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Journal of Fungi (Basel, Switzerland) May 2023(J. U. Santos) is an endemic plant species in Morro do Urucum in the Pantanal wetland (Brazil). is used for the restoration of areas impacted by iron mining...
(J. U. Santos) is an endemic plant species in Morro do Urucum in the Pantanal wetland (Brazil). is used for the restoration of areas impacted by iron mining activities. This study evaluates the diversity (composition, value and abundance) of endophytic fungal communities, considering parts of the plant and soil condition. The leaves and roots of were collected from native vegetation areas (NVA) and recovery areas (RCA) in Morro do Urucum. Illumina sequencing technology was used to investigate variation in endophytic fungal biodiversity. The operational taxonomic units detected in NVA ranged from 183 to 263 (leaf) and 115 to 285 (root), while RCA samples ranged from 200 to 282 (leaf) and 156 to 348 (root). Ascomycota phylum was the most common species among all plant samples. The most significant classes identified were Lecanoromycetes and Dothideomycetes that differed significantly ( ≤ 0.05) according to their plant hosts and soil stress. The relative abundance of (Sordariomycetes class) and (Lecanoromycetes class) genera was influenced by the iron mining activities according to the leaf samples analysed. However, the abundance and wealth of endophytic fungal communities in from RCA were evidence that could explain their high resilience to environmental disturbances and the source-sink dynamics of fungal propagules.
PubMed: 37367568
DOI: 10.3390/jof9060632 -
Journal of Fungi (Basel, Switzerland) May 2023Leaf litter is an essential functional aspect of forest ecosystems, acting as a source of organic matter, a protective layer in forest soils, and a nurturing habitat for...
Leaf litter is an essential functional aspect of forest ecosystems, acting as a source of organic matter, a protective layer in forest soils, and a nurturing habitat for micro- and macro-organisms. Through their successional occurrence, litter-inhabiting microfungi play a key role in litter decomposition and nutrient recycling. Despite their importance in terrestrial ecosystems and their abundance and diversity, information on the taxonomy, diversity, and host preference of these decomposer taxa is scarce. This study aims to clarify the taxonomy and phylogeny of four saprobic fungal taxa inhabiting leaf litter. Leaf litter samples were collected from Doi Inthanon National Park in Chiang Mai, northern Thailand. Fungal isolates were characterized based on morphology and molecular phylogeny of the nuclear ribosomal DNA (ITS, LSU) and protein-coding genes (, , ). One novel saprobic species, , and two new host records, and , are introduced. The newly described taxa are compared with similar species, and comprehensive descriptions, micrographs, and phylogenetic trees are provided.
PubMed: 37367561
DOI: 10.3390/jof9060625 -
Journal of Fungi (Basel, Switzerland) May 2023Bayberry twig blight caused by the ascomycete fungus is a devastating disease threatening worldwide bayberry production. However, the molecular basis underlying the...
Bayberry twig blight caused by the ascomycete fungus is a devastating disease threatening worldwide bayberry production. However, the molecular basis underlying the pathogenesis of is largely unknown. Here, we identified and functionally characterized the MAP kinase PvMk1 in through genetic and cellular biochemical approaches. Our analysis reveals a central role of PvMk1 in regulating virulence on bayberry. We demonstrate that PvMk1 is involved in hyphal development, conidiation, melanin biosynthesis, and cell wall stress responses. Notably, PvMk1 regulates autophagy and is essential for hyphal growth under nitrogen-depleting conditions. These findings suggest the multifaceted role of PvMk1 in regulating development and virulence. More remarkably, this evidence of virulence-involved cellular processes regulated by PvMk1 has paved a fundamental way for further understanding the impact of pathogenesis on bayberry.
PubMed: 37367542
DOI: 10.3390/jof9060606 -
The Journal of General and Applied... Feb 2024Six aromatic secondary metabolites, pestalone (1), emodin (2), phomopsilactone (3), pestalachlorides B (4), C (5), and D (6), were isolated from Pestalotiopsis sp....
Six aromatic secondary metabolites, pestalone (1), emodin (2), phomopsilactone (3), pestalachlorides B (4), C (5), and D (6), were isolated from Pestalotiopsis sp. FKR-0115, a filamentous fungus collected from white moulds growing on dead branches in Minami Daito Island. The efficacy of these secondary metabolites against methicillin-resistant Staphylococcus aureus (MRSA) with and without meropenem (β-lactam antibiotic) was evaluated using the paper disc method and broth microdilution method. The chemical structures of the isolated compounds (1-6) were characterised using spectroscopic methods, including nuclear magnetic resonance and mass spectrometry. All six isolated compounds exhibited synergistic activity with meropenem against MRSA. Among the six secondary metabolites, pestalone (1) overcame bacterial resistance in MRSA to the greatest extent.
Topics: Methicillin-Resistant Staphylococcus aureus; Anti-Bacterial Agents; Meropenem; Pestalotiopsis; beta-Lactams; beta-Lactam Resistance; Microbial Sensitivity Tests; Benzophenones
PubMed: 37302827
DOI: 10.2323/jgam.2023.06.001 -
Plant Disease Jun 2023(Burkill) F. H. Chen ex C. Y. Wu & K.M. Feng is a Chinese herbal medicinal plant for treating diseases of the central nervous system and cardiovascular system, widely...
(Burkill) F. H. Chen ex C. Y. Wu & K.M. Feng is a Chinese herbal medicinal plant for treating diseases of the central nervous system and cardiovascular system, widely used as a medicine and health-care product. In May 2022, leaf blight disease was found on leaves of 1-year-old in the plantings (27.904°N, 112.918°E) of Xiangtan City (Hunan) with an area of 10 m. Over 400 plants were investigated, up to 25% of the plants were symptomatic. From the margin of the leaf, the initial symptoms of water-soaked chlorosis and following dry yellow with slight shrinkage appeared. Later, leaf shrinkage became serious and chlorosis enlarged gradually, leading to leaf death and abscission. To identify the causal agent, 20 leaf lesions (4 mm) collected from 20 individual 1-year-old plants were sterilized with 75% ethanol for 10 s, 5% NaOCl for 10 s, rinsed in sterilized water three times, placed on potato dextrose agar (PDA) with lactic acid (0.125%) for inhibition the growth of bacteria, and incubated at 28°C for 7 days (Fang, 1998). Five isolates were obtained from 20 leaf lesions of different plants with the isolation rate of 25% and purified by single sporing, which have similar colony and conidia morphology characteristics. One isolate PB2-a was selected randomly for further identification. Colonies of PB2-a on PDA were white with cottony mycelium, developing concentric circles (top view) or light yellow (back view). Conidia (23.1 ± 2.1 × 5.7 ± 0.8 µm, n=30)were fusiform, straight or slightly curved and contained conic basal cell, three light brown median cells and hyaline conic apical cell with appendages. The rDNA internal transcribed spacer (ITS), the translation elongation factor 1-alpha (), and the β-tubulin (TUB2) genes were amplified from genomic DNA of PB2-a using primers ITS4/ITS5 (White et al. 1990), EF1-526F/EF1-1567R (Maharachchikumbura et al. 2012), and Bt2a/Bt2b (Glass and Donaldson, 1995; O'Donnell and Cigelnik, 1997), respectively. BLAST search of sequenced ITS (OP615100), (OP681464) and TUB2 (OP681465) exhibited > 99% identity with the type strain of OP068 (JQ845947, JQ845946 and JQ845945). Phylogenetic tree of the concatenated sequences was constructed based on the maximum-likelihood method using MEGA-X. Isolate PB2-a was identified as based on morphological and molecular data (Maharachchikumbura et al. 2011; Qi et al. 2022). PB2-a was tested for pathogenicity three times to confirm Koch's postulates. Twenty healthy leaves on 20 1-year-old plants were punctured with sterile needles and inoculated with 50 µl of conidial suspension (1×10 conidia/ml). The controls were inoculated with sterile water. All plants were placed in a greenhouse at 25°C under 80% relative humidity. After 7 days, all inoculated leaves developed leaf blight symptoms identical to those described above, whereas the control plants kept healthy. were reisolated from infected leaves, and identical to those of the originals based on the colony characteristics and the sequenced data of ITS, and TUB2. was reported as a pathogen of leaf blight on (Xu et al. 2022). To our knowledge, this is the first report of causing leaf blight on in Hunan, China. Leaf blight is one of the destructive diseases in production, identification of the pathogen will be useful to develop effective disease management and protect , a medical plant with economic value.
PubMed: 37294156
DOI: 10.1094/PDIS-04-23-0681-PDN -
PLoS Pathogens Jun 2023Satellites associated with plant or animal viruses have been largely detected and characterized, while those from mycoviruses together with their roles remain far less...
Satellites associated with plant or animal viruses have been largely detected and characterized, while those from mycoviruses together with their roles remain far less determined. Three dsRNA segments (dsRNA 1 to 3 termed according to their decreasing sizes) were identified in a strain of phytopathogenic fungus Pestalotiopsis fici AH1-1 isolated from a tea leaf. The complete sequences of dsRNAs 1 to 3, with the sizes of 10316, 5511, and 631 bp, were determined by random cloning together with a RACE protocol. Sequence analyses support that dsRNA1 is a genome of a novel hypovirus belonging to genus Alphahypovirus of the family Hypoviridae, tentatively named Pestalotiopsis fici hypovirus 1 (PfHV1); dsRNA2 is a defective RNA (D-RNA) generating from dsRNA1 with septal deletions; and dsRNA3 is the satellite component of PfHV1 since it could be co-precipitated with other dsRNA components in the same sucrose fraction by ultra-centrifuge, suggesting that it is encapsulated together with PfHV1 genomic dsRNAs. Moreover, dsRNA3 shares an identical stretch (170 bp) with dsRNAs 1 and 2 at their 5' termini and the remaining are heterogenous, which is distinct from a typical satellite that generally has very little or no sequence similarity with helper viruses. More importantly, dsRNA3 lacks a substantial open reading frame (ORF) and a poly (A) tail, which is unlike the known satellite RNAs of hypoviruses, as well as unlike those in association with Totiviridae and Partitiviridae since the latters are encapsidated in coat proteins. As up-regulated expression of RNA3, dsRNA1 was significantly down-regulated, suggesting that dsRNA3 negatively regulates the expression of dsRNA1, whereas dsRNAs 1 to 3 have no obvious impact on the biological traits of the host fungus including morphologies and virulence. This study indicates that PfHV1 dsRNA3 is a special type of satellite-like nucleic acid that has substantial sequence homology with the host viral genome without encapsidation in a coat protein, which broadens the definition of fungal satellite.
Topics: RNA, Satellite; RNA Viruses; Pestalotiopsis; RNA, Double-Stranded; Phylogeny; RNA, Viral; Genome, Viral; Fungal Viruses; Open Reading Frames
PubMed: 37285391
DOI: 10.1371/journal.ppat.1010889 -
Phytochemistry Sep 2023Biotransformation of toxic components by plant endophytes has become an effective method to reduce the toxicity of target compounds and discover lead compounds. In this...
Biotransformation of toxic components by plant endophytes has become an effective method to reduce the toxicity of target compounds and discover lead compounds. In this context, an endophytic fungus, Pestalotiopsis sp. LGT-1, from Tripterygium wilfordii Hook F. (TwHF), was used to reduce the toxicity of celastrol which is also produced by TwHF and is considered an attractive molecule with a variety of biological activities. Seven celastrol derivatives (1-7) were isolated from the coculture fermentation broth of LGT-1 and celastrol. Their structures were elucidated by spectroscopic data analysis including 1D and 2D NMR, as well as HRESIMS. Their absolute configurations were determined by analysis of NOESY, ECD data and NMR calculations. In cell proliferation experiments, the toxicity of seven compounds was 10.11- to 1.24-fold lower in normal cells than the prototype compound celastrol. These derivatives serve as potential candidates for future pharmaceutical applications.
Topics: Pestalotiopsis; Molecular Structure; Magnetic Resonance Spectroscopy; Biotransformation; Tripterygium
PubMed: 37279870
DOI: 10.1016/j.phytochem.2023.113750 -
Journal of Fungi (Basel, Switzerland) May 2023Black spot needle blight is a serious conifer disease of var. occurring in Northeast China, which is usually caused by the plant pathogenic fungus . From the diseased...
Black spot needle blight is a serious conifer disease of var. occurring in Northeast China, which is usually caused by the plant pathogenic fungus . From the diseased pine needles collected in Honghuaerji, the strain YJ-3 was isolated and identified as the phytopathogen, and its culture characteristics were studied. Then, we generated a highly contiguous 48.36-Mbp genome assembly (N50 = 6.62 Mbp) of the strain YJ-3 by combining the PacBio RS II Single Molecule Real Time (SMRT) and Illumina HiSeq X Ten sequencing platforms. The results showed that a total of 13,667 protein-coding genes were predicted and annotated using multiple bioinformatics databases. The genome assembly and annotation resource reported here will be useful for the study of fungal infection mechanisms and pathogen-host interaction.
PubMed: 37233276
DOI: 10.3390/jof9050564 -
BMC Microbiology May 2023To explore the community composition and diversity of the endophytic fungi in Taxillus chinensis, samples of the parasites growing on seven different hosts, Morus alba,...
BACKGROUND
To explore the community composition and diversity of the endophytic fungi in Taxillus chinensis, samples of the parasites growing on seven different hosts, Morus alba, Prunus salicina, Phellodendron chinense, Bauhinia purpurea, Dalbergia odorifera, Diospyros kaki and Dimocarpus longan, were isolated. The strains were identified by their morphological characteristics and their internal transcribed spacer (ITS) sequences.
RESULTS
150 different endophytic fungi were isolated from the haustorial roots of the seven hosts with a total isolation rate of 61.24%. These endophytic fungi were found to belong to 1 phylum, 2 classes, 7 orders, 9 families, 11 genera and 8 species. Among of them, Pestalotiopsis, Neopestalotiopsis and Diaporthe were the dominant genera, accounting for 26.67, 17.33 and 31.33% of the total number of strains, respectively. Diversity and similarity analyses showed that the endophytic fungi isolated from D. longan (H'=1.60) had the highest diversity index. The highest richness indexes were found in M. alba and D. odorifera (both 2.23). The evenness index of D. longan was the highest (0.82). The similarity coefficient of D. odorifera was the most similar to D. longan and M. alba (33.33%), while the similarity coefficient of P. chinense was the lowest (7.69%) with M. alba and D. odorifera. Nine strains showed antimicrobial activities. Among them, Pestalotiopsis sp., N. parvum and H. investiens showed significant antifungal activity against three fungal phytopathogens of medicinal plants. At the same time, the crude extracts from the metabolites of the three endophytic fungi had strong inhibitory effects on the three pathogens. Pestalotiopsis sp., N. parvum and H. investiens had the strongest inhibitory effects of S. cucurbitacearum, with inhibitory rates of 100%, 100% and 81.51%, respectively. In addition, N. parvum had a strong inhibitory effect on D. glomerata and C. cassicola, with inhibitory rates of 82.35% and 72.80%, respectively.
CONCLUSIONS
These results indicate that the species composition and diversity of endophytic fungi in the branches of T. chinensis were varied in the different hosts and showed good antimicrobial potential in the control of plant pathogens.
Topics: Humans; Fungi; Loranthaceae; Endophytes; Biodiversity; Anti-Infective Agents; Phylogeny
PubMed: 37173641
DOI: 10.1186/s12866-023-02878-x -
Plant Disease May 2023Weizhi Xun and Changwang Wu contributed equally to this work In October 2020, bayberry (Myrica rubra (Lour.) S. et Zucc.) leaves that beginning to wither were collected...
Weizhi Xun and Changwang Wu contributed equally to this work In October 2020, bayberry (Myrica rubra (Lour.) S. et Zucc.) leaves that beginning to wither were collected in Wencheng County (N27°50', E120°03'). In the county, 4,120 ha of bayberry were planted, of which 58% were affected by the disease, and the severity of leaf disease per plant was 5 to25%. Bayberry leaves leaves were intensely green at first, then gradually turned yellow and brown,and completely withered. The leaves did not fall off at the beginning of the symptoms, but did fall after 1 to 2 months. To identify the pathogen, 50 diseased leaves with typical symptoms were collected from 10 diseased trees. Leaves with necrotic-tissue were firstly washed with sterilized water, and then tissue at the disease-/ healthy-tissuejunction removed with sterile surgical scissors. The tissues were soaked in 75% ethanol for 30 s, followed by 5% sodium hypochlorite solution for 3 to 4 min, rinsed with sterilized water 4 times, and placed on sterilized filter paper. The tissue was placed on PDA medium and cultured in an incubator at 25℃ (Nouri et al. 2019). After the colonies grew around the tissue, mycelia with the same morphology was selected and placed on fresh PDA. A pure culture of the pathogen was obtained after repeating the last process several times. The isolatedcolonies were white, with a round edge and a light-yellow back. Conidia were straight or slightly curved, with 3 to 4 septations. The internal transcribed spacer (ITS) regin translation elongation factor 1-α gene (TEF1-α), and beta-tubulin gene (β-TUB)(Chaiwan et al. 2020; Li et al. 2021; Chen et al. 2020; Chen et al. 2018) of the two strains were amplified and sequenced, and the sequences were uploaded to Gen bank (GenBank accession number.ACCC 35162: ITS OP891011, TEF1-α OP903533, β-TUB OP903531; ACCC 35163: ITS OP891012, β-TUB OP903534, TEF1-α OP903532). BLAST alignment indicated that the ITS sequence of strain ACCC 35162 had 100% identity with NR_147549.1, the TEF sequence had 100% identity with MT552449.1, and the TUB sequence had 99.87% identity with KX895323.1; the ITS sequence of strain ACCC 35163 had 100% identity with NR_147549.1, the TEF sequence had 100% identity with MT552449.1, and the TUB sequence had 99.86% identity with KX895323.1. A Phylogenetic tree using maximum likelihood/rapid bootstrapping run on XSEDE based on the above three sequences inferred that the two strains were identical to P. kenyana (Miller et al. 2010). The strain was preserved in the Agricultural Culture Collection of China (Preservation numbers: ACCC 35162, ACCC 35163). Following Koch's rule, six healthy plants leaves were inoculated with conidial suspensions (106 conidia mL-1) and mycelial plugs (5 mm),and then placed in an artificial climate chamber (25℃, 90% humidity, 16-h light), sterile PDA and sterile water were used as blank controls. The same treatment was applied to fresh bayberry leaves under laboratory conditions, and brown spots were observed after three days. There were no symptoms in the control group. The experimental symptoms were similar to those in the field. Using the previous method, the same fungus was reisolated from the diseased leaves and again identified as P. kenyana. As far as we know, this is the first report causing disease on P. kenyana infecting bayberry in China, this disease seriously affected the yield and quality of bayberry and caused economic losses to farmers.
PubMed: 37172979
DOI: 10.1094/PDIS-03-23-0450-PDN