Fungal Tissue Research Articles

The influence of storage conditions on the dynamics of physicochemical markers of champignon (Agaricus bisporus) quality

Agaricus bisporus are the most common cultivated mushrooms. Champignons are a source of chitin, glycogen and minerals, and also have attractive organoleptic properties. Physicochemical and organoleptic characteristics of fresh Agaricus bisporus undergo significant changes during storage due to moisture transpiration, respiration and oxidative processes. The purpose of this work was to study the influence of storage conditions of cultivated champignons with unstained cap epithelium on the dynamics of their physicochemical parameters, as well as its relationship with changes in organoleptic parameters. The mushrooms were stored in refrigerated chambers at a constant temperature of +2 °C and +6 °C in polypropylene trays placed in bags made of biaxially oriented polypropylene (BOPP) perforated film and polyethylene (PE) film without perforation. Under all storage conditions studied, the nature of the dynamics of physicochemical parameters was close to linear (with the exception of the humidity of fruiting bodies when stored in PE film) — the calculated values of the Pearson correlation coefficient ranged from 0.67 to 0.97. Using two-factor analysis of variance, the influence of both packaging material and storage temperature on the dynamics of soluble solids content and mushroom tissue density was confirmed. When stored in PE film without perforation, a more intense negative dynamics of these criteria was observed compared to storage in perforated BOPP film. The identified difference is explained by the fact that in packaging made of PE film without perforation, conditions for anaerobic respiration were formed by the end of storage — the oxygen content decreased from 20.5% to 1.5–2.5%, which also contributed to the activation of decay processes. With increasing storage temperature, a more intense change in physicochemical parameters was observed, which was associated with an increase in metabolic rate. The relationship between the dynamics of all studied physicochemical quality markers and the dynamics of sensory assessments (with the exception of the marker "content of soluble solids" when stored in a perforated BOPP film at a temperature of 2 °C) has been statistically confirmed. Based on the results of the studies, the applicability of the criteria “humidity of fruiting bodies”, “content of soluble dry substances” and “density of fungal tissue” as markers for assessing the quality of cultivated Agaricus bisporus was confirmed.

Non-canonical IL-22 receptor signaling remodels the mucosal barrier during fungal immunosurveillance.

Mucosal barrier integrity is vital for homeostasis with commensal organisms while preventing pathogen invasion. We unexpectedly found that fungal-induced immunosurveillance enhances resistance to fungal outgrowth and tissue invasion by remodeling the oral mucosal epithelial barrier in mouse models of adult and neonatal Candida albicans colonization. Epithelial subset expansion and tissue remodeling were dependent on interleukin-22 (IL-22) and signal transducer and activator of transcription 3 (STAT3) signaling, through a non-canonical receptor complex composed of glycoprotein 130 (gp130) coupled with IL-22RA1 and IL-10RB. Immunosurveillance-induced epithelial remodeling was restricted to the oral mucosa, whereas barrier architecture was reset once fungal-specific immunity developed. Collectively, these findings identify fungal-induced transient mucosal remodeling as a critical determinant of resistance to mucosal fungal infection during early stages of microbial colonization.

Optimal liquid-based DNA preservation for DNA barcoding of field-collected fungal specimens

Preserving fungal tissue DNA in the field is essential for molecular ecological research, enabling the study of fungal biodiversity and community dynamics. This study systematically compares two liquid-based preservation solutions, RNAlater and DESS, for their effectiveness in maintaining macrofungi DNA integrity during field collection and storage. The research encompasses both controlled experiments and real-world field collections. In the controlled experiments, two fungal species were preserved in RNAlater and DESS at different temperatures and durations. DNA extraction success rates were high, but DNA quality and quantity metrics exhibited variations across samples. However, both preservation solutions demonstrated their viability for preserving fungal DNA, with no significant differences between them. In the field-collected macrofungi experiment, 160 paired fungal specimens were preserved in RNAlater and DESS, respectively. Including a drying process to facilitate tissue lysis for DNA extraction significantly impacted the outcomes. RNAlater showed a higher success rate and better DNA quality and quantity compared to DESS. Statistical analysis, including paired and independent t-tests, confirmed significant differences in DNA quality and quantity between the two preservation methods for field-collected samples. This study evaluates RNAlater and DESS for preserving macrofungi DNA in field conditions. Both methods are effective, but RNAlater is superior when a drying step is included in DNA extraction. Researchers can choose based on their specific needs without compromising DNA integrity. These findings advance fungal molecular ecology and DNA preservation strategies in ecological and environmental studies.

Fungal cryopreservation across 61 genera: Practical application and method evaluation

ABSTRACT Fungi occupy important environmental, cultural, and socioeconomic roles. However, biological research of this diverse kingdom has lagged behind that of other phylogenetic groups. This is partially the result of the notorious difficulty in culturing a diverse array of filamentous fungal species due to their (i) often unpredictable growth, (ii) unknown preferences for culturing conditions, and (iii) long incubation times compared with other microorganisms such as bacteria and yeasts. Given the complexity associated with concurrently culturing diverse fungal species, developing practical methods for preserving as many species as possible for future research is vital. The widely accepted best practice for preserving fungal tissue is the use of cryogenic biobanking at −165 C, allowing for the preservation and documentation of stable genetic lineages, thus enabling long-term diversity-centered research. Despite the extensive literature on fungal cryopreservation, substantial barriers remain for implementation of cryogenic biobanks in smaller mycological laboratories. In this work, we present practical considerations for the establishment of a fungal culture biobank, as well as provide evidence for the viability of 61 fungal genera in cryogenic storage. By providing a pragmatic methodology for cryogenically preserving and managing many filamentous fungi, we show that creating a biobank can be economical for independently owned and operated mycology laboratories, which can serve as a long-term resource for biodiversity, conservation, and strain maintenance.

Sinonasal Tumors Masquerading as Invasive Fungal Sinusitis (IFS).

Fungal tissue invasion in the setting of sinonasal malignancy has been rarely described in the literature. Only a handful of studies have discussed cases of suspected chronic and acute IFS (CIFS and AIFS, respectively), having an underlying undifferentiated sinonasal carcinoma, sinonasal teratocarcinosarcoma, and NK/T-cell lymphoma. Here, we describe 3 cases of carcinoma mimicking IFS from a single institution. Each of our patients presented with sinonasal complaints as an outpatient in the setting of immunosuppression. Intranasal biopsies consistently were predominated by necrotic debris, with and without fungal elements, ultimately leading to a delay of oncologic care. The final pathologies included NK/T-cell lymphoma and SNEC. All patients were followed by radiation and chemotherapy, with 1 case of mortality. We aim to emphasize the importance of obtaining viable tissue as pathology specimens as the presence of necrosis with fungal elements may limit the diagnosis and ultimately delay the care of an underlying sinonasal carcinoma.

Fungal Tissue as a Medium for Electrical Signal Transmission: A Baseline Assessment With Melanized Fungus Curvularia Lunata

Fungal Tissue as a Medium for Electrical Signal Transmission: A Baseline Assessment With Melanized Fungus <i>Curvularia Lunata</i>

Cost-Effective DNA Extraction for DNA Barcoding Diverse Biological Samples.

DNA barcoding employs standard molecular techniques (e.g., DNA extraction, PCR, and Sanger sequencing) to taxonomically identify biological samples. While DNA barcoding is a useful experimental workflow for in-class active learning exercises, extracting DNA from diverse sample types in a time and cost-effective manner can be challenging in a classroom setting. Here, we provide two time and cost-effective methods that have been used by novice students to successfully extract DNA from a variety of animal, fungal, algal, and plant tissues for DNA barcoding.

Use of image analysis to assess radial growth of Passalora arachidicola and Nothopassalora personata on solid media

ABSTRACT Despite significant research on early and late leaf spot diseases of peanut, in vitro study of the respective causal agents, Passalora arachidicola and Nothopassalora personata, has been limited due to cultural challenges that make growth of these fungi difficult to quantify with traditional methods. Studies were conducted to evaluate the practicality of image analysis to assess radial growth and tissue volume by correlating these assessments to dry mass. Image analysis was also used to estimate radial growth rates for these fungi over time. Tissue area and volume were significantly correlated to dry mass for P. arachidicola in two separate experiments, and for N. personata when medium had been removed from tissues prior to dry mass assessments. Tissue area densities were the same for P. arachidicola and Pseudocercospora smilacicola, evaluated as a nonstromatal cercosporoid comparison, whereas tissue volume densities were greater for P. archidicola and N. personata than P. smilacicola. A quadratic relationship was observed between radial growth and incubation time for all isolates evaluated. Growth rates of P. arachidicola isolates were 2 to 4 times faster than N. personata during the first week of incubation and slowed over time. Growth rates of NP18R, a phenotype variant of N. personata, increased after neighboring colonies met and was nearly 2.5 times faster than the fastest rates observed for P. arachidicola. These experiments demonstrate that when fungal tissues are observable, image analysis is a useful assessment tool for P. arachidicola and N. personata. Care should be taken to monitor fungal phenotypic changes in these species because phenotype degeneration can affect growth rates.

Fungal metabolism and free amino acid content may predict nitrogen transfer to the host plant in the ectomycorrhizal relationship between Pisolithus spp. and Eucalyptus grandis.

Ectomycorrhizal (ECM) fungi are crucial for tree nitrogen (N) nutrition; however, mechanisms governing N transfer from fungal tissues to the host plant are not well understood. ECM fungal isolates, even from the same species, vary considerably in their ability to support tree N nutrition, resulting in a range of often unpredictable symbiotic outcomes. In this study, we used isotopic labelling to quantify the transfer of N to the plant host by isolates from the ECM genus Pisolithus, known to have significant variability in colonisation and transfer of nutrients to a host. We considered the metabolic fate of N acquired by the fungi and found that the percentage of plant N acquired through symbiosis significantly correlated to the concentration of free amino acids in ECM extra-radical mycelium. Transcriptomic analyses complemented these findings with isolates having high amino acid content and N transfer showing increased expression of genes related to amino acid transport and catabolic pathways. These results suggest that fungal N metabolism impacts N transfer to the host plant in this interaction and that relative N transfer may be possible to predict through basic biochemical analyses.

Positioning absorptive root respiration in the root economics space across woody and herbaceous species

Abstract1. Root respiration is essential for nutrient acquisition. The respiration rate of absorptive roots theoretically relates to the economics of carbon‐nutrient exchange, but its empirical role remains largely unexplored in the trait space defining nutrient uptake strategies.2. Here, we measured the respiration rates of the distal, non‐woody, absorptive roots of 252 woody and herbaceous species from subtropical and temperate climate zones, including both arbuscular mycorrhizal and ectomycorrhizal fungal hosts.3. We found a consistent and positive correlation between root respiration rate and specific root length (root length per dry weight), irrespective of growth form, mycorrhizal type and climate zone. Root respiration rate was also positively, but less strongly and less frequently correlated with root nitrogen concentration. Root morphology strongly explained the fast‐slow gradient of root respiration in the root economics space.4. By quantifying the ratio of arbuscular mycorrhizal fungal DNA copy number and root tissue DNA copy number using qPCR, we found that the morphology‐driven gradient did not explain the full variation in fungal collaboration; thick roots were consistently well colonised, but medium and thin roots displayed a wide range of colonisation intensity.5. Synthesis: These results advance our understanding of the fundamental trait relationships that underpin the root economics space. Our study also provides a physiological linkage to the frequently measured root morphological traits and relates the root economics space to root‐derived carbon‐nutrient cycling processes.

Fast preparation of high-quality viral dsRNA from fungal tissue by commercial nucleic acid extraction kits

The genomes of most known mycoviruses consist of double stranded RNA (dsRNA) or single stranded RNA (ssRNA). Therefore, for all aspects of mycovirology, the research is highly dependent on the quality and quantity of RNA either by the extraction of genomic dsRNA or dsRNA as a replicating intermediate. A common procedure to extract dsRNA is its binding on a cellulose matrix after a phenol/chloroform purification step. A commercial kit for dsRNA extraction facilitated the researchers´ daily work, but is not available anymore. To extract nucleic acids in a standardized good quality and quantity from small amounts of starting material, we compared commercial kits for gDNA extraction to the kits for RNA extraction using fungal material with a high and a low virus titer. Here we show that viral dsRNA can be extracted using commercial gDNA kits from fungal tissue with a high and a low virus titer in the same quality and quantity as it was done with the discontinued dsRNA extraction kit.

Improved Double-Stranded RNA Extraction and Hyphal Tip-Touch Techniques for the Detection of Mycoviruses

Mycoviruses infect a wide range of fungal species, and many of them have double-stranded RNA (dsRNA) genomes. Using a dsRNA technique makes it easier to detect unknown mycoviruses in fungi. Previously, a few studies reported dsRNA extraction methods from fungal tissues, but the procedures required a significant amount of starting material and time, particularly in growing fungal cultures. In this study, we report an efficient and quick dsRNA extraction method that is reproducible to extract quality dsRNA of mycoviruses from a small amount of fungal culture in a short time. Extracted dsRNA was subsequently used in Illumina sequencing and reverse transcription-polymerase chain reaction assays, followed by Sanger sequencing, to confirm the identity of the mycovirus. Additionally, a rapid and efficient technique named hyphal tip-touch (HTT) was developed to identify known mycoviruses without the need for dsRNA extraction. The HTT technique uses the edge of mycelia as a template for preparing complementary DNA in the reverse transcription reaction, which was used in the polymerase chain reaction assay followed by sequencing. [Formula: see text] Copyright © 2024 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license .

Endophytic ancestors of modern leaf miners may have evolved in the Late Carboniferous.

Endophytic feeding behaviors, including stem borings and galling, have been observed in the fossil record from as early as the Devonian and involve the consumption of a variety of plant (and fungal) tissues. Historically, the exploitation of internal stem tissues through galling has been well documented as emerging during the Pennsylvanian (c. 323-299 million years ago (Ma)), replaced during the Permian by galling of foliar tissues. However, leaf mining, a foliar endophytic behavior that today is exhibited exclusively by members of the four hyperdiverse holometabolous insect orders, has been more sparsely documented, with confirmed examples dating back only to the Early Triassic (c. 252-250 Ma). Here, we describe a trace fossil on seed-fern foliage from the Rhode Island Formation of Massachusetts, USA, representing the earliest indication of a general, endophytic type of feeding damage and dating from the Middle Pennsylvanian (c. 312 Ma). Although lacking the full features of Mesozoic leaf mines, this specimen provides evidence of how endophytic mining behavior may have originated. It sheds light on the evolutionary transition to true foliar endophagy, contributes to our understanding of the behaviors of early holometabolous insects, and enhances our knowledge of macroevolutionary patterns of plant-insect interactions.

A Disease-Specific Antibiogram to Evaluate Empiric Coverage Patterns in Fournier’s Gangrene

To analyze our local antibiogram and antibiotic resistance patterns given concern for multidrug-resistant and fungal organisms in contemporary series detailing causative organisms in Fournier's Gangrene (FG). All patients from 2018 to 2022 were identified from the institutional FG registry. Microorganisms and sensitivities were collected from operative tissue cultures. The primary outcome of this study was the adequacy of our empiric. Secondary outcomes included the rate of bacteremia, the concordance of blood cultures and tissue cultures, and the rate of fungal tissue infections. Escherichia coli and Streptococcus anginosus were most common, identified in 12 patients each (20.0%). Enterococcus faecalis (9, 15.0%), S agalactiae (8, 13.3%) and mixed cultures without a predominant organism (9, 15.0%) were also common. A fungal organism was identified in 9 (15.0%) patients. Patients who were started on Infectious Diseases Society of America guideline adherent antibiotic regimen were not significantly different in terms of bacteremia rate (P=.86), mortality (P=.25), length of stay (P=.27), or final antibiotic duration (P=.43) when compared to those on alternative regimens. Patients with a tissue culture positive for a fungal organism were not significantly different in terms of Fournier's Gangrene Severity Index (P=.25) or length of stay (P=.19). Local disease-specific antibiograms can be a powerful tool to guide empiric antibiotic therapy in FG. Although fungal infections are responsible for a majority of the gaps in empiric antimicrobial coverage at our institution they were present in only 15% of patients and their effect on outcomes does not justify addition of empiric antifungal agents.

Primary inoculum of Venturia inaequalis (Cooke) Wint. in its asexual form in apple – a review

This review summarizes and discusses the geographical distribution, overwintering, dissemination, and management of the asexual stage of Venturia inaequalis, the fungal pathogen causing apple scab. The asexual overwintering of V. inaequalis has primarily been described as wood scab, superficial scab, or bud scab, and more rarely, it is mentioned as overwintering on infected leaves and fruits still attached to the trees. Wood scab is fungal pustules found on new and 1-year-old shoots, but it is also found on 2-year-old wood. It has been reported in many apple-growing countries throughout the world; however, most reports of wood scab being an important source of primary inoculum, as well as the most in-depth studies, are from the UK. Reports from some countries describe what is named superficial scab, which are symptomless infections of the pathogen on shoot surfaces. Overwintering of V. inaequalis on the inner or outer bud scales has also been reported in some countries. Infections may appear as small lesions on the bud scales, but numerous conidia have also been found in buds without symptomatic fungal tissue. The incidence and quantity of overwintering in the asexual stage are dependent on the amount of scab in the previous season, growth characteristics, and cultivar susceptibility. In orchards with limited options for fungicide control and/or in orchards with loss of scab control in the preceding season, conidia of V. inaequalis should not be underestimated as a source of primary inoculum.

Production of Food Mushrooms (Lentinula edodes) Isolated from the Iraqi Environment Using Agricultural Waste

Shiitake mushroom Lentinula edodes have been a part of the human diet since ancient times. Mushrooms have gained a lot of attention lately due to their prospects in medicine and nutrient production. Due to the lack of research studies on this fungus globally, particularly in Iraq, this study is considered the first in which agricultural waste is used to produce local food mushrooms. The local strain L. edodes (OM432157), which was discovered for the first time in the Iraqi environment, was cultivated in the laboratory using nine treatments based on sawdust as the main substrate. It was observed that the highest growth rate of the fungus strain under study was in T8 (1.8 cm) and the lowest growth rate in T5 was 1.1 (cm). Fungal tissue growth in treatments (T4, T5) required (29 days), while in treatment T8 it required (26 days), and in other remaining treatments it accomplished in 25 days. The time required for pin heads to form in T5 was obviously faster (17 days), followed by T8 (18 days) and T9 (19 days). In addition, that both treatments (T5, T9) achieved a high yield of mushroom, as T5 was 250 gm, and treatment T8 reached 200 gm. Our findings contributes to product the local strain L. edodes (OM432157) wild in the laboratory by using different substrates.

Fungus and fruit consumption by harvestmen and spiders (Opiliones, Araneae): the vegetarian side of two predominantly predaceous arachnid groups

In this review, we report on harvestmen and spiders feeding on fungi, fruits, and seeds. Fungivory in harvestmen is widespread, with most reports referring to tropical species in the family Sclerosomatidae, which consume mainly small forest mushrooms (families Marasmiaceae and Mycenaceae). In contrast, consumption of fungal material by spiders apparently occurs only if airborne spores trapped in the viscid threads of orb-webs (e.g., Araneidae and Tetragnathidae) are ingested along with old webs prior to the construction of new webs. Consumption of fruit pulp by harvestmen is also widespread, with several records of Leiobunum spp. (Sclerosomatidae) feeding on Rubus spp. berries and other lipid-poor fruits in the Holarctic region. In Neotropical forests, harvestmen in the families Cosmetidae and Gonyleptidae feed on lipid-poor pulp of fallen fruits. Among spiders, we document several cases of synanthropic species opportunistically feeding on fruit waste (e.g., pieces of banana, papaya, watermelon, or orange pulp) inside houses or disposed in yards. Only one case of a spider feeding on a wild fruit in the field was found in our search. Finally, we report several cases of harvestmen and spiders feeding on elaiosomes or arils (i.e., lipid-rich seed appendages). In conclusion, harvestmen consume mushrooms, fruit pulp, seeds, and seed appendages more frequently than spiders probably because they are “solid food feeders”, which means they can ingest solid tissues by biting off small pieces. In turn, spiders are “fluid feeders” and feed on vegetable matter most frequently in the form of fluids (e.g., nectar, stigmatic exudate, plant sap, and honey dew), rather than fungal or plant tissues.

Bloody tears as initial manifestation of rhino-orbital mucormycosis.

Bloody tears as initial manifestation of rhino-orbital mucormycosis.

Alcobiosis, an algal-fungal association on the threshold of lichenisation

Alcobiosis, the symbiosis of algae and corticioid fungi, frequently occurs on bark and wood. Algae form a layer in or below fungal basidiomata reminiscent of the photobiont layer in lichens. Identities of algal and fungal partners were confirmed by DNA barcoding. Algal activity was examined using gas exchange and chlorophyll fluorescence techniques. Carbon transfer from algae to fungi was detected as 13C, assimilated by algae, transferred to the fungal polyol. Nine fungal partners scattered across Agaricomycetes are associated with three algae from Trebouxiophycae: Coccomyxa sp. with seven fungal species on damp wood, Desmococcus olivaceus and Tritostichococcus coniocybes, both with a single species on bark and rain-sheltered wood, respectively. The fungal partner does not cause any obvious harm to the algae. Algae enclosed in fungal tissue exhibited a substantial CO2 uptake, but carbon transfer to fungal tissues was only detected in the Lyomyces-Desmococcus alcobiosis where some algal cells are tightly enclosed by hyphae in goniocyst-like structures. Unlike lichen mycobionts, fungi in alcobioses are not nutritionally dependent on the algal partner as all of them can live without algae. We consider alcobioses to be symbioses in various stages of co-evolution, but still quite different from true lichens.

Histologic findings of Massospora cicadina infection in periodical cicadas (Magicicada septendecim).

Massospora cicadina, an obligate fungal pathogen in the subphylum Entomophthoromycotina (Zoopagomycota), infects periodical cicadas (Magicicada spp.) during their adult emergence and modifies their sexual behavior to maximize fungal spore dissemination. In this study, 7 periodical cicadas from the Brood X emergence in 2021 infected by M. cicadina were histologically examined. In 7 of 7 cicadas, fungal masses replaced the posterior portion of the abdominal cavity, effacing portions of the body wall, reproductive organs, alimentary tract, and fat bodies. No appreciable inflammation was noted at the intersections of the fungal masses and host tissues. Fungal organisms were present in multiple morphologies including protoplasts, hyphal bodies, conidiophores, and mature conidia. Conidia were clustered into eosinophilic membrane-bound packets. These findings help uncover the pathogenesis of M. cicadina by suggesting there is evasion of the host immune response and by providing a more in-depth description of its relationship with Magicicada septendecim than previously documented.