Amanitin is the most lethal mushroom toxin in mushroom poisoning cases in China. The main mechanism of amanitin poisoning is the interaction between amanitin and eukaryotic RNA polymerase Ⅱ and inhibiting the formation of mRNA. In this paper, the research progress concerning interaction between α-amanitin and eukaryotic polymerase Ⅱ was reviewed. The research history of 110 years (1907-) of interaction between α-amanitin and eukaryotic polymerase Ⅱ is divided into eight stages, including early research on amanitins, advancement of chemical structure analysis, toxicology research, structure-activity relationship research, biochemistry research, molecular biology research, structural biology research, and drug development and evaluation. The corresponding discussion on research processes and important results is given. Hopefully this paper will bring new thinking to the field of clinical toxicology.
The antifungal drugs acting on cell wall are a kind of the safest antifungal drugs. Because they have high efficiency and low toxicity as compared with any other antifungal drugs due to that the fungal cells have unique wall structure, which are distinct from human cells. This article reviews the antifungal drugs that act on the cell wall, and introduces preparations inhibiting glucan synthase, inhibiting chitin synthase and inhibiting glycosylphosphatidylinositol-anchored protein according to the different functional mechanisms and antifungal targets, and summarizes the antifungal mechanism, treatment spectrum and the research progress of the antifungal drugs as mentioned above, providing an overview references for the development of related drugs and the application in clinic.
Coprinoid fungi include the species of Coprinellus, Coprinopsis, Parasola, Tulosesus and Narcissea, belonging to Psathyrellaceae with the exception of Coprinus in Agaricaceae. Based on the specimens and literature records, there are 57 species of coprinoid fungi hitherto known from China, including 9 of Coprinellus, 10 of Tulosesus, 3 of Narcissea, 25 of Coprinopsis, 8 of Parasola, and 2 of Coprinus. Here, 1 new combination, Narcissea ephemeroides, and 11 new Chinese records, Coprinellus ellisii, Coprinellus saccharinus, Coprinopsis acuminata, Coprinopsis afronivea, Coprinopsis bellula, Coprinopsis mitraespora, Coprinopsis narcotica, Coprinopsis pachyderma, Coprinopsis pseudonivea, Parasola schroeteri and Parasola setulosa, were presented. Phylogenetic analysis based on multigene alignment of ITS and LSU sequence datasets was used to investigate the relationships of the fungi. The new combination and newly recorded species were confirmed by the phylogeny result. Illustrations and photographs of these species are provided. Besides, the keys to known species of coprinoid fungi from China were provided.
Fungi are one of the three main organisms in eukaryote (Fungi, Plantae and Animalia). Fungi with large fruiting bodies visible to the naked eyes and hand-pickable were commonly known as mushrooms and toadstools. Taxonomically, most of the macrofungi are of Basidiomycota and a few Ascomycota. In the past decades, development of molecular analyses and phylogeny promote great progress in fungal taxonomy and the evolutionary relationships of fungal taxa are more perfectly known than before. Thus, the taxonomic systems of macrofungi are changed accordingly, greatly, and updated constantly. However, these changes make difficulties for public users who are interested in macrofungi. To meet the public demands, we revised the taxonomic system of macrofungi based on our recent results of research on molecular phylogeny and taxonomy, and estabilish the Macrofungi Classification System and Information Platform. This platform is supported from State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Herbarium Mycologicum Academiae Sinicae, Institute of Microbiology, Chinese Academy of Sciences, Mycological Society of China, and Fungarium Union of China. This platform provides a comprehensive taxonomic system and information on macrofungi, and will be updated periodically with domestic and international mycologist’s cooperation, to meet the requirements of related researchers.
Floccularia luteovirens, an ectomycorrhizal fungus in grassland, is highly valuable to ecology and economy. Herbage rhizosphere microorganisms can promote the growth of ectomycorrhizal fungi, mycorrhizal formation and the formation of fruiting bodies. In this study, high-throughput sequencing technology was applied to analyze the microbial community composition in fruiting body-emersed and surrounding soil of F. luteovirens in Tibet, attempting to explore beneficial microorganism resources for promoting the fungal growth. The results showed that bacteria in the soil of F. luteovirens habitat could be referred to 17 phyla, 22 classes, 116 orders, 161 families and 227 genera, and the dominant phyla Acidobacteria, Proteobacteria, Bacteroidetes and Verrucomicrobia accounted for 81.75%. Fungi in the habitat soil were referred to 5 phyla, 17 classes, 34 orders, 55 families and 61 genera, and dominant phyla Ascomycota and Basidiomycota accounted for 80.89%. The bacteria potentially promoting the growth of F. luteovirens were Flavisolibacter, Flavobacterium, Gemmatimonas, Haliangium, Segetibacter and Sphingomonas; the fungi potentially promoting the growth of F. luteovirens were Clitopilus, Cortinarius, Mortierella and Mucor. The mechanisms of soil microorganisms promoting the growth and reproduction of F. luteovirens need further study.
As one of the infectious diseases threatening human health, fungal infection is an universal problem. The present study sought to examine how ginkgolide B and C impacts mitochondrial structure and overall functionality in Aspergillus niger. Ginkgolide with different concentrations were added to spore suspension of A. niger, then the mycelia were collected, and the antifungal effect of ginkgolides on A. niger was investigated. Observation by transmission electron microscopy showed that ginkgolide B caused significant vacuolization of mitochondria and destruction of matrix structure, resulting in the decrease of activities of succinate dehydrogenase and malate dehydrogenase, the key enzymes in mitochondrial tricarboxylic acid cycle, the reduction of mitochondrial membrane potential, and marked elevation of malondialdehyde levels. The results preliminarily revealed that ginkgolide damaged the integrity of mitochondrial membrane and mitochondrial structure, and thereby further damaged mitochondrial function in a dose-dependent manner, so as to achieve the effect against A. niger. The anti-A. niger effect of ginkgolide B was significantly higher than that of ginkgolide C.
Anthracnose is one of the most important diseases occurring on Camellia oleifera. The dominant pathogen causing the disease is Colletotrichum fructicola which is common in C. oleifera producing areas all over the country. Previous study recognized that the histone acetyltransferase CfGcn5 regulated growth, development and pathogenicity of C. fructicola, but the functions of histone deacetylases remain unknown. In this study, the reverse genetics method was adopted to comparatively analyze the biological phenotypes of wide-type, CfSNT2 gene knockout mutant and its complementary strains of C. fructicola. It was found that the CfSNT2 gene knockout mutant showed decrement of mycelial growth rate, and conidial and appressorial formation rate, and abnormal response to cell wall integrity stress agents, resulting in decrease of pathogenicity to C. oleifera. The findings show that CfSnt2 regulates the mycelial growth, conidial and appressorial formation, tolerance to cell wall integrity stress agents, and pathogenicity of C. fructicola.
Codon preference and characteristics of the gene highly expressed during developments of Flammulina filiformis were explored. Genome and transcriptome data of F. filiformis were used to analyze the codon preference and its influencing factors, and the functional annotation and cis-element analysis of high expression genes were carried out. The results showed that high expression genes of F. filiformis showed strong codon preference, and most preferred codons ended with cytosine (C). The optimal codons of six amino acids in the high expression genes were conservative. In the evolutionary process, codon preference of high expression genes of F. filiformis was greatly affected by natural selection pressure. Functional annotation classification shows that high expression genes are mostly ribosomal pathway related genes in relation to protein translation and biosynthesis. The cis-element analysis showed that MeJA response element, ABA response element, light response element and MYB transcription factor binding element were mostly presented in the promoter region of high expression genes. The results provide theoretical basis and ideas for improving heterologous expression efficiency and strong promoter mining of F. filiformis.
The terrestrial orchid Gymnadenia conopsea with important medicinal value has been listed in the National Key Protected Wild Plant (Category Ⅱ). At present, G. conopsea could not be cultivated artificially, however, seed symbiotic germination has been successfully achieved. In order to determine whether other indigenous fungi were also involved in seed germination process besides the initial germination-promoting fungi, isolation of symbiotic fungi from protocorms formed by germination-promoting fungi under natural conditions were performed on six common media PDA (potato dextrose agar medium), MMN (modified Melin-Norkrans medium), FIM (fungal isolation medium), MEA (malt extract ager medium), CAM (carrot agar medium) and CMA (corn meal agar medium), and the relative abundance were compared. In total, 75 fungal isolates were obtained from the 6 media, and the number of fungal isolates obtained from MMN, CAM, PDA, FIM, MEA and CMA was 20, 16, 15, 11, 8 and 5, respectively. The results of fungal diversity analysis showed that fungal diversity index (Chao 1, Shannon-Wiener, and Simpson diversity index) of the isolates from MMN medium was the highest, and that from CAM and PDA medium was less, while that from CMA medium was the lowest. In short, MMN is the most effective, followed by CAM and PDA, and FIM and MEA media have little effect, while CMA is the worst. Our results provide reference for the isolation of symbiotic fungi from protocorms of other orchids. The fungal strains obtained in this study hopefully could be further used for research purpose and development of functional microbial agents.
Light plays an important role in the growth and morphogenesis of Flammulina filiformis. Cryptochrome is one of the main receptors that respond to light signals. In this study, the gene and protein structure of FL19 cryptochrome gene Ffcry from F. filiformis were identified. The promoter of Ffcry was predicted to contain three light response elements, and the promoter of FL19 cryptochrome gene Ffcry from F. filiformis was identified to be cis-regulatory element. Furthermore, the expression patterns of Ffcry genes under different light conditions were systematically studied. The results showed that the expression of Ffcry gene under blue light was significantly higher than that under dark and other light with different wavelengths. The expression of Ffcry was the highest when the luminous flux was 10 μmol/(m2·s), and the expression of Ffcry increased gradually after 20 min of blue light irradiation, and became stable after 180 min. The Ffcry gene were expressed most in the young cap, secondly in the elongate cap and the mature cap. The molecular function of cryptochrome and the light morphogenesis of F. filiformis need further study.
The truffle, Mattirolomyces terfezioides, is a hypogeous ascomycete and was found recently under Prunus persica trees in Hebei Province, China. The morphology was described based on its fresh ascomata and its possible host plants were identified. The volatile organic compounds (VOCs) of M. terfezioides were analyzed and compared with those of members of Tuber. Mattirolomyces terfezioides is characterized by its 8-spore asci and globose spores ornamented with blunt spines sometimes connected at base to form an irregular alveolate reticulum at maturity. The roots of P. persica colonized by M. terfezioides grew weakly and no typical ectomycorrhizal structure was found but similar characters as endophytic fungi in previous study was observed. M. terfezioides couldn’t grow on PDA medium, implying it is potentially mycorrhizal. The VOCs isolated were characterized by GC-MS and totally 68 compounds were detected in the fresh ascocarps. The main compounds were 3-octanone (37.19%), 1-octene-3-ol (22.67%) and 3-octanol (12.53%). This is the first data of VOCs of this species and valuable for M. terfezioides utilization in future.
This study aims at exploring the effects of Sanghuangporus vaninii water extract on immune function of immunocompromised mice caused by cyclophosphamide. S. vaninii water extract was obtained by using ultrasound and boiling water extracting methods. Injection of cyclophosphamide was conducted to cause immunocompromise of mice. The immune function of immunocompromised mice was evaluated by measuring spleen and thymus index, serum immunoglobulin and cytokine, splenic lymphocyte proliferation and carbon clearance. The results showed that compared with the model group, the immune organ index, serum immunoglobulin content, cytokine level, splenic lymphocyte proliferation degree, phagocytosis rate and phagocytosis index of macrophages, and ear swelling degree of mice were increased without exception in mice administered with water extract of S. vaninii. HE staining of spleen also showed S. vaninii decoction could improve the pathological state of spleen caused by cyclophosphamide. The facts proved that the water extract of S. vaninii had a good immune protection effect on immunosuppressive mice induced by cyclophosphamide, and clinical application of S. vaninii decoction seems expectable.
Principal constituents of Gomphus purpuraceus collected from Three Gorges region of Hubei Province were isolated and identified and their antiproliferative activity was evaluated. Six compounds from ethyl acetate extract of fruiting body of G. purpuraceus were isolated by solvent extraction, column chromatography and semi-preparative high performance liquid chromatography. Their structures were determined by NMR and MS as (22E,24R)-ergosta-5,7,22- triene-3β-ol (1), 3β,5α-dihydroxy-(22E,24R)-ergosta-7,22-dien-6-one (2), (22E, 24R)-ergosta-7,22-dien-3β,5α,6β- triol (3), methyl 1H-indole-3-carboxylate (4), 4,4-dimethyl-1,7-heptanedioic acid (5) and (8E,10E)-12-oxo-octadeca-8,10-dienoic acid (6), of which compound 1 was the major component with relative content of 23.8% analyzed by HPLC with a UV detector at 254 nm. The antiproliferative activity aginst cancer cells of these compounds were evaluated by crystal violet method and compound 3 showed weak antiproliferative activity against MCF-7, PANC-1 and MDA-MB-231 cells. The chemical constituents of G. purpuraceus are reported for the first time and their utilization in the field of health needs further exploration.
The chemical constituents of fruiting body of Stropharia rugosoannulata was extracted by dichloromethane, ethyl acetate (EtOAc), n-butanol and water. Diphenyl trinitrophenyl hydrazine free radical (DPPH), hydroxyl free radical and reducing power methods were used to analyze the antioxidant activities of the four extracts in vitro. The EtOAc extract showed the strongest antioxidant activity as compared with other extracts. Chemical constituents of the EtOAc extract were analyzed using ultra-high performance liquid chromatography tandem triple TOF-MS (UPLC-Triple-TOF/MS). Nine compounds were identified as nucleoside analogues, which displayed good antioxidant activities. The results provide a reference for further development of S. rugosoannulata.
Five new Chinese records, Cosmospora khandalensis, C. viridescens, Neocosmospora protoensiformis, Pseudocosmospora rogersonii and Tumenectria laetidisca, are reported based on the specimens collected from Anhui, Henan, Hubei, Yunnan and Tibet. Their descriptions and illustrations are provided based on observations of the Chinese materials.
