RESUMO
Medicinal phytochemicals, such as artemisinin and taxol, have impacted the world, and hypericin might do so if its availability issue could be addressed. Hypericin is the hallmark component of Saint John's wort (Hypericum perforatum L.), an approved depression alleviator documented in the US, European, and British pharmacopoeias with its additional effectiveness against diverse cancers and viruses. However, the academia-to-industry transition of hypericin remain hampered by its low in planta abundance, unfeasible bulk chemical synthesis, and unclear biosynthetic mechanism. Here, we present a strategy consisting of the hypericin-structure-centered modification and reorganization of microbial biosynthetic steps in the repurposed cells that have been tamed to enable the designed consecutive reactions to afford hypericin (43.1â mg L-1 ), without acquiring its biosynthetic knowledge in native plants. The study provides a synthetic biology route to hypericin and establishes a platform for biosustainable access to medicinal phytochemicals.
Assuntos
Antracenos/metabolismo , Fungos/metabolismo , Hypericum/química , Perileno/análogos & derivados , Compostos Fitoquímicos/biossíntese , Antracenos/química , Fungos/química , Estrutura Molecular , Perileno/química , Perileno/metabolismo , Compostos Fitoquímicos/químicaRESUMO
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.
Assuntos
Policetídeo SintasesRESUMO
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.
Assuntos
Policetídeos/química , Policetídeos/farmacologia , Trichoderma/química , Antifúngicos/química , Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Estrutura Molecular , Resultados Negativos , Espectrometria de Massas por Ionização por ElectrosprayRESUMO
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.
Assuntos
Antibiose , Filogenia , Microbiologia do Solo , Trichoderma/isolamento & purificação , Trichoderma/fisiologia , China , RNA Polimerases Dirigidas por DNA/genética , Técnicas Microbiológicas , Microscopia , Micélio/crescimento & desenvolvimento , Fator 1 de Elongação de Peptídeos/genética , Análise de Sequência de DNA , Esporos Fúngicos/citologia , Trichoderma/classificação , Trichoderma/citologiaRESUMO
"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.
RESUMO
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.
RESUMO
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.
RESUMO
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.
RESUMO
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.
RESUMO
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.
RESUMO
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.
RESUMO
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.
Assuntos
Ascomicetos , Filogenia , Ascomicetos/genética , DNA Ribossômico/genética , Análise de Sequência de DNA , Fatores de Alongamento de Peptídeos/genética , DNA Fúngico/genéticaRESUMO
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).
Assuntos
Hypocreales , Trichoderma , Hypocreales/metabolismo , Sistema de Sinalização das MAP Quinases , Proteínas Quinases Ativadas por Mitógeno/metabolismoRESUMO
We describe two new species of Pezicula (Dermateaceae, Ascomycota), P. ellipsoides and P. fusispora, which are discovered in China. Pezicula ellipsoides sp. nov. is distinct in producing 2-3 stipitate apothecia on a basal stroma with a light yellow hymenium, broadly ellipsoid 0-1(-2)-septate ascospores, and divergent DNA sequence data. Pezicula fusispora sp. nov. is characterized by sessile apothecia, 0.3-0.8 mm in diam, a yellowish hymenium, J+ asci 135-170 × 15-21 µm, multiseptate ascospores, 33-48 × 7-10.3 µm, and growing on rotten bamboo. In addition, Pezicula acericola and P. carpinea are reported for the first time from China, and 11 Pezicula species previously reported from China are reviewed and briefly noted, of which one was a misidentified species. Phylogenetic analyses inferred from ITS nrDNA sequences confirm the placement of P. ellipsoides and P. cinnamomea in the genus Pezicula.
RESUMO
Three new species of Clonostachys are introduced based on specimens collected from China. Clonostachys chongqingensis sp. nov. is distinguished by pale yellow to pale orange-yellow perithecia with a very low papilla, clavate to subcylindrical asci possessing ellipsoidal to elongate-ellipsoidal spinulose ascospores 13-16 × 4.5-5.5 µm; it has acremonium- to verticillium-like conidiophores and ellipsoidal to rod-shaped conidia. Clonostachys leptoderma sp. nov. has pinkish-white subglobose to globose perithecia on a well-developed stroma and with a thin perithecial wall, clavate to subcylindrical asci with ellipsoidal to elongate-ellipsoidal spinulose ascospores 7.5-11 × 2.5-3.5 µm; it produces verticillium-like conidiophores and ellipsoidal to subellipsoidal conidia. Clonostachys oligospora sp. nov. features solitary to gregarious perithecia with a papilla, clavate asci containing 6-8 smooth-walled ascospores 9-17 × 3-5.5 µm; it forms verticillium-like conidiophores and sparse, subfusiform conidia. The morphological characteristics and phylogenetic analyses of combined nuclear ribosomal DNA ITS1-5.8S-ITS2 and beta-tubulin sequences support their placement in Clonostachys and their classification as new to science. Distinctions between the novel taxa and their close relatives are compared herein.
RESUMO
Species of Nectriaceae commonly occur on living and decaying woody substrates, soil, fruitbodies of other fungi, and insects. Some of them are reported as endophytes, opportunistic pathogens of crops and humans, or producers of mycotoxins. To explore the species diversity of the family, specimens from different regions of China were collected and examined. Four novel taxa of Penicillifer, Pseudocosmospora, and Thelonectria were introduced on the basis of morphological characteristics and DNA sequence analyses of combined datasets of the act, ITS, LSU, rpb1, rpb2, tef1, and tub2 regions. Differences between the new species and their close relatives were compared and discussed.
RESUMO
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.
RESUMO
Aspergillus species are cosmopolitan and ubiquitous, closely related to human daily life. They are also of food, industrial and medical importance. From the examination of cultures isolated from soil samples collected on tropical islands of China, four new species of the genus were discovered based on phylogenetic analyses and morphological comparisons. Aspergillus xishaensis sp. nov. and A. neoterreus sp. nov. belong to sections Flavipedes and Terrei of subgenus Circumdati, and A. hainanicus sp. nov. and A. qilianyuensis sp. nov. are in sections Cavernicolarum and Nidulantes of subgenus Nidulantes. To accommodate A. hainanicus, a new series Hainanici was proposed. Detailed descriptions and illustrations of the new taxa were provided.
RESUMO
Studies on the genus Acervus from China are reviewed briefly. Six of the seven known species of the genus are currently recorded in this country. Acervus beijingense and A. changchunense are described as new based on morphological features and molecular data, and A. flavidus with minor emendation is added to the Chinese fungus flora. Phylogenetic relationships among four of the seven species of the genus are investigated based on the 28S rDNA sequence analysis. Species of the genus formed a single clade with high bootstrap support. The sequences of A. epispartius forma epispartius and that of A. flavidus obtained from materials in different geographical regions together formed a group with 100% bootstrap support. Ascospore size and shape are important criteria in the taxonomy of the genus and are phylogenetically informative. A dichotomous key to all described species of the genus is provided.
Assuntos
Ascomicetos/classificação , Ascomicetos/isolamento & purificação , Ascomicetos/genética , China , DNA Fúngico/genética , DNA Ribossômico/genética , Dados de Sequência Molecular , FilogeniaRESUMO
Chitinases are involved in multiple aspects of fungal life cycle, such as cell wall remodelling, chitin degradation and mycoparasitism lifestyle. To improve our knowledge of the chitinase molecular evolution of Ascomycota, the gene family of 72 representatives of this phylum was identified and subjected to phylogenetic, evolution trajectory and selective pressure analyses. Phylogenetic analysis showed that the chitinase gene family size and enzyme types varied significantly, along with species evolution, especially for groups B and C. In addition, two new subgroups, C3 and C4, are recognized in group C chitinases. Random birth and death testing indicated that gene expansion and contraction occurred in most of the taxa, particularly for species in the order Hypocreales (class Sordariomycetes). From an enzyme function point of view, we speculate that group A chitinases are mainly involved in species growth and development, while the expansion of genes in group B chitinases is related to fungal mycoparasitic and entomopathogenic abilities, and, to a certain extent, the expansion of genes in group C chitinases seems to be correlated with the host range broadening of some plant-pathogenic fungi in Sordariomycetes. Further selection pressure testing revealed that chitinases and the related amino acid sites were under positive selection in the evolutionary history, especially at the nodes sharing common ancestors and the terminal branches of Hypocreales. These results give a reasonable explanation for the size and function differences of chitinase genes among ascomycetes, and provide a scientific basis for understanding the evolutionary trajectories of chitinases, particularly that towards a mycoparasitic lifestyle.