Fungal Cordycepin Biosynthesis Is Coupled with the Production of the Safeguard Molecule Pentostatin

Cordyceps militaris: A novel mushroom platform for metabolic engineering

Cordyceps militaris, widely recognized as a medicinal and edible mushroom in East Asia, contains a variety of bioactive compounds, including cordycepin (COR), pentostatin (PTN) and other high-value compounds. This review explores the potential of developing C. militaris as a cell factory for the production of high-value chemicals and nutrients. This review comprehensively summarizes the fermentation advantages, metabolic networks, expression elements, and genome editing tools specific to C. militaris and discusses the challenges and barriers to further research on C. militaris across various fields, including computational biology, existing DNA elements, and genome editing approaches. This review aims to describe specific and promising opportunities for the in-depth study and development of C. militaris as a new chassis cell. Additionally, to increase the practicability of this review, examples of the construction of cell factories are provided, and promising strategies for synthetic biology development are illustrated.

Bioactive compounds from Cordyceps and their therapeutic potential

The Clavicipitaceae family's largest and most diverse genus is Cordyceps. They are most abundant and diverse in humid temperate and tropical forests and have a wide distribution in: Europe, North America, and East and Southeast Asian countries, particularly: Bhutan, China, Japan, Nepal, Korea, Thailand, Vietnam, Tibet, and the Himalayan region of India, and Sikkim. It is a well-known parasitic fungus that feeds on insects and other arthropods belonging to 10 different orders. Over 200 bioactive metabolites, that include: nucleotides and nucleosides, polysaccharides, proteins, polypeptides, amino acids, sterols, and fatty acids, among others have been extracted from Cordyceps spp. demonstrating the phytochemical richness of this genus. These components have been associated with a variety of pharmacological effects, including: anti-microbial, anti-apoptotic, anti-cancer, anti-inflammatory, antioxidant, and immunomodulatory activities. In this paper, the bioactivity of various classes of metabolites produced by Cordyceps spp., and their therapeutic properties have been reviewed in an attempt to update the existing literature. Furthermore, one of its nucleoside and a key bioactive compound, cordycepin has been critically elaborated with regard to its biosynthesis pathway and the recently proposed protector-protégé mechanism as well as various biological and pharmacological effects, such as: suppression of purine and nucleic acid biosynthesis, induction of apoptosis, and cell cycle regulation with their mechanism of action. This review provides current knowledge on the bioactive potential of Cordyceps spp.

Glucopeptide Superstructure Hydrogel Promotes Surgical Wound Healing Following Neoadjuvant Radiotherapy by Producing NO and Anticellular Senescence

Neoadjuvant radiotherapy, a preoperative intervention regimen for reducing the stage of primary tumors and surgical margins, has gained increasing attention in the past decade. However, radiation-induced skin damage during neoadjuvant radiotherapy exacerbates surgical injury, remarkably increasing the risk of refractory wounds and compromising the therapeutic effects. Radiation impedes wound healing by increasing the production of reactive oxygen species and inducing cell apoptosis and senescence. Here, a self-assembling peptide (R-peptide) and hyaluronic-acid (HA)-based and cordycepin-loaded superstructure hydrogel is prepared for surgical incision healing after neoadjuvant radiotherapy. Results show that i) R-peptide coassembles with HA to form biomimetic fiber bundle microstructure, in which R-peptide drives the assembly of single fiber through π-π stacking and other forces and HA, as a single fiber adhesive, facilitates bunching through electrostatic interactions. ii) The biomimetic superstructure contributes to the adhesion and proliferation of cells in the surgical wound. iii) Aldehyde-modified HA provides dynamic covalent binding sites for cordycepin to achieve responsive release, inhibiting radiation-induced cellular senescence. iv) Arginine in the peptides provides antioxidant capacity and a substrate for the endogenous production of nitric oxide to promote wound healing and angiogenesis of surgical wounds after neoadjuvant radiotherapy.

A novel complementary pathway of cordycepin biosynthesis in Cordyceps militaris

We determined whether there exists a complementary pathway of cordycepin biosynthesis in wild-type Cordyceps militaris, high-cordycepin-producing strain C. militaris GYS60, and low-cordycepin-producing strain C. militaris GYS80. Differentially expressed genes were identified from the transcriptomes of the three strains. Compared with C. militaris, in GYS60 and GYS80, we identified 145 and 470 upregulated and 96 and 594 downregulated genes. Compared with GYS80, in GYS60, we identified 306 upregulated and 207 downregulated genes. Gene Ontology analysis revealed that upregulated genes were mostly involved in detoxification, antioxidant, and molecular transducer in GYS60. By Clusters of Orthologous Groups of Proteins and Kyoto Encyclopedia of Genes and Genomes analyses, eight genes were significantly upregulated: five genes related to purine metabolism, one to ATP production, one to secondary metabolite transport, and one to RNA degradation. In GYS60, cordycepin was significantly increased by upregulation of ATP production, which promoted 3',5'-cyclic AMP production. Cyclic AMP accelerated 3'-AMP accumulation, and cordycepin continued to be synthesized and exported. We verified the novel complementary pathway by adding the precursor adenosine and analyzing the expression of four key genes involved in the main pathway of cordycepin biosynthesis. Adenosine addition increased cordycepin production by 51.2% and 10.1%, respectively, in C. militaris and GYS60. Four genes in the main pathway in GYS60 were not upregulated.

A novel betapartitivirus isolated from Cordyceps militaris, an edible-medicinal mushroom

In this study, we identified a novel partitivirus, named "Cordyceps militaris partitivirus 1" (CmPV1), in Cordyceps militaris strain RCEF7506. The complete genome of CmPV1 comprises two segments, dsRNA1 and dsRNA2, each encoding a single protein. dsRNA1 (2,206 bp) encodes an RNA-dependent RNA polymerase (RdRp), and dsRNA2 (2,256 bp) encodes a coat protein (CP). Sequence analysis revealed that dsRNA1 has the highest similarity to that of Bipolaris maydis partitivirus 2 (BmPV2), whereas dsRNA2 shows the highest similarity to human blood-associated partitivirus (HuBPV). Phylogenetic analysis based on RdRp sequences suggests that CmPV1 is a new member of the genus Betapartitivirus of the family Partitiviridae. This is the first documentation of a betapartitivirus infecting the entomopathogenic fungus C. militaris.

New insights into the chemistry and anticancer activity of Ophiocordyceps xuefengensis

Ophiocordyceps xuefengensis (O. xuefengensis), the sister taxon of Ophiocordyceps sinensis (O. sinensis), is consumed as a "tonic food" due to its health benefits. However, little is known regarding the chemistry and bioactivity of O. xuefengensis. In this study, we characterized 80 indole-based alkaloids in the ethyl acetate fraction of O. xuefengensis by high performance liquid chromatography-quadrupole time of flight mass spectrometry (HPLC-Q-TOF-MS/MS), of which 54 indole-based alkaloids were identified as possibly new compounds. Furthermore, 29 of these compounds were established as potential anti-cancer compounds by ligand fishing combined with HPLC-Q-TOF-MS/MS. Moreover, molecular docking identified the NH- and OH- groups of these compounds as the key active groups. The present study has expanded the knowledge on the characteristic indole-based alkaloids and anti-cancer activity of O. xuefengensis.

The insect microbiome is a vast source of bioactive small molecules

Covering: September 1964 to June 2023Bacteria and fungi living in symbiosis with insects have been studied over the last sixty years and found to be important sources of bioactive natural products. Not only classic producers of secondary metabolites such as Streptomyces and other members of the phylum Actinobacteria but also numerous bacteria from the phyla Proteobacteria and Firmicutes and an impressive array of fungi (usually pathogenic) serve as the source of a structurally diverse number of small molecules with important biological activities including antimicrobial, cytotoxic, antiparasitic and specific enzyme inhibitors. The insect niche is often the exclusive provider of microbes producing unique types of biologically active compounds such as gerumycins, pederin, dinactin, and formicamycins. However, numerous insects still have not been described taxonomically, and in most cases, the study of their microbiota is completely unexplored. In this review, we present a comprehensive survey of 553 natural products produced by microorganisms isolated from insects by collating and classifying all the data according to the type of compound (rather than the insect or microbial source). The analysis of the correlations among the metadata related to insects, microbial partners, and their produced compounds provides valuable insights into the intricate dynamics between insects and their symbionts as well as the impact of their metabolites on these relationships. Herein, we focus on the chemical structure, biosynthesis, and biological activities of the most relevant compounds.

Advances in biosynthesis and metabolic engineering strategies of cordycepin

Cordyceps militaris, also called as bei-chong-cao, is an insect-pathogenic fungus from the Ascomycota phylum and the Clavicipitaceae family. It is a valuable filamentous fungus with medicinal and edible properties that has been utilized in traditional Chinese medicine (TCM) and as a nutritious food. Cordycepin is the bioactive compound firstly isolated from C. militaris and has a variety of nutraceutical and health-promoting properties, making it widely employed in nutraceutical and pharmaceutical fields. Due to the low composition and paucity of wild resources, its availability from natural sources is limited. With the elucidation of the cordycepin biosynthetic pathway and the advent of synthetic biology, a green cordycepin biosynthesis in Saccharomyces cerevisiae and Metarhizium robertsii has been developed, indicating a potential sustainable production method of cordycepin. Given that, this review primarily focused on the metabolic engineering and heterologous biosynthesis strategies of cordycepin.

Genomic and Transcriptome Analysis Reveals the Biosynthesis Network of Cordycepin in Cordyceps militaris

Cordycepin is the primary active compound of Cordyceps militaris. However, the definitive genetic mechanism governing cordycepin synthesis in fruiting body growth and development remains elusive, necessitating further investigation. This study consists of 64 C. militaris strains collected from northeast China. The high-yielding cordycepin strain CMS19 was selected for the analysis of cordycepin production and the genetic basis of cordycepin anabolism. First, the whole-genome sequencing of CMS19 yielded a final size of 30.96 Mb with 8 contigs and 9781 protein-coding genes. The genome component revealed the presence of four additional secondary metabolite gene clusters compared with other published genomes, suggesting the potential for the production of new natural products. The analyses of evolutionary and genetic differentiation revealed a close relationship between C. militaris and Beauveria bassiana. The population of strains distributed in northeast China exhibited the significant genetic variation. Finally, functional genes associated with cordycepin synthesis were identified using a combination of genomic and transcriptomic analyses. A large number of functional genes associated with energy and purine metabolism were significantly enriched, facilitating the reconstruction of a hypothetical cordycepin metabolic pathway. Therefore, our speculation of the cordycepin metabolism pathway involved 24 genes initiating from the glycolysis and pentose phosphate pathways, progressing through purine metabolism, and culminating in the core region of cordycepin synthesis. These findings could offer fundamental support for scientific utilizations of C. militaris germplasm resources and standardized cultivation for cordycepin production.

Exploiting the roles of nitrogen sources for HEA increment in Cordyceps cicadae

Cordyceps cicadae, as a new food ingredient, is a valuable edible and medicinal fungi. However, its resources are severely depleted due to environmental limitations and excessive harvesting practices. N6-(2-hydroxyethyl) adenosine (HEA), as an important product of Cordyceps cicadae, has the potential to be used in medical industry due to its diverse disease curing potential. However, the disclosure of HEA synthesis still severely limited its application until now. In this study, the kinetic curves for adenosine and HEA under shaker fermentation were explored. The kinetics of HEA and adenosine production exhibited a competitive pattern, implicating a possibility of sharing a same step during their synthesis. Due to HEA as a derivative of nitrogen metabolism, the effect of different nitrogen sources (peptone, yeast extract, ammonium sulfate, diammonium oxalate monohydrate, ammonium citrate dibasic, and ammonium citrate tribasic) on HEA production in Cordyceps cicadae strain AH 10-4 had been explored under different incubation conditions (shaker fermentation, stationary fermentation, and submerged fermentation). Our results indicated that the complex organic nitrogen sources were found to improve the accumulation of HEA content under shaker fermentation. In contrast, the optimal nitrogen source for the accumulation of HEA under stationary fermentation and submerged fermentation was ammonium citrate tribasic. But submerged fermentation obviously shortened the incubation time and had a comparable capacity of HEA accumulation by 2.578 mg/g compared with stationary fermentation of 2.535 mg/g, implicating a possibility of scaled-up production of HEA in industry by submerged fermentation. Based on the dramatic HEA production by ammonium sulfate as nitrogen resources between stationary and shaker fermentations, alanine, aspartate and glutamate as well as arginine metabolic pathway were related to the production of HEA by comparative transcriptome. Further investigation indicated that glutamic acid, which is an analog of Asp, showed an optimum production of HEA in comparison with other amino acids.

Cordycepin alleviates hepatic fibrosis in association with the inhibition of glutaminolysis to promote hepatic stellate cell senescence

Cordycepin (CRD) is an active component derived from Cordyceps militaris, which possesses multiple biological activities and uses in liver disease. However, whether CRD improves liver fibrosis by regulating hepatic stellate cell (HSC) activation has remained unknown. The study aims further to clarify the activities of CRD on liver fibrosis and elucidate the possible mechanism. Our results demonstrated that CRD significantly relieved hepatocyte injury and inhibited HSC activation, alleviating hepatic fibrogenesis in the Diethyl 1,4-dihydro-2,4,6-trimethyl-3,5-pyridinedicarboxylate (DDC)-induced mice model. In vitro, CRD exhibited dose-dependent repress effects on HSC proliferation, migration, and pro-fibrotic function in TGF-β1-activated LX-2 and JS-1 cells. The functional enrichment analysis of RNA-seq data indicated that the pathway through which CRD alleviates HSC activation involves cellular senescence and cell cycle-related pathways. Furthermore, it was observed that CRD accumulated the number of senescence-associated a-galactosidase positive cells and the levels of senescencemarker p21, and provoked S phasearrestof activated HSC. Remarkably, CRD treatment abolished TGF-β-induced yes-associated protein (YAP) nuclear translocation that acts upstream of glutaminolysis in activated HSC. On the whole, CRD significantly inhibited glutaminolysis of activated-HSC and induced cell senescence through the YAP signaling pathway, consequently alleviating liver fibrosis, which may be a valuable supplement for treating liver fibrosis.

Elucidation of antioxidant activities of intracellular and extracellular polysaccharides from Cordyceps militaris in vitro and their protective effects on ulcerative colitis in vivo

In this study, we extracted the polysaccharides from C. militaris fruiting bodies (CFIPs), mycelial intracellular polysaccharides (CMIPs), and fermentation broth extracellular polysaccharides (CFEPs) to investigate their physicochemical properties, antioxidant capacities, and effects on oxazolone-induced zebrafish ulcerative colitis (UC). Our results revealed differences in monosaccharide composition and surface structure among CFIPs, CMIPs, and CFEPs. The molar ratios of glucose to mannose in CFIPs, glucose to xylose in CMIPs, and xylose to glucose in CFEPs were 7.57: 1.6, 7.26: 1.81, and 5.44: 2.98 respectively. Moreover, CFEPs exhibited significantly (p < 0.05) higher chemical antioxidant capacity compared to CMIPs and CFIPs. Surprisingly, CFEP treatment didn't show a significant effect in protecting against H2O2-induced oxidative damage in RAW 264.7 cells. After 3 d of treatment, the levels of ROS, MDA, and MPO in the CFIPs group exhibited a significant (p < 0.05) reduction by 37.82 %, 68.15 %, and 22.77 % respectively. Additionally, the ACP and AKP increased by 60.33 % and 96.99 %. Additionally, C. militaris polysaccharides (CMPs) were found to effectively improve UC by activating the MyD88/NF-κB signaling pathway in vivo. These findings confirm the distinct physicochemical properties of these three types of CMP and their potential for development into antioxidant-rich anti-inflammatory health foods.

Current Advances in the Functional Genes of Edible and Medicinal Fungi: Research Techniques, Functional Analysis, and Prospects

Functional genes encode various biological functions required for the life activities of organisms. By analyzing the functional genes of edible and medicinal fungi, varieties of edible and medicinal fungi can be improved to enhance their agronomic traits, growth rates, and ability to withstand adversity, thereby increasing yield and quality and promoting industrial development. With the rapid development of functional gene research technology and the publication of many whole-genome sequences of edible and medicinal fungi, genes related to important biological traits have been mined, located, and functionally analyzed. This paper summarizes the advantages and disadvantages of different functional gene research techniques and application examples for edible and medicinal fungi; systematically reviews the research progress of functional genes of edible and medicinal fungi in biological processes such as mating type, mycelium and fruit growth and development, substrate utilization and nutrient transport, environmental response, and the synthesis and regulation of important active substances; and proposes future research directions for functional gene research for edible and medicinal fungi. The overall aim of this study was to provide a valuable reference for further promoting the molecular breeding of edible and medicinal fungi with high yield and quality and to promote the wide application of edible and medicinal fungi products in food, medicine, and industry.

The biosynthetic logic and enzymatic machinery of approved fungi-derived pharmaceuticals and agricultural biopesticides

Covering: 2000 to 2023The kingdom Fungi has become a remarkably valuable source of structurally complex natural products (NPs) with diverse bioactivities. Since the revolutionary discovery and application of the antibiotic penicillin from Penicillium, a number of fungi-derived NPs have been developed and approved into pharmaceuticals and pesticide agents using traditional "activity-guided" approaches. Although emerging genome mining algorithms and surrogate expression hosts have brought revolutionary approaches to NP discovery, the time and costs involved in developing these into new drugs can still be prohibitively high. Therefore, it is essential to maximize the utility of existing drugs by rational design and systematic production of new chemical structures based on these drugs by synthetic biology. To this purpose, there have been great advances in characterizing the diversified biosynthetic gene clusters associated with the well-known drugs and in understanding the biosynthesis logic mechanisms and enzymatic transformation processes involved in their production. We describe advances made in the heterogeneous reconstruction of complex NP scaffolds using fungal polyketide synthases (PKSs), non-ribosomal peptide synthetases (NRPSs), PKS/NRPS hybrids, terpenoids, and indole alkaloids and also discuss mechanistic insights into metabolic engineering, pathway reprogramming, and cell factory development. Moreover, we suggest pathways for expanding access to the fungal chemical repertoire by biosynthesis of representative family members via common platform intermediates and through the rational manipulation of natural biosynthetic machineries for drug discovery.

Biological characteristics of Cordyceps militaris single mating-type strains

Cordyceps militaris has been extensively cultivated as a model cordyceps species for commercial purposes. Nevertheless, the problems related to strain degeneration and breeding technologies remain unresolved. This study assessed the physiology and fertility traits of six C. militaris strains with distinct origins and characteristics, focusing on single mating-type strains. The results demonstrated that the three identified strains (CMDB01, CMSY01, and CMJB02) were single mating-type possessing only one mating-type gene (MAT1-1). In contrast, the other three strains (CMXF07, CMXF09, and CMMS05) were the dual mating type. The MAT1-1 strains sourced from CMDB01, CMSY01, and CMJB02 consistently produced sporocarps but failed to generate ascospores. However, when paired with MAT1-2 strains, the MAT1-1 strains with slender fruiting bodies and normal morphology were fertile. The hyphal growth rate of single mating-type strains (CMDB01, CMSY01, and CMJB02) typically surpassed that of dual mating-type strains (CMXF07, CMXF09, and CMMS05). The growth rates of MAT1-2 and MAT1-1 strains were proportional to their ratios, such that a single mating-type strain with a higher ratio exhibited an increased growth rate. As C. militaris matured, the adenosine content decreased. In summary, the C. militaris strains that consistently produce sporocarps and have a single mating type are highly promising for production and breeding.

Cordyceps as potential therapeutic agents for atherosclerosis

Atherosclerosis is a leading cause of mortality and morbidity worldwide. Despite the challenges in managing atherosclerosis, researchers continue to investigate new treatments and complementary therapies. Cordyceps is a traditional Chinese medicine that has recently gained attention as a potential therapeutic agent for atherosclerosis. Numerous studies have demonstrated the effectiveness of cordyceps in treating atherosclerosis through various pharmacological actions, including anti-inflammatory and antioxidant activities, lowering cholesterol, inhibiting platelet aggregation, and modulating apoptosis or autophagy in vascular endothelial cells. Notably, the current misuse of the terms cordyceps and Ophiocordyceps sinensis has caused confusion among researchers, and complicated the current academic research on cordyceps. This review focuses on the chemical composition, pharmacological actions, and underlying mechanisms contributing to the anti-atherosclerotic effects of cordyceps and the mycelium of Ophiocordyceps spp. This review provides a resource for the research on the development of new drugs for atherosclerosis from cordyceps. Please cite this article as: Zhang Y, Liu SJ. Cordyceps as potential therapeutic agents for atherosclerosis. J Integr Med. 2024; 22(2): 102-114.

Ethanolic extract from fruiting bodies of Cordyceps militaris HL8 exhibits cytotoxic activities against cancer cells, skin pathogenic yeasts, and postharvest pathogen Penicillium digitatum

Cordyceps militaris is a well-known medicinal mushroom in Asian countries. This edible fungus has been widely exploited for traditional medicine and functional food production. C. militaris is a heterothallic fungus that requires both the mating-type loci, MAT1-1 and MAT1-2, for fruiting body formation. However, recent studies also indicated two groups of C. militaris, including monokaryotic strains carrying only MAT1-1 in their genomes and heterokaryotic strains harboring both MAT1-1 and MAT1-2. These strain groups are able to produce fruiting bodies under suitable cultivating conditions. In previous work, we showed that monokaryotic strains are more stable than heterokaryotic strains in fruiting body formation through successive culturing generations. In this study, we report a high cordycepin-producing monokaryotic C. militaris strain (HL8) collected in Vietnam. This strain could form normal fruiting bodies with high biological efficiency and contain a cordycepin content of 14.43 mg/g lyophilized fruiting body biomass. The ethanol extraction of the HL8 fruiting bodies resulted in a crude extract with a cordycepin content of 69.15 mg/g. Assays of cytotoxic activity on six human cancer cell lines showed that the extract inhibited the growth of all these cell lines with the IC50 values of 6.41-11.51 µg/mL. Notably, the extract significantly reduced cell proliferation and promoted apoptosis of breast cancer cells. Furthermore, the extract also exhibited strong antifungal activity against Malassezia skin yeasts and the citrus postharvest pathogen Penicillium digitatum. Our work provides a promising monokaryotic C. militaris strain as a bioresource for medicine, cosmetics, and fruit preservation.

Unique Bioactives from Zombie Fungus (Cordyceps) as Promising Multitargeted Neuroprotective Agents

Cordyceps, also known as "zombie fungus", is a non-poisonous mushroom that parasitizes insects for growth and development by manipulating the host system in a way that makes the victim behave like a "zombie". These species produce promising bioactive metabolites, like adenosine, β-glucans, cordycepin, and ergosterol. Cordyceps has been used in traditional medicine due to its immense health benefits, as it boosts stamina, appetite, immunity, longevity, libido, memory, and sleep. Neuronal loss is the typical feature of neurodegenerative diseases (NDs) (Alzheimer's disease (AD), Parkinson's disease (PD), multiple sclerosis (MS), amyotrophic lateral sclerosis (ALS)) and neurotrauma. Both these conditions share common pathophysiological features, like oxidative stress, neuroinflammation, and glutamatergic excitotoxicity. Cordyceps bioactives (adenosine, N6-(2-hydroxyethyl)-adenosine, ergosta-7, 9 (11), 22-trien-3β-ol, active peptides, and polysaccharides) exert potential antioxidant, anti-inflammatory, and anti-apoptotic activities and display beneficial effects in the management and/or treatment of neurodegenerative disorders in vitro and in vivo. Although a considerable list of compounds is available from Cordyceps, only a few have been evaluated for their neuroprotective potential and still lack information for clinical trials. In this review, the neuroprotective mechanisms and safety profile of Cordyceps extracts/bioactives have been discussed, which might be helpful in the identification of novel potential therapeutic entities in the future.

Efficient de novo production of bioactive cordycepin by Aspergillus oryzae using a food-grade expression platform

BACKGROUND

Cordycepin (3'-deoxyadenosine) is an important bioactive compound in medical and healthcare markets. The drawbacks of commercial cordycepin production using Cordyceps spp. include long cultivation periods and low cordycepin yields. To overcome these limitations and meet the increasing market demand, the efficient production of cordycepin by the GRAS-status Aspergillus oryzae strain using a synthetic biology approach was developed in this study.

RESULTS

An engineered strain of A. oryzae capable of cordycepin production was successfully constructed by overexpressing two metabolic genes (cns1 and cns2) involved in cordycepin biosynthesis under the control of constitutive promoters. Investigation of the flexibility of carbon utilization for cordycepin production by the engineered A. oryzae strain revealed that it was able to utilize C6-, C5-, and C12-sugars as carbon sources, with glucose being the best carbon source for cordycepin production. High cordycepin productivity (564.64 ± 9.59 mg/L/d) was acquired by optimizing the submerged fermentation conditions.

CONCLUSIONS

This study demonstrates a powerful production platform for bioactive cordycepin production by A. oryzae using a synthetic biology approach. An efficient and cost-effective fermentation process for cordycepin production using an engineered strain was established, offering a powerful alternative source for further upscaling.

Multifactorial interaction of selenium, iron, xylose, and glycine on cordycepin metabolism in Cordyceps militaris

Cordycepin, a nucleoside analog, is the main antioxidative and antimicrobial substance in Cordyceps militaris. To improve the metabolism of cordycepin, carbon sources, nitrogen sources, trace elements, and precursors were studied by single factor, Plackett-Burman, and central composite designs in C. militaris mycelial fermentation. Under the regulation of the multifactorial interactions of selenite, ferrous chloride, xylose, and glycine, cordycepin production was increased by 5.2-fold compared with the control. The gene expression of hexokinase, ATP phosphoribosyltransferase, adenylosuccinate synthetase, and cns1-3 in the glycolysis, pentose phosphate, and adenosine synthesis pathways were increased by 3.2-7.5 times due to multifactorial interactions, while the gene expression of histidine biosynthesis trifunctional protein and histidinol-phosphate aminotransferase in histidine synthesis pathway were decreased by 23.4%-56.2%. Increasing with cordycepin production, glucose uptake was accelerated, mycelia growth was inhibited, and the cell wall was damaged. Selenomethionine (SeMet), selenocysteine (SeCys), and selenium nanoparticles (SeNPs) were the major Se species in C. militaris mycelia. This study provides a new insight for promoting cordycepin production by regulating glycolysis, pentose phosphate, and histidine metabolism. KEY POINTS: • Cordycepin production in the CCDmax group was 5.2-fold than that of the control. • Glucose uptake of the CCDmax group was accelerated and cell wall was damaged. • The metabolic flux was concentrated to the cordycepin synthesis pathway.

High-level production of cordycepin by the xylose-utilising Cordyceps militaris strain 147 in an optimised medium

Cordycepin is an important active metabolite of Cordyceps militaris. Xylose, an attractive feedstock for producing chemicals through microbial fermentation, cannot be effectively utilised by many reported C. militaris strains. Herein, a xylose-utilising C. militaris strain 147 produced the highest level of cordycepin (3.03 g/L) in xylose culture. Xylose, alanine, and ammonium citrate were determined as the main affecting factors on the cordycepin production using a Plackett-Burman design. The combination of these factors was optimised using response surface methodology, and the maximal 6.54 g/L of cordycepin was produced by the fungus in the optimal medium. Transcriptome analysis revealed that xylose utilisation upregulated the transcriptional levels of genes participating in purine and energy metabolisms in the fungus, which may facilitate the formation of precursors for cordycepin biosynthesis. This investigation provides new insights into the efficient production of cordycepin and is conducive to the valorisation of biomass rich in xylose.

Integrated omic profiling of the medicinal mushroom Inonotus obliquus under submerged conditions

BACKGROUND

The Inonotus obliquus mushroom, a wondrous fungus boasting edible and medicinal qualities, has been widely used as a folk medicine and shown to have many potential pharmacological secondary metabolites. The purpose of this study was to supply a global landscape of genome-based integrated omic analysis of the fungus under lab-growth conditions.

RESULTS

This study presented a genome with high accuracy and completeness using the Pacbio Sequel II third-generation sequencing method. The de novo assembled fungal genome was 36.13 Mb, and contained 8352 predicted protein-coding genes, of which 365 carbohydrate-active enzyme (CAZyme)-coding genes and 19 biosynthetic gene clusters (BCGs) for secondary metabolites were identified. Comparative transcriptomic and proteomic analysis revealed a global view of differential metabolic change between seed and fermentation culture, and demonstrated positive correlations between transcription and expression levels of 157 differentially expressed genes involved in the metabolism of amino acids, fatty acids, secondary metabolites, antioxidant and immune responses. Facilitated by the widely targeted metabolomic approach, a total of 307 secondary substances were identified and quantified, with a significant increase in the production of antioxidant polyphenols.

CONCLUSION

This study provided the comprehensive analysis of the fungus Inonotus obliquus, and supplied fundamental information for further screening of promising target metabolites and exploring the link between the genome and metabolites.

Optogenetic control of Cdc48 for dynamic metabolic engineering in yeast

Dynamic metabolic engineering is a strategy to switch key metabolic pathways in microbial cell factories from biomass generation to accumulation of target products. Here, we demonstrate that optogenetic intervention in the cell cycle of budding yeast can be used to increase production of valuable chemicals, such as the terpenoid β-carotene or the nucleoside analog cordycepin. We achieved optogenetic cell-cycle arrest in the G2/M phase by controlling activity of the ubiquitin-proteasome system hub Cdc48. To analyze the metabolic capacities in the cell cycle arrested yeast strain, we studied their proteomes by timsTOF mass spectrometry. This revealed widespread, but highly distinct abundance changes of metabolic key enzymes. Integration of the proteomics data in protein-constrained metabolic models demonstrated modulation of fluxes directly associated with terpenoid production as well as metabolic subsystems involved in protein biosynthesis, cell wall synthesis, and cofactor biosynthesis. These results demonstrate that optogenetically triggered cell cycle intervention is an option to increase the yields of compounds synthesized in a cellular factory by reallocation of metabolic resources.

Cordycepin: A review of strategies to improve the bioavailability and efficacy

Cordycepin is a bioactive compound extracted from Cordyceps militaris. As a natural antibiotic, cordycepin has a wide variety of pharmacological effects. Unfortunately, this highly effective natural antibiotic is proved to undergo rapid deamination by adenosine deaminase (ADA) in vivo and, as a consequence, its half-life is shortened and bioavailability is decreased. Therefore, it is of critical importance to work out ways to slow down the deamination so as to increase its bioavailability and efficacy. This study reviews recent researches on a series of aspects of cordycepin such as the bioactive molecule's pharmacological action, metabolism and transformation as well as the underlying mechanism, pharmacokinetics and, particularly, the methods for reducing the degradation to improve the bioavailability and efficacy. It is drawn that there are three methods that can be applied to improve the bioavailability and efficacy: to co-administrate an ADA inhibitor and cordycepin, to develop more effective derivatives via structural modification, and to apply new drug delivery systems. The new knowledge can help optimize the application of the highly potent natural antibiotic-cordycepin and develop novel therapeutic strategies.

Molecular Phylogeny and Morphology Reveal Cryptic Species in the Cordyceps militaris Complex from Vietnam

The Cordyceps militaris complex, which is a special group in the genus Cordyceps, is rich in species diversity and is widely distributed in nature. Throughout the investigations of arthropod-pathogenic fungi in the national reserves and in Vietnam parks, collections of C. militaris attacking lepidopteran pupae or larvae were located in the soil and on the leaf litter. The phylogenetic analyses of the combined nrSSU, nrLSU, TEF, RPB1, and RPB2 sequence data indicated that the fungal materials collected in Vietnam belonged to C. militaris and two hidden species in the C. militaris complex. The phylogenetic analyses and morphological comparisons presented here strongly supported the descriptions of C. polystromata and C. sapaensis as new taxa as well as C. militaris as a known species. The morphological characteristics of 11 species in the C. militaris complex, which included two novel species and nine known taxa, were also compared.

Fungus-insect interactions beyond bilateral regimes: the importance and strategy to outcompete host ectomicrobiomes by fungal parasites

Fungus-insect interactions have long been investigated at the bilateral level to unveil the factors involved in mediating fungal entomopathogenicity and insect antifungal immunity. Emerging evidence has shown that insect cuticles are inhabited by different bacteria that can delay and deter fungal parasite infections. Entomopathogenic fungi (EPF), however, have evolved strategies to combat the colonization resistance mediated by insect ectomicrobiomes by producing antimicrobial peptides or antibiotic compounds. Deprivation of micronutrients may also be employed by EPF to counteract the ectomicrobiome antagonism. Further investigations of insect ectomicrobiome assemblage and fungal factors involved in outcompeting cuticular microbiomes may benefit the development of cost-effective mycoinsecticides while protecting ecologically and economically important insect species.

Adenosine Deaminase Inhibitory Activity of Medicinal Plants: Boost the Production of Cordycepin in Cordyceps militaris

Cordycepin, also known as 3'-deoxyadenosine, is a major active ingredient of Cordyceps militaris with diverse pharmacological effects. Due to its limited supply, many attempts have been conducted to enhance the cordycepin content. As part of this study, eight medicinal plants were supplemented with cultivation substrates of Cordyceps to increase the cordycepin content. Cordyceps cultivated on brown rice supplemented with Mori Folium, Curcumae Rhizoma, Saururi Herba, and Angelicae Gigantis Radix exhibited increased cordycepin content compared to a brown rice control. Among them, the addition of 25% Mori Folium increased the cordycepin content up to 4 times. Adenosine deaminase (ADA) modulates the deamination of adenosine and deoxyadenosine, and the inhibitors have therapeutic potential with anti-proliferative and anti-inflammatory properties. As ADA is also known to be involved in converting cordycepin to 3'-deoxyinosine, the inhibitory activity of medicinal plants on ADA was measured by spectrophotometric analysis using cordycepin as a substrate. As expected, Mori Folium, Curcumae Rhizoma, Saururi Herba, and Angelicae Gigas Radix strongly inhibited ADA activity. Molecular docking analysis also showed the correlation between ADA and the major components of these medicinal plants. Conclusively, our research suggests a new strategy of using medicinal plants to enhance cordycepin production in C. militaris.

Efficient production of cordycepin by engineered Yarrowia lipolytica from agro-industrial residues

Cordycepin, a nucleoside compound with a variety of biological activities, has been extensively applied in the nutraceutical and pharmaceutical industries. The advancement of microbial cell factories using agro-industrial residues provides a sustainable pathway for cordycepin biosynthesis. Herein, the cordycepin production was enhanced by the modification of glycolysis and pentose phosphate pathway in engineered Yarrowia lipolytica. Then, cordycepin production based on economical and renewable substrates (sugarcane molasses, waste spent yeast, and diammonium hydrogen phosphate) was analyzed. Furthermore, the effects of C/N molar ratio and initial pH on cordycepin production were evaluated. Results indicated that the maximum cordycepin productivity of 656.27 mg/L/d (72 h) and cordycepin titer was 2286.04 mg/L (120 h) by engineered Y. lipolytica in the optimized medium, respectively. The cordycepin productivity in the optimized medium was increased by 28.81% compared with the original medium. This research establishes a promising way for efficient cordycepin production from agro-industrial residues.

Functional genomics and systems biology of Cordyceps species for biotechnological applications

The use of Cordyceps species for the manufacture of natural products has been established; however, the tremendous advances observed in recent years in genetic engineering and molecular biology have revolutionized the optimization of Cordyceps as cell factories and drastically expanded the biotechnological potential of these fungi. Here, we present a review of systems and synthetic biology studies of Cordyceps and their implications for fungal biology and industrial applications. We summarize the current status of synthetic biology for enhancing targeted metabolites in Cordyceps species, such as cordycepin, adenosine, polysaccharide, and pentostatin. Progress in the systems and synthetic biology of Cordyceps provides a strategy for comprehensively comprehensive controlling efficient cell factories of natural bioproducts and novel synthetic biology toolbox for targeted engineering.

Integrated enzymes activity and transcriptome reveal the effect of exogenous melatonin on the strain degeneration of Cordyceps militaris

As a valuable medicinal and edible fungus, Cordyceps militaris has been industrialized with broad development prospects. It contains a lot of bioactive compounds that are beneficial to our health. However, during artificial cultivation, strain degeneration is a challenge that inhibits the industrialization utility of C. militaris. Exogenous melatonin (MT) can scavenge for reactive oxygen species (ROS) in fungus and can alleviate strain degeneration. To establish the significance and molecular mechanisms of MT on strain degeneration, we investigated the third-generation strain (W5-3) of C. militaris via morphological, biochemical, and transcriptomic approaches under MT treatment. Morphological analyses revealed that colony angulation of C. militaris was significantly weakened, and the aerial hypha was reduced by 60 μmol L-1 MT treatment. Biochemical analyses showed low levels of ROS and malondialdehyde (MDA), as well as increasing endogenous MT levels as exogenous MT increased. RNA-Seq revealed that compared with the control, several antioxidant enzyme-related genes were up-regulated under 60 μmol L-1 MT treatment. Among them, glutathione s-transferase genes were up-regulated by a factor of 11.04. In addition, genes that are potentially involved in cordycepin, adenosine and active compound biosynthesis for the growth and development of mycelium were up-regulated. Collectively, these findings provide the basis for further elucidation of the molecular mechanisms involved in C. militaris strain degeneration.

Multi-omics analysis unravels positive effect of rotenone on the cordycepin biosynthesis in submerged fermentation of Cordyceps militaris

Cordycepin is the key pharmacologically active compound of Cordyceps militaris, and various fermentation strategies have been developed to increase cordycepin production. This study aimed to investigate the effect of rotenone on cordycepin biosynthesis in submerged fermentation of C. militaris, and also to explore its possible induction mechanisms via multi-omics analysis. Adding 5 mg/L rotenone significantly increased the cordycepin production by 316.09 %, along with mycelial growth inhibition and cell wall destruction. Moreover, transcriptomic analysis and metabolomic analysis revealed the accumulation of cordycepin was promoted by alterations in energy metabolism and amino acid metabolism pathways. Finally, the integration analysis of the two omics confirmed rotenone altered the nucleotide metabolism pathway toward adenosine and up-regulated the cordycepin synthesis genes (cns1-3) to convert adenosine to cordycepin. This work reports, for the first time, rotenone could act as an effective inducer of cordycepin synthesis.

Increased Cordycepin Production in Yarrowia lipolytica Using Combinatorial Metabolic Engineering Strategies

As the first nucleoside antibiotic discovered in fungi, cordycepin, with its various biological activities, has wide applications. At present, cordycepin is mainly obtained from the natural fruiting bodies of Cordyceps militaris. However, due to long production periods, low yields, and low extraction efficiency, harvesting cordycepin from natural C. militaris is not ideal, making it difficult to meet market demands. In this study, an engineered Yarrowia lipolytica YlCor-18 strain, constructed by combining metabolic engineering strategies, achieved efficient de novo cordycepin production from glucose. First, the cordycepin biosynthetic pathway derived from C. militaris was introduced into Y. lipolytica. Furthermore, metabolic engineering strategies including promoter, protein, adenosine triphosphate, and precursor engineering were combined to enhance the synthetic ability of engineered strains of cordycepin. Fermentation conditions were also optimized, after which, the production titer and yields of cordycepin in the engineered strain YlCor-18 under fed-batch fermentation were improved to 4362.54 mg/L and 213.85 mg/g, respectively, after 168 h. This study demonstrates the potential of Y. lipolytica as a cell factory for cordycepin synthesis, which will serve as the model for the green biomanufacturing of other nucleoside antibiotics using artificial cell factories.

Development of an efficient method for separation and purification of cordycepin from liquid fermentation of Cordyceps militaris and analysis of cordycepin antitumor activity

Cordycepin (3 '-deoxyadenosine) is the main active component of Cordyceps militaris, which is a chemical marker for quality detection of Cordyceps militaris and has important medicinal development value. Existing methods for obtaining cordycepin are complex and costly. In this study, an economical and simple method for separation and purification of cordycepin from Cordyceps militaris fermentation liquid through physical crystallization was explored. First, lyophilized powdered fermentation liquid (LPFL) and pure methanol (1 g/100 mL, w/v) were mixed, and then repeatedly dissolved and crystallized until the precipitation was white. Purified product was obtained by freeze-drying the precipitate. The substance was determined to be cordycepin by high performance liquid chromatography, mass spectrometry and infrared spectroscopy, and the purity was 94.26%. Compared with the existing methods, this method is simple and low cost. In addition, the functional activity of cordycepin was determined by in vitro test. The results exhibited that cordycepin caused death and morphological changes in human colon cancer Caco-2 cells, and significantly inhibited the proliferation of Caco-2 cells, with a half-maximal inhibitory concentration (IC₅₀) of 107.2 μg/mL. Cordycepin could induce early apoptosis of Caco-2 and caused cell cycle arrest in the G2 phase. Caco-2 cell apoptosis and cell cycle arrest showed dose dependence to cordycepin over a certain range. These results improved cordycepin purification method, provided insights into the mechanism of cordycepin in cancer inhibition, and would provide important reference for further development and clinical application of cordycepin.

Engineering Komagataella phaffii to biosynthesize cordycepin from methanol which drives global metabolic alterations at the transcription level

Cordycepin has the potential to be an alternative to the disputed herbicide glyphosate. However, current laborious and time-consuming production strategies at low yields based on Cordyceps militaris lead to extremely high cost and restrict its application in the field of agriculture. In this study, Komagataella phaffii (syn. Pichia pastoris) was engineered to biosynthesize cordycepin from methanol, which could be converted from CO₂. Combined with fermentation optimization, cordycepin content in broth reached as high as 2.68 ± 0.04 g/L within 168 h, around 15.95 mg/(L·h) in productivity. Additionally, a deaminated product of cordycepin was identified at neutral or weakly alkaline starting pH during fermentation. Transcriptome analysis found the yeast producing cordycepin was experiencing severe inhibition in methanol assimilation and peroxisome biogenesis, responsible for delayed growth and decreased carbon flux to pentose phosphate pathway (PPP) which led to lack of precursor supply. Amino acid interconversion and disruption in RNA metabolism were also due to accumulation of cordycepin. The study provided a unique platform for the manufacture of cordycepin based on the emerging non-conventional yeast and gave practical strategies for further optimization of the microbial cell factory.

Hydrophobin Gene Cmhyd4 Negatively Regulates Fruiting Body Development in Edible Fungi Cordyceps militaris

A deep understanding of the mechanism of fruiting body development is important for mushroom breeding and cultivation. Hydrophobins, small proteins exclusively secreted by fungi, have been proven to regulate the fruiting body development in many macro fungi. In this study, the hydrophobin gene Cmhyd4 was revealed to negatively regulate the fruiting body development in Cordyceps militaris, a famous edible and medicinal mushroom. Neither the overexpression nor the deletion of Cmhyd4 affected the mycelial growth rate, the hydrophobicity of the mycelia and conidia, or the conidial virulence on silkworm pupae. There was also no difference between the micromorphology of the hyphae and conidia in WT and ΔCmhyd4 strains observed by SEM. However, the ΔCmhyd4 strain showed thicker aerial mycelia in darkness and quicker growth rates under abiotic stress than the WT strain. The deletion of Cmhyd4 could promote conidia production and increase the contents of carotenoid and adenosine. The biological efficiency of the fruiting body was remarkably increased in the ΔCmhyd4 strain compared with the WT strain by improving the fruiting body density, not the height. It was indicated that Cmhyd4 played a negative role in fruiting body development. These results revealed that the diverse negative roles and regulatory effects of Cmhyd4 were totally different from those of Cmhyd1 in C. militaris and provided insights into the developmental regulatory mechanism of C. militaris and candidate genes for C. militaris strain breeding.

Poly-pathways metabolomics for high-yielding cordycepin of Cordyceps militaris

Cordycepin is an important quality control marker in Cordyceps militaris. This study aimed to explain the metabolic mechanisms for high-yielding cordycepin of C. militaris. In this study, high-yielding strains of cordycepin were obtained by ultraviolet mutagenesis, and the polysaccharide and protein contents were also changed. In high-yielding strains, the protein content significantly increased, whereas the polysaccharide content decreased. Simultaneously, metabolic differences for high- and low-yielding cordycepin strains were detected by metabolomics. Metabolomics results showed that the relative content of most metabolites decreased in high-yielding cordycepin strains. Various metabolic pathways have been altered in high-yielding cordycepin strains, such as the citric acid cycle, purine metabolism, and pyrimidine metabolism, leading to an increase in cordycepin content. In addition, changes in metabolic poly-pathways related to polysaccharide and protein synthesis, such as galactose metabolism and amino acid metabolism, promoted an increase in cordycepin content. This study analyzes the high yield of cordycepin in C. militaris at the metabolic level and provides a theoretical basis for further increasing cordycepin content.

Transcriptome and metabolome profiling unveils the mechanisms of naphthalene acetic acid in promoting cordycepin synthesis in Cordyceps militaris

Cordycepin, an important active substance in Cordyceps militaris, possesses antiviral and other beneficial activities. In addition, it has been reported to effectively promote the comprehensive treatment of COVID-19 and thus has become a research hotspot. The addition of naphthalene acetic acid (NAA) is known to significantly improve the yield of cordycepin; however, its related molecular mechanism remains unclear. We conducted a preliminary study on C. militaris with different concentrations of NAA. We found that treatment with different concentrations of NAA inhibited the growth of C. militaris, and an increase in its concentration significantly improved the cordycepin content. In addition, we conducted a transcriptome and metabolomics association analysis on C. militaris treated with NAA to understand the relevant metabolic pathway of cordycepin synthesis under NAA treatment and elucidate the relevant regulatory network of cordycepin synthesis. Weighted gene co-expression network analysis (WGCNA), transcriptome, and metabolome association analysis revealed that genes and metabolites encoding cordycepin synthesis in the purine metabolic pathway varied significantly with the concentration of NAA. Finally, we proposed a metabolic pathway by analyzing the relationship between gene-gene and gene-metabolite regulatory networks, including the interaction of cordycepin synthesis key genes; key metabolites; purine metabolism; TCA cycle; pentose phosphate pathway; alanine, aspartate, and glutamate metabolism; and histidine metabolism. In addition, we found the ABC transporter pathway to be significantly enriched. The ABC transporters are known to transport numerous amino acids, such as L-glutamate, and participate in the amino acid metabolism that affects the synthesis of cordycepin. Altogether, multiple channels work together to double the cordycepin yield, thereby providing an important reference for the molecular network relationship between the transcription and metabolism of cordycepin synthesis.

Simultaneous determination of cordycepin and its metabolite 3'-deoxyinosine in rat whole blood by ultra-high-performance liquid chromatography coupled with Q Exactive hybrid quadrupole orbitrap high-resolution accurate mass spectrometry and its application to accurate pharmacokinetic studies

Cordycepin from Cordyceps possesses excellent pharmacological properties, including anti-inflammation and anti-tumor effects, therefore representing a potential alternative medicine. However, doubts about the pharmacokinetic results of cordycepin had been raised in the previous study due to its rapid deamination. The organic solvent methanol was immediately added to terminate the degradation of cordycepin in anticoagulated blood samples and enable the accurate evaluation of pharmacokinetics in vivo. A sensitive and selective ultra-high-performance liquid chromatography coupled with Q Exactive hybrid quadrupole orbitrap high-resolution accurate mass spectrometry method was developed and validated to simultaneously determine cordycepin and its deamination metabolite 3'-deoxyinosine using 2-chloroadenosine as an internal standard in rat whole blood. The calibration curves of cordycepin and 3'-deoxyinosine showed excellent linearity within the concentration range of 1.05-10 000.00 ng/ml with acceptable accuracy, precision, selectivity, recovery, matrix effect, and stability. This method was successfully applied to the pharmacokinetic study of cordycepin and its metabolite in rat blood. The effect of the adenosine deaminase inhibitor erythro-9-(2-hydroxy-3-nonyl) adenine hydrochloride on the pharmacokinetics of cordycepin was investigated. In summary, the reliable pharmacokinetic parameters of cordycepin and its deamination metabolite 3'-deoxyinosine in rat blood were successfully elucidated. Erythro-9-(2-hydroxy-3-nonyl) adenine hydrochloride considerably prolonged the half-life of cordycepin in vivo.

Cordycepin Enhances the Cytotoxicity of Human Natural Killer Cells against Cancerous Cells

Cancer treatment with natural killer (NK) cell immunotherapy is promising. NK cells can recognize and kill cancer cells without sensitization, making them a potential cancer treatment alternative. To improve clinical efficacy and safety, more research is needed. Enhancing NK cell function improves therapeutic efficacy. Due to its potent apoptosis induction, Cordycepin, a bioactive compound from Cordyceps spp., inhibits cancer cell growth. Cordycepin has immunoregulatory properties, making it a promising candidate for combination therapy with NK cell-based immunotherapy. Cordycepin may enhance NK cell function and have clinical applications, but more research is needed. In this study, cordycepin treatment of NK-92 MI cells increased THP-1 and U-251 cell cytotoxicity. Cordycepin also significantly increased the mRNA expression of cytokine-encoding genes, including tumour necrosis factor (TNF), interferon gamma (IFNG), and interleukin 2 (IL2). NK-92 MI cells notably secreted more IFNG and granzyme B. Cordycepin also decreased CD27 and increased CD11b, CD16, and NKG2D in NK-92 MI cells, which improved its anti-cancer ability. In conclusion, cordycepin could enhance NK cell cytotoxicity against cancerous cells for the first time, supporting its use as an alternative immunoactivity agent against cancer cells. Further studies are needed to investigate its efficacy and safety in clinical settings.

Effects of Exogenous Lanthanum Nitrate on the Active Substance Content and Antioxidant Activity of Caterpillar Medicinal Mushroom Cordyceps militaris (Ascomycetes)

Cordyceps militaris is a medicinal and edible mushroom. Researchers often add exogenous substances to the culture medium to increase the active substance content in C. militaris. However, the effect of earth elements on the active substance content in C. militaris and its antioxidant effects have not been reported. In this study, the active substance content in C. militaris treated with lanthanum nitrate was determined using high-performance liquid chromatography and ultraviolet spectrophotometry, and the effect on the antioxidant capacity of C. militaris after lanthanum nitrate spraying was further explored. The results showed that, in the experimental concentration range, the two concentrations of 10 mg/L and 50 mg/L had a significant influence on the active substance content of C. militaris. When the concentration of lanthanum nitrate was 10 mg/L, the synthesis of pentostatin and cordycepin was promoted. When the concentration of lanthanum nitrate was 50 mg/L, it significantly promoted the synthesis of cordycepin, and the ferric-reducing power and DPPH· scavenging rate of C. militaris treated at this concentration were significantly higher than those of the control group. However, lanthanum nitrate had no significant effect on ergosterol synthesis (P > 0.05). Finally, considering that the residual amount of lanthanum in C. militaris and the residual amount of lanthanum in 50 mg/L lanthanum nitrate-treated C. militaris is within the allowable daily intake of 4.2 mg for humans, the optimal concentration of lanthanum nitrate-treated C. militaris is 50 mg/L.

Integration of network pharmacology and molecular docking to explore the molecular mechanism of Cordycepin in the treatment of Alzheimer's disease

Background

Cordycepin is a nucleoside adenosine analog and an active ingredient isolated from the liquid fermentation of Cordyceps. This study sought to explore the mechanism underlying the therapeutic effect of Cordycepin against Alzheimer's disease using network pharmacology and molecular docking technology.

Methods

TCMSP, SYMMAP, CTD, Super-pred, SEA, GeneCards, DisGeNET database, and STRING platform were used to screen and construct the target and protein interaction network of Cordycepin for Alzheimer's disease. The results of Gene Ontology annotation and KEGG pathway enrichment analysis were obtained based on the DAVID database. The Omicshare database was also applied in GO and KEGG pathway enrichment analysis of the key targets. The protein-protein interaction network was constructed using the STRING database, and the potential effective targets for AD were screened based on the degree values. The correlation between the potential targets of Cordycepin in the treatment of AD and APP, MAPT, and PSEN2 was analyzed using (GEPIA) databases. We obtained potential targets related to aging using the Aging Altas database. Molecular docking analysis was performed by AutoDock Vina and Pymol software. Finally, we validated the significant therapeutic targets in the Gene Expression Omnibus (GEO) database.

Results

A total of 74 potential targets of Cordycepin for treating Alzheimer's disease were identified. The potential targets of Cordycepin for the treatment of AD mainly focused on Lipid and atherosclerosis (hsa05417), Platinum drug resistance (hsa01524), Apoptosis (hsa04210), and Pathways in cancer (hsa05200). Our findings suggest that the therapeutic effect of Cordycepin on AD is primarily associated with these biological processes. We obtained 12 potential therapeutic targets for AD using the degree value in Cytoscape. Interestingly, AKT1, MAPK8, BCL2L1, FOXO3, and CTNNB1 were not only significantly associated with pathogenic genes (APP, MAPT, and PSEN2) but also with longevity in Alzheimer's Disease. Thus we speculated that the five target genes were potential core targets mediating the therapeutic effect of Cordycepin against AD. Moreover, molecular docking results analysis showed good binding affinity between Cordycepin and the five core targets. Overall, MAPK8, FOXO3 and CTNNB1 may have significant clinical and treatment implications.

Conclusion

Network pharmacology demonstrated that Cordycepin exerts a therapeutic effect against Alzheimer's disease via multiple targets and signaling pathways and has huge prospects for application in treating neurodegenerative diseases.

Construction of Cordycepin High-Production Strain and Optimization of Culture Conditions

This study aimed to increase cordycepin production by over-expressing bio-synthetic enzyme genes, including the adenylosuccinate synthase, adenylosuccinate lyase, and 5'-nucleotidase genes. Research data showed that the extracellular and intracellular cordycepin concent of 24 recombinant strains were higher than those of C. militaris WT, indicating that over-expression of key enzyme genes increased cordycepin production. Among them, the CM-adss-5 strain had highest cordycepin production, and the extracellular and intracellular cordycepin concent were 1119.75 ± 1.61 and 65.56 ± 0.97 mg/L, which were 1.26 and 2.61 times that of C. militaris WT. This study also optimized the culture conditions of CM-adss-5 strain through single factor experiments to obtain the best culture conditions. The best culture condition was 25 °C constant temperature, 180-rpm shaking culture, fermentation period 12 days, inoculate amount 5%, initial pH 6, seed age 108 h, and liquid volume 110/250 mL. Then, the extracellular and intracellular cordycepin content of CM-adss-5 strain reached 2581.96 ± 21.07 and 164.08 ± 1.44 mg/L, which were higher by 130.6% and 150.3%, respectively. Therefore, our research provides a way to efficiently produce cordycepin for the development of cordycepin and its downstream products.

A simple, rapid, sensitive and eco-friendly LC-MS/MS method for simultaneous determination of free cordycepin and isocordycepin in 10 different kinds of Cordyceps

A simple, rapid, sensitive and eco-friendly liquid chromatography tandem mass spectrometry (LC-MS/MS) method was developed for simultaneous determination of free cordycepin (3′-deoxyadenosine) and isocordycepin (2′-deoxyadenosine) in 10 kinds of Cordyceps samples. The samples were prepared by ultrasonic extraction at 75 °C for 30 min with boiling water as the extraction solvent. The LC separation was performed on an Agilent poroshell 120 SB-Aq C18 column (3.0 × 50 mm, 2.7 μm) in isocratic mode with an eco-friendly mobile phase (2% ethanol containing 0.2% acetic acid) at a flow rate of 0.6 mL min−1, and detected by MS/MS in positive mode with multiple reaction monitoring (MRM). The developed method showed good linearity (r > 0.9990), sensitivity (LODs = 0.04 pg, LOQ = 0.1 pg), precision (RSD ≤ 3.8%) and stability (RSD ≤ 3.6%). The recoveries of developed method were 94.4–109.5% (RSD ≤ 5.5%). Compared with reported methods, the current method was rapid (less than 35% analytical time), sensitive (more than 5 folds), and eco-friendly (less than 10 μL harmful organic solvent). 10 different kinds of Cordyceps samples (40 batches) were tested by the developed method. Codycepin was only found in Cordyceps millitaris and C. millitaris fruiting body, and isocordycepin was detected in Cordyceps sinensis and other 6 Cordyceps samples. The developed method would be an improved method for the quality evaluation of Cordyceps samples.

Cordyceps mushroom with increased cordycepin content by the cultivation on edible insects

Cordycepin is the major constituent of Cordyceps mushroom (or Cordyceps militaris) with therapeutic potential. Insects are the direct sources of nutrients for Cordyceps in nature. Therefore, optimized condition of Cordyceps cultivation for efficient cordycepin production was explored using six edible insects as substrates. The highest yield of cordycepin was produced by the cultivation on Allomyrina dichotoma and was 34 times that on Bombyx mori pupae. Among insect components, fat content was found to be important for cordycepin production. Especially, a positive correlation was deduced between oleic acid content and cordycepin production. The transcriptional levels of cns1 and cns2, genes involved in cordycepin biosynthesis, were higher in Cordyceps grown on A. dichotoma than on other insects tested. The addition of oleic acid to the substrates increased cordycepin production together with the transcriptional levels of cns1 and cns2. Therefore, Cordyceps with high content of cordycepin can be secured by the cultivation on insects.

Efficient CRISPR/Cas9 system based on autonomously replicating plasmid with an AMA1 sequence and precisely targeted gene deletion in the edible fungus, Cordyceps militaris

Cordyceps militaris is a popular edible fungus with important economic value worldwide. In this study, an efficient CRISPR/Cas9 genome-editing system based on an autonomously replicating plasmid with an AMA1 sequence was constructed. Further, a precisely targeted gene deletion via homology-directed repair was effectively introduced in C. militaris. Gene editing was successful, with efficiencies of 55.1% and 89% for Cmwc-1 and Cmvvd, respectively. Precisely targeted gene deletion was achieved at an efficiency of 73.9% by a single guide RNA supplementation with donor DNAs. Double genes, Cmwc-1 and Cmvvd, were edited simultaneously with an efficiency of 10%. Plasmid loss was observed under non-selective culture conditions, which could permit recycling of the selectable marker and avoid the adverse effects of the CRISPR/Cas9 system on the fungus, which is beneficial for the generation of new cultivars. RNA Pol III promoters, endogenous tRNAPro of C. militaris, and chimeric AfU6-tRNAGly can be used to improve the efficiency. Polyethylene glycol-mediated protoplast transformation was markedly more efficient than Agrobacterium tumefaciens-mediated transformation of C. militaris. To our knowledge, this is the first description of genome editing and precisely targeted gene deletion in mushrooms based on AMA1 plasmids. Our findings will enable the modification of multiple genes in both functional genomics research and strain breeding.

The molecular recognition of cordycepin arabinoside and analysis of changes on cordycepin and its arabinoside in fruiting body and pupa of Cordyceps militaris

Cordyceps militaris is an edible fungus that is widely used as a functional food in many countries. In order to objectively evaluate its nutritional value, free and glycosidic cordycepins need to be analyzed. The cordycepin arabinoside molecule was recognized by the MS² fragmentation rule, and both cordycepin and its arabinoside were quantitatively analyzed in the fruiting body and pupa of Cordyceps militaris by high-performance liquid chromatography with tandem mass spectrometric (HPLC-MS/MS). The method had good linear regression (R² = 0.9999), with a detection limit of 0.021 ng/mL. The recovery range was 94.32-103.09% in the fruiting body and pupa. The content of cordycepin and its arabinoside showed an upward trend with growth, and the total contents reached the highest level at the mature stage (60-70th day) without mildew. This study provides a useful reference for the evaluation and application of Cordyceps militaris as a functional food resource.