Progress on Z genome biosynthetic pathway of bacteriophage.

There are abundant base modifications in bacteriophages' genomes, mainly for avoiding the digestion of host endonucleases. More than 40 years ago, researchers discovered that 2-amino-adenine (Z) completely replaced adenine (A) and forms a complementary pairing with three hydrogen bonds with thymine (T) in the DNA of cyanophage S-2L, forming a distinct "Z-genome". In recent years, researchers have discovered and validated the biosynthetic pathway of Z-genome in various bacteriophages, constituting a multi-enzyme system. This system includes the phage-encoded enzymes deoxy-2'-aminoadenylosuccinate synthetase (PurZ), deoxyadenosine triphosphate hydrolase (dATPase/DatZ), deoxyadenosine/deoxyguanosine triphosphate pyrophosphatase (DUF550/MazZ) and DNA polymerase (DpoZ). In this review, we provide a concise overview of the historical discovery on diversely modified nucleosides in bacteriophages, then we comprehensively summarize the research progress on multiple enzymes involved in the Z-genome biosynthetic pathway. Finally, the potential applications of the Z-genome and the enzymes in its biosynthetic pathway are discussed in order to provide reference for research in this field.

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.

Cordycepin Inhibits Virus Replication in Dengue Virus-Infected Vero Cells.

Dengue virus (DENV) infection causes mild to severe illness in humans that can lead to fatality in severe cases. Currently, no specific drug is available for the treatment of DENV infection. Thus, the development of an anti-DENV drug is urgently required. Cordycepin (3'-deoxyadenosine), which is a major bioactive compound in Cordyceps (ascomycete) fungus that has been used for centuries in Chinese traditional medicine, was reported to exhibit antiviral activity. However, the anti-DENV activity of cordycepin is unknown. We hypothesized that cordycepin exerts anti-DENV activity and that, as an adenosine derivative, it inhibits DENV replication. To test this hypothesis, we investigated the anti-DENV activity of cordycepin in DENV-infected Vero cells. Cordycepin treatment significantly decreased DENV protein at a half-maximal effective concentration (EC50) of 26.94 µM. Moreover, DENV RNA was dramatically decreased in cordycepin-treated Vero cells, indicating its effectiveness in inhibiting viral RNA replication. Via in silico molecular docking, the binding of cordycepin to DENV non-structural protein 5 (NS5), which is an important enzyme for RNA synthesis, at both the methyltransferase (MTase) and RNA-dependent RNA polymerase (RdRp) domains, was predicted. The results of this study demonstrate that cordycepin is able to inhibit DENV replication, which portends its potential as an anti-dengue therapy.

Effects of Cultured Cordycep militaris on Sexual Performance and Erectile Function in Streptozotocin-Induced Diabetic Male Rats.

Cordyceps militaris (CM), a valuable edible and medicinal fungus, has been used as traditional medicine to treat health conditions, as well as hyposexuality in Asian societies for over a century. Due to the high demand, several artificial cultivation methods have been developed for their biological activities. In this study, CM was cultured on medium that contained white rice and silkworm pupae, and the levels of cordycepin and adenosine, as well as its aphrodisiac effects in diabetes-induced erectile dysfunction (DIED), were evaluated. Diabetic rats were induced by streptozotocin (STZ) injection and administered orally with CM (0.1, 0.5, and 1.0 g/kg BW/day) for 3 weeks. Diabetic rats in negative and positive control groups received vehicle and sildenafil citrate (5 mg/kg), respectively. Results showed the changes in mating behaviour in which mount latency and intromission latency were significantly increased in diabetic rats, compared with the normal control group. Diabetic rats also showed a significant reduction in intracavernosal pressure (ICP) response to cavernous nerve stimulation, sperm count, testosterone level, penile nitric oxide synthase (NOS), and testicular superoxide dismutase (SOD) activities, when compared to the normal control group. Administration of CM (0.1, 0.5, and 1.0 g/kg BW/day) reversed the effects of diabetes on the mating behaviour, and the ICP responses to electrical stimulation. Moreover, the levels of penile NOS, testicular SOD activities, testosterone, and sperm count were significantly increased, and testicular malondialdehyde (MDA) levels were significantly decreased in these treated diabetic rats. Diabetic rats treated with sildenafil showed a significant induction in intromission frequency and NOS and SOD activities, as well as a marked increase in ICP responses. These results suggest that CCM exerts its aphrodisiac effect, possibly through activating testosterone production and suppressing oxidative stress to enhance erectile function in diabetic rats.

Cordycepin for Health and Wellbeing: A Potent Bioactive Metabolite of an Entomopathogenic Cordyceps Medicinal Fungus and Its Nutraceutical and Therapeutic Potential.

Cordyceps is a rare naturally occurring entomopathogenic fungus usually found at high altitudes on the Himalayan plateau and a well-known medicinal mushroom in traditional Chinese medicine. Cordyceps contains various bioactive components, out of which, cordycepin is considered most vital, due to its utmost therapeutic as well as nutraceutical potential. Moreover, the structure similarity of cordycepin with adenosine makes it an important bioactive component, with difference of only hydroxyl group, lacking in the 3' position of its ribose moiety. Cordycepin is known for various nutraceutical and therapeutic potential, such as anti-diabetic, anti-hyperlipidemia, anti-fungal, anti-inflammatory, immunomodulatory, antioxidant, anti-aging, anticancer, antiviral, hepato-protective, hypo-sexuality, cardiovascular diseases, antimalarial, anti-osteoporotic, anti-arthritic, cosmeceutical etc. which makes it a most valuable medicinal mushroom for helping in maintaining good health. In this review, effort has been made to bring altogether the possible wide range of cordycepin's nutraceutical potential along with its pharmacological actions and possible mechanism. Additionally, it also summarizes the details of cordycepin based nutraceuticals predominantly available in the market with expected global value. Moreover, this review will attract the attention of food scientists, nutritionists, pharmaceutical and food industries to improve the use of bioactive molecule cordycepin for nutraceutical purposes with commercialization to aid and promote healthy lifestyle, wellness and wellbeing.

Mechanism of Activation of AMPK by Cordycepin.

Cordycepin (3'-deoxyadenosine) is a major bioactive agent in Cordyceps militaris, a fungus used in traditional Chinese medicine. It has been proposed to have many beneficial metabolic effects by activating AMP-activated protein kinase (AMPK), but the mechanism of activation remained uncertain. We report that cordycepin enters cells via adenosine transporters and is converted by cellular metabolism into mono-, di-, and triphosphates, which at high cordycepin concentrations can almost replace cellular adenine nucleotides. AMPK activation by cordycepin in intact cells correlates with the content of cordycepin monophosphate and not other cordycepin or adenine nucleotides. Genetic knockout of AMPK sensitizes cells to the cytotoxic effects of cordycepin. In cell-free assays, cordycepin monophosphate mimics all three effects of AMP on AMPK, while activation in cells is blocked by a γ-subunit mutation that prevents activation by AMP. Thus, cordycepin is a pro-drug that activates AMPK by being converted by cellular metabolism into the AMP analog cordycepin monophosphate.

A rapid assay to screen adenosine deaminase inhibitors from Ligustri Lucidi Fructus against metabolism of cordycepin utilizing ultra-high-performance liquid chromatography-tandem mass spectrometry.

Cordycepin has recently received increased attention owing to its extensive pharmacological activity. Adenosine deaminase (ADA) is widely distributed in mammalian blood and tissues; as a result, cordycepin is quickly metabolized upon entering into the body and converted into the inactive metabolite 3'-deoxyinosine, thus limiting its activity when administered alone. We herein present a novel ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method for screening ADA inhibitors against the metabolism of cordycepin. Cordycepin and 3'-deoxyinosine were chosen as substrate and product, respectively. A proper separation was achieved for all analytes within 3 min. 3'-Deoxyinosine was quantified in the presence or absence of potential ADA inhibitors to evaluate ADA activity. The assay can simultaneously determine substrate and product, with the endogenous substance and ADA inhibitors added not interfering in its activity. After optimizing the enzymatic incubation and UHPLC-MS/MS conditions, Km and Vmax values for ADA deamination of cordycepin were 95.18 ± 7.85 µm and 363.90 ± 12.16 µmol/min/unit, respectively. Oleanolic acid and ursolic acid from Ligustri Lucidi Fructus were chosen as ADA inhibitors with half maximal inhibitory concentration values of 21.82 ± 0.39 and 18.41 ± 0.14 µm, respectively. A non-competitive inhibition model was constructed and this assay can be used to screen other potential ADA inhibitors quickly and accurately.

Therapeutic Potential and Biological Applications of Cordycepin and Metabolic Mechanisms in Cordycepin-Producing Fungi.

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.

Selenium Biofortification and Antioxidant Activity in Cordyceps militaris Supplied with Selenate, Selenite, or Selenomethionine.

Selenium (Se) is an essential trace element with multiple functions that may help mitigate adverse health conditions. Cordyceps militaris is an edible mushroom with medicinal properties. The experiment was conducted under artificial cultivation, with five Se concentrations (0, 5, 10, 20, and 40 µg g-1) and three forms of Se (selenate, selenite, and selenomethionine). C. militaris can absorb inorganic from the substrate and convert it to organic Se compounds (selenocystine, selenomethionine, and an unknown species) in fruiting bodies. Compared with the control treatment, Se applications (40 µg g-1 selenate and selenite) significantly increased the Se concentration in fruiting bodies by 130.9 and 128.1 µg g-1, respectively. The biofortification with selenate and selenite did not affect fruiting body production, in some case, but did enhance the biological efficiency. Moreover, the abundance of cordycepin and adenosine increased, while the amino acid contents remained relatively stable. Meanwhile, Se-biofortified C. militaris showed effective antioxidant activities. These results suggest that Se-biofortified C. militaris fruiting bodies may enhance human and animal health when it was included as part of a healthy diet or used as Se supplements.

Immune-enhancing activity of C. militaris fermented with Pediococcus pentosaceus (GRC-ON89A) in CY-induced immunosuppressed model.

BACKGROUND: Cordyceps militaris (C. militaris) is reported to exert various immune-activities. To enhance its activity, we fermented C.militaris with Pediococcus pentosaceus ON89A (GRC-ON89A). In this study, we investigated the immune-enhancing activity GRC-ON89A, using immunosuppressed model. METHODS: Immunosuppression was induced by intraperitoneal injection of cyclophosphamide (CY). Each group was orally administered distilled water, GRC-ON89A or GRC, respectively. The phagocytic activities against IgG -opsonized FITC particles were measured using phagocytosis assay kit. The contents ß-glucan, cordycepin and SCFA were measured using ß-glucan kit, liquid chromatography-mass spectrometry analysis and Gas chromatography-mass spectrometry analysis, respectively. RESULTS: Among GRC fermented with different probiotic strains (Pediococcus pentossaceus ON89A, Lactobacillus pentosus SC64, Weissella cibaria Sal.Cla22), GRC-ON89A induced the highest elevation of nitric oxide production and enhanced phagocytic activity of RAW 264.7 cells. In primary cultured murine macrophages from normal and CY-treated mice, GRC-ON89A increased phagocytic activity, compared to that in control cells. GRC-ON89A also significantly induced the mRNA expression of TNF-α and IL-10 and the levels of phosphorylated Lyn, Syk and MAPK. The contents of ß-glucan, cordycepin and SCFA in GRC significantly increased after ON89A fermentation, compared to those in unfermented GRC. CONCLUSION: These results indicate that GRC-ON89A exerted the enhanced immunostimulatory activity and contained more nutritional components, compared to unfermented GRC. Our results suggested that GRC-ON89A may be applied as an agent for immune boosting therapy in immune suppressed patients.

A Novel Technique for Rejuvenation of Degenerated Caterpillar Medicinal Mushroom, Cordyceps militaris (Ascomycetes), a Valued Traditional Chinese Medicine.

Cordyceps militaris has been used in traditional Chinese medicine for many years, but its frequent degeneration during continuous maintenance in culture can lead to substantial commercial losses. In this study, a degenerated strain of C. militaris was obtained by subculturing a wild-type strain through 10 successive subcultures. The relative abundance of the 2 mating types seems to be out of balance in the degenerated strain. By cross-mating 4 single-ascospore isolates (2 for MAT 1-1 and 2 for MAT 1-2) from the degenerated strain, we were able to restore fruiting body production to wild-type levels. The rejuvenated strain not only produced well-developed fruiting bodies but also accumulated more cordycepin and adenosine than either the original wild-type strain or the degenerated strain. These new characteristics remained stable after 4 successive transfers, which indicates that the method used to rejuvenate the degenerated strain in this study is an effective approach.

Effect of UV-B Irradiation on Physiologically Active Substance Content and Antioxidant Properties of the Medicinal Caterpillar Fungus Cordyceps militaris (Ascomycetes).

Ultraviolet-B (UV-B) light irradiation is a well-known technique for converting vitamin D2 from ergosterol in mushroom fruit bodies. Mushrooms are a natural and nonanimal food source of vitamin D2. We studied the effect of UV-B light irradiation on the amount of vitamin D2 and physiologically active substances in Cordyceps militaris and their antioxidant properties. After UV-B irradiation for 2 hours, the vitamin D2 content of freshly harvested C. militaris fruiting bodies, mycelia, whole submerged culture (WSC), and homogenized submerged culture (HSC) increased from 0 to 0.03 to 0.22 to 1.11 mg/g, but the ergosterol content was reduced from 1.36 to 2.50 to 1.24 to 2.06 mg/g, respectively. After UV-B irradiation, the amount of adenosine, cordycepin, and ergothioneine of fruiting bodies dramatically increased 32-128%, but the polysaccharide content slightly decreased 36%. The reverse trends were observed in mycelia, WSC, and HSC. UV-B irradiation could reduce the effective concentrations at 50% of fruiting bodies for ethanolic and hot water extracts in reducing power, scavenging, and chelating abilities, whereas mycelia, WSC, and HSC of ethanolic extracts increased effective concentrations at 50% in reducing power, scavenging, and chelating abilities. UV-B irradiation slightly increased flavonoid content (10-56%) and slightly affected total phenol content.

Cordycepin and N6-(2-hydroxyethyl)-adenosine from Cordyceps pruinosa and their interaction with human serum albumin.

Cordyceps pruinosa (CP) is often used as Traditional Chinese Medicine, but the substance basis of its medicinal properties is unclear. In this study, two compounds were isolated from CP cultures by column chromatography, and identified as cordycepin and N6-(2-hydroxyethyl)-adenosine (HEA) by Nuclear Magnetic Resonance. In order to understand the efficacy of these two substances as potential therapeutic agents, it is necessary to explore their binding with proteins. The molecular mechanisms of interaction between cordycepin, HEA and human serum albumin (HSA) were studied using UV and fluorescence spectroscopy. The bingding constants between HSA and cordycepin were 4.227, 3.573 and 3.076 × 10(3)·at 17, 27 and 37°C respectively, and that of HSA and HEA were 27.102, 19.409 and 13.002 × 10(3)·at the three tempretures respectively. Both cordycepin and HEA can quench the intrinsic fluorescence of HSA via static quenching, and they can bind with HSA to form complexes with a single binding site. The interaction forces between cordycepin and HSA were determined as electrostatic and hydrophobic, and those of HEA and HSA were hydrogen bonding and van der Waals forces. Using Foster's equation, the distance between fluorophores of cordycepin and HSA, and HEA and HSA are estimated to be 5.31 nm and 4.98 nm, respectively. In this study, cordycepin was isolated for the first time from CP, and will provide a new source of cordycepin and expand the use of this taxon. The interaction mechanisms between cordycepin and HSA was studied for the first time, which will provide a useful guide for the clinical application of cordycepin. The pharmacological importance of this study is to understand the interaction of HSA with cordycepin and HEA, which will be essential for the future designing of drugs based on the two compounds.

Cordyceps s.l. (Ascomycetes) Species Used as Medicinal Mushrooms are Closely Related with Higher Ability to Produce Cordycepin.

Cordyceps s.l. (sensu lato) species have been used as herbal medicines; one of their main constituents is cordycepin. As genome sequencing techniques have become more cost-effective and more popular, more entomogenous fungal genomes have been sequenced and published. Here, we constructed a phylogenetic tree based on 18S rRNA sequences from Cordyceps species and analyzed the copy number of the key enzymes involved in biosynthesis of cordycepin from related fungal genomes that have been published. The sequences of the 18S rRNA gene were examined, and seven single nucleotides were found that could represent the evolutionary history of Cordyceps s.l. and which perfectly fit the phylogenetic tree. Their evolution was influenced mainly by host factors, rather than geographical location. The Cordyceps s.l. species that are used as herbal medicines are closely related in the phylogenetic tree. The major species for Chinese pharmaceutical markets, such as C. militaris and C. sinensis, have higher copy numbers of 5'-nucleotidase and adenylate kinase, and ribonucleotide reductases (RNRs), respectively. Moreover, absence of an RNR inhibitor may cause cordycepin accumulation. Presence of an RNR inhibitor may lead to lower cordycepin levels in fungal species in which no medicinal applications have been described. Cordycepin is not only an important secondary metabolite that is used as an herbal medicine, but it also has significance for understanding the evolution of these entomogenous species.

Various grain substrates for the production of fruiting bodies and bioactive compounds of the medicinal caterpillar mushroom, Cordyceps militaris (Ascomycetes).

In this study, several grains such as brown rice (Br), plumule rice (Pr), wheat (W) and pearl barley (Pb) supplemented with 1% (w/w) peptone (P), yeast extract (Ye), ammonia sulfate (As), and monosodium glutamate (Mg) as a nitrogen source, respectively, were used to produce fruiting bodies and bioactive compounds of two strains of Cordyceps militaris. Among these grain substrates, the substrate most suitable to mycelial growth was Pb+Ye for C. militaris H and L. The mushroom strains colonized this substrate in 12.8 and 12.6 days, respectively. For C. militaris L, the fewest days were required for primordial initiation on Br+Ye and Pr+P substrates. The highest yield and biological efficiency was observed with Pb substrate (25.16 g/bottle and 87.36%) and Br+P substrate (21.84 g/bottle and 75.83%) for C. militaris H and L, respectively. In the fruiting bodies of C. militaris H, the highest cordycepin content was cultivated on W+Mg substrate (25.07 mg/g), the highest mannitol content was cultivated with Pr+Mg (153.21 mg/g) and Pr (151.65 mg/g) substrates, and the highest adenosine content was cultivated with Pr+Ye (0.94 mg/g) and Pb+Ye (0.90 mg/g) substrates. In the fruiting bodies of C. militaris L, the highest cordycepin content was cultivated with W+Mg substrate (22.14 mg/g); the highest mannitol content was cultivated with Pb substrate (189.33 mg/g); and the highest adenosine content was cultivated with Pb+Ye substrate (0.71 mg/g).

Cultivation of medicinal caterpillar fungus, Cordyceps militaris (Ascomycetes), and production of cordycepin using the spent medium from levan fermentation.

A process of tandem cultivation for the production of green and invaluable bioproducts (levan and Cordycepes militaris) useful for medical applications has been successfully developed. The process involves first cultivating Bacillus subtilis strain natto in sucrose medium to produce levan, followed by the subsequent cultivation of C. militaris in liquid- and solid-state cultures using the spent medium from levan fermentation as substrates. The factors affecting the cell growth and production of metabolites of C. militaris were investigated, and the various metabolites produced in the culture filtrate, mycelia, and fruiting body were analyzed. In addition, cordycepin was prepared from the solid waste medium of C. militaris. This is an excellent example in the development of cost effective biorefineries that maximize useful product formation from the available biomass. The preparation of cordycepin from solid waste medium of C. militaris using a method with high extraction efficiency and minimum solvent usage is also environmentally friendly.

Optimization of solid state culture conditions for the production of adenosine, cordycepin, and D-mannitol in fruiting bodies of medicinal caterpillar fungus Cordyceps militaris (L.:Fr.) Link (Ascomycetes).

In general, Cordyceps sinensis is much more popular than C. militaris, though both species contain quite similar bioactive ingredients and exhibit medicinal activities. Many bioactive ingredients have been isolated from C. militaris, such as adenosine, cordycepin, D-mannitol, and exopolysaccharides. C. militaris is claimed to have extensive pharmacological properties, such as: anti-inflammatory; anti-fatigue; anti-bacterial; anti-diabetic; improve lung, liver, and kidney functions; to be beneficial for treating cancer as well as male and female sexual dysfunctions. C. militaris is fast gaining momentum for its so-called health benefits, and it is often used as a substitute for C. sinensis. In view of the growing popularity of C. militaris, nowadays C. militaris cultivation for stroma is also done. There is a great diversity of compounds from different strains of Cordyceps and different artificially cultivated products. This study is to determine the optimum culture parameters integrated with substrate of choice to bring the indoor-cultivated C. militaris to a higher and more consistent level of quality. To achieve the above objective, the resultant products after growth were analyzed for adenosine, cordycepin, and D-mannitol using the high-performance liquid chromatography method. The optimum culture condition to produce a high level of adenosine is by using millet as solid substrate. It must be cultivated in the dark for the first 7 days and harvested on day 40. The optimum culture condition to produce a high level of cordycepin is by using soybean as solid substrate. It must be cultivated in the dark for the first 14 days and harvested on day 50. While a high level of D-mannitol is achieved with millet as the solid substrate. It must be kept in the dark for the first 7 days and harvested on day 50. The adenosine level decreased and cordycepin increased from day 40 of culture to day 50 generally.

Effects of selenium and light wavelengths on liquid culture of Cordyceps militaris Link.

To investigate the effects of selenium and light wavelengths on the growth of liquid-cultured Cordyceps militaris and the main active components' accumulation, culture conditions as selenium selenite concentrations and light of different wavelengths were studied. The results are: adenosine accumulation proved to be significantly selenium dependent (R(2) = 0.9403) and cordycepin contents were determined to be not significantly selenium dependent (R(2) = 0.3845) but significantly enhanced by selenium except for 20 ppm; there were significant differences in cordycepin contents, adenosine contents, and mycelium growth caused by light wavelengths: cordycepin, blue light > pink light > daylight, darkness, red light; adenosine, red light > pink light, darkness, daylight, blue light; and mycelium growth, red light > pink light, darkness, daylight > blue light. In conclusion, light wavelength had a significant influence on production of mycelia, adenosine, and cordycepin, so lightening wavelength should be changed according to target products in the liquid culture of C. militaris.

Recycling of methylthioadenosine is essential for normal vascular development and reproduction in Arabidopsis.

5'-Methylthioadenosine (MTA) is the common by-product of polyamine (PA), nicotianamine (NA), and ethylene biosynthesis in Arabidopsis (Arabidopsis thaliana). The methylthiol moiety of MTA is salvaged by 5'-methylthioadenosine nucleosidase (MTN) in a reaction producing methylthioribose (MTR) and adenine. The MTN double mutant, mtn1-1mtn2-1, retains approximately 14% of the MTN enzyme activity present in the wild type and displays a pleiotropic phenotype that includes altered vasculature and impaired fertility. These abnormal traits were associated with increased MTA levels, altered PA profiles, and reduced NA content. Exogenous feeding of PAs partially recovered fertility, whereas NA supplementation improved fertility and also reversed interveinal chlorosis. The analysis of PA synthase crystal structures containing bound MTA suggests that the corresponding enzyme activities are sensitive to available MTA. Mutant plants that expressed either MTN or human methylthioadenosine phosphorylase (which metabolizes MTA without producing MTR) appeared wild type, proving that the abnormal traits of the mutant are due to MTA accumulation rather than reduced MTR. Based on our results, we propose that the key targets affected by increased MTA content are thermospermine synthase activity and spermidine-dependent posttranslational modification of eukaryotic initiation factor 5A.

S-Adenosylmethionine regulates connexins sub-types expressed by hepatocytes.

Intercellular communication via GAP Junctions plays an important role in tissue homeostasis, apoptosis, carcinogenesis, cell proliferation and differentiation. Hepatocyte connexins (Cx) 26 and 32 levels are decreased during the de-differentiation process of primary hepatocytes in culture, a situation that is also characterized by a decrease in S-Adenosylmethionine (SAMe) levels. In this current study, we show that SAMe supplementation in cultured hepatocytes every 12h, leads to an up-regulation of Cx26 and 32 mRNA and protein levels and blocks culture-induced Cx43 expression, although it failed to increase Cx26 and 32 membrane localization and GAP junction intracellular communication. SAMe reduced nuclear ß-catenin accumulation, which is known to stimulate the TCF/LEF-dependent gene transcription of Cx43. Moreover SAMe-induced reduction in Cx43 and ß-catenin was prevented by the proteasome inhibitor MG132, and was not mediated by GSK3 activity. SAMe, and its metabolite 5'-methylthioadenosine (MTA) increased Cx26 mRNA in a process partially mediated by Adenosine A(2A) receptors but independent of PKA. Finally livers from MAT1A knockout mice, characterized by low hepatic SAMe levels, express higher Cx43 and lower Cx26 and 32 protein levels than control mice. These results suggest that SAMe maintains a characteristic expression pattern of the different Cxs in hepatocytes by differentially regulating their levels.