape target can be formed in a single shelter visit lasting less than 20 seconds, and changes in the spatial environment lead to a rapid update of the defensive action, including changing the defensive strategy from escape to freezing. Our results show that while there are innate links between specific sensory features and defensive behavior, instinctive defensive actions are surprisingly flexible and can be rapidly updated by experience to adapt to changing spatial environments.

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