Ageritin from Pioppino Mushroom: The Prototype of Ribotoxin-Like Proteins, a Novel Family of Specific Ribonucleases in Edible Mushrooms

Ageritin is a specific ribonuclease, extracted from the edible mushroom Cyclocybe aegerita (synonym Agrocybe aegerita), which cleaves a single phosphodiester bond located within the universally conserved alpha-sarcin loop (SRL) of 23–28S rRNAs. This cleavage leads to the inhibition of protein biosynthesis, followed by cellular death through apoptosis. The structural and enzymatic properties show that Ageritin is the prototype of a novel specific ribonucleases family named ‘ribotoxin-like proteins’, recently found in fruiting bodies of other edible basidiomycetes mushrooms (e.g., Ostreatin from Pleurotus ostreatus, Edulitins from Boletus edulis, and Gambositin from Calocybe gambosa). Although the putative role of this toxin, present in high amount in fruiting body (>2.5 mg per 100 g) of C. aegerita, is unknown, its antifungal and insecticidal actions strongly support a role in defense mechanisms. Thus, in this review, we focus on structural, biological, antipathogenic, and enzymatic characteristics of this ribotoxin-like protein. We also highlight its biological relevance and potential biotechnological applications in agriculture as a bio-pesticide and in biomedicine as a therapeutic and diagnostic agent.

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Lessons on fruiting body morphogenesis from genomes and transcriptomes of Agaricomycetes

10.1101/2021.12.09.471732 ◽

2021 ◽

Author(s):

Laszlo G Nagy ◽

Peter Jan Vonk ◽

Markus Kunzler ◽

Csenge Foldi ◽

Mate Viragh ◽

...

Keyword(s):

Cell Wall ◽

Fruiting Body ◽

Expression Patterns ◽

Schizophyllum Commune ◽

Gene Families ◽

Second Phase ◽

Fruiting Bodies ◽

Body Development ◽

Fruiting Body Development

Fruiting bodies of mushroom-forming fungi (Agaricomycetes) are among the most complex structures produced by fungi. Unlike vegetative hyphae, fruiting bodies grow determinately and follow a genetically encoded developmental program that orchestrates tissue differentiation, growth and sexual sporulation. In spite of more than a century of research, our understanding of the molecular details of fruiting body morphogenesis is limited and a general synthesis on the genetics of this complex process is lacking. In this paper, we aim to comprehensively identify conserved genes related to fruiting body morphogenesis and distill novel functional hypotheses for functionally poorly characterized genes. As a result of this analysis, we report 921 conserved developmentally expressed gene families, only a few dozens of which have previously been reported in fruiting body development. Based on literature data, conserved expression patterns and functional annotations, we provide informed hypotheses on the potential role of these gene families in fruiting body development, yielding the most complete description of molecular processes in fruiting body morphogenesis to date. We discuss genes related to the initiation of fruiting, differentiation, growth, cell surface and cell wall, defense, transcriptional regulation as well as signal transduction. Based on these data we derive a general model of fruiting body development, which includes an early, proliferative phase that is mostly concerned with laying out the mushroom body plan (via cell division and differentiation), and a second phase of growth via cell expansion as well as meiotic events and sporulation. Altogether, our discussions cover 1480 genes of Coprinopsis cinerea, and their orthologs in Agaricus bisporus, Cyclocybe aegerita, Armillaria ostoyae, Auriculariopsis ampla, Laccaria bicolor, Lentinula edodes, Lentinus tigrinus, Mycena kentingensis, Phanerochaete chrysosporium, Pleurotus ostreatus, and Schizophyllum commune, providing functional hypotheses for ~10% of genes in the genomes of these species. Although experimental evidence for the role of these genes will need to be established in the future, our data provide a roadmap for guiding functional analyses of fruiting related genes in the Agaricomycetes. We anticipate that the gene compendium presented here, combined with developments in functional genomics approaches will contribute to uncovering the genetic bases of one of the most spectacular multicellular developmental processes in fungi. Key words: functional annotation; comparative genomics; cell wall remodeling; development; fruiting body morphogenesis; mushroom; transcriptome

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Comparative Study of Pleurotus ostreatus Mushroom Grown on Modified PAN Nanofiber Mats

Nanomaterials ◽

10.3390/nano9030475 ◽

2019 ◽

Vol 9 (3) ◽

pp. 475 ◽

Cited By ~ 9

Author(s):

Lilia Sabantina ◽

Franziska Kinzel ◽

Thomas Hauser ◽

Astrid Többer ◽

Michaela Klöcker ◽

...

Keyword(s):

Comparative Study ◽

Growth Rates ◽

Pleurotus Ostreatus ◽

Edible Mushroom ◽

Fungal Mycelium ◽

Specific Substrate ◽

Biotechnological Applications ◽

Mushroom Species ◽

Nanofiber Mats ◽

Pan Nanofiber

Pleurotus ostreatus is a well-known edible mushroom species which shows fast growth. The fungus can be used for medical, nutritional, filter, or packaging purposes. In this study, cultivation experiments were carried out with Pleurotus ostreatus growing on polyacrylonitrile (PAN) nanofiber mats in the presence of saccharose and Lutrol F68. The aim of this study was to find out whether modified PAN nanofiber mats are well suited for the growth of fungal mycelium, to increase growth rates and to affect mycelium fiber morphologies. Our results show that Pleurotus ostreatus mycelium grows on nanofiber mats in different morphologies, depending on the specific substrate, and can be used to produce a composite from fungal mycelium and nanofiber mats for biomedical and biotechnological applications.

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First Report of Cladobotryum protrusum causing Cobweb Disease on the Edible Mushroom Coprinus comatus

Plant Disease ◽

10.1094/pdis-07-14-0757-pdn ◽

2015 ◽

Vol 99 (2) ◽

pp. 287-287 ◽

Cited By ~ 6

Author(s):

G. Z. Wang ◽

M. P. Guo ◽

Y. B. Bian

Keyword(s):

Fruiting Body ◽

Morphological Characteristics ◽

Edible Mushroom ◽

Its2 Region ◽

Pathogenicity Test ◽

Distilled Water ◽

Fruiting Bodies ◽

Coprinus Comatus ◽

First Report ◽

Medicinal Value

Coprinus comatus is one of the most commercially important mushrooms in China. Its fruiting body possesses rich nutritional and medicinal value. In November 2013, unusual symptoms were observed on C. comatus on a mushroom farm in Wuhan, Hubei, China. At first, fruiting bodies were covered by white and cobweb-like mycelia. Later, the cap and stipe turned brown or dark before rotting and cracking. The pathogen was isolated from infected tissue of C. comatus. Colonies of the pathogen on potato dextrose agar (PDA) medium first appeared yellowish, followed by an obvious ochraceous or pinkish color. Aerial mycelia grew along the plate wall, cottony, 1 to 4 mm high. Conidiophores were borne on the tops of hyphae, had two to four branches, and were cylindrical, long clavate, or fusiform. Conidia were borne on the tops of the branches of conidiophores, had one to two separates, and were long and clavate. The spores ranged from 15.3 to 22.1 μm long and were 5.1 to 8.3 μm wide, which was consistent with the characteristics of Cladobotryum protrusum (1). The species was identified by ribosomal internal transcribed spacer sequencing. The ribosomal ITS1-5.8S-ITS2 region was amplified from the isolated strain using primers ITS1 and ITS4. A BLAST search in GenBank revealed the highest similarity (99%) to C. protrusum (GenBank Accession Nos. FN859408.1 and FN859413.1). The pathogen was grown on PDA at 25°C for 3 days, and the inoculation suspension was prepared by flooding the agar surface with sterilized double-distilled water for spore suspension (1 × 105 conidia/ml). In one treatment, the suspension was sprayed on casing soil (106 conidia/m2) and mixed thoroughly with it, then cased with treated soil for 2 to 3 cm thickness on the surface of compost in cultivation pots (35 × 25× 12 cm), with sterile distilled water as a control (2). Eight biological replicates were included in this treatment. In the second treatment, mycelia plugs (0.3 × 0.3 cm) without spore production were added to 20 fruiting bodies. Mushrooms treated with blank agar plugs (0.3 × 0.3 cm) were used as a control. The plugs were covered with sterilized cotton balls to avoid loss of moisture. Tested cultivation pots were maintained at 18°C and 85 to 95% relative humidity. In the samples where casing soil was sprayed with conidia suspension, white mildew developed on the pileus, and a young fruiting body grew out from the casing soil. Eventually, the surface of the mushroom was overwhelmed by the mycelia of the pathogen and the pileus turned brown or black. For the other group inoculated with mycelia plugs, only the stipe and pileus inoculated with mycelia turned brown or dark; it rotted and cracked 2 to 3 days later. The symptoms were similar to those observed on the C. comatus cultivation farm. Pathogens re-isolated from pathogenic fruiting bodies were confirmed to be C. protrusum based on morphological characteristics and ITS sequence. To our knowledge, this is the first report of the occurrence of C. protrusum on the edible mushroom C. comatus (3). Based on the pathogenicity test results, C. protrusum has the ability to severely infect the fruiting body of C. comatus. References: (1) K. Põldmaa. Stud. Mycol. 68:1, 2011. (2) F. J. Gea et al. Plant Dis. 96:1067, 2012. (3) W. H. Dong et al. Plant Dis. 97:1507, 2013.

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The tripartite relationship in gill-knot disease of the oyster mushroom, Pleurotus ostreatus (Jacq.: Fr.) Kummer

Canadian Journal of Zoology ◽

10.1139/z96-155 ◽

1996 ◽

Vol 74 (8) ◽

pp. 1402-1408 ◽

Cited By ~ 8

Author(s):

Kaku Tsuda ◽

Kazuyoshi Futai ◽

Hajime Kosaka

Keyword(s):

Adult Female ◽

Adult Male ◽

Fruiting Body ◽

Pleurotus Ostreatus ◽

Laboratory Experiments ◽

Oyster Mushroom ◽

Fruiting Bodies ◽

Fungus Gnat ◽

Western Japan ◽

Tripartite Relationship

A disease that causes knots on the gills of the oyster mushroom, Pleurotus ostreatus, has been reported from western Japan. Nematodes inhabit and lay many eggs inside the gill knots. It is surprising that the nematodes causing this disease live in the fruiting body of this fungus, which is known to be nematophagous. In the present study, the fungus gnat Rhymosia domestica (Mycetophilidae, Diptera) was confirmed to be the vector of the nematodes inside the gill knots. This nematode has different adult stages, i.e., a mycetophagous adult female, an adult female infective to the fungus gnat, an adult male, and a mature entomophagous adult female. The occurrence of gill-knot disease was investigated in the field. Laboratory experiments determined that the fungus gnat could not itself form gill knots, because formation of knots was not observed on the gills of fruiting bodies incubated with nematode-free gnats. Observation by means of microscopy and the spore patterns of diseased fruiting bodies confirmed that the knots consist of dedifferentiated hyphal tissues, which do not form spores.

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Use of Different Agro-wastes in the Cultivation of Pleurotus ostreatus (Jacq.) Kummer

Journal of Bioresource Management ◽

10.35691/jbm.0202.0129 ◽

2020 ◽

Vol 7 (2) ◽

pp. 29-38

Author(s):

Mary Iwuagwu ◽

Deborah Nwaukwa ◽

Chidi Nwaru

Keyword(s):

Pleurotus Ostreatus ◽

Urban Areas ◽

Growth Period ◽

Edible Mushroom ◽

Growth And Yield ◽

Fruiting Bodies ◽

Corn Straw ◽

Rural And Urban Areas ◽

Rural And Urban ◽

Randomized Design

Agro-wastes are abundant in both rural and urban areas and when carelessly disposed off to the environment by dumping or burning, they lead to environmental pollution, and consequently to health hazards. Growing of edible mushroom on these wastes can contribute to decrease in environment pollution. This work investigated the growth and yield of Pleurotus ostreatus on different agro-wastes: plantain midrib (PM), corn straw (CS), sugarcane bagasse (SB) and their combinations (PM+CS, PM+SB, CS+SB, CS+PM+SB) with a view to finding the best substrate for the growth of P. ostreatus. The experiment was carried out using completely randomized design with seven treatments and three replications. Results revealed that mycelia growth period and days to pinhead formation were faster in corn straw (7 and 11 days, respectively from the day of inoculation), this was followed by CS+SB (8 and 12 days, respectively) while CS+PM+SB recorded the longest days (13 and 17, respectively). Stipe length ranged from 2.6 cm in PM to 3.3 cm in CS+PM while the pileus diameter was between 3.3 cm in CS and PM and 4.3 cm in PM+SB. Number of fruiting bodies, fresh and dry weights of the mushroom were significantly higher in CS than in the other substrates. The least number of fruiting bodies, fresh and dry weights were recorded in CS+PM+SB.

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Antimicrobial Activity and Identification The Compounds of Methanol Extract from The Pleurotus Ostreatus Fruiting Body

el–Hayah ◽

10.18860/elha.v6i1.4082 ◽

2017 ◽

Vol 6 (1) ◽

pp. 29

Author(s):

Muhammad Evy Prastiyanto ◽

Sri Darmwati ◽

Arya Iswara ◽

Agnis Setyaningtyas ◽

Laily Trisnawati ◽

...

Keyword(s):

Antimicrobial Activity ◽

Fruiting Body ◽

Pleurotus Ostreatus ◽

Enterobacter Aerogenes ◽

Edible Mushroom ◽

Zone Of Inhibition ◽

Diffusion Technique ◽

Dragendorff Reagent ◽

Growth Of Fungi ◽

Method Analysis

Pleurotus ostreatus is an edible mushroom that also has potential as medicinal values. In this study, fruiting body of P. ostreatus was tested for its ability to inhibit the growth of fungi and bacteria. The fruiting body powder of P. ostreatus was extracted using methanol by maceration method. Analysis of this compound was done by using anisaldehid sulfuric acid, Dragendorff reagent, and FeCl3. Using the agar well diffusion technique, the extracts were tested for their antimicrobial activity against Staphylococcus aureus (Gram positive), Enterobacter aerogenes (Gram negative) and Candida albican (yeast). The spot results on TLC using crude extract of P. ostreatus is terpenoids. Zone of inhibition for the various extracts varied between 10.9 - 23.2 mm. Ten miligrams extract exhibit maximum antimicrobial activity against most of the tested pathogens

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Heterologous Production and Functional Characterization of Ageritin, a Novel Type of Ribotoxin Highly Expressed during Fruiting of the Edible Mushroom Agrocybe aegerita

Applied and Environmental Microbiology ◽

10.1128/aem.01549-19 ◽

2019 ◽

Vol 85 (21) ◽

Cited By ~ 5

Author(s):

Annageldi Tayyrov ◽

Sophie Azevedo ◽

Robert Herzog ◽

Eva Vogt ◽

Simon Arzt ◽

...

Keyword(s):

Protein Biosynthesis ◽

Functional Characterization ◽

Edible Mushroom ◽

Defense Proteins ◽

Content Type ◽

Phosphodiester Bond ◽

Agrocybe Aegerita ◽

Protein Toxin

ABSTRACT Fungi produce various defense proteins against antagonists, including ribotoxins. These toxins cleave a single phosphodiester bond within the universally conserved sarcin-ricin loop of ribosomes and inhibit protein biosynthesis. Here, we report on the structure and function of ageritin, a previously reported ribotoxin from the edible mushroom Agrocybe aegerita. The amino acid sequence of ageritin was derived from cDNA isolated from the dikaryon A. aegerita AAE-3 and lacks, according to in silico prediction, a signal peptide for classical secretion, predicting a cytoplasmic localization of the protein. The calculated molecular weight of the protein is slightly higher than the one reported for native ageritin. The A. aegerita ageritin-encoding gene, AaeAGT1, is highly induced during fruiting, and toxicity assays with AaeAGT1 heterologously expressed in Escherichia coli showed a strong toxicity against Aedes aegypti larvae yet not against nematodes. The activity of recombinant A. aegerita ageritin toward rabbit ribosomes was confirmed in vitro. Mutagenesis studies revealed a correlation between in vivo and in vitro activities, indicating that entomotoxicity is mediated by ribonucleolytic cleavage. The strong larvicidal activity of ageritin makes this protein a promising candidate for novel biopesticide development. IMPORTANCE Our results suggest a pronounced organismal specificity of a protein toxin with a very conserved intracellular molecular target. The molecular details of the toxin-target interaction will provide important insight into the mechanism of action of protein toxins and the ribosome. This insight might be exploited to develop novel bioinsecticides.

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Comparative Proteomic Analysis of Pleurotus ostreatus Reveals Great Metabolic Differences in the Cap and Stipe Development and the Potential Role of Ca2+ in the Primordium Differentiation

International Journal of Molecular Sciences ◽

10.3390/ijms20246317 ◽

2019 ◽

Vol 20 (24) ◽

pp. 6317 ◽

Cited By ~ 1

Author(s):

Weiwei Zhu ◽

Jinbo Hu ◽

Yang Li ◽

Bing Yang ◽

Yanli Guan ◽

...

Keyword(s):

Fruiting Body ◽

Pleurotus Ostreatus ◽

Potential Role ◽

Developmental Process ◽

Underlying Mechanism ◽

Chemical Inducers ◽

Pathway Enrichment ◽

Edible Fungus ◽

First Time

Pleurotus ostreatus is a widely cultivated edible fungus around the world. At present, studies on the developmental process of the fruiting body are limited. In our study, we compared the differentially expressed proteins (DEPs) in the stipe and cap of the fruiting body by high-throughput proteomics. GO and pathway analysis revealed the great differences in the metabolic levels, including sucrose and starch metabolism, and sphingolipid signaling and metabolism, and the differences of 16 important DEPs were validated further by qPCR analysis in expression level. In order to control the cap and stipe development, several chemical inducers were applied to the primordium of the fruiting body according to the pathway enrichment results. We found that CaCl2 can affect the primordium differentiation through inhibiting the stipe development. EGTA (ethyleneglycol bis (β-aminoethyl ether)-N,N,N′,N′-tetraacetic acid) treatment confirmed the inhibitory role of Ca2+ in the stipe development. Our study not only shows great metabolic differences during the cap and stipe development but also reveals the underlying mechanism directing the primordium differentiation in the early development of the fruiting body for the first time. Most importantly, we provide a reliable application strategy for the cultivation and improvement of the Pleurotus ostreatus, which can be an example and reference for a more edible fungus.

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