Fungus Claviceps Purpurea Research Articles

Protective Effect of Ergothioneine against Oxidative Stress-Induced Chondrocyte Death.

Reactive oxygen species (ROS) induce oxidative stress in cells and are associated with various diseases, including autoimmune diseases. Ergothioneine (EGT) is a natural amino acid derivative derived from the ergot fungus and has been reported to exhibit an effective antioxidant function in many models of oxidative stress-related diseases. Recently, mutations in OCTN1, a membrane transporter of EGT, have been reported to be associated with rheumatoid arthritis. Therefore, we investigated the chondrocyte-protective function of EGT using a model of oxidative stress-induced injury of chondrocytes by hydrogen peroxide (H2O2). Human chondrocytes were subjected to oxidative stress induced by H2O2 treatment, and cell viability, the activity of lactate dehydrogenase (LDH) released into the medium, dead cell ratio, intracellular ROS production, and mitochondrial morphology were assessed. EGT improved chondrocyte viability and LDH activity in the medium and strongly suppressed the dead cell ratio. EGT also exerted protective effects on intracellular ROS production and mitochondrial morphology. These results provide evidence to support the protective effects of EGT on chondrocytes induced by oxidative stress.

Chromosome-level draft genome sequences of three isolates of the toxigenic fungus Claviceps purpurea showing structural rearrangements.

The whole genomes of three Claviceps purpurea strains were sequenced using Oxford Nanopore Technologies' MinION and assembled into complete, chromosome-level assemblies. The C. purpurea genome consists of eight conserved chromosomes, with evidence of inter-chromosomal structural rearrangements between strains.

Ergotamine Stimulates Human 5-HT4-Serotonin Receptors and Human H2-Histamine Receptors in the Heart

Ergotamine (2'-methyl-5'α-benzyl-12'-hydroxy-3',6',18-trioxoergotaman) is a tryptamine-related alkaloid from the fungus Claviceps purpurea. Ergotamine is used to treat migraine. Ergotamine can bind to and activate several types of 5-HT1-serotonin receptors. Based on the structural formula of ergotamine, we hypothesized that ergotamine might stimulate 5-HT4-serotonin receptors or H2-histamine receptors in the human heart. We observed that ergotamine exerted concentration- and time-dependent positive inotropic effects in isolated left atrial preparations in H2-TG (mouse which exhibits cardiac-specific overexpression of the human H2-histamine receptor). Similarly, ergotamine increased force of contraction in left atrial preparations from 5-HT4-TG (mouse which exhibits cardiac-specific overexpression of the human 5-HT4-serotonin receptor). An amount of 10 µM ergotamine increased the left ventricular force of contraction in isolated retrogradely perfused spontaneously beating heart preparations of both 5-HT4-TG and H2-TG. In the presence of the phosphodiesterase inhibitor cilostamide (1 µM), ergotamine 10 µM exerted positive inotropic effects in isolated electrically stimulated human right atrial preparations, obtained during cardiac surgery, that were attenuated by 10 µM of the H2-histamine receptor antagonist cimetidine, but not by 10 µM of the 5-HT4-serotonin receptor antagonist tropisetron. These data suggest that ergotamine is in principle an agonist at human 5-HT4-serotonin receptors as well at human H2-histamine receptors. Ergotamine acts as an agonist on H2-histamine receptors in the human atrium.

Winter rye cultivars moderately resistant to ergot

Background. Cereal ergot caused by the fungus Claviceps purpurea (Fr.) Tul. is a progressive disease of winter rye. There are no rye cultivars resistant to the disease, and breeding methods of protection have not been developed in Russia.Materials and methods. The material for the research included 97 winter rye cultivars. A biochemical analysis of the sclerotia of the fungus was carried out, the composition and content of ergot alkaloids (EA) in the sclerotia of C. purpurea from the Kirov population were studied, and the relationship between the biometry of sclerotia and the EA content, toxicity and pathogenicity of C. purpurea was analyzed. Well-known methods of resistance assessment and EA analysis were applied.Results and conclusions. Fourteen cultivars least affected by the pathogen were identified: ‘Flora’, ‘Kiprez’, ‘Grafinya’, ‘Lika’, ‘Batist’, ‘Simfoniya’, ‘Garmoniya’, ‘Sadko’, ‘Parom’, ‘Virazh’, ‘Saratovskaya 7’, ‘Volkhova’, ‘Novaya Era’, and ‘Podarok’. They can be used in breeding for ergot resistance. Three types of EA were identified in C. purpurea sclerotia: ergocristine, ergotamine, and its stereoisomer ergocristinine. Cvs. ‘Lika’, ‘Simfoniya’ and ‘Garmoniya’ were the least affected by ergot, and the sclerotia formed on the plants of these cultivars did not accumulate EA. A significant (r = 0.50–0.60) correlation was found between lesions and biometric parameters of C. purpurea sclerotia, and between grain contamination with sclerotia and their biometrics (r = 0.63– 0.78). A weak positive correlation (r = 0.22) was detected between the toxicity and pathogenicity of C. purpurea. A negative correlation was established between the weight of sclerotia and the accumulation of EA in them (r = –0.46), which indicated the biological danger of small sclerotia that got into the seed and food batches of grain.

Methods of Lysergic Acid Synthesis-The Key Ergot Alkaloid.

Ergot is the spore form of the fungus Claviceps purpurea. Ergot alkaloids are indole compounds that are biosynthetically derived from L-tryptophan and represent the largest group of fungal nitrogen metabolites found in nature. The common part of ergot alkaloids is lysergic acid. This review shows the importance of lysergic acid as a representative of ergot alkaloids. The subject of ergot and its alkaloids is presented, with a particular focus on lysergic acid. All methods of total lysergic acid synthesis-through Woodward, Hendrickson, and Szantay intermediates and Heck coupling methods-are presented. The topic of biosynthesis is also discussed.

Pre-invasion assessment on African invasive grasses revealed five new species of ergot fungi, Claviceps section Pusillae

Ergot, the genus Claviceps comprises several deeply diverged lineages, recently classified as sections. Among them, the section Pusillae, is the most speciose, with a centre of distribution in Africa but occurring worldwide, often as a consequence of its invasive potential. This section includes the most severe plant pathogens such as Claviceps africana and C. gigantea, responsible for toxicoses and a significant reduction in the seed yields of Sorghum and Zea. In this study we surveyed ergot diversity in South Africa, focusing on grasses native to this region, but known for their high potential of invasiveness. The revision based on molecular and phenotypic markers revealed 16 species, with a high proportion of undescribed diversity, confirming Africa as a hot spot for this section. Five new species, Claviceps tulasnei, Claviceps eulaliae, Claviceps hypertheliae, Claviceps fredericksoniae and Claviceps arundinellae were described from Setaria, Eulalia, Hyperthelia, Miscanthus and Arundinella respectively. Claviceps texensis infecting Cenchrus, previously only identified from the same host in Texas, USA, was confirmed to be present in Africa, which is assumed to be its primary area of distribution. In addition, the host grass genus Anthephora is newly reported as a host of Claviceps digitariae. The most of the taxa were negligible concerning alkaloid production, with the exception of C. fredericksoniae, which is a sister of potent alkaloid producer C. africana, and produces mainly DH-ergosine, together with traces of DH-ergocornine. The host/parasite associations within Pusillae section is very narrow, suggesting that co-speciation is the major speciation driver in this group. Host grasses of the described species are already recognised invasive species and their ovarial parasites need to be monitored. This is highlighted by the fact that all Pusillae produced air-borne secondary conidia, which is autapomorphy of this section and considered to be important for their invasive abilities.

Awareness of people living in Sagure District, Arsi, Ethiopia about ergot fungus (Claviceps purpurea) and ergotism

Ergot is a plant parasitic fungus that belongs to the genus Claviceps, and ergotism is a poisoning caused by secondary metabolites produced mainly by the ergot fungus (Claviceps purpurea). The presence of ergot fungi in the farmers’ field was surveyed, and ergot sclerotia were clearly observed in the farmers’ fields on wild oat plants. A cross-sectional study was therefore conducted in three Kebeles of the Sagure District (Kechema Murkicha, Digelu Kidame and Mankula Negele), near Asela town, Ethiopia, to assess awareness of the residents about ergot fungus and ergotism. From a total of 385 study participants only 100 (26%), knew what ergot and ergotism stand for. Thirty-one percent of the study participants described the most common symptoms of the ergot poisoning as ‘cutting off legs’ and removing wild oats (Avena abyssinica), the host for the ergot fungus, as the main method of prevention of the disease. Among the socio-demographic factors, education level was found to be significantly associated with the knowledge of ergot (p < 0.001), where participants from secondary education and above had better knowledge about ergot fungus and ergotism (cor: 2.5, 95% CI:1.34 – 6.22). From binary logistic regression model fitted, study site has statistically significant association with knowledge about ergot (AOR: 5.34, 95% CI:3.25 – 8.43, p< 0.001). In conclusion, though the fungus was prevalent in the farmers’ fields, majority of the study participants were not aware of ergot fungus and ergotism, thus there is a need to create awareness about the fungus and the disease in order to prevent possible future disease outbreaks.

The 168-year taxonomy of Claviceps in the light of variations: From three morphological species to four sections based on multigene phylogenies

Ergot fungi produce toxic sclerotia that have significant impacts on the agricultural, food and pharmaceutical industries. These fungi were classified in various genera (such as Sclerotium clavus, or Spermoedia clavus) before Tulasne, in 1853, erected Claviceps and described three species based on variations in morphology and host ranges, viz. C. purpurea, C. microcephala, and C. nigricans. Since then, knowledge regarding the biological, clinical, and pharmaceutical perspectives of ergot has accumulated rapidly. However, a serious taxonomic examination was lacking until Langdon’s revision accepted 25 species in 1952. That was followed by intensive regional studies by Loveless in the 1960s for Rhodesia (now Zimbabwe, Africa), and Tanda in Japan (1970s–1990s). More species names were reported and currently over 90 named taxa (species, varieties) are recorded in fungal name repositories (Mycobank and Index Fungorum). Most species were described based on morphological characteristics (sclerotia, ascomata and conidia) and host ranges. Some were characterized by their alkaloid profiles. Recently, DNA multi-locus sequence analyses (MLSA) were applied to resolve species complexes. For instance, the C. purpurea complex was separated into four species, and additional new species were recognized from South Africa and Canada. Infra- and supra-specific level genetic variations were identified via multi-locus and genomic studies. Based on five-locus phylogenies, Píchová and colleagues separated Claviceps into four sections: C. sect. Claviceps, C. sect. Citrinae, C. sect. Paspalorum and C. sect. Pusillae, for 60 species. Among these sections, several doubtful species names require clarification. Careful research on type specimens combined with molecular analyses is essential for clarifying these names.

Rapid sourdough yeast identification using panfungal PCR combined with high resolution melting analysis

The microbial composition of the sourdough starter affects the sourdough bread properties. Therefore, it is crucial to find a tool for rapid, time-saving, and economical identification of the sourdough microbiota. We focused on the rapid identification of sourdough yeasts. We designed a panfungal real time-PCR targeting the ITS2 region (ITS-amplicon) and a fragment of D1/D2 region of 26S rRNA gene (U-amplicon) and used high resolution melting analysis (HRM) for subsequent species identification. The sensitivity and specificity of our method were tested on the reference yeast cultures. We obtained divergent melting peaks (Tm). The further analysis of melt curves suggests the possibility to discriminate yeasts on the genus- and some on species-specific level in the mixed sample. The applicability of this method in routine practice was evaluated on nine sourdough samples. Revealed melt curves of U-amplicons were predominantly characteristic of the sourdough. The evaluation of the Tm and the shape of the melt curve was used to assess the sourdough yeasts. Additionally, using the HRM-PCR method the contamination with the ergot fungus DNA was revealed. Our data showed HRM-PCR is a simple, rapid, and inexpensive tool useful in identifying sourdough yeasts.

Heterologous Synthesis and Secretion of Ricinoleic Acid in Starmerella bombicola with Sophorolipid as an Intermediate.

Ricinoleic acid (RA) is a long-chain hydroxy fatty acid produced from castor bean that is used in the manufacturing of a variety of industrial products. The demand for RA keeps increasing due to its broad applications. However, due to the presence of a potent toxin ricin, the native oilseed plant is not an ideal source for hydroxy fatty acid production. Although there have been significant efforts on engineering different microorganisms for heterologous production of RA, all had very limited success. The main reason for this is the exhibited toxicity of the intracellularly accumulated RA. To avoid this issue, we genetically modified a Starmerella bombicola strain by engineering its native sophorolipid production pathway to direct the synthesized RA bound with sophorolipid to be secreted out of the cell, followed by acid hydrolysis to recover RA. The engineered S. bombicola strain expressing the heterologous codon-optimized oleate hydroxylase-encoding gene from ergot fungus Claviceps purpurea resulted in a record production titer of RA at about 2.96 g/L. Thus, this work highlights a new strategy to produce a high level of hydroxy fatty acids in engineered yeast through a sophorolipid intermediate, enabling a new biocatalysis platform for the future.

Reconstituting the complete biosynthesis of D-lysergic acid in yeast

The ergot alkaloids are a class of natural products known for their pharmacologically privileged molecular structure that are used in the treatment of neurological ailments, such as Parkinsonism and dementia. Their synthesis via chemical and biological routes are therefore of industrial relevance, but suffer from several challenges. Current chemical synthesis methods involve long, multi-step reactions with harsh conditions and are not enantioselective; biological methods utilizing ergot fungi, produce an assortment of products that complicate product recovery, and are susceptible to strain degradation. Reconstituting the ergot alkaloid pathway in a strain strongly amenable for liquid fermentation, could potentially resolve these issues. In this work, we report the production of the main ergoline therapeutic precursor, D-lysergic acid, to a titre of 1.7 mg L−1 in a 1 L bioreactor. Our work demonstrates the proof-of-concept for the biological production of ergoline-derived compounds from sugar in an engineered yeast chassis.

Materials on the issue of ergot poisoning

Everyone knows the black horns that often appear on the ears of rye, instead of grains, which represent the sclerotia of the parasitic fungus Claviceps purpurea. Abundant rains during the period of grain ripening, as well as hailstorms, contribute to a more abundant infection of rye and, to a lesser extent, other grain crops with the aforementioned ergot horns. All these conditions were extremely bright and intense in the Novo-Georgievsk region, where we traced the epidemic of ergotism that arose there. By the beginning of the harvesting campaign, there were no instructions from agronomists about the contamination of grain with ergot horns. On July 21 (32), the harvesting of a new crop began, and on July 25, we already faced the fact of a massive ergotism disease. The symptomatology of the disease was as follows: severe weakness, vomiting, diarrhea, headache, slight flatulence and slight coldness of the arms and legs. But all these poisonings were relatively mild, outpatient.

Epichloë Endophyte-Promoted Seed Pathogen Increases Host Grass Resistance Against Insect Herbivory.

Plants host taxonomically and functionally complex communities of microbes. However, ecological studies on plant–microbe interactions rarely address the role of multiple co-occurring plant-associated microbes. Here, we contend that plant-associated microbes interact with each other and can have joint consequences for higher trophic levels. In this study we recorded the occurrence of the plant seed pathogenic fungus Claviceps purpurea and aphids (Sitobion sp.) on an established field experiment with red fescue (Festuca rubra) plants symbiotic to a seed transmitted endophytic fungus Epichloë festucae (E+) or non-symbiotic (E–). Both fungi are known to produce animal-toxic alkaloids. The study was conducted in a semi-natural setting, where E+ and E– plants from different origins (Spain and Northern Finland) were planted in a randomized design in a fenced common garden at Kevo Subarctic Research Station in Northern Finland. The results reveal that 45% of E+ plants were infected with Claviceps compared to 31% of E– plants. Uninfected plants had 4.5 times more aphids than Claviceps infected plants. By contrast, aphid infestation was unaffected by Epichloë symbiosis. Claviceps alkaloid concentrations correlated with a decrease in aphid numbers, which indicates their insect deterring features. These results show that plant mutualistic fungi can increase the infection probability of a pathogenic fungus, which then becomes beneficial to the plant by controlling herbivorous insects. Our study highlights the complexity and context dependency of species–species and multi-trophic interactions, thus challenging the labeling of species as plant mutualists or pathogens.

Mycobiota of rye seeds infected with ergot fungi

Mycobiota of rye seeds infected with ergot fungi

Production of Ergot Alkaloids by the Japanese Isolate <i>Claviceps purpurea</i> var. <i>agropyri</i> on Rice Medium

Ergot alkaloids (EAs) are secondary metabolites produced by ergot fungi (e.g., Claviceps purpurea), which are parasites of Gramineae grasses. EAs and their analogs are used to treat migraine, postpartum uterine bleeding, and Parkinson's syndrome. Recent studies have reported additional new bioactive activities of EAs and their analogs, making them essential compounds for drug development, drug repositioning, and clinical applications. EAs are produced industrially by field cultivation of ergot or liquid fermentation in the mycelial phase, but there are few published studies of the production of EAs by cereal culture and thus this approach is poorly understood. This study searched for Claviceps strains that produce EAs cultured artificially in the mycelial phase, then the selected strains were cultured on cereal media (white rice, brown rice, and rye) to examine their ability to produce EAs on each medium. C. purpurea var. agropyri produced the Clavine-type EAs pyroclavine (1), festuclavine (2), and agroclavine (3) in the mycelial phase. When cultured with white rice, brown rice, or rye, C. purpurea var. agropyri produced 1 - 3 on all cereal media. The total amount of 1 - 3 in each cereal medium (150 g of cereal per Roux flask) was 2220.5 ± 564.1 μg for white rice, 920.0 ± 463.6 μg for brown rice, and 595.4 ± 52.1 μg for rye. The white rice medium supported the highest production of 1 - 3, with the total amount of EAs (150 g of white rice per Roux flask) being about 34 times higher than that in the T25 liquid medium (190 mL per 1 L Erlenmeyer flask) (equivalent amount per flask).

Изучение экзогенных репродуктивных структур аксенической культуры гриба спорыньи (Claviceps Purpurea) в процессе бесполого размножения

Claviceps purpurea (Fries) Tulasne are used in parasitic and saprophytic cultures to obtain ergoalkaloids (EA), including ergocriptine. Ergocryptine has a variety of pharmacological effects, including reducing the secretion of prolactin and somatotropic hormone, suppresses physiological lactation. It also has an antiparkinsonian effect, and ergocriptine increases motor activity. Ergocriptine- based drugs are used in the treatment of hyperprolactinemia and adenomas that produce prolactin, infertility in men and women. The importance of C. purpurea for medicine requires the study of reproduction characteristics of the fungus cultivated in different areas and substrates. The results of studying features of the exogenous reproductive structures the ergocriptine line fungus Claviceps purpurea in saprophytic condition, as well as the composition of ergot alkaloids in sclerotia and in samples of C. purpurea mycelia, are presented. The exogenous reproductive structures play a decisive role in artificial infection in saprophytic and parasitic conditions. The aim of the work was to study the growth and reproductive in saprophytic of the line of the fungus parasite C. purpurea producing ergocriptine in saprophytic conditions under the conditions of saprophytic cultivation (by surface and submerged methods cultivation). It was found that the growth rate of conidia, including width and length, were faster under the conditions of saprophytic cultivation of C. purpurea on the surface of an agar growth medium. The features of the dynamics of conidioproduction in submerged and surface cultivation on an agar growth medium. It has been shown that the HPLC method, in comparison with TLC for the analysis of ergocriptine, is more effective, since it allows the determination of its insignificant content.

Mining Indole Alkaloid Synthesis Gene Clusters from Genomes of 53 Claviceps Strains Revealed Redundant Gene Copies and an Approximate Evolutionary Hourglass Model

Ergot fungi (Claviceps spp.) are infamous for producing sclerotia containing a wide spectrum of ergot alkaloids (EA) toxic to humans and animals, making them nefarious villains in the agricultural and food industries, but also treasures for pharmaceuticals. In addition to three classes of EAs, several species also produce paspaline-derived indole diterpenes (IDT) that cause ataxia and staggers in livestock. Furthermore, two other types of alkaloids, i.e., loline (LOL) and peramine (PER), found in Epichloë spp., close relatives of Claviceps, have shown beneficial effects on host plants without evidence of toxicity to mammals. The gene clusters associated with the production of these alkaloids are known. We examined genomes of 53 strains of 19 Claviceps spp. to screen for these genes, aiming to understand the evolutionary patterns of these genes across the genus through phylogenetic and DNA polymorphism analyses. Our results showed (1) varied numbers of eas genes in C. sect. Claviceps and sect. Pusillae, none in sect. Citrinae, six idt/ltm genes in sect. Claviceps (except four in C. cyperi), zero to one partial (idtG) in sect. Pusillae, and four in sect. Citrinae, (2) two to three copies of dmaW, easE, easF, idt/ltmB, itd/ltmQ in sect. Claviceps, (3) frequent gene gains and losses, and (4) an evolutionary hourglass pattern in the intra-specific eas gene diversity and divergence in C. purpurea.

Simultaneous Determination of Ergot Alkaloids in Swine and Dairy Feeds Using Ultra High-Performance Liquid Chromatography-Tandem Mass Spectrometry.

Ergot alkaloids (EAs) are mycotoxins mainly produced by the fungus Claviceps purpurea. EAs are known to affect the nervous system and to be vasoconstrictors in humans and animals. This work presents recent advances in swine and dairy feeds regarding 11 major EAs, namely ergometrine, ergosine, ergotamine, ergocornine, ergocryptine, ergocristine, ergosinine, ergotaminine, ergocorninine, ergocryptinine, and ergocristinine. A reliable, sensitive, and accurate multiple mycotoxin method, based on extraction with a Mycosep 150 multifunctional column prior to analysis using UHPLC-MS/MS, was validated using samples of swine feed (100) and dairy feed (100) for the 11 targeted EAs. Based on the obtained validation results, this method showed good performance recovery and inter-day and intra-day precision that are in accordance with standard criteria to ensure reliable occurrence data on EA contaminants. More than 49% of the swine feed samples were contaminated with EAs, especially ergocryptine(-ine) (40%) and ergosine (-ine) and ergotamine (-ine) (37%). However, many of the 11 EAs were not detectable in any swine feed samples. In addition, there were contaminated (positive) dairy feed samples, especially for ergocryptine (-ine) (50%), ergosine (-ine) (48%), ergotamine (-ine), and ergocristine (-ine) (49%). The mycotoxin levels in the feed samples in this study almost complied with the European Union regulations.

Updated review on Extraction, Isolation and Quantitative estimation of Ergot Alkaloids

Ergot Alkaloids are potent α-blockers that cause direct smooth muscle contraction. They are products of fungi in the genus Claviceps. The most prominent member of this group is Claviceps purpurea (rye ergot fungus). Their common sources include Rye, bread as well as other grains. These are nitrogen derived- natural substances which are grouped under indole alkaloids. These ergot alkaloids are a diverse category of secondary metabolites that have been classified into 3 groups as Clavines, Amides of lysergic acid, Ergopeptines and Lactum ergot alkaloids based on their bond arrangement. They contaminate a large variety of cereals such as rye triticale, wheat and barley. In this present review, basic information regarding the ergots along with their chemistry, extraction, purification and isolation procedures for ergot alkaloids were focused, that helps to produce a purified crude extract that is taken for chromatographic analysis. This review also provides detailed informations on the chromatographic approaches for the ergot alkaloids estimations such as TLC, HPLC, HPTLC, UPLC /UHPLC, LCMS, GCMS with different detection techniques like Mass spectrometry and Fluorescence detection which was done in the past decade and also provides information regarding the pharmacological activity of ergot alkaloids like its application in the treatment of severe, throbbing headaches such as migraine, cluster headaches and also other therapeutic applications.

Insights into Ergochromes of the Plant Pathogen Claviceps purpurea.

Claviceps purpurea is an ergot fungus known for its neurotropic alkaloids, which have been identified as the main cause of ergotism, a livestock and human disease triggered by ergot consumption. Tetrahydroxanthone dimers, the so-called ergopigments, presumably also contribute to this toxic effect. Overexpression of the cluster-specific transcription factor responsible for the formation of these pigments in C. purpurea led to the isolation of three new metabolites (8-10). The new pigments were characterized utilizing HRMS, NMR techniques, and CD spectroscopy and shown to be xanthone dimers. Secalonic acid A and its 2,4'- and 4,4'-linked isomers were also isolated, and their absolute configuration was investigated. The contribution of secalonic acid A, its isomers, and new metabolites to the toxicity of C. purpurea was investigated in HepG2 and CCF-STTG1 cells. Along with cytotoxic properties, secalonic acid A was found to inhibit topoisomerase I and II activity.