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Stipa purpurea is among constructive endemic species in the alpine steppe on the Qinghai-Xizang Plateau. To reveal the fungal community structure and diversity in the rhizosphere and roots of this important grass and to analyze the potential influence of different habitats on the structure of fungal communities, we explored the root endophyte and the directly associated rhizosphere communities of S. purpurea by using internal transcribed spacer rRNA cloning and sequencing methods. We found that the roots of S. purpurea are associated with a diverse consortium of Basidiomycota (59.8%) and Ascomycota (38.5%). Most fungi obtained from rhizosphere soil in S. purpurea have been identified as Ascomycetes, while the high proportion detected in roots were basidiomycetous endophytes. The species richness, diversity, and evenness of fungal assemblages were higher in roots than in the rhizosphere soil. Fungi inhabiting the rhizosphere and roots of S. purpurea are significantly different, and the rhizosphere and endophyte communities are largely independent with little overlap in the dominant phyla or operational taxonomic units. Taken together, these results suggested that a wide variety of fungal communities are associated with the roots and rhizosphere soil of S. purpurea and that the fungal assemblages are strongly influenced by different habitats. [ABSTRACT FROM AUTHOR]

This study is the first to describe the composition and characteristics of culturable bacterial isolates from the rhizosphere and bulk soil of the medicinal plant Stellera chamaejasme L. at different growth stages. Using a cultivation-dependent approach, a total of 148 isolates showing different phenotypic properties were obtained from the rhizosphere and bulk soil. Firmicutes and Actinobacteria were the major bacterial groups in both the rhizosphere and bulk soil at all 4 growth stages of S. chamaejasme. The diversity of the bacterial community in the rhizosphere was higher than that in bulk soil in flowering and fruiting stages. The abundance of bacterial communities in the rhizosphere changed with the growth stages and had a major shift at the fruiting stage. Dynamic changes of bacterial abundance and many bacterial groups in the rhizosphere were similar to those in bulk soil. Furthermore, most bacterial isolates exhibited single or multiple biochemical activities associated with S. chamaejasme growth, which revealed that bacteria with multiple physiological functions were abundant and widespread in the rhizosphere and bulk soil. These results are essential ( i) for understanding the ecological roles of bacteria in the rhizosphere and bulk soil and ( ii) as a foundation for further evaluating their efficacy as effective S. chamaejasme growth-promoting rhizobacteria. [ABSTRACT FROM AUTHOR]

To clarify the relationship between neutral lipid content and cordycepin accumulation in Cordycepsmilitaris, mutants were generated from mixed spores of two C. militaris strains with varying cordycepin-producing capacities. Fifteen stable mutants producing from 0.001 to 2.363 mg/mL cordycepin were finally selected. The relative fluorescence intensities of the 15 mutants, two C. militaris strains and an Aspergillus nidulans strain at different concentrations of lyophilized mycelium powder were then investigated using the Nile red method. The mutant CM1-1-1 with the highest relative fluorescence intensity among the eighteen strains was selected for optimizing the Nile red method. Relative fluorescence intensity was linearly correlated with cordycepin concentration in liquid broth (R2 = 0.9514) and in lyophilized mycelium powder (R2 = 0.9378) for the 18 cordycepin-producing strains under identical culture conditions and with cordycepin concentration in liquid broth (R2 = 0.9727) and in lyophilized mycelium powder (R2 = 0.9613) for CM1-1-1 under eight different sets of conditions. In addition, the cordycepin content in lyophilized mycelium powder measured by the Nile red method was linearly correlated with that determined by an HPLC method (R2 = 0.9627). In conclusion, neutral lipids in lipid droplets are required during cordycepin accumulation; these neutral lipids are potential biomarkers of cordycepin biosynthesis. [ABSTRACT FROM AUTHOR]

The Hequ Tibetan MastiffCanis lupus familiaris(Carnivora: Canidae) is a primitive breed of large dogs native to the northeastern Qinghai-Tibetan Plateau of China. In this study, its complete mitochondrial genome sequence has been assembled and characterized using high-throughput Illumina sequencing technology. The circular genome is 16 730 bp in length, and possesses all genomic components as typically found in most other metazoan mitogenomes. The gene arrangement is identical to those of most other vertebrates. Except forND4Lwith GTG as its start codon, all the other PCGs are initiated with an ATR (ATA/ATG) codon. Three distinct stop codons are employed, i.e. AGA forCYTB, TAA forATP6, ATP8, COX1, COX2, ND1, ND4L, ND5andND6, and an incomplete stop codon T forCOX3, ND2, ND3andND4. The nucleotide composition is asymmetric (31.6% A, 25.5% C, 14.2% G and 28.7% T) with an overall A + T content of 60.3%. These data would contribute to our better understanding its evolutionary history. [ABSTRACT FROM AUTHOR]

Cordycepin (3′-deoxyadenosine), a cytotoxic nucleoside analogue found in Cordyceps militaris, has attracted much attention due to its therapeutic potential and biological value. Cordycepin interacts with multiple medicinal targets associated with cancer, tumor, inflammation, oxidant, polyadenylation of mRNA, etc. The investigation of the medicinal drug actions supports the discovery of novel targets and the development of new drugs to enhance the therapeutic potency and reduce toxicity. Cordycepin may be of great value owing to its medicinal potential as an external drug, such as in cosmeceutical, traumatic, antalgic and muscle strain applications. In addition, the biological application of cordycepin, for example, as a ligand, has been used to uncover molecular structures. Notably, studies that investigated the metabolic mechanisms of cordycepin-producing fungi have yielded significant information related to the biosynthesis of high levels of cordycepin. Here, we summarized the medicinal targets, biological applications, cytotoxicity, delivery carriers, stability, and pros/cons of cordycepin in clinical applications, as well as described the metabolic mechanisms of cordycepin in cordycepin-producing fungi. We posit that new approaches, including single-cell analysis, have the potential to enhance medicinal potency and unravel all facets of metabolic mechanisms of cordycepin in Cordyceps militaris. [ABSTRACT FROM AUTHOR]