''Claviceps purpurea'' is an ergot

fungus A fungus ( : fungi or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, separately from t ...

that grows on the

ear An ear is the organ that enables hearing and, in mammals, body balance using the vestibular system. In mammals, the ear is usually described as having three parts—the outer ear, the middle ear and the inner ear. The outer ear consists of ...

s of rye and related cereal and forage plants. Consumption of grains or seeds contaminated with the survival structure of this fungus, the ergot sclerotium, can cause ergotism in humans and other mammals. ''C. purpurea'' most commonly affects outcrossing species such as rye (its most common host), as well as

triticale Triticale (; × ''Triticosecale'') is a hybrid of wheat (''Triticum'') and rye (''Secale'') first bred in laboratories during the late 19th century in Scotland and Germany. Commercially available triticale is almost always a second-generation ...

wheat Wheat is a grass widely cultivated for its seed, a cereal grain that is a worldwide staple food. The many species of wheat together make up the genus ''Triticum'' ; the most widely grown is common wheat (''T. aestivum''). The archaeologi ...

and

barley Barley (''Hordeum vulgare''), a member of the grass family, is a major cereal grain grown in temperate climates globally. It was one of the first cultivated grains, particularly in Eurasia as early as 10,000 years ago. Globally 70% of barley p ...

. It affects

oat The oat (''Avena sativa''), sometimes called the common oat, is a species of cereal grain grown for its seed, which is known by the same name (usually in the plural, unlike other cereals and pseudocereals). While oats are suitable for human con ...

s only rarely.

Life cycle

Claviceps purpurea - Köhler–s Medizinal-Pflanzen-185-en

An ''ergot kernel'' called ''Sclerotium clavus'' develops when a floret of flowering grass or cereal is infected by an ascospore of ''C. purpurea''. The infection process mimics a pollen grain growing into an ovary during

fertilization Fertilisation or fertilization (see spelling differences), also known as generative fertilisation, syngamy and impregnation, is the fusion of gametes to give rise to a new individual organism or offspring and initiate its development. Proce ...

. Because infection requires access of the fungal spore to the stigma, plants infected by ''C. purpurea'' are mainly outcrossing species with open flowers, such as rye ('' Secale cereale'') and

Alopecurus ''Alopecurus'', or foxtail grass, is a common and widespread genus of plants in the grass family. It is common across temperate and subtropical parts of Eurasia, northern Africa, and the Americas, as well as naturalized in Australia and on vari ...

. The proliferating fungal mycelium then destroys the plant ovary and connects with the vascular bundle originally intended for feeding the developing

seed A seed is an embryonic plant enclosed in a protective outer covering, along with a food reserve. The formation of the seed is a part of the process of reproduction in seed plants, the spermatophytes, including the gymnosperm and angiospe ...

. The first stage of ergot infection manifests itself as a white soft tissue (known as ''Sphacelia segetum'') producing sugary honeydew, which often drops out of the infected grass florets. This honeydew contains millions of asexual spores ( conidia) which are dispersed to other florets by

insect Insects (from Latin ') are pancrustacean hexapod invertebrates of the class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body ( head, thorax and abdomen), three ...

s or rain. Later, the ''Sphacelia segetum'' convert into a hard dry ''Sclerotium clavus'' inside the husk of the floret. At this stage,

alkaloid Alkaloids are a class of basic, naturally occurring organic compounds that contain at least one nitrogen atom. This group also includes some related compounds with neutral and even weakly acidic properties. Some synthetic compounds of similar ...

s and

lipid Lipids are a broad group of naturally-occurring molecules which includes fats, waxes, sterols, fat-soluble vitamins (such as vitamins A, D, E and K), monoglycerides, diglycerides, phospholipids, and others. The functions of lipids includ ...

s (e.g.

ricinoleic acid Ricinoleic acid, formally called 12-hydroxy-9-''cis''-octadecenoic acid is a fatty acid. It is an unsaturated omega-9 fatty acid and a hydroxy acid. It is a major component of the seed oil obtained from mature castor plant (''Ricinus communis' ...

) accumulate in the Sclerotium. When a mature ''Sclerotium'' drops to the ground, the fungus remains dormant until proper conditions trigger its fruiting phase (onset of spring, rain period, need of fresh temperatures during winter, etc.). It germinates, forming one or several

fruiting bodies The sporocarp (also known as fruiting body, fruit body or fruitbody) of fungi is a multicellular structure on which spore-producing structures, such as basidia or asci, are borne. The fruitbody is part of the sexual phase of a fungal life cyc ...

with head and stipe, variously colored (resembling a tiny

mushroom A mushroom or toadstool is the fleshy, spore-bearing fruiting body of a fungus, typically produced above ground, on soil, or on its food source. ''Toadstool'' generally denotes one poisonous to humans. The standard for the name "mushroom" is ...

). In the head, threadlike

sexual Sex is the biological distinction of an organism between male and female. Sex or SEX may also refer to: Biology and behaviour *Animal sexual behaviour **Copulation (zoology) **Human sexual activity **Non-penetrative sex, or sexual outercourse ** ...

spores (ascospores) are formed in

perithecia An ascocarp, or ascoma (), is the fruiting body ( sporocarp) of an ascomycete phylum fungus. It consists of very tightly interwoven hyphae and millions of embedded asci, each of which typically contains four to eight ascospores. Ascocarps are mos ...

, which are ejected simultaneously, when suitable grass hosts are flowering. Ergot infection causes a reduction in the yield and quality of grain and hay produced, and if infected grain or hay is fed to livestock it may cause a disease called ergotism. '' Polistes dorsalis'', a species of social wasps, have been recorded as a vector of the spread of this particular fungus. During their foraging behavior, particles of the fungal conidia get bound to parts of this wasp's body. As ''P. dorsalis'' travels from source to source, it leaves the fungal infection behind. Insects, including flies and moths, have also been shown to carry conidia of ''Claviceps'' species, but if insects play a role in spreading the fungus from infected to healthy plants is unknown.

Intraspecific variations

Early scientists have observed ''Claviceps purpurea'' on other Poaceae as ''

Secale cereale Rye (''Secale cereale'') is a grass grown extensively as a grain, a cover crop and a forage crop. It is a member of the wheat tribe (Triticeae) and is closely related to both wheat (''Triticum'') and barley (genus ''Hordeum''). Rye grain is ...

''. 1855, Grandclement described ergot on ''

Triticum aestivum Common wheat (''Triticum aestivum''), also known as bread wheat, is a cultivated wheat species. About 95% of wheat produced worldwide is common wheat; it is the most widely grown of all crops and the cereal with the highest monetary yield. Ta ...

''. During more than a century scientists aimed to describe specialized species or specialized varieties inside the species ''Claviceps purpurea''. * ''Claviceps microcephala'' Tul. (1853) * ''Claviceps wilsonii'' Cooke (1884) Later scientists tried to determine host varieties as * ''Claviceps purpurea'' var. ''agropyri'' * ''Claviceps purpurea'' var. ''purpurea'' * ''Claviceps purpurea'' var. ''spartinae'' * ''Claviceps purpurea'' var. ''wilsonii''. Molecular biology has not confirmed this hypothesis but has distinguished three groups differing in their ecological specificity. * G1—land grasses of open meadows and fields; * G2—grasses from moist, forest, and mountain habitats; * G3 (''C. purpurea'' var. ''spartinae'')—salt marsh grasses (Spartina, Distichlis). Morphological criteria to distinguish different groups: The shape and the size of sclerotia are not good indicators because they strongly depend on the size and shape of the host floret. The size of conidia can be an indication but it is weak and it is necessary to pay attention to that, due to osmotic pressure, it varies significantly if the spores are observed in honeydew or in water. The sclerotial density can be used as the groups G2 and G3 float in water. The compound of alkaloids is also used to differentiate the strains.

Host range

Pooideae

Agrostis canina ''Agrostis canina'', the velvety bentgrass, brown bent or velvet bent, is a species of grass in the family Poaceae. Description ''Agrostis canina'' is a perennial plant, with stolons but no rhizomes, and culms which grow to a height of up t ...

'', '' Alopecurus myosuroides'' (G2), '' Alopecurus arundinaceus'' (G2), ''

Alopecurus pratensis ''Alopecurus pratensis'', known as the meadow foxtail or the field meadow foxtail, is a perennial grass belonging to the grass family (Poaceae). It is native to Europe and Asia. This common plant is found on grasslands, especially on neutral so ...

'', ''

Bromus arvensis ''Bromus arvensis'', the field brome, is a brome grass native to Europe and Asia. The specific epithet ''arvensis'' is Latin, meaning "of cultivated land". Description ''Bromus arvensis'' is an annual or biennial grass with erect culms growin ...

'', ''

Bromus commutatus ''Bromus commutatus'', the meadow brome, is an annual or biennial species of plant in the grass family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other ...

'', ''

Bromus hordeaceus ''Bromus hordeaceus'', the soft brome, is an annual or biennial species of grass in the true grass family ( Poaceae). It is also known in North America as bull grass, soft cheat, and soft chess. It is the most common species of ''Bromus'' in Bri ...

'' (G2), ''

Bromus inermis ''Bromus inermis'' is a species of the true grass family ( Poaceae). This rhizomatous grass is native to Europe Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the ...

'', '' Bromus marginatus'', ''

Elymus tsukushiense Elymus may refer to: * ''Elymus'' (plant), a genus of grasses * Elymus (mythology), the mythical ancestor of the Elymians * A man killed by Gorge (mythology) In Greek mythology, Gorge( grc, Γόργη, comes from the adjective ''gorgos,'' "terri ...

'', ''

Festuca arundinacea ''Festuca arundinacea'' ( syn., ''Schedonorus arundinaceus'' and ''Lolium arundinaceum'') is a species of grass commonly known as tall fescue. It is a cool-season perennial C3 species of bunchgrass native to Europe. It is an important forage g ...

'', ''

Elymus repens ''Elymus repens'', commonly known as couch grass, is a very common perennial species of grass native to most of Europe, Asia, the Arctic biome, and northwest Africa. It has been brought into other mild northern climates for forage or erosion cont ...

'' (G1), ''

Nardus stricta ''Nardus'' is a genus of plants belonging to the grass family, containing the single species ''Nardus stricta'', known as matgrass. It is placed in its own tribe Nardeae within the subfamily Pooideae. The name derives from ancient Greek ' () from ...

'', ''

Poa annua ''Poa annua'', or annual meadow grass (known in America more commonly as annual bluegrass or simply poa), is a widespread low-growing turfgrass in temperate climates. Notwithstanding the reference to annual plant in its name, perennial bio-types ...

'' (G2), ''

Phleum pratense Timothy (''Phleum pratense'') is an abundant perennial grass native to most of Europe except for the Mediterranean region. It is also known as timothy-grass, meadow cat's-tail or common cat's tail. It is a member of the genus ''Phleum'', consis ...

'', ''

Phalaris arundinacea ''Phalaris arundinacea'', or reed canary grass, is a tall, Perennial plant, perennial bunchgrass that commonly forms extensive single-species stands along the margins of lakes and streams and in wet open areas, with a wide distribution in Europe ...

'' (G2), ''

Poa pratensis ''Poa pratensis'', commonly known as Kentucky bluegrass (or blue grass), smooth meadow-grass, or common meadow-grass, is a perennial species of grass native to practically all of Europe, North Asia and the mountains of Algeria and Morocco. Altho ...

'' (G1), ''

Stipa ''Stipa'' is a genus of around 300 large perennial hermaphroditic grasses collectively known as feather grass, needle grass, and spear grass. They are placed in the subfamily Pooideae and the tribe Stipeae, which also contains many species for ...

''.

Arundinoideae

Danthonia ''Danthonia'' is a genus of Eurasian, North African, and American plants in the grass family. Members of this genus are sometimes referred to as oatgrass, but that common name is not restricted to this genus. Other common names include heathgra ...

'', ''

Molinia caerulea ''Molinia caerulea'', known by the common name purple moor-grass, is a species of grass that is native to Europe, west Asia, and north Africa. It grows in locations from the lowlands up to in the Alps. Like most grasses, it grows best in acid s ...

''.

Chloridoideae

Spartina ''Spartina'' is a taxon of plants in the grass family, frequently found in coastal salt marshes. Its species are commonly known as cordgrass or cord-grass, and are native to the coasts of the Atlantic Ocean in western and southern Europe, nort ...

'', ''

Distichlis ''Distichlis'' is a genus of American and Australian plants in the grass family.Bell, H. L. & J. T. Columbus. 2008. Proposal for an expanded ''Distichlis'' (Poaceae, Chloridoideae): Support from molecular, morphological, and anatomical charact ...

'' (G3)

Panicoideae

Setaria ''Setaria'' is a widespread genus of plants in the grass family. The name is derived from the Latin word ''seta'', meaning "bristle" or "hair", which refers to the bristly spikelets. The genus includes over 100 species distributed in many t ...

Epidemiology

''Claviceps purpurea'' has been known to humankind for a long time, and its appearance has been linked to extremely cold winters that were followed by rainy springs. The sclerotial stage of ''C. purpurea'' conspicuous on the heads of ryes and other such grains is known as ergot. Sclerotia germinate in spring after a period of low temperature. A temperature of 0-5 °C for at least 25 days is required. Water before the cold period is also necessary. Favorable temperatures for stroma production are in the range of 10-25 °C. Favorable temperatures for mycelial growth are in the range of 20-30 °C with an optimum at 25 °C. Sunlight has a chromogenic effect on the mycelium with intense coloration.

Effects

The disease cycle of the ergot fungus was first described in 1853, but the connection with ergot and epidemics among people and animals was reported already in a scientific text in 1676. The ergot sclerotium contains high concentrations (up to 2% of dry mass) of the

ergotamine Ergotamine, sold under the brand names Cafergot (with caffeine) and Ergomar among others, is an ergopeptine and part of the ergot family of alkaloids; it is structurally and biochemically closely related to ergoline. It possesses structural sim ...

, a complex molecule consisting of a tripeptide-derived cyclol-lactam ring connected via

amide In organic chemistry, an amide, also known as an organic amide or a carboxamide, is a compound with the general formula , where R, R', and R″ represent organic groups or hydrogen atoms. The amide group is called a peptide bond when it i ...

linkage to a

lysergic acid Lysergic acid, also known as -lysergic acid and (+)-lysergic acid, is a precursor for a wide range of ergoline alkaloids that are produced by the ergot fungus and found in the seeds of '' Turbina corymbosa'' (ololiuhqui), '' Argyreia nervosa'' ...

(ergoline) moiety, and other alkaloids of the

ergoline Ergoline is a chemical compound whose structural skeleton is contained in a variety of alkaloids, referred to as ergoline derivatives or ergoline alkaloids. Ergoline alkaloids, one being ergine, were initially characterized in ergot. Some of thes ...

group that are

biosynthesized Biosynthesis is a multi-step, enzyme- catalyzed process where substrates are converted into more complex products in living organisms. In biosynthesis, simple compounds are modified, converted into other compounds, or joined to form macromolecules ...

by the fungus. Ergot alkaloids have a wide range of biological activities including effects on circulation and

neurotransmission Neurotransmission (Latin: ''transmissio'' "passage, crossing" from ''transmittere'' "send, let through") is the process by which signaling molecules called neurotransmitters are released by the axon terminal of a neuron (the presynaptic neuron), ...

. Ergotism is the name for sometimes severe pathological syndromes affecting humans or animals that have ingested ergot alkaloid-containing plant material, such as ergot-contaminated grains. Monks of the order of St.

Anthony the Great Anthony the Great ( grc-gre, Ἀντώνιος ''Antṓnios''; ar, القديس أنطونيوس الكبير; la, Antonius; ; c. 12 January 251 – 17 January 356), was a Christian monk from Egypt, revered since his death as a saint. He is d ...

specialized in treating ergotism victims with balms containing tranquilizing and circulation-stimulating plant extracts; they were also skilled in amputations. The common name for ergotism is "St. Anthony's Fire", in reference to monks who cared for victims as well as symptoms, such as severe burning sensations in the limbs. These are caused by effects of ergot alkaloids on the

vascular system The blood circulatory system is a system of organs that includes the heart, blood vessels, and blood which is circulated throughout the entire body of a human or other vertebrate. It includes the cardiovascular system, or vascular system, tha ...

due to

vasoconstriction Vasoconstriction is the narrowing of the blood vessels resulting from contraction of the muscular wall of the vessels, in particular the large arteries and small arterioles. The process is the opposite of vasodilation, the widening of blood vess ...

of blood vessels, sometimes leading to gangrene and loss of limbs due to severely restricted blood circulation. The neurotropic activities of the ergot alkaloids may also cause hallucinations and attendant irrational behaviour, convulsions, and even death. Other symptoms include strong

uterine The uterus (from Latin ''uterus'', plural ''uteri'') or womb () is the organ in the reproductive system of most female mammals, including humans that accommodates the embryonic and fetal development of one or more embryos until birth. The ...

contractions,

nausea Nausea is a diffuse sensation of unease and discomfort, sometimes perceived as an urge to vomit. While not painful, it can be a debilitating symptom if prolonged and has been described as placing discomfort on the chest, abdomen, or back of the ...

seizure An epileptic seizure, informally known as a seizure, is a period of symptoms due to abnormally excessive or synchronous neuronal activity in the brain. Outward effects vary from uncontrolled shaking movements involving much of the body with l ...

s, and unconsciousness. Since the Middle Ages, controlled doses of ergot were used to induce

abortion Abortion is the termination of a pregnancy by removal or expulsion of an embryo or fetus. An abortion that occurs without intervention is known as a miscarriage or "spontaneous abortion"; these occur in approximately 30% to 40% of pre ...

s and to stop maternal bleeding after childbirth.Untersuchungen über das Verhalten der Secalealkaloide bei der Herstellung von Mutterkornextrakten. Labib Farid Nuar. Universität Wien - 1946 - (University of Vienna) Ergot alkaloids are also used in products such as

Cafergot Caffeine/ergotamine (trade name Cafergot) is the proprietary name of a medication consisting of ergotamine tartrate and caffeine. This combination is used for the treatment of headaches, such as migraine headache. Use Correct timing of use ...

(containing

caffeine Caffeine is a central nervous system (CNS) stimulant of the methylxanthine class. It is mainly used recreationally as a cognitive enhancer, increasing alertness and attentional performance. Caffeine acts by blocking binding of adenosine to ...

and

) to treat migraine headaches. Ergot extract is no longer used as a

pharmaceutical A medication (also called medicament, medicine, pharmaceutical drug, medicinal drug or simply drug) is a drug used to diagnose, cure, treat, or prevent disease. Drug therapy (pharmacotherapy) is an important part of the medical field an ...

preparation. Ergot contains no

lysergic acid diethylamide Lysergic acid diethylamide (LSD), also known colloquially as acid, is a potent psychedelic drug. Effects typically include intensified thoughts, emotions, and sensory perception. At sufficiently high dosages LSD manifests primarily mental, vi ...

(LSD) but rather ergotamine, which is used to synthesize

, an analog of and precursor for synthesis of LSD. Moreover, ergot sclerotia naturally contain some amounts of lysergic acid.

Culture

Potato dextrose agar Potato dextrose agar (BAM Media M127
from the U.S.

, wheat seeds or oat flour are suitable substrates for growth of the fungus in the laboratory. Agricultural production of Claviceps purpurea on rye is used to produce ergot alkaloids. Biological production of ergot alkaloids is also carried out by saprophytic cultivations.

Speculations

During the

Middle Ages In the history of Europe, the Middle Ages or medieval period lasted approximately from the late 5th to the late 15th centuries, similar to the post-classical period of global history. It began with the fall of the Western Roman Empire ...

, human poisoning due to the consumption of rye bread made from ergot-infected grain was common in Europe. These epidemics were known as Saint Anthony's fire, or ''ignis sacer''. Gordon Wasson proposed that the psychedelic effects were the explanation behind the festival of Demeter at the

Eleusinian Mysteries The Eleusinian Mysteries ( el, Ἐλευσίνια Μυστήρια, Eleusínia Mystḗria) were initiations held every year for the cult of Demeter and Persephone based at the Panhellenic Sanctuary of Elefsina in ancient Greece. They are th ...

, where the initiates drank

kykeon Kykeon (, ; from , "to stir, to mix") was an Ancient Greek drink of various descriptions. Some were made mainly of water, barley and naturally occurring substances. Others were made with wine and grated cheese. It is widely believed that kykeon us ...

''.''

Linnda R. Caporael Linnda Caporael is a professor at the Science and Technology Studies Department at Rensselaer Polytechnic Institute. Educational background Linnda R. Caporael is a professor at Rensselaer Polytechnic Institute in the department of Technical Studie ...

posited in 1976 that the hysterical symptoms of young women that had spurred the

Salem witch trials The Salem witch trials were a series of hearings and prosecutions of people accused of witchcraft in colonial Massachusetts between February 1692 and May 1693. More than 200 people were accused. Thirty people were found guilty, 19 of whom w ...

had been the result of consuming ergot-tainted rye. However, her conclusions were later disputed by Nicholas P. Spanos and Jack Gottlieb, after a review of the historical and medical evidence. Other authors have likewise cast doubt on ergotism having been the cause of the Salem witch trials. The

Great Fear The Great Fear (french: Grande Peur) was a general panic that took place between 22 July to 6 August 1789, at the start of the French Revolution. Rural unrest had been present in France since the worsening grain shortage of the spring, ...

in France during the

Revolution In political science, a revolution (Latin: ''revolutio'', "a turn around") is a fundamental and relatively sudden change in political power and political organization which occurs when the population revolts against the government, typically due ...

has also been linked by some historians to the influence of ergot. British author John Grigsby claims that the presence of ergot in the stomachs of some of the so-called 'bog-bodies' (

Iron Age The Iron Age is the final epoch of the three-age division of the prehistory and protohistory of humanity. It was preceded by the Stone Age ( Paleolithic, Mesolithic, Neolithic) and the Bronze Age ( Chalcolithic). The concept has been mostl ...

human remains from peat bogs N E Europe such as

Tollund Man The Tollund Man (died 405–380 BC) is a naturally Mummy, mummified corpse of a man who lived during the 5th century BC, during the period characterised in Scandinavia as the Pre-Roman Iron Age. He was found in 1950, preserved as a bog body, ne ...

), reveals that ergot was once a ritual drink in a prehistoric fertility cult akin to the

cult of ancient

Greece Greece,, or , romanized: ', officially the Hellenic Republic, is a country in Southeast Europe. It is situated on the southern tip of the Balkans, and is located at the crossroads of Europe, Asia, and Africa. Greece shares land borders ...

. In his book Beowulf and Grendel he argues that the Anglo-Saxon poem Beowulf is based on a memory of the quelling of this fertility cult by followers of Odin. He states that Beowulf, which he translates as ''barley-wolf'', suggests a connection to ergot which in German was known as the 'tooth of the wolf'. An outbreak of violent hallucinations among hundreds of residents of Pont St. Esprit in 1951 in the south of France has also been attributed to ergotism. Seven people died.

References

External links

Claviceps purpurea - Ergot Alkaloid

* ttp://content.nejm.org/cgi/content/short/356/1/29 New England Journal of Medicine - Dopamine Agonists and the Risk of Cardiac-Valve Regurgitation
Linnda Caporeal's article "Ergotism: The Satan Loosed in Salem?
{{Taxonbar, from=Q217227 Clavicipitaceae Fungi of Europe Psychoactive fungi Natural sources of lysergamides Medicinal fungi Parasitic fungi Fungal plant pathogens and diseases Cereal diseases Barley diseases Rye diseases Triticale diseases Wheat diseases Abortifacients Soma (drink) Fungi described in 1823 Taxa named by Elias Magnus Fries

Life cycle

Intraspecific variations

Host range

Pooideae

Arundinoideae

Chloridoideae

Panicoideae

Epidemiology

Effects

Culture

Speculations

See also

References

External links