High Diversity of the Fungal Community Structure in Naturally-Occurring Ophiocordyceps sinensis

Abstract

Background Ophiocordyceps sinensis (syn. Cordyceps sinensis), which is a parasite of caterpillars and is endemic to alpine regions on the Tibetan Plateau, is one of the most valuable medicinal fungi in the world. “Natural O. sinensis specimens” harbor various other fungi. Several of these other fungi that have been isolated from natural O. sinensis specimens have similar chemical components and/or pharmaceutical effects as O. sinensis. Nevertheless, the mycobiota of natural O. sinensis specimens has not been investigated in detail.Methodology/Principal FindingsBased on the technique of PCR-single-strand conformation polymorphism (PCR-SSCP), the mycobiota of three different sections (stromata, sclerotia, and mycelial cortices) from natural O. sinensis specimens were investigated using both culture-dependent and -independent methods. For the culture-dependent method, 572 fungal strains were isolated, and 92 putative operational taxonomic units (OTUs) were identified from 226 sequenced strains with the threshold of 97%. For the culture-independent method, 490 fungal clones were identified from about 3000 clones of ITS fragments from the whole-community DNA; based on PCR-SSCP analyses, 266 of these clones were selected to be sequenced, and 118 putative OTUs were detected. The overwhelming majority of isolates/clones and OTUs were detected from mycelial cortices; only a few were detected from stromata and sclerotia. The most common OTUs detected with both methods belonged to Ascomycota; however, only 13 OTUs were detected simultaneously by both methods. Potential novel lineages were detected by each of the two methods.Conclusions/SignificanceA great number of fungal species present in the mycobiota of naturally-occurring O. sinensis specimens were detected, and many of them may represent undescribed lineages. That only a few of the same OTUs were detected by both methods indicated that different methods should be used. This study increased our understanding about the fungal community structure of this valuable medicinal herb.

Pyrroloquinoline Quinone Biosynthesis GenepqqC, a Novel Molecular Marker for Studying the Phylogeny and Diversity of Phosphate-Solubilizing Pseudomonads

“…The cultivation-dependent method probably detects bacteria that are present in low numbers and thus below the detection limit of the cultivation-independent method but that grow very well in liquid culture; these bacteria are selected for by the cultivation step. This finding is supported by other reports indicating that cultivation-dependent methods allow the identification of different genotypes compared to cultivation-independent methods (9,45). Bobwhite, the variety used in this study, seems to accumulate pseudomonads of subgroup 1g.…”

Density-weighted Algorithms for Similarity Computation and Cluster Tree Construction in the RAPD Analysis of Natural Cordyceps sinensis

“…We certainly hope that the complete genome information will be available in the near future for more component fungi of natural C. sinensis. The fungal genetic background is even more complex when nonculturable fungal species are taken into consideration [21,[24][25][26][27][28]47]. C. sinensis is therefore hypothesized as an "integrated microecosystem" [33].…”

Cordyceps industry in China

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