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Does the fact cordyceps mostly affect insects have something to do with chitin being polysaccharide?

Does the fact cordyceps mostly affect insects have something to do with chitin being polysaccharide?



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This is just a conjecture of mine based on those observations:

  • Fungus seems to be very good at attacking tough chains of sugars like cellulose and starch.
  • insects are covered by Chitin, a polysaccharide.
  • cordyceps only attacks arthropods and in rare instances other fungus. Both arthropods and fungus have chitin in their body.

My initial guess was no but there might actually be some evidence for this. For example, host-switching between fungus and insects apparently happens within relatively small taxa of cordyceps, suggesting that host specialization is not too dramatic.

Moreover, there does seem to be some evidence that chitin is a relatively important metabolic input for at least one cordyceps species.

I don't know that we could say that chitin is the thing that allows the host switching or that it is the most important nutrient for cordyceps or anything like that, but it looks like it at least helps.

It's worth noting that ecological characteristics may play at least as large of a role. The phylogenetic study noted that host switching likely occurred from cicada nymphs (which hibernate underground) to truffles (which have their main mass underground), so it's possibly just an opportunistic jump in the soil environment.

It would be interesting to see if there is a "chitin sensor" mechanism in cordyceps that yields a signal to cordyceps that there is a host to invade. But I don't think that I saw anything that suggests that (though it's far from unprecedented in biology).


13 Advantages and Disadvantages of Exoskeletons

An exoskeleton is an external covering for the body that can be found in some invertebrate animals. It is most commonly seen with arthropods, giving them support and protection as they go about their daily living activities. Machine-based exoskeletons are also available to provide human-based supports that offer a similar set of benefits.

The exoskeleton contains a rigid and resistant set of components that fill functional roles to protect, sense, and support the creature. It also offers a defensive mechanism against pests or predators, providing an extra layer of help through an attachment framework to the animal’s musculature.

Most exoskeletons contain chitin, calcium, and carbonate to give this structure the remarkable strength it provides. The material is about six times stronger and twice as stiff when compared to the tendons of the vertebrate. It is a function that has experienced independent evolution numerous times, with almost 20 different calcified versions alone. Although they provide several purposes, they can also reduce the movement of the animal.

That’s why biologists look at the advantages and disadvantages of an exoskeleton in the following light.

List of the Advantages of an Exoskeleton

1. An exoskeleton allows for complex movements because of jointed appendages.
An exoskeleton is the thick covering that you can find on the outside of some animals. The design of this defensive layer often comes with flexible joints that work with the creature’s underlying muscles. It is a benefit that allows for a wide range of movements for the animal, and it is ultimately the opposite of how humans are put together with their endoskeleton.

Grasshoppers, scorpions, and shrimp are all examples of animals that contain this feature. Most insects have several segments that make it look like each body part receives coverage from a separate piece of their exoskeleton. This design is what makes it possible for the head and body parts to separately move.

2. It protects an animal against abrasion or physical damage.
An exoskeleton provides an exceptional protective covering for an animal’s muscles and soft internal organs. Creatures that do not have this protection are more vulnerable to injuries that impact their soft tissues. The material of this defensive layer can be made from bone or a combination of other elements so that it always maximizes the potential of this advantage. That means the animal can go almost anywhere within its habitat without worrying about the consequences of that decision.

3. This structure increases the leverage of the animal.
An exoskeleton is typically made up of several layers. You will have a hard outer surface and a flexible inner layer working together to provide a significant amount of protection against predators. There’s a waxy surface on the innermost layer that protects the animal against dehydration. Most arthropods have a secondary layer that prevents this first one from getting torn or damaged.

This structure gives the animal a lot of leverage in a variety of ways. It can control its habitat, use the outer layer as a shield or weapon, or even have it as a tool that can make life more comfortable in a variety of ways.

4. Exoskeletons prevent dehydration or getting too wet.
The hard covering on the outside of this structure helps to support the body of the animal in a manner that is similar to wearing a portable raincoat. It will prevent the creature from drying out with its flexible inner layers while stopping the animal from getting too wet to function. That means there is a natural layer of defense against long spells of heat or cold. It is easier to maintain the overall perspective of health because of this protective shield. That’s why it is such an excellent survival strategy.

5. The frequency of molting is under hormonal control.
The stages that occur between molts for arthropods are referred to as instars. This time is when the actual tissue growth occurs for the creature, although it won’t expand in size until after the next molt occurs. Ecdysone controls this process, and it is the hormonal control that dictates the frequency of a new defensive layer forming.

Once the cuticle of the exoskeleton weakens through the enzymatic processes, the animal crawls out. Then it will suck in water or air to inflate the new exoskeleton so that the hardening process starts.

6. It removes the need for a hydrostatic skeleton.
Body plans can diversify within the structures of an exoskeleton, which means that the evolutionary processes can expand because of this support structure. That makes it easier for the animals to adapt to their changing environments as time passes, which is why this structure is the most successful one currently known to biologists. Many of the earliest animals that we know of on our planet used it, and this approach is still widely used by nature today.

Although chitin exoskeletons are quite heavy and place a constraint on the size of the animal, there is better leverage for moving limb muscles when compared to the processes used by an endoskeleton.

7. Exoskeletons promote a high level of diversity.
Arthropods are the most diverse group of organisms when researchers look at most ecosystems. Studies that looked at Canadian biodiversity specifically found that as early as 1994, there were up to 8,0900 different species in a single peatland habitat common to the country’s boreal forests. Because the outer skeleton provides more room for internal development and evolution, there is a strong likelihood that there are thousands of additional species out there in the world that we know nothing about yet.

Arthropods cover several size classes, exist in several environments, and have dispersal abilities. They work to maintain soil structures and fertility while regulating the populations of other organisms. It could be argued that these creatures are the most essential component of the global ecosystem.

List of the Disadvantages of an Exoskeleton

1. Exoskeletons don’t stretch or expand.
An exoskeleton is unable to take the same amount of shock that a soft tissue outer layer can withstand. Animals that are close to their molting time can face life-threatening consequences if an impact is severe enough. If a crack or injury does occur, then the healing process is a lot slower with this natural structure. If a fissure develops, then it may never heal at all.

This problem can end up causing a clot that threatens the life of the animal. The only way to thoroughly heal after this outer structure gets damaged is to replace it entirely through the molting process.

2. Special modifications are necessary for sensory pickup.
The thick outer layer of the exoskeleton makes it challenging for the animal to have sensory perception if their surrounding environment. It creates a structure that’s too hard to feel anything except pressure or significant impacts. This problem can put the creature into dangerous situations at times without their knowledge because the dangerous circumstances are above their protective features.

3. It can sometimes interfere with breathing without accommodations.
If an animal is approaching the time it is supposed to molt, then the pressure that their body places on the exoskeleton can interfere with their breathing. This disadvantage is also present when there are significant moisture levels in the creature’s habitat. Unless the natural processes get started to rectify the situation, there could be health concerns with this problem that are problematic enough to put its life in danger.

4. An exoskeleton provides a significant restriction on growth.
An exoskeleton is a substantial body component that would be unmanageable if an animal were to grow too large. That’s why the majority of the creatures that have this protective feature are typically small. It would be almost impossible for any movement to occur for a larger animal with an equitable protective layer. Most of the examples in nature are of insects or beetles because they don’t experience the size restrictions that a bear or a Tiger would have in the same circumstances.

5. Animals must shed the item at regular intervals if it doesn’t grow with them.
Unless the exoskeleton of the animal grows with it, molting is a significant disadvantage of this natural feature. Arthropods become highly vulnerable to predators during this time of growth because the new surface starts out soft and requires an extensive amount of time to harden. Until there is a complete restoration of the outer protective layer, the animal has almost no protection at all.

The molting process is so dangerous for some animals that it must remain in a safe and static environment to prevent life-changing threats from impacting it. Bacteria, mites, or fungal spores can easily penetrate an animal going through the moiling process.

6. Molting an exoskeleton means the animal cannot eat.
Tarantulas encounter unique challenges during the molting process. If the animal tries to eat before the exoskeleton completes its hardening, then the fangs and claws can get bent out of shape. It would leave the creature in a state where it wouldn’t be able to eat at all. Bone-based exoskeletons don’t encounter this issue except at birth, although the calcified nature of the structure can break like an arm or a leg.

Pros and Cons of Mechanical Exoskeletons to Consider

Mother Nature might be the designer of the world’s first exoskeletons, but humanity is following close behind in her footsteps. More factories, distribution centers, and warehouse operations are adding this technology to their services. Companies and workers use these devices to increase safety without compromising internal productivity levels.

Exoskeletons are wearable devices that a person places on their body to reinforce, augment, or restore performance. This technology can be made from plastic parts, carbon fiber, or various metals. It works to prevent musculoskeletal disorders in workers that could cost an organization millions of dollars annually. Employees that get to use this technology complain of less shoulder and back pain while still being more physically active than without it.

Exoskeletons have the option to transfer the weight of a user’s arms from the shoulders and upper body to that person’s core. This action reduces the amount of physical stress that gets placed on the body during cumbersome lifting processes. Although humans carry some of the weight of the objects being transferred when using this technology, it can increase individual durability and improve movement.

The fossil record only contains mineralized exoskeletons. Since these are more durable than the type found on arthropods, this evidence makes sense. That fact makes it challenging to look at the history and evolution of nature’s approach to this protective mechanism, although we do know that just before the Cambrian Period, there were phosphate, calcite, aragonite, and silica examples in nature.

Exoskeletons provide animals with a critical amount of protection so that they aren’t immediately vulnerable to predators. Although it presents particular challenges to the creature during their molting stage, it is something that’s easily managed in most circumstances.

As we look at all of the advantages and disadvantages of an exoskeleton, it is easy to see what it’s such an active evolutionary component. It stops predators, leverages muscle movements, and offers several additional benefits that often outweigh the issues involved.


Abstract

Traditional Chinese medicines (TCM) are growing in popularity. However, are they effective? Cordyceps is not studied as systematically for bioactivity as another TCM, Ganoderma. Cordyceps is fascinating per se, especially because of the pathogenic lifestyle on Lepidopteron insects. The combination of the fungus and dead insect has been used as a TCM for centuries. However, the natural fungus has been harvested to the extent that it is an endangered species. The effectiveness has been attributed to the Chinese philosophical concept of Yin and Yang and can this be compatible with scientific philosophy? A vast literature exists, some of which is scientific, although others are popular myth, and even hype. Cordyceps sinensis is the most explored species followed by Cordyceps militaris. However, taxonomic concepts were confused until a recent revision, with undefined material being used that cannot be verified. Holomorphism is relevant and contamination might account for some of the activity. The role of the insect has been ignored. Some of the analytical methodologies are poor. Data on the “old” compound cordycepin are still being published: ergosterol and related compounds are reported despite being universal to fungi. There is too much work on crude extracts rather than pure compounds with water and methanol solvents being over-represented in this respect (although methanol is an effective solvent). Excessive speculation exists as to the curative properties. However, there are some excellent pharmacological data and relating to apoptosis. For example, some preparations are active against cancers or diabetes which should be fully investigated. Polysaccharides and secondary metabolites are of particular interest. The use of genuine anamorphic forms in bioreactors is encouraged.


Adaptogenic

Cordyceps is what's known as an Adaptogen, this means it belongs to a group of medicinal plants & mushrooms that have a non-specific, wide-range of medicinal properties. Adaptogens also help the body to form greater resistance to stress & anxiety while having a normalizing effect on the body. You can expect a future post on this subject.

(Adaptogens are generally non-toxic and have been safely used for health & wellness and to increase human vitality for thousands of years. This image does not show all adaptogens.)


Molecular studies of genes isolated from Cordyceps sp.

It is necessary to understand the genetic makeup and molecular biology of Cordyceps not only to enhance the production of Cordycepin and exopolysaccharides but also to figure out the biochemical synthetic pathway of the above bio-metabolites. Cordycepin and exopolysaccharides are some of the major pharmacologically active constituents of Cordyceps. There exists a variety of valuable genes encoding enzymes isolated and subsequently cloned from this medicinally important insect fungus. Isolation and cloning of FKS1 gene has been carried out successfully from Cordyceps which encodes for an integral membrane protein acting as a catalytic subunit for enzyme β-1,3 glucan synthase and responsible for the biosynthesis of a potent immunological activator, i.e., β-glucan (Ujita et al. 2006). Another group isolated Cu, Zn SOD 1 gene (SOD 1) from Cordyceps militaris which not only acts as an anti-oxidant and anti-inflammatory agent but also neutralizes free radicals which could be a potential anti-aging drug (Park et al. 2005). From Cordyceps sinensis, two cuticle degrading serine protease genes, i.e., csp 1 and csp 2 have been cloned and expressed in yeast Pichia pastoris. The genes, csp1 and csp 2 were further characterized using synthetic substrate N-suc-AAPF-p-NA to understand the pathobiology and infection to the host (Zhang et al. 2008). Similar studies were carried out to clone and analyse glyceraldehyde-3-phosphate-dehydrogenase (GPD) gene from Cordyceps militaris. GPD is an important enzyme used in the glycolytic pathway, which catalyses the phosphorylation of glyceraldehyde-3-phosphate to form 1, 3-diphosphoglycerate, an important reaction to maintain life activities in a cell for the generation of ATP (Gong et al. 2009). Further studies could be directed toward improving Cordyceps sp. by developing an effective transformation system.


Discussion

Chitinases are present in high concentrations in cereal grains known to be nontoxic to plants and higher vertebrates whereas they are toxic to plant pathogens such as insects and fungi. Transgenic plants expressing an insect chitinase gene have shown enhanced resistance to insect feeding in many studies. This is because of its capacity to degrade the linear polymer of chitin consisting of β-1,4-linked N-acetylglucosamines, which is an integral part of insect cuticle and PM. Hence transgenic crop overexpressing the insect chitinase are protected from the pathogenic fungi and pest insects. First studies that evaluated insect resistance of transgenic plants expressing an insect chitinase utilized transgenic tobacco plants and European corn borer 26,27 . In this study, the expression level of insect chitinase was found to be low, but even then the mortality rate of European corn borer was found significant when compared with the wild type. However no significant mortality was observed on M. sexta larva feeding on same transgenic tobacco line. The reason for this was attributed to the thickness of PM in case of M. sexta compared to European corn borer. In another study, transgenic papaya lines expressing the M. sexta chitinase gene showed significant tolerance to spider mites under field conditions 28 . On the other hand, transgenic potato plants expressing a chitinase from the coleopteran pest, Phaedon cochleariae revealed slightly positive effects on population growth of the aphid M. persicae 29,30 . This can be explained by the absence of the PM in aphids, which rendered the transgenic chitinase to be ineffective to the aphid population. This shows the limitation of chitinase based transgenic crop against the insects as an oral insecticide.

As the previous studies have demonstrated positive insecticidal effects of chitinase, it is important to include this strategy for generating the transgenic maize resistant to insects. Maize production is damaged by insects, due to which we need to improve resistance management strategies by developing transgenic lines of commonly cultivated maize varieties with resistance to most of the insects as well as fungi. Biological control of some soil born fungal diseases has been correlated with chitinase production. Bacteria-producing chitinases and or glucanases exhibit antagonism in-vitro against fungi [inhibition of fungal growth by plant chitinases and dissolution of fungal cell walls by a streptomycete chitinase and p-(1,3)-glucanase have been demonstrated]. The importance of chitinase activity was demonstrated by the loss of biocontrol efficacy in Sewatia marcescens mutants in which the chiA gene had been inactivated 31 . Molecular techniques have also facilitated the introduction of beneficial traits into rhizosphere competent and model organisms to produce potential biocontrol agents. A recombinant Escherichia coli expressing the chiA gene from S. marcescens was effective in reducing disease incidence caused by Sclerotium rolfsii and Rhizoctonia solani 32 . In other studies, chitinase genes from S. marcescens have been expressed in Pseudomonas sp. and the plant symbiont Rhizobium meliloti. The modified Pseudomonas strain was shown to control the pathogens E oxysporum f. sp. redolens and Gauemannomyces graminis var. tritici 33 . Numerous plant chitinase genes or cDNAs have been cloned. In a successful case, transgenic tobacco plants were generated which constitutively expressed a bean endochitinase gene under the control of the cauliflower mosaic virus 35s promoter. The transgenic tobacco plants were less susceptible to infection by Rhizoctonia solani and either the disease development was delayed or they were not affected at all 34 . In conclusion, we have generated transgenic maize plant that overexpresses an insect chitinase. The chitinase cDNA from S. littoralis was isolated and transferred in different genotype of maize plant widely grown in Egypt. The expression of transgenic insect chitinase was observed and found to be overexpressed in regenerated transgenic maize. The insect resistance was also found to be significantly improved in the case of transgenic maize plant. This study is the first attempt to improve the maize productivity in Egyptian maize varieties so that farmers will get maximum benefits by protecting the crops in the field as well as during storage of grains.


Materials and Methods

Insect rearing

The planthoppers used in the present study were originally collected from a rice paddy field in Huaxi District, Guiyang City, Guizhou Province, China. Insects were reared in the laboratory of Guizhou University on the susceptible rice variety Taichung Native-1 (TN1) under controlled conditions of temperature 25 ± 2 °C, 70 ± 10% relative humidity (RH), and a 16 h:8 h (L:D) photoperiod. The developmental stages were synchronized at each egg incubation.

RNA extraction and cDNA cloning of SfCHS1

Total RNA was extracted from the whole body of fifth-instar nymphs of S. furcifera using TRIzol reagent (Invitrogen, Carlsbad, CA, USA). The integrity of total RNA was examined by 1% agarose gel electrophoresis, and a Nanodrop 2000 spectrophotometer (Thermo Fisher Scientific, Wilmington, DE, USA) was used to determine RNA concentration and purity. First-strand cDNA was synthesized from total RNA using an AMV First Strand cDNA Synthesis Kit (Sangon Biotech, Shanghai, China) with an oligodT primer, according to the user manual provided by the manufacturer.

On the basis of the transcriptome sequencing data (SRR116252) of S. furcifera 63 , four short cDNA sequences encoding SfCHS1 were identified. To obtain a larger cDNA fragment, six pairs of gene-specific primers (Table 1) were designed using Primer Premier 6.0 (Palo Alto, CA, USA). The ends were amplified by 3′- and 5′-RACE using a SMARTer RACE Kit following the manufacturer’s instructions (Clontech, Mountain View, CA, USA). PCR amplifications were carried out using LA Taq ® polymerase (TaKaRa, Dalian, China) in 25-μL reaction mixtures containing 2 μL dNTP (2.5 mM), 2.5 μL 10 × LA PCR Buffer (Mg 2+ plus), 1 μL each primer (10 mM), and l μL cDNA templates. The thermal cycling conditions were as follows: one cycle of pre-denaturation at 94 °C for 3 min, followed by 30 cycles of denaturation at 94 °C for 30 s, annealing at 50–55 °C (according to primer annealing temperature) for 30 s, and extension at 72 °C for 1–2 min (according to amplified fragment size), with a final extension at 72 °C for 10 min. The amplified products were examined by 1% agarose gel electrophoresis, and the target band of products was purified using an EasyPure ® Quick Gel Extraction Kit (Transgen Biotech, Beijing, China). Purified DNA was cloned into a pMD18-T vector (TaKaRa, Dalian, China) and sequenced by Sangon Biotech (Shanghai, China).

Identification of alternative splicing exons of SfCHS1

It is known that the insect CHS1 gene exists as two alternative splicing variants. To identify the alternatively spliced exons of SfCHS1, one pair of gene-specific primers (ASV-F: 5′-TGACGATAACAGTGATACCA-3′ and ASV-R: 5′-GAATCGGCGTCATAGTCC-3′) were designed based on the full-length sequence of SfCHS1. cDNA was synthesized as described above. PCR was carried out via one cycle of pre-denaturation at 94 °C for 3 min, followed by 30 cycles of denaturation at 94 °C for 30 s, annealing at 51 °C for 30 s, and extension at 72 °C for 1 min, with a final extension at 72 °C for 10 min. A 648-bp amplified product was cloned into a pMD18-T vector and sequenced.

CDNA and amino acid sequence analysis

The sequenced fragments were assembled using SeqMan software to obtain the full-length sequence of SfCHS1 cDNA. The nucleotide sequence was edited using DNAMAN 7.0 (Lynnon Biosoft, CA, USA). Homology searches were performed using the NCBI BLAST program (https://blast.ncbi.nlm.nih.gov/Blast.cgi). The open reading frame (ORF) of SfCHS1 cDNA was identified using ORF finder (https://www.ncbi.nlm.nih.gov/orffinder/). The ProtParam tool at ExPASy (https://www.expasy.org/) was used to compute the molecular weight and theoretical isoelectric point (pI) of the deduced protein sequence 64 . N-glycosylation sites were analyzed using the NetNGlyc 1.0 Server (http://www.cbs.dtu.dk/services/NetNGlyc/), and the signal peptide was predicted using the SignalP 4.1 Server (http://www.cbs.dtu.dk/services/SignalP/). The TMHMM v.2.0 program (http://www.cbs.dtu.dk/services/TMHMM/) was used to analyze the transmembrane helices 65 . The putative coiled-coil regions were predicted using the Paircoil program 66 .

Phylogenetic analysis of insect chitin synthases

Phylogenetic trees were constructed using MEGA 6.06 based on the neighbor-joining (NJ) method 67 . Bootstrap analyses of 1000 replications were carried out. For Phylogenetic analysis, chitin synthases were included from Anasa tristis (At), Aphis glycines (Ag), Laodelphax striatellus (Ls), Nilaparvata lugens (Nl), Bombyx mori (Bm), Choristoneura fumiferana (Cf), Cnaphalocrocis medinalis (Cm), Ectropis obliqua (Eo), Helicoverpa armigera (Ha), Mamestra brassicae (Mb), Mamestra configurata (Mc), Manduca sexta (Ms), Ostrinia furnacalis (Of), Phthorimaea operculella (Po), Plutella xylostella (Px), Spodoptera exigua (Se), Spodoptera frugiperda (Sfr), Apis mellifera (Am), Pediculus humanus corporis (Ph), Anthonomus grandis (Agr), Tribolium castaneum (Tc), Anopheles gambiae (Aga), Anopheles quadrimaculatus (Aq), Bactrocera dorsalis (Bd), Culex quinquefasciatus (Cq), Drosophila melanogaster (Dm), Lucilia cuprina (Lc), Locusta migratoria manilensis (Lm). GenBank accession numbers are as follows: AtCHS (AFM38193), AgCHS1 (AFJ00066), LsCHS1a (AFC61179), LsCHS1b (AFC61178), NlCHS1a (AFC61181), NlCHS1b (AFC61180), BmCHS (AFB83705), CfCHS1 (ACD84882), CmCHS1 (AJG44538), CmCHS2 (AJG44539), EoCHS1a (ACA50098), EoCHS1b (ACD10533), HaCHS1 (AKZ08594), HaCHS2 (AKZ08595), MbCHS1 (ABX56676), McCHS2 (AJF93428), MsCHS1 (AAL38051), MsCHS2 (AAX20091), OfCHS1 (ACB13821), OfCHS2 (ABB97082), PoCHS1 (AOE23678), PoCHS2 (AIJ50381), PxCHS1 (BAF47974), SeCHS1 (AAZ03545), SeCHS2 (ABI96087),SfrCHS2 (AAS12599), AmCHS1 (XP_395677.4), AmCHS2 (XP_001121152.2), PhCHS2 (XP_002423604), AgrCHS1 (AHY28559), AgrCHS2 (AHY28560), TcCHS1a (AAQ55059), TcCHS1b (AAQ55060), TcCHS2 (AAQ55061), AgaCHS1a (XP_321336.5), AgaCHS1b (XP_321336.4), AgaCHS2 (XP_321951), AqCHS1 (ABD74441), BdCHS1a (AEN03040), BdCHS1b (AGB51153), BdCHS2 (AGC38392), CqCHS1 (XP_001866798), CqCHS2 (XP_001864594), DmCHS1 (NP_524233), DmCHS2 (NP_524209), LcCHS1 (AAG09712), LmCHS1a (ACY38588), LmCHS1b (ACY38589), and LmCHS2 (AFK08615).

Developmental- and tissue-specific expression of SfCHS1 and its two alternative splicing variants

S. furcifera at stages ranging from eggs to adults were sampled to determine the developmental stage expression profiles by quantitative real-time PCR (qPCR). Five different tissue samples from the integument, fat body, gut, ovary, and head were dissected from first-day fifth-instar nymphs and third-day adults to examine tissue-specific expression. Three biological replications were performed for each sample. Total RNA was isolated from the whole body of nymphs and adults at each stage or from the different tissues using an HP Total RNA Kit (with gDNA removal columns Omega bio-tek, Norcross, GA, USA). An AMV RT reagent Kit (Sangon Biotech) with an oligodT primer was used to synthesize first-strand cDNA. The most unique nucleotide regions of SfCHS1, SfCHS1a, and SfCHS1b were selected for expression analysis (the selected regions are shown in Figs 1 and 2), and the primers used for qPCR are listed in Table 2. The qPCR was performed in a CFX-96 real-time qPCR system (Bio-Rad, Hercules, CA, USA) with 20-μL reaction systems containing 10 μL FastStart Essential DNA Green Master (Roche Diagnostics, Shanghai, China), 1 μL cDNA (0.8 ng/μL), 1 μL (10 mM) of each primer, and 7 μL RNase-free water. Amplification conditions were as follows: an initial denaturation of 95 °C for 10 min and then 40 cycles of 95 °C for 30 s and 55 °C for 30 s. After the reaction, a melting-curve analysis from 65 to 95 °C was performed to confirm the specificity of the PCR. The data were normalized to the stable reference gene 18S ribosome RNA (GenBank accession no. HM017250) based on our previous evaluations 68 . The relative expression levels were calculated using the 2 −ΔΔCt method 69 .

Functional analysis of SfCHS1 and its two alternative splicing variants using RNAi

To further investigate the biological functions of SfCHS1 and its two alternative splicing variants, SfCHS1a and SfCHS1b, RNAi was carried out by injecting S. furcifera nymphs with sequence-specific dsRNA. The most unique nucleotide regions of SfCHS1, SfCHS1a and SfCHS1b were selected for dsRNA synthesis (the synthesized regions are shown in Figs 1 and 2), and the primers added a T7 RNA polymerase promoter (Table 2) were used to synthesize dsRNA. Templates for in vitro transcription reactions were synthesized by PCR from the plasmid DNA of SfCHS1, SfCHS1a, and SfCHS1b using primers. The PCR products of SfCHS1, SfCHS1a, and SfCHS1b were subcloned and sequenced to determine the specificity. The expected fragments were then purified using an EasyPure ® Quick Gel Extraction Kit (Transgen Biotech). The concentration of the purified products was determined using a Nanodrop 2000 spectrophotometer (Thermo Fisher Scientific) and these products were then used for in vitro transcription reactions.

dsRNAs were synthesized using a MEGAscript ® RNAi Kit (Ambion, Carlsbad, CA, USA) according to the user manual provided by the manufacturer. In vivo RNAi in S. furcifera nymphs was carried out as previously described 19,70 . First-day fifth-instar nymphs were anesthetized with carbon dioxide for approximately 30 s and subsequently used for microinjection. Each group included 50 nymphs and treatments were performed in triplicate. One hundred nanograms of dsRNA was injected into nymphs between the prothorax and mesothorax using a Nanoliter 2010 Injector (injection speed, 25 nL/s) (World Precision Instruments, FL, USA). Equivalent volumes of dsGFP were used for control injections. Injected nymphs were maintained on fresh rice under the conditions described above until eclosion, and thereafter phenotype and mortality were observed daily. Photographs were taken using a Keyence VH-Z20R stereoscopic microscope (Keyence, Osaka, Japan). Subsequent to injection, 10 nymphs were selected randomly from each replication for mRNA-level detection.

Statistical analysis

Statistical analysis of all data was performed using SPSS 13.0 software (IBM Inc., Chicago, IL, USA). Data values are represented as the mean ± SE of three replications. A one-way ANOVA and Duncan’s multiple range test (P < 0.05) were used to calculate the relative expression of each sample. For RNAi experiments, significant differences in mRNA levels between each of the dsRNA-injected groups and the dsGFP group were analyzed using t-tests.


Cordyceps-Anyone taking this?

i use mushroom science reishi. def the best reishi out right now. but i figure since the dr's best & jarrow are so much cheaper its worth trying them first. im most likely going with the dr's best. i'll report back with effects.

#32 maxwatt

i use mushroom science reishi. def the best reishi out right now. but i figure since the dr's best & jarrow are so much cheaper its worth trying them first. im most likely going with the dr's best. i'll report back with effects.

I believe Dr's best and Jarrow source from China I do not know which supplier there, or the consistency, quality or purity. Some are pharmaceutical quality, others not so much. Mushroom Science does not produce their own material they only have at most 4 employees according to Manta. Judging by their price, they are purchasing from a domestic producer. Stamets' is well respected in the mycological community, and he does grow his own mycelial cultures, and supplies others with cultures, supplies and grow-kits. You can buy the actual mushroom, with the dead caterpillar it grows from still attached, in most cities' Chinatowns. The ones in New York were going for 赀 an ounce last February.

Cordyceps extract is assumed to increase testosterone levels, though there are no published western studies in humans the effect has been demonstrated with leydig cells in vitro and with mice. Female runners on the Chinese Olympic team years ago were reportd to be using cordyceps, and after the coach was warned of positive tests for testosterone by doping control, they were purportedly allowed to withdaw without publicity to avoid an international incident. If cordyceps does not increase testosterone levels in females, it is one heck of a good cover story.

One effect of increased testosterone levels in women is a much-increased libido. The reported effects that Steve_86 posted above would also be consistent with increased testosterone levels. I look forward to feedback from those using this supplement.

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#33 ajnast4r

dr's best & jarrow always have good quality products, plus good reviews on iherb. i just bought the dr best from iherb. the fact that mushroom science only has 4 employees doesnt bother me at all. they sell wood grown, hot water extracted mushrooms standardized to very specific scientifically defined amounts of the actives. their reishi is very potent, so potent (sedative) that i cant even take it during the day.

im going for exactly the effects steve listed

#34 ajnast4r

when i run out of dr's best im going to try aloha medicinals. http://www.alohamedicinals.com/

they have a pretty convincing schpiel about their cordyceps being superior & the lab work to back it up. its also only slightly more expensive than dr's best, and way cheaper than mushroom science.

Edited by ajnast4r, 06 November 2010 - 07:23 PM.

#35 pycnogenol

when i run out of dr's best im going to try aloha medicinals. http://www.alohamedicinals.com/

they have a pretty convincing schpiel about their cordyceps being superior & the lab work to back it up. its also only slightly more expensive than dr's best, and way cheaper than mushroom science.

Yeah these Aloha cats give awesome spiel so I might try them out too.

#36 maxwatt

dr's best & jarrow always have good quality products, plus good reviews on iherb. i just bought the dr best from iherb. the fact that mushroom science only has 4 employees doesnt bother me at all. they sell wood grown, hot water extracted mushrooms standardized to very specific scientifically defined amounts of the actives. their reishi is very potent, so potent (sedative) that i cant even take it during the day.

im going for exactly the effects steve listed

Sigh. They say no good deed goes unpunished.

How do you know Dr's Best has good quality products? Consumer Labs caught them out at least once. Jarrow? I've gotten bottles with broken capsules, partly filled capsules, and what looked like floor sweepings in the capsules. True, anyone can have a bad batch in a largish operation but reputations can be overblown and out of date. Both companies do skip-lot testing, as the FDA allows. It's like people who are famous for being famous. They're good because everybody says they're good. Even so, I'd take them over most others in the business but for mushroom products I'd go to the source, or as close as possible.

My point on Mushroom Science is that they are too small to produce themselves. They probably are conscientious and use high quality sources, but they are not primary producers. They contract out manufacture to a GMC facility, which may source the material for them. It can and probably still is of good quality.

Among professional mycologists (and I know several personally) Stamets' reputation stands out. I think most if not all producers in this country get their cultures from him.

#37 ajnast4r

How do you know Dr's Best has good quality products? Consumer Labs caught them out at least once. Jarrow? I've gotten bottles with broken capsules, partly filled capsules, and what looked like floor sweepings in the capsules. True, anyone can have a bad batch in a largish operation but reputations can be overblown and out of date. Both companies do skip-lot testing, as the FDA allows. It's like people who are famous for being famous. They're good because everybody says they're good. Even so, I'd take them over most others in the business but for mushroom products I'd go to the source, or as close as possible.

My point on Mushroom Science is that they are too small to produce themselves. They probably are conscientious and use high quality sources, but they are not primary producers. They contract out manufacture to a GMC facility, which may source the material for them. It can and probably still is of good quality.

Among professional mycologists (and I know several personally) Stamets' reputation stands out. I think most if not all producers in this country get their cultures from him.

dr's best & jarrow are both manufactured in facilities that are as good as you can get. everyone says they are good because they ARE. the best in fact. i would invite you to contact them and ask them about the quality of their manufacturing. they are both HACCP, ISO 9001, cGMP etc etc etc.

i dont think that being the primary producer is really indicative of quality. if it was, we would have to x out 99% of the supplements sold in the US. I'm not arguing that stammets products arent good.. but they are insanely overpriced. i would take 'conscientious and high quality sources' with reasonable prices over self-produced & overpriced.

40c per pill & mushroom science is

22c per pill
stammets cordyeps is

40c per pills & dr best is

w/ the stammets stuff you really are just paying for his name on the label.

#38 Logan

How do you know Dr's Best has good quality products? Consumer Labs caught them out at least once. Jarrow? I've gotten bottles with broken capsules, partly filled capsules, and what looked like floor sweepings in the capsules. True, anyone can have a bad batch in a largish operation but reputations can be overblown and out of date. Both companies do skip-lot testing, as the FDA allows. It's like people who are famous for being famous. They're good because everybody says they're good. Even so, I'd take them over most others in the business but for mushroom products I'd go to the source, or as close as possible.

My point on Mushroom Science is that they are too small to produce themselves. They probably are conscientious and use high quality sources, but they are not primary producers. They contract out manufacture to a GMC facility, which may source the material for them. It can and probably still is of good quality.

Among professional mycologists (and I know several personally) Stamets' reputation stands out. I think most if not all producers in this country get their cultures from him.

dr's best & jarrow are both manufactured in facilities that are as good as you can get. everyone says they are good because they ARE. the best in fact. i would invite you to contact them and ask them about the quality of their manufacturing. they are both HACCP, ISO 9001, cGMP etc etc etc.

i dont think that being the primary producer is really indicative of quality. if it was, we would have to x out 99% of the supplements sold in the US. I'm not arguing that stammets products arent good.. but they are insanely overpriced. i would take 'conscientious and high quality sources' with reasonable prices over self-produced & overpriced.

40c per pill & mushroom science is

22c per pill
stammets cordyeps is

40c per pills & dr best is

w/ the stammets stuff you really are just paying for his name on the label.

I believe Fungi Perfect are freezed dried, that may make them superior to other brands. You definitely pay for the name when you buy Stamets' products, but the guy does know his mushrooms, and I think his mushroom products are better than most.

#39 ajnast4r

stamets at TED:

something mushroom science touches on, and something ive been wondering about, is the bioavailability of the various substances in mushrooms. re: extracts vs unextracted powder. ALL the research I was able to find, and all the references to traditional/TCM consumption were with extracts (water and/or alcohol). this makes me question the bioavailability of unextracted power in a pill.

Every form of extraction, including precipitation with alcohol, requires a heated liquid solution to first release the polysaccharides, the primary active compounds, from the chitinous cell walls of the mushroom and mushroom mycelium.(8)

This is true for Reishi(9,10) Coriolus versicolor(11,12) Maitake(13) Shiitake(14,15) and Cordyceps.(16) All of the well-known isolates are also extracted in a heated aqueous solution, including Maitake Fraction from Maitake, PSK/VPS and PSP from Coriolus versicolor, and Lentinan and LEM from Shiitake.

According to the American Herbal Pharmacopoeia mycelium bio-mass products are inferior because of a "lack of bio-availability". This publication also states that concentrates derived through proper extraction contain active compounds "magnitudes higher than what is available in crude mycelium biomass preparations".(17)

#40 pycnogenol

How do you know Dr's Best has good quality products? Consumer Labs caught them out at least once. Jarrow? I've gotten bottles with broken capsules, partly filled
capsules, and what looked like floor sweepings in the capsules. True, anyone can have a bad batch in a largish operation but reputations can be overblown and out of date.

Both companies do skip-lot testing, as the FDA allows.

Edited by pycnogenol, 07 November 2010 - 02:43 PM.

#41 Animal

How do you know Dr's Best has good quality products? Consumer Labs caught them out at least once. Jarrow? I've gotten bottles with broken capsules, partly filled capsules, and what looked like floor sweepings in the capsules. True, anyone can have a bad batch in a largish operation but reputations can be overblown and out of date. Both companies do skip-lot testing, as the FDA allows. It's like people who are famous for being famous. They're good because everybody says they're good. Even so, I'd take them over most others in the business but for mushroom products I'd go to the source, or as close as possible.

My point on Mushroom Science is that they are too small to produce themselves. They probably are conscientious and use high quality sources, but they are not primary producers. They contract out manufacture to a GMC facility, which may source the material for them. It can and probably still is of good quality.

Among professional mycologists (and I know several personally) Stamets' reputation stands out. I think most if not all producers in this country get their cultures from him.

dr's best & jarrow are both manufactured in facilities that are as good as you can get. everyone says they are good because they ARE. the best in fact. i would invite you to contact them and ask them about the quality of their manufacturing. they are both HACCP, ISO 9001, cGMP etc etc etc.

i dont think that being the primary producer is really indicative of quality. if it was, we would have to x out 99% of the supplements sold in the US. I'm not arguing that stammets products arent good.. but they are insanely overpriced. i would take 'conscientious and high quality sources' with reasonable prices over self-produced & overpriced.

40c per pill & mushroom science is

22c per pill
stammets cordyeps is

40c per pills & dr best is

w/ the stammets stuff you really are just paying for his name on the label.

Yes that's all well and good, but do you personally know several professional mycologists? I think not, therefore.

#42 ajnast4r

i was unable to fine -any- positive research on unextracted mushroom mycelium. ive also exchanged a few emails with the guy over at mushroom science and this all has me pretty much convinced that extracts are the only way to go. that being said i am still going to finish out my bottle of dr's best cordyceps mycelium and then compare it to the mushroom science extract. ill post back later.

to reiterate what i gathered from the emails:

only non-linear polysaccharides stimulate the immune system, and while up to 40-50% of the weight of raw mycellium can be polysaccharide, this amount is contributed to by the grain it is grown on & only 1-2% are the immune stimulating, non-linear portion. the non-linear polysaccharides are bound up in the chitinnous cell walls are not bioavailable unless they are heat treated. which breaks up the chitin, releasing the betaglucan.

Attached Files

Edited by ajnast4r, 09 November 2010 - 01:21 AM.

#43 Logan

dr's best & jarrow always have good quality products, plus good reviews on iherb. i just bought the dr best from iherb. the fact that mushroom science only has 4 employees doesnt bother me at all. they sell wood grown, hot water extracted mushrooms standardized to very specific scientifically defined amounts of the actives. their reishi is very potent, so potent (sedative) that i cant even take it during the day.

im going for exactly the effects steve listed

Sigh. They say no good deed goes unpunished.

How do you know Dr's Best has good quality products? Consumer Labs caught them out at least once. Jarrow? I've gotten bottles with broken capsules, partly filled capsules, and what looked like floor sweepings in the capsules. True, anyone can have a bad batch in a largish operation but reputations can be overblown and out of date. Both companies do skip-lot testing, as the FDA allows. It's like people who are famous for being famous. They're good because everybody says they're good. Even so, I'd take them over most others in the business but for mushroom products I'd go to the source, or as close as possible.

I think Jarrow, being based in California, has to adhere to very strict guidelines and testing. Proposition 65?

#44 ajnast4r

I think Jarrow, being based in California, has to adhere to very strict guidelines and testing. Proposition 65?

#45 ajnast4r

#46 Steve_86

also looking at NutraceuticsRx CordyPure which is using this extract. It costs a FRACTION of what the mushroom science extract cost. i havent determined which is the superior extract. will report back when i do.

What do you think of the product here: http://www.alohamedi. /cordyceps.html

I emailed them and they sell 1kg for ๳USD

#47 ajnast4r

also looking at NutraceuticsRx CordyPure which is using this extract. It costs a FRACTION of what the mushroom science extract cost. i havent determined which is the superior extract. will report back when i do.

What do you think of the product here: http://www.alohamedi. /cordyceps.html

I emailed them and they sell 1kg for ๳USD

that is just raw, unprocessed mycellium and should have negligible effects. see what i wrote it post 42 of this thread

#48 Steve_86

also looking at NutraceuticsRx CordyPure which is using this extract. It costs a FRACTION of what the mushroom science extract cost. i havent determined which is the superior extract. will report back when i do.

I emailed them and they sell 1kg for ๳USD

that is just raw, unprocessed mycellium and should have negligible effects. see what i wrote it post 42 of this thread

While extracts are much better in terms of potency, raw unprocessed myecellium is much cheaper. Currently I take 15-20grams/day of Smart-Powders cordyceps and it seems to be working fairly well. Do you believe an extract would provide significant benefits over such doses of unprocessed myecellium?

#49 ajnast4r

While extracts are much better in terms of potency, raw unprocessed myecellium is much cheaper. Currently I take 15-20grams/day of Smart-Powders cordyceps and it seems to be working fairly well. Do you believe an extract would provide significant benefits over such doses of unprocessed myecellium?

it doesnt list any info, but the 7% part leads me to believe its an extract not raw mycellium. if it is indeed an extract you do not want to be taking 15-20g per day. you are also going to want to check into the heavy metal content, as cordyceps is prone to lead contamination from what i've read.

if it IS raw mycellium, because most of the goodies are bound up in the cell walls. and you dont have the capability to digest the cell walls. you are most likely only getting whatever trace amounts have been liberated by pulverization. this is a good article on mushroom bioavailability by a reliable manufacturer.

you can get a good quality bulk extract like this for 60$ and only have to take .75-1.5 grams per day to realize the good effects. its a 15:1 extract so 1g of this extract would be equivalent to 15g raw cordyceps (by weight, ie: if the substances were actually bioavailable) more money out the door, but MUCH more money saved in the long run.

Edited by ajnast4r, 13 November 2010 - 07:06 PM.

#50 chrono

they sell wood grown, hot water extracted mushrooms standardized to very specific scientifically defined amounts of the actives

I only found one mention of "standardized" on their website. I think most of them are just regular extracts. Could be wrong?

w/ the stammets stuff you really are just paying for his name on the label.

May be true for some of it. As someone else mentioned, the mycelium is freeze dried, which may or may not matter. Also, their lion's mane extract is the only one I would use or recommend they extract both the fruit body and mycelium, using water and alcohol separately, then combine them. This suggest to me that, in general, they probably know what they're doing more than most other outfits.

ALL the research I was able to find, and all the references to traditional/TCM consumption were with extracts (water and/or alcohol). this makes me question the bioavailability of unextracted power in a pill.

Amanitas and psilocybin mushrooms are definitely eaten raw, and the study using LM to treat dementia used whole mushrooms in soup. And I'm pretty sure most traditional mushrooms were used whole (at least sometimes), though I don't have any traditional references for mushrooms on hand to demonstrate this.

the non-linear polysaccharides are bound up in the chitinnous cell walls are not bioavailable unless they are heat treated. which breaks up the chitin, releasing the betaglucan.

Human gastric juice contains chitinase that can degrade chitin.
Paoletti MG, Norberto L, Damini R, Musumeci S.
Department of Biology, Laboratory Agroecology and Ethnobiology, University of Padova, Padova, Italy.

Chitin digestion by humans has generally been questioned or denied. Only recently chitinases have been found in several human tissues and their role has been associated with defense against parasite infections and to some allergic conditions. In this pilot study we tested the gastric juices of 25 Italian subjects on the artificial substrates 4-methylumbelliferyl-beta-D-N,N',diacetylchitobiose or/and fluorescein isothiocyanate (FITC) chitin to demonstrate the presence of a chitinase activity. Since this chitinase activity was demonstrated at acidic pH, it is currently referred to acidic mammalian chitinase (AMCase). AMCase activity was present in gastric juices of twenty of 25 Italian patients in a range of activity from 0.21 to 36.27 nmol/ml/h and from 8,881 to 1,254,782 fluorescence emission (CPS), according to the used methods. In the remaining five of 25 gastric juices, AMCase activity was almost absent in both assay methods. An allosamidine inhibition test and the measurement at different pH values confirmed that this activity was characteristic of AMCase. The absence of activity in 20% of the gastric juices may be a consequence of virtual absence of chitinous food in the Western diet.

PMID: 17587796 [PubMed - indexed for MEDLINE]

#51 ajnast4r

I think most of them are just regular extracts. Could be wrong?

i'm not sure why their website doesnt mention it but you can view more info on iherb: http://www.iherb.com. cience#p=1&sr=0

the reishi i use is 15% betaglucan, 6% triterpenoids

May be true for some of it. As someone else mentioned, the mycelium is freeze dried, which may or may not matter. Also, their lion's mane extract is the only one I would use or recommend they extract both the fruit body and mycelium, using water and alcohol separately, then combine them. This suggest to me that, in general, they probably know what they're doing more than most other outfits.

are the fungi perfecti line capsules extracted? it doesnt mention anything about it on the website.

Amanitas and psilocybin mushrooms are definitely eaten raw, and the study using LM to treat dementia used whole mushrooms in soup. And I'm pretty sure most traditional mushrooms were used whole (at least sometimes), though I don't have any traditional references for mushrooms on hand to demonstrate this.

in TCM mushrooms are made into soup or tea. which is essentially hot water extraction. i couldnt find any studies or tcm referenced to eating mushrooms raw. a good portion of the medicinal mushrooms arent edible raw. reshi, cordyceps etc are solid & woody.

Human gastric juice contains chitinase that can degrade chitin.
Paoletti MG, Norberto L, Damini R, Musumeci S.
Department of Biology, Laboratory Agroecology and Ethnobiology, University of Padova, Padova, Italy.

Chitin digestion by humans has generally been questioned or denied. Only recently chitinases have been found in several human tissues and their role has been associated with defense against parasite infections and to some allergic conditions. In this pilot study we tested the gastric juices of 25 Italian subjects on the artificial substrates 4-methylumbelliferyl-beta-D-N,N',diacetylchitobiose or/and fluorescein isothiocyanate (FITC) chitin to demonstrate the presence of a chitinase activity. Since this chitinase activity was demonstrated at acidic pH, it is currently referred to acidic mammalian chitinase (AMCase). AMCase activity was present in gastric juices of twenty of 25 Italian patients in a range of activity from 0.21 to 36.27 nmol/ml/h and from 8,881 to 1,254,782 fluorescence emission (CPS), according to the used methods. In the remaining five of 25 gastric juices, AMCase activity was almost absent in both assay methods. An allosamidine inhibition test and the measurement at different pH values confirmed that this activity was characteristic of AMCase. The absence of activity in 20% of the gastric juices may be a consequence of virtual absence of chitinous food in the Western diet.

PMID: 17587796 [PubMed - indexed for MEDLINE][/indent]

interesting study but, to me, that just proves the need for an extract.. being that 20% of the population in that study lacked the ability to digest chitin. also who knows how much chitin anyone could actually digest & if it would be enough to make the mushrooms medicinally viable.


Abstract

The article summarizes the roles of polysaccharides in the biology of fungi and their relationship in the development of new technologies. The comparative approach between the evolution of fungi and the chemistry of glycobiology elucidated relevant aspects about the role of polysaccharides in fungi. Also, based on the knowledge of fungal glycobiology, it was possible to address the development of new technologies, such as the production of new anti-tumor drugs, vaccines, biomaterials, and applications in the field of robotics. We conclude that polysaccharides activate pathways of apoptosis, secretion of pro-inflammatory substances, and macrophage, inducing anticancer activity. Also, the activation of the immune system, which opens the way for the production of vaccines. The development of biomaterials and parts for robotics is a promising and little-explored field. Finally, the article is multidisciplinary, with a different and integrated approach to the role of nature in the sustainable development of new technologies.


Meet the enemy of killer fungus that turns ants into zombies

When microbes cause ants to become zombies. Credit: Tommy Leung

One of most famous fungi in the world is the "zombie ant fungus". It takes over the mind of an ant, causing it to climb up a branch and cling to the underside of a leaf before mummification. Once locked in place, the mushroom-like fruiting body of the cordyceps sprouts from the ant and eventually releases its spores.

This ant-killing fungus goes by the scientific name Ophiocordyceps unilateralis and its modus operandi has made it something of a celebrity – inspiring an episode of The X files, the video game The Last of Us and even a Pokémon character.

This fame might make it seem there is just one fungus that can create such a nightmare. But in fact there are many species of them, and zombifying ants is not their only speciality.

In just the Ophiocordyceps genus there are more than 100 species. Many insects can fall under their spell – beetles, caterpillars, cicada and dragonflies are all fair game. There is fossil evidence indicating that this has been going on for more than 40m years. But while these fungi are master body-snatchers, they don't always get everything to themselves. Sometimes two of these fungi can infect the same ant.

Last month scientists in Japan studying these fungi started noticing that some zombified ants were afflicted with two distinct forms of cordyceps fungi. Both fungi were found sprouting from dead ants that had their mandibles clamped tightly around a branch in the typical zombie-ant pose. One fungus species, O. pulvinata, produces a bulbous fruiting body that juts from the back of the ant's head. The other, O. sessilis, covers the ant's body in spiny fruiting bodies.

There is nothing peculiar about that as cordyceps come in many different shapes, but what stood out was that they also noticed O. sessilis is only ever found in ants that are also infected with O. pulvinata. Rather than a case of a pair of fungi cozily sharing the same host, the scientists suggested that O. sessilis is actually a parasite of O. pulvinata itself.

This is an example of hyperparasitism – whereby a parasite itself becomes infected by a parasite. Jonathan Swift was on to something in his oft-misquoted poem:

"So, naturalists observe, a flea
Hath smaller fleas that on him prey
And these have smaller fleas to bite 'em
And so proceed ad infinitum."

The behaviour is observed in other parasites. For instance, parasitic barnacles that castrate crabs can in turn be infected with their own castrating parasite and salmon lice are sometimes infected with microsporidian parasites.

Switching hosts from an insect to another fungi (or vice versa) seems to be fairly common among cordyceps fungi. And there may be an evolutionary reason for this adaptation.

The microscopic spores of a fungus get inside the insect by puncturing their tough exoskeleton. This is done by secreting enzymes that dissolve chitin, which happens to be the same material that makes up the cell wall of fungi. So any fungus able to chew through an insect's exoskeleton is already equipped to attack other fungi.

But apart from enemies within the cordyceps, the zombie ant fungus also faces threats from other types of hyperparasitic fungi. After the cordyceps has moved the zombified ant into the ideal position, the spore-producing fruiting body punches through the host's exoskeletal shell and takes at least two weeks to reach maturity. During that time, it is vulnerable to spores of other types of fungi that specialise in taking over cordyceps, covering it in a dense white mould and rendering it sterile.

Usually the enemy of an enemy is a friend, but that is of no consequence for a zombified ant. To these fungi the ant is but a stage upon which they play out their lives and conflicts, as they have been doing for millions of years.

This story is published courtesy of The Conversation (under Creative Commons-Attribution/No derivatives).