Project description:Hirsutella (Ophiocordycipitaceae: Hypocreales) is a genus of insect, mite, and nematode pathogens with an asexual morph, which generally produce a mucilaginous cluster of one or several conidia on phialides that are basally subulate and taper to a fine neck. The generic name Hirsutella has been proposed for suppression in favour of Ophiocordyceps as a consequence of the ending of dual nomenclature for different morphs of pleomorphic fungi in 2011. Though the generic name is well established, geographically dispersed, and speciose, exceptionally few sequences are available in online databases. We examined 46 isolates of 23 Hirsutella species from the USA, curated by the USDA-ARS Collection of Entomopathogenic Fungal Cultures (ARSEF Culture Collection), that previously had not been molecularly characterized and produced a phylogeny of these organisms; we included previously published Hirsutella and Ophiocordyceps taxa. In producing the largest phylogeny of Hirsutella isolates so far, we provide: (1) context for discussing previously-hypothesized relationships; (2) evidence for revisions as taxonomic transitions move forward; and (3) available molecular data to be incorporated into further evolutionary studies of Ophiocordycipitaceae.
Project description:Ophiocordyceps sinensis has been used as a traditional medicine or healthy food in China for thousands of years. Hirsutella sinensis was reported as the only correct anamorph of O. sinensis. It is reported that the laboratory-grown H. sinensis mycelium has similar clinical efficacy and less associated toxicity compared to the wild O. sinensis. The research of the H. sinensis is becoming more and more important and urgent. To gain deeper insight into the biological and pharmacological mechanisms, we sequenced the genome of H. sinensis. The genome of H. sinensis (102.72 Mb) was obtained for the first time, with?>?99% coverage. 10,200 protein-encoding genes were predicted based on the genome sequence. A detailed secondary metabolism analysis and structure verification of the main ingredients were performed, and the biosynthesis pathways of seven ingredients (mannitol, cordycepin, purine nucleotides, pyrimidine nucleotides, unsaturated fatty acid, cordyceps polysaccharide and sphingolipid) were predicted and drawn. Furthermore, infection process and mechanism of H. sinensis were studied and elaborated in this article. The enzymes involved in the infection mechanism were also predicted, cloned and expressed to verify the mechanism. The genes and proteins were predicted and annotated based on the genome sequence. The pathways of several active components in H. sinensis were predicted and key enzymes were confirmed. The work presented here would improve the understanding of the genetic basis of this organism, and contribute to further research, production and application of H. sinensis.
Project description:To enhance nucleoside production in Hirsutella sinensis, the biosynthetic pathways of purine and pyrimidine nucleosides were constructed and verified. The differential expression analysis showed that purine nucleoside phosphorylase, inosine monophosphate dehydrogenase, and guanosine monophosphate synthase genes involved in purine nucleotide biosynthesis were significantly upregulated 16.56-fold, 8-fold, and 5.43-fold, respectively. Moreover, dihydroorotate dehydrogenase, uridine nucleosidase, uridine/cytidine monophosphate kinase, and inosine triphosphate pyrophosphatase genes participating in pyrimidine nucleoside biosynthesis were upregulated 4.53-fold, 10.63-fold, 4.26-fold, and 5.98-fold, respectively. To enhance the nucleoside production, precursors for synthesis of nucleosides were added based on the analysis of biosynthetic pathways. Uridine and cytidine contents, respectively, reached 5.04?mg/g and 3.54?mg/g when adding 2?mg/mL of ribose, resulting in an increase of 28.6% and 296% compared with the control, respectively. Meanwhile, uridine and cytidine contents, respectively, reached 10.83?mg/g 2.12?mg/g when adding 0.3?mg/mL of uracil, leading to an increase of 176.3% and 137.1%, respectively. This report indicated that fermentation regulation was an effective way to enhance the nucleoside production in H. sinensis based on biosynthetic pathway analysis.
Project description:In this study, we report the complete mitochondrial genome of Hirsutella rhossiliensis (Ophiocordycipitaceae, Hypocreales, Ascomycota). We construct the mitochondrial DNA genome organization of 62?483?bp in length of H. rhossiliensis by using the whole-genome resequencing method. Conserved genes including the large and small rRNA subunits, 26 tRNA and 14 protein-coding genes are identified. These protein-coding genes utilize ATG, GTG or TTG as initiation codons and TAA or TAG as termination codons. Moreover, we detect 10 group I introns and one unclassified intron in six genes (rnl, cob, cox1, cox3, nad1 and nad5) encoding ORFs of ribosomal protein S3 and GIY-YIG/LAGLIDADG endonucleases or hypothetical proteins. This mitochondrial genome will be useful in understanding the distribution and genetic diversity of this species.
Project description:Hirsutella sinensis mycelium (HSM), the anamorph of Cordyceps sinensis, is a traditional Chinese medicine that has been shown to possess various pharmacological properties. We previously reported that this fungus suppresses interleukin-1? and IL-18 secretion by inhibiting both canonical and non-canonical inflammasomes in human macrophages. However, whether HSM may be used to prevent lung fibrosis and the mechanism underlying this activity remain unclear. Our results show that pretreatment with HSM inhibits TGF-?1-induced expression of fibronectin and ?-SMA in lung fibroblasts. HSM also restores superoxide dismutase expression in TGF-?1-treated lung fibroblasts and inhibits reactive oxygen species production in lung epithelial cells. Furthermore, HSM pretreatment markedly reduces bleomycin-induced lung injury and fibrosis in mice. Accordingly, HSM reduces inflammatory cell accumulation in bronchoalveolar lavage fluid and proinflammatory cytokines levels in lung tissues. The HSM extract also significantly reduces TGF-?1 in lung tissues, and this effect is accompanied by decreased collagen 3?1 and ?-SMA levels. Moreover, HSM reduces expression of the NLRP3 inflammasome and P2X7R in lung tissues, whereas it enhances expression of superoxide dismutase. These findings suggest that HSM may be used for the treatment of pulmonary inflammation and fibrosis.