-
Frontiers in Microbiology 2021Manganese (Mn) oxides are among the strongest oxidants and sorbents in the environment, and Mn(II) oxidation to Mn(III/IV) (hydr)oxides includes both abiotic and...
Manganese (Mn) oxides are among the strongest oxidants and sorbents in the environment, and Mn(II) oxidation to Mn(III/IV) (hydr)oxides includes both abiotic and microbially-mediated processes. While white-rot Basidiomycete fungi oxidize Mn(II) using laccases and manganese peroxidases in association with lignocellulose degradation, the mechanisms by which filamentous Ascomycete fungi oxidize Mn(II) and a physiological role for Mn(II) oxidation in these organisms remain poorly understood. Here we use a combination of chemical and in-gel assays and bulk mass spectrometry to demonstrate secretome-based Mn(II) oxidation in three phylogenetically diverse Ascomycetes that is mechanistically distinct from hyphal-associated Mn(II) oxidation on solid substrates. We show that Mn(II) oxidative capacity of these fungi is dictated by species-specific secreted enzymes and varies with secretome age, and we reveal the presence of both Cu-based and FAD-based Mn(II) oxidation mechanisms in all 3 species, demonstrating mechanistic redundancy. Specifically, we identify candidate Mn(II)-oxidizing enzymes as tyrosinase and glyoxal oxidase in sp. SRC1lsM3a, bilirubin oxidase in sp. and AP3s5-JAC2a, and GMC oxidoreductase in all 3 species, including sp. DS3sAY3a. The diversity of the candidate Mn(II)-oxidizing enzymes identified in this study suggests that the ability of fungal secretomes to oxidize Mn(II) may be more widespread than previously thought.
PubMed: 33643238
DOI: 10.3389/fmicb.2021.610497 -
Microorganisms Apr 2024In the continuous cropping of , the pathogenic fungi in the rhizosphere soil increased and infected the roots of , resulting in a decrease in yield. This is an urgent...
In the continuous cropping of , the pathogenic fungi in the rhizosphere soil increased and infected the roots of , resulting in a decrease in yield. This is an urgent problem that needs to be solved in order to effectively overcome the obstacles associated with the continuous cropping of . Previous studies have shown that inhibits pathogenic fungi in the rhizosphere of , but the inhibitory effect was not stable. Therefore, we hope to introduce biochar to help colonize in soil. In the experiment, fields planted with for 5 years were renovated, and biochar was mixed in at the same time. The applied amount of biochar was set to four levels (B0, 10 kg·hm; B1, 80 kg·hm; B2, 110 kg·hm; B3, 140 kg·hm), and biological agent was set to three levels (C1, 10 kg·hm; C2, 15 kg·hm; C3, 25 kg·hm). The full combination experiment and a blank control group (CK) were used. The experimental results show that the overall decreased by 0.86%~65.68% at the phylum level. increased by -73.81%~138.47%, and increased by -51.27%~403.20%. At the genus level, increased by -10.29%~855.44%, decreased by 35.02%~86.79%, and increased by -93.60%~680.62%. mainly causes acute bacterial wilt root rot, while mainly causes yellow rot. Under different treatments, the Shannon index increased by -6.77%~62.18%, the Chao1 index increased by -12.07%~95.77%, the Simpson index increased by -7.31%~14.98%, and the ACE index increased by -11.75%~96.12%. The good_coverage indices were all above 0.99. The results of a random forest analysis indicated that , , and were the top three most important species in the soil, with MeanDecreaseGini values of 2.70, 2.50, and 2.45, respectively. , the primary pathogen of , ranked fifth, and its MeanDecreaseGini value was 2.28. The experimental results showed that the B2C2 treatment had the best inhibitory effect on , and the relative abundance of in rhizosphere soil decreased by 86.79% under B2C2 treatment; the B1C2 treatment had the best inhibitory effect on , and the relative abundance of in the rhizosphere soil decreased by 93.60% under B1C2 treatment. Therefore, if we want to improve the soil with acute Ralstonia solanacearum root rot, we should use the B2C2 treatment to improve the soil environment; if we want to improve the soil with yellow rot disease, we should use the B1C2 treatment to improve the soil environment.
PubMed: 38674727
DOI: 10.3390/microorganisms12040783 -
International Journal of Molecular... Aug 2023Rhizosphere microbial communities can influence plant growth and development. Natural regeneration processes take place in the tree stands of protected areas, which...
Rhizosphere microbial communities can influence plant growth and development. Natural regeneration processes take place in the tree stands of protected areas, which makes it possible to observe the natural changes taking place in the rhizosphere along with the development of the plants. This study aimed to determine the diversity (taxonomic and functional) of the rhizosphere fungal communities of Norway spruce growing in one of four developmental stages. Our research was based on the ITS region using Illumina system sequencing. Saprotrophs dominated in the studied rhizospheres, but their percentage share decreased with the age of the development group (for 51.91 from 43.13%). However, in the case of mycorrhizal fungi, an opposite trend was observed (16.96-26.75%). The most numerous genera were: saprotrophic (2.54-3.83%), (6.47-12.86%), (1.39-11.78%), pathogenic (0.53-4.39%), and mycorrhizal (1.80-5.46%), (2.94-5.64%) and (4.54-15.94%). The species composition of rhizosphere fungal communities was favorable for the regeneration of natural spruce and the development of multi-generational Norway spruce stands. The ratio of the abundance of saprotrophic and mycorrhizal fungi to the abundance of pathogens was high and promising for the durability of the large proportion of spruce in the Wigry National Park and for forest ecosystems in general.
Topics: Rhizosphere; Abies; Picea; Poland; Parks, Recreational; Mycorrhizae; Pinus; Microbiota; Norway
PubMed: 37628809
DOI: 10.3390/ijms241612628 -
Marine Drugs Jan 2020Microbial co-cultivation is employed for awakening silent biosynthetic gene clusters (BGCs) to enhance chemical diversity. However, the selection of appropriate partners...
Microbial co-cultivation is employed for awakening silent biosynthetic gene clusters (BGCs) to enhance chemical diversity. However, the selection of appropriate partners for co-cultivation remains a challenge. Furthermore, competitive interactions involving the suppression of BGCs or upregulation of known, functional metabolite(s) during co-cultivation efforts is also common. Herein, we performed an alternative approach for targeted selection of the best co-cultivation pair. Eight marine sediment-derived fungi were classified as strong or weak, based on their anti-phytopathogenic potency. The fungi were co-cultured systematically and analyzed for their chemical profiles and anti-phytopathogenic activity. Based on enhanced bioactivity and a significantly different metabolite profile including the appearance of a co-culture specific cluster, the co-culture of (strong) and (weak) was prioritized for chemical investigation. Large-scale co-cultivation resulted in isolation of five polyketide type compounds: two 12-membered macrolides, dendrodolide E () and its new analog dendrodolide N (), as well as two rare azaphilones spiciferinone () and its new analog 8a-hydroxy-spiciferinone (). A well-known -naphtho-γ-pyrone type mycotoxin, cephalochromin (), whose production was specifically enhanced in the co-culture, was also isolated. Chemical structures of compounds - were elucidated by NMR, HRMS and [] analyses. Compound showed the strongest anti-phytopathogenic activity against and with IC values of 0.9 and 1.7 µg/mL, respectively.
Topics: Agrochemicals; Aquatic Organisms; Biological Products; Coculture Techniques; Fungi; Geologic Sediments; Industrial Microbiology; Inhibitory Concentration 50; Magnetic Resonance Spectroscopy; Metabolomics; Phytophthora infestans; Polyketides; Research Design; Xanthomonas campestris
PubMed: 31979232
DOI: 10.3390/md18020073 -
Phytopathology Jun 2021Tomato production in Ohio protected culture systems is hindered by a soilborne disease complex consisting of corky root rot (), black dot root rot (), Verticillium wilt...
Tomato production in Ohio protected culture systems is hindered by a soilborne disease complex consisting of corky root rot (), black dot root rot (), Verticillium wilt (), and root-knot ( and ). In a survey of 71 high tunnels, was detected in 90% of high tunnels, and (46%), (48%), and spp. (45%) were found in nearly half of high tunnels. Anaerobic soil disinfestation (ASD) with wheat bran (20.2 Mg/ha) plus molasses (10.1 Mg/ha) and grafting onto 'Maxifort' or 'Estamino' rootstocks were evaluated in high tunnels on five farms. In post-ASD bioassays of trial soils, root and taproot rot severity were significantly reduced after ASD, and root-knot galling was also reduced by ASD. Soilborne pathogenic fungi were isolated less frequently from bioassay plants grown in ASD-treated soils than control soils. Similar results were observed in tomato plants grown in high tunnels. Root rot was significantly reduced by ASD in nearly all trials. Corky root rot severity was highest in nongrafted plants grown in nontreated soils, and the lowest levels of corky root rot were observed in 'Maxifort'-grafted plants. Black dot root rot severity was higher or equivalent in grafted plants compared with nongrafted plants. Root-knot severity was lower in plants grown in ASD-treated soils in high tunnels compared with plants grown in control soils, but grafting did not significantly decrease root-knot severity. However, soil treatment did not significantly affect yield, and grafting led to inconsistent impacts on yield.
Topics: Anaerobiosis; Ascomycota; Colletotrichum; Farms; Solanum lycopersicum; Plant Diseases; Soil; Verticillium
PubMed: 33174823
DOI: 10.1094/PHYTO-07-20-0288-R -
Medical Mycology Case Reports Sep 2023A mycotic infection manifesting as abdominal distension with free serous fluid accumulation in the coelomic cavity is documented in farmed rainbow trout. Histological...
A mycotic infection manifesting as abdominal distension with free serous fluid accumulation in the coelomic cavity is documented in farmed rainbow trout. Histological examination using PAS and silver staining revealed the presence of numerous fungal hyphae in the spleen and gastrointestinal wall. The isolated fungus was sterile and identified by using phylogenetic analysis based on four loci as . This is the first time this fungus has been reported as pathogen.
PubMed: 37274730
DOI: 10.1016/j.mmcr.2023.05.001 -
Medical Mycology Case Reports Dec 2019Dematiaceous fungi can cause subcutaneous phaeohyphomycosis, an uncommon fungal infection of the dermis and subcutaneous tissues. is an emerging organism that can...
Dematiaceous fungi can cause subcutaneous phaeohyphomycosis, an uncommon fungal infection of the dermis and subcutaneous tissues. is an emerging organism that can infect patients with subcutaneous phaeohyphomycosis, especially immunocompromised patients. The present case involved subcutaneous phaeohyphomycosis caused by in an 80-year-old Thai male with poorly controlled diabetes, for whom the lesion underwent spontaneous remission after his glycemic control was improved. Furthermore, cases of subcutaneous phaeohyphomycosis for the last 10 years were reviewed.
PubMed: 31890487
DOI: 10.1016/j.mmcr.2019.07.006