Nanopore sequencing of full rRNA operon improves resolution in mycobiome analysis and reveals high diversity in both human gut and environments.

High-throughput sequencing has substantially improved our understanding of fungal diversity. However, the short read (<500 bp) length of current second-generation sequencing approaches provides limited taxonomic and phylogenetic resolution for species discrimination. Longer sequences containing more information are highly desired to provide greater taxonomic resolution. Here, we amplified full-length rRNA operons (~5.5 kb) and established a corresponding fungal rRNA operon database for ONT sequences (FRODO), which contains ONT sequences representing eight phyla, 41 classes, 109 orders, 256 families, 524 genera and 1116 species. We also benchmarked the optimal method for sequence classification and determined that the RDP classifier based on our FRODO database was capable of improving the classification of ONT reads, with an average of 98%-99% reads correctly classified at the genus or species level. We investigated the applicability of our approach in three representative mycobiomes, namely, the soil, marine and human gut mycobiomes, and found that the gut contains the largest number of unknown species (over 90%), followed by the marine (42%) and soil (33.8%) mycobiomes. We also observed a distinct difference in the composition of the marine and soil mycobiomes, with the highest richness and diversity detected in soils. Overall, our study provides a systematic approach for mycobiome studies and revealed that the previous methods might have underestimated the diversity of mycobiome species. Future application of this method will lead to a better understanding of the taxonomic and functional diversity of fungi in environmental and health-related mycobiomes.

Channel Prediction-Based Security Authentication for Artificial Intelligence of Things.

The emerging physical-layer unclonable attribute-aided authentication (PLUA) schemes are capable of outperforming traditional isolated approaches, with the advantage of having reliable fingerprints. However, conventional PLUA methods face new challenges in artificial intelligence of things (AIoT) applications owing to their limited flexibility. These challenges arise from the distributed nature of AIoT devices and the involved information, as well as the requirement for short end-to-end latency. To address these challenges, we propose a security authentication scheme that utilizes intelligent prediction mechanisms to detect spoofing attack. Our approach is based on a dynamic authentication method using long short term memory (LSTM), where the edge computing node observes and predicts the time-varying channel information of access devices to detect clone nodes. Additionally, we introduce a Savitzky-Golay filter-assisted high order cumulant feature extraction model (SGF-HOCM) for preprocessing channel information. By utilizing future channel attributes instead of relying solely on previous channel information, our proposed approach enables authentication decisions. We have conducted extensive experiments in actual industrial environments to validate our prediction-based security strategy, which has achieved an accuracy of 97%.

Heterologous expression of a single fungal HR-PKS leads to the formation of diverse 2-alkenyl-tetrahydropyrans in model fungi.

2-Alkenyl-tetrahydropyrans belong to a rare class of natural products that exhibit broad antifungal activities. Their structural instability and rareness in nature have restrained their discovery and drug development. In this study, the heterologous expression of a single highly reducing polyketide synthase (HR-PKS, App1) from Trichoderma applanatum in Aspergillus nidulans leads to the formation of seven 2-alkenyl-tetrahydropyran derivatives including one known compound virensol C (1) and six new compounds (2-7). However, introducing App1 into Saccharomyces cerevisiae resulted in the identification of additional two 2-alkenyl-tetrahydropyrans lacking the hydroxyl or methoxyl group at the C-2 position (8 and 9). The structures of the isolated compounds were elucidated by extensive spectroscopic analysis using NMR and HR-ESI-MS.

Trichodermatides E and F from fungus Trichoderma applanatum.

Two new polyketide derivatives, trichodermatides E (1) and F (2), are unprecedented examples of a polyketide with 6/6/6/6 tetracyclic skeleton, together with five known analogs koninginin B (3), koninginin D (4), 7-O-methylkoninginin D (5), koninginins E and F (6-7), were isolated from the plant endophytic fungus Trichoderma applanatum. The structures of these two compounds were determined by NMR data and HR-ESI-MS analysis. The putative biosynthesis of compounds 1-7 was presented.

Botryane Sesquiterpenoids, Cyclopentadepsipeptides, Xanthones, and Trichothecenes from Trichoderma oligosporum.

Five new botryane sesquiterpenes (1: -5: ), one new cyclopentadepsipeptide (9: ), and two new xanthones (11:  - 12: ), together with 11 known compounds, were isolated from Trichoderma oligosporum. The structures of the new compounds were identified by comprehensive spectroscopic methods including nuclear magnetic resonance and mass spectrometry. The cytotoxicity of 1: -19: was evaluated against K562, A549, and ASPC cell lines. Compounds 5, 8, 11, 17: , and 18: showed cytotoxicity against the K562 cell line with more than 50% inhibition at 12.5 µM. As to A549 cell line, compound 8: showed the strongest cytotoxicity with approximately 50% inhibition at 25.0 µM. No compounds showed cytotoxicity against the ASPC cell line.

Three New Soil-inhabiting Species of Trichoderma in the Stromaticum Clade with Test of Their Antagonism to Pathogens.

Trichoderma is a dominant component of the soil mycoflora. During the field investigations of northern, central, and southwestern China, three new species in the Stromaticum clade were encountered from soil, and named as T. hebeiense, T. sichuanense, and T. verticillatum. Their phylogenetic positions were determined by analyses of the combined two genes: partial sequences of translation elongation factor 1-alpha and the second largest RNA polymerase subunit-encoding genes. Distinctions between the new species and their close relatives were discussed. Trichoderma hebeiense appeared as a separate terminal branch. The species is distinctive by its oblong conidia and aggregated pustules in culture. Trichoderma sichuanense features in concentric colony and produces numerous clean exudates on aerial mycelium in culture. Trichoderma verticillatum is characterized by its verticillium-like synanamorph and production of abundant chlamydospores. In vitro antagonism towards the new species was tested by dual culture technique.

Richard Paul Korf (1925-2016).

"With poetry, the tune is in the words themselves-and once you begin to hear it, it will stay with you." Richard P. Korf, notes to his narration of John Brown's Body.

Three New Species of Penicillium from East and Northeast China.

Penicillium species are ubiquitous in the environment and are of substantial importance, especially in industrial and medical aspects. During our investigation of the biodiversity of Penicillium, three new species were discovered in soil samples collected from East and Northeast China. They were determined as new to science based on morphological comparisons and phylogenetic analyses, and were found to belong to the subgenus Penicillium section Robsamsonia and subgenus Aspergilloides sections Aspergilloides and Citrina. Descriptions and illustrations of these species are provided, and their geographic distributions are also discussed.

Disulfide bridge-targeted metabolome mining unravels an antiparkinsonian peptide.

Peptides are a particular molecule class with inherent attributes of some small-molecule drugs and macromolecular biologics, thereby inspiring continuous searches for peptides with therapeutic and/or agrochemical potentials. However, the success rate is decreasing, presumably because many interesting but less-abundant peptides are so scarce or labile that they are likely 'overlooked' during the characterization effort. Here, we present the biochemical characterization and druggability improvement of an unprecedented minor fungal RiPP (ribosomally synthesized and post-translationally modified peptide), named acalitide, by taking the relevant advantages of metabolomics approach and disulfide-bridged substructure which is more frequently imprinted in the marketed peptide drug molecules. Acalitide is biosynthetically unique in the macrotricyclization via two disulfide bridges and a protease (AcaB)-catalyzed lactamization of AcaA, an unprecedented precursor peptide. Such a biosynthetic logic was successfully re-edited for its sample supply renewal to facilitate the identification of the in vitro and in vivo antiparkinsonian efficacy of acalitide which was further confirmed safe and rendered brain-targetable by the liposome encapsulation strategy. Taken together, the work updates the mining strategy and biosynthetic complexity of RiPPs to unravel an antiparkinsonian drug candidate valuable for combating Parkinson's disease that is globally prevailing in an alarming manner.

New Species of Neocosmospora (Ascomycota) from China as Evidenced by Morphological and Molecular Data.

Species of Neocosmospora are commonly found in soil, plant debris, and living woody or herbaceous substrates and occasionally found in water and air. Some species are reported as saprobes, endophytes, opportunistic pathogens of plants and animals, or producers of bioactive natural products, cytotoxic compounds, and industrial enzymes. To reveal the species diversity of Neocosmospora, specimens from different provinces of China were investigated. Five new species, Neocosmospora anhuiensis, N. aurantia, N. dimorpha, N. galbana, and N. maoershanica, were introduced based on morphological characteristics and DNA sequence analyses of combined calmodulin (CAM), the internal transcribed spacer (ITS), the second largest subunit of RNA polymerase II (RPB2), and the translation elongation factor 1-α (TEF1) regions. Differences between these new species and their close relatives are compared in detail.

Three New Species of Fusicolla (Hypocreales) from China.

To explore the species diversity of the genus Fusicolla, specimens from Henan, Hubei and Jiangsu Provinces in China are examined, and three undescribed taxa are encountered. The morphological characteristics and DNA sequence analyses of the combined acl1, ITS, LSU, rpb2 and tub2 regions support their placement in Fusicolla and their recognition as new species. Fusicolla aeria sp. nov. is distinguished by the formation of abundant aerial mycelia on PDA, falcate, (1-)3-septate macroconidia 16-35 × 1.5-2.8 µm and subcylindrical, aseptate microconidia 7.5-13 × 0.8-1.1 µm. Fusicolla coralloidea sp. nov. has a coralloid colony on PDA, falcate, 2-5-septate macroconidia 38-70 × 2-4.5 µm and rod-shaped to ellipisoidal, aseptate microconidia 2-7 × 1-1.9 µm. Fusicolla filiformis sp. nov. is characterized by filiform, 2-6-septate macroconidia 28-58 × 1.5-2.3 µm and lacking microconidia. Morphological differences between these novel species and their close relatives are compared in detail. The previously recorded species of the genus in China are listed and a key to these taxa is provided.

Species Diversity of Helvella lacunosa Clade (Pezizales, Ascomycota) in China and Description of Sixteen New Species.

Helvella lacunosa and its allies are widely distributed in the Northern Hemisphere and perform important functions in ecosystems. A comprehensive study on 101 collections of Helvella lacunosa, including those deposited in four Chinese fungaria or collected recently from 10 provinces, was conducted based on morphological and molecular characteristics. Phylogenies of "Helvella lacunosa clade" inferred from Hsp90, ITS, LSU, and TEF were reconstructed with 49 lineages recognized, of which 25 lineages occurred in China, and each represented an individual species. Sixteen new species were determined with detailed descriptions and illustrations. Two new Chinese records were reported. Species concepts and their distinctions in macro- and micro-features were discussed.

Species Diversity of Penicillium in Southwest China with Discovery of Forty-Three New Species.

Penicillium species are ubiquitous in all kinds of environments, and they are of industrial, agricultural and clinical importance. In this study, soil fungal diversity in Southwestern China was investigated, and that of Penicillium turned out to be unexpectedly high. The survey included a total of 179 cultures of the genus isolated from 33 soil samples. Three-locus phylogenetic analyses and morphological comparisons were carried out. The examinations revealed that they belonged to two subgenera (Aspergilloides and Penicillium), 11 sections (Aspergilloides, Canescentia, Citrina, Exilicaulis, Fasciculata, Gracilenta, Lanata-Divaricata, Penicillium, Ramosum, Robsamsonia, and Sclerotiorum), 25 series, and 74 species. Forty-three species were discovered as new to science, and a new series, Simianshanica, was established in sect. Aspergilloides. Additionally, 11 species were recorded for the first time in China. Species isolation frequency and distribution of the group were also discussed.

Bacillus velezensis BV01 Has Broad-Spectrum Biocontrol Potential and the Ability to Promote Plant Growth.

To evaluate the potential of a bacterial strain as a fungal disease control agent and plant growth promoter, its inhibitory effects on phytopathogens such as Bipolaris sorokiniana, Botrytis cinerea, Colletotrichum capsici, Fusarium graminearum, F. oxysporum, Neocosmospora rubicola, Rhizoctonia solani, and Verticillium dahliae were investigated. The results showed that the inhibitory rates in dual-culture and sterile filtrate assays against these eight phytopathogens ranged from 57% to 83% and from 36% to 92%. The strain was identified as Bacillus velezensis based on morphological and physiological characterization as well as phylogenetic analyses of 16S rRNA and the gyrase subunit A protein (gyrA) regions. The results demonstrated that B. velezensis was able to produce fungal cell-wall-degrading enzymes, namely, protease, cellulase, and ß-1,3-glucanase, and the growth-promotion substances indole-3-acetic acid (IAA) and siderophore. Furthermore, B. velezensis BV01 had significant control effects on wheat root rot and pepper Fusarium wilt in a greenhouse. Potted growth-promotion experiments displayed that BV01 significantly increased the height, stem diameter, and aboveground fresh and dry weights of wheat and pepper. The results imply that B. velezensis BV01, a broad-spectrum biocontrol bacterium, is worth further investigation regarding its practical applications in agriculture.

Spirocitrinols A and B, citrinin derivatives with a spiro[chromane-2,3'-isochromane] skeleton from Penicillium citrinum.

Spirocitrinols A (1) and B (2), two new citrinin-derived metabolites possessing a spiro[chromane-2,3'-isochromane] skeleton, were isolated from cultures of Penicillium citrinum. Their structures were elucidated primarily by NMR experiments. The absolute configurations of 1 and 2 were assigned by electronic circular dichroism calculations. Compound 2 is the first naturally occurring trimeric citrinin derivative with a spiro[chromane-2,3'-isochromane] core. Compound 1 showed modest cytotoxicity against A549 human tumor cells.

Seven New Species of Eurotiales (Ascomycota) Isolated from Tidal Flat Sediments in China.

Tidal flats have been reported to contain many microorganisms and play a critical role in maintaining biodiversity. In surveys of filamentous fungi from tidal flat sediments in China, seven new species of Eurotiales were discovered and described. Morphological characteristics and DNA sequence analyses of combined datasets of the BenA, CaM, and RPB2 regions support their placements and recognition as new species. Aspergillus liaoningensis sp. nov. and A. plumeriae sp. nov. belong to sections Candidi and Flavipedes of subgenus Circumdati, and A. subinflatus sp. nov. is a member of section Cremei of subgenus Cremei. Penicillium danzhouense sp. nov., P. tenue sp. nov., and P. zhanjiangense sp. nov. are attributed to sections Exilicaulis and Lanata-Divaricata of subgenus Aspergilloides. Talaromyces virens sp. nov. is in section Talaromyces. Detailed descriptions and illustrations of these novel taxa are provided. Their differences from close relatives were compared and discussed.

Lachnochromonin, a fungal metabolite from Lachnum virgineum, inhibits cell growth and promotes apoptosis in tumor cells through JAK/STAT3 signaling.

Natural compounds that interfere with tumor cell growth have potential to be used as therapeutic agents to treat cancers. Lachnochromonin (p71) is a small molecule isolated from Lachnum virgineum. Here, we reported the effect of p71 on human tumor cells, especially on breast cancer MCF-7 cells. We found that p71 significantly suppresses cell growth and induces apoptosis. The luciferase results demonstrated that p71 specifically attenuates the activation of JAK/STAT3 signaling. Biochemical analysis revealed that p71 blocks the phosphorylation of STAT3 tyrosine 705 and serine 727, resulting in down-regulation of c-Myc and Cyclin D1 expression level. Importantly, p71 inhibited cell growth, colony-formation, and migration through affecting STAT3 activity. These results implied that p71 may be used as a therapeutic agent against breast cancer.

Phylogeny and Taxonomic Revision of the Family Discinaceae (Pezizales, Ascomycota).

Species of Discinaceae are common macrofungi with a worldwide distribution. Some of them are commercially consumed, while a few others are reported as poisonous. Two genera were accepted in the family: the epigeous Gyromitra with discoid, cerebriform to saddle-shaped ascomata and the hypogeous Hydnotrya with globose or tuberous ascomata. However, due to discrepancies in their ecological behaviors, a comprehensive investigation of their relationship was not thoroughly explored. In this study, phylogenies of Discinaceae were reconstructed using sequence analyses of combined and separate three gene partitions (internal transcribed spacer [ITS], large subunit ribosomal DNA [LSU], and translation elongation factor [TEF]) with a matrix containing 116 samples. As a result, the taxonomy of the family was renewed. Eight genera were recognized: two of them (Gyromitra and Hydnotrya) were retained, three (Discina, Paradiscina, and Pseudorhizina) were revived, and three (Paragyromitra, Pseudodiscina, and Pseudoverpa) were newly established. Nine new combinations were made in four genera. Two new species in Paragyromitra and Pseudodiscina and an un-named taxon of Discina were described and illustrated in detail based on the materials collected from China. Furthermore, a key to the genera of the family was also provided. IMPORTANCE Taxonomy of the fungal family Discinaceae (Pezizales, Ascomycota) was significantly renewed on the basis of sequence analyses of internal transcribed spacer (ITS), large subunit ribosomal DNA (LSU), and translation elongation factor (TEF). Eight genera were accepted, including three new genera; two new species were described; and nine new combinations were made. A key to the accepted genera of the family is provided. The aim of this study is to deepen the understanding of the phylogenetic relationships among genera of the group, as well as the associated generic concepts.

MAPK Cascades Mediating Biocontrol Activity of Trichoderma brevicrassum Strain TC967.

Trichoderma brevicrassum strain TC967 is a novel biological control agent (BCA) against the plant pathogen Rhizoctonia solani and promotes plant growth. Mitogen-activated protein kinase (MAPK) cascades are involved in a variety of physiological functions of Trichoderma, but functions of each MAPK in regulating biocontrol have not been characterized in a single Trichoderma strain. In this study, we assembled and annotated the genome of strain TC967 and identified its three MAPK gene sequences. Functions of Fus3-, Slt2-, and Hog1-MAPK in strain TC967 were dissected. All three MAPKs were involved in hyphal growth. Hog1-MAPK was essential for conidiation and tolerance to saline/osmotic stress. Both Fus3- and Slt2-MAPK deletion mutants reduced cell-wall integrity (CWI) and increased the activities of chitinase and protease. The growth of Rhizoctoniasolani was further inhibited by volatile organic compounds (VOCs) and secondary metabolites produced by Fus3- and Slt2-MAPK deletion mutants, respectively. Biocontrol assays demonstrated that Fus3- and Slt2-MAPK deletion mutants were considerably more effective in disease control than the wild-type strain. RNA-seq analysis revealed that MAPK collectively played a major role in regulating biocontrol-related gene expressions, including the genes in charge of secondary metabolism, fungal cell wall-degrading enzymes (FCWDEs), and small secreted cysteine-rich proteins (SSCPs).

New Species of Talaromyces (Trichocomaceae, Eurotiales) from Southwestern China.

Species of Talaromyces are cosmopolitan and ubiquitous, and some are of industrial and medicinal importance. Species of Talaromyces have been successively reported in China. During our examinations of samples collected from southwestern China, two new species belonging to Talaromyces sect. Talaromyces were further discovered based on phylogenetic analyses and morphological comparisons. Talaromyces ginkgonis sp. nov., isolated from a partially colonized fruit of Ginkgo biloba, differs from closely-related fungi in the combination of conidia ellipsoidal, smooth and 3.5-4 × 2-3 µm, no growth on CYA at 37 °C and sequence divergences; T. shilinensis sp. nov. is distinguished from its related allies in the combination of smooth conidia, colonies 10-11 mm diameter on CYA at 25 °C and sequence differences. Detailed descriptions and illustrations of the new taxa are given.