| new insights into ergot alkaloid biosynthesis in claviceps purpurea: an agroclavine synthase easg catalyses, via a non-enzymatic adduct with reduced glutathione, the conversion of chanoclavine-i aldehyde to agroclavine. | ergot alkaloids are indole derivatives with diverse structures and biological activities. they are produced by a wide range of fungi with claviceps purpurea as the most important producer for medical use. chanoclavine-i aldehyde is proposed as a branch point via festuclavine or pyroclavine to clavine-type alkaloids in trichocomaceae and via agroclavine to ergoamides and ergopeptines in clavicipitaceae. here we report the conversion of chanoclavine-i aldehyde to agroclavine by easg from claviceps ... | 2011 | 21494745 |
| [in process citation]. | the frequent epidemics of ergotism were called holy fire or st-antony's fire in the middle ages, because of the burning sensations resulting in gangrene of limbs. it was caused by eating rye bread contaminated with the fungus claviceps purpurea. the hospitable order of st-antony was founded near vienne in france with 300 establishements in europe until 1777. in coptic and byzantine art st-antony is the father of the monks, whereas in occident he is the the master of fire, thaumaturgic, resulting ... | 2010 | 21598563 |
| investigation of the metabolism of ergot alkaloids in cell culture by fourier transformation mass spectrometry. | ergot alkaloids are known toxic secondary metabolites of the fungus claviceps purpurea occurring in various grains, especially rye products. the liver is responsible for converting the ergot alkaloids into metabolites; however, the toxic impact of these end products of metabolism is still unknown. the aim of this study was to analyze the metabolism of ergot alkaloids in colon and liver cell lines (ht-29, hepg2), as well as in human primary renal cells (rptec). it was shown that cells in vitro ar ... | 2011 | 21650459 |
| deletion of mid1, a putative stretch-activated calcium channel in claviceps purpurea, affects vegetative growth, cell wall synthesis and virulence. | the putative claviceps purpurea homologue of the saccharomyces cerevisiae stretch-activated calcium ion channel mid1 was investigated for its role in vegetative growth, differentiation and pathogenicity on rye (secale cereale). gene replacement mutants of cl. purpurea mid1 were not affected in polar growth and branching in axenic culture but showed a significantly reduced growth rate. the growth defect could not be complemented by ca(2+) supplementation, in contrast to mid1 mutants in yeast, but ... | 2009 | 19762439 |
| lumi-ergometrine--structural identification and occurrence in sclerotia. | the fungus claviceps purpurea grows on grasses and cereal grains and produces six predominant ergot alkaloids. these toxic substances undergo different transformation reactions during storage and cereal processing. one of these reactions is the addition of water to a double bond in the ergoline skeleton. since light is required for this process, the substances formed were named lumi-ergot alkaloids. from these, a new asymmetric carbon and consequently two epimers with different polarities are fo ... | 2011 | 23605983 |
| in vitro pathogenicity assay for the ergot fungus claviceps purpurea. | the pathogenic development of the biotrophic ergot fungus claviceps purpurea is strictly limited to the ovary of grasses. early colonization stages occur within a defined spatio-temporal course of events, including the directed growth to the vascular tissue for nutrient supply. to characterize mutant strains with putative defects in pathogenicity, the close observation of the infection pathway is therefore indispensable. here, we describe the establishment of a new pathogenicity assay, based on ... | 2006 | 16483754 |
| identification of the cytochrome p450 monooxygenase that bridges the clavine and ergoline alkaloid pathways. | clavines and d-lysergic acid-derived alkaloid amides and alkaloid peptides are two different families of compounds that have the indole-derived tetracyclic metergoline ring system in common. previous work has shown that d-lysergic acid is biosynthetically derived from clavine alkaloids. recent cloning and analysis of the ergot alkaloid biosynthesis gene cluster from the d-lysergic acid peptide (ergopeptines)-producing claviceps purpurea, has shown that it most probably contains all genes necessa ... | 2006 | 16538694 |
| a complex ergovaline gene cluster in epichloe endophytes of grasses. | clavicipitaceous fungal endophytes of the genera epichloë and neotyphodium form symbioses with grasses of the subfamily pooideae, in which they can synthesize an array of bioprotective alkaloids. some strains produce the ergopeptine alkaloid ergovaline, which is implicated in livestock toxicoses caused by ingestion of endophyte-infected grasses. cloning and analysis of a nonribosomal peptide synthetase (nrps) gene from neotyphodium lolii revealed a putative gene cluster for ergovaline biosynthes ... | 2007 | 17308187 |
| phylogenetic evidence for an animal pathogen origin of ergot and the grass endophytes. | grass-associated fungi (grass symbionts) in the family clavicipitaceae (ascomycota, hypocreales) are species whose host range is restricted to the plant family poaceae and rarely cyperaceae. the best-characterized species include claviceps purpurea (ergot of rye) and neotyphodium coenophialum (endophyte of tall fescue). they have been the focus of considerable research due to their importance in agricultural and grassland ecosystems and the diversity of their bioactive secondary metabolites. her ... | 2007 | 17402984 |
| primary structure, regioselectivity, and evolution of the membrane-bound fatty acid desaturases of claviceps purpurea. | two cdnas with sequence similarity to fatty acid desaturase genes were isolated from the phytopathogenic fungus, claviceps purpurea. the predicted amino acid sequences of the corresponding genes, named cpdes12 and cpdesx, share 87% identity. phylogenetic analysis indicates that cpdes12 and cpdesx arose by gene duplication of an ancestral delta(12)-desaturase gene after the divergence of nectriaceae and clavicipitaceae. functional expression of cpdes12 and cpdesx in yeast (saccharomyces cerevisia ... | 2007 | 17510052 |
| use of a nonhomologous end joining deficient strain (deltaku70) of the ergot fungus claviceps purpurea for identification of a nonribosomal peptide synthetase gene involved in ergotamine biosynthesis. | the ergot fungus claviceps purpurea uses mainly the nonhomologous-end-joining (nhej) system for integration of exogenous dna, leading to a low frequency of homologous integration (1-2%). to improve gene targeting efficiency we deleted the c. purpurea ku70 gene in two different strains: the pathogenic strain 20.1 and the apathogenic, ergot alkaloid producing strain p1. the mutants were not impaired in vegetative and pathogenic development nor alkaloid production. gene targeting efficiency was sig ... | 2008 | 17560817 |
| comparison of ergot alkaloid biosynthesis gene clusters in claviceps species indicates loss of late pathway steps in evolution of c. fusiformis. | the grass parasites claviceps purpurea and claviceps fusiformis produce ergot alkaloids (ea) in planta and in submerged culture. whereas ea synthesis (eas) in c. purpurea proceeds via clavine intermediates to lysergic acid and the complex ergopeptines, c. fusiformis produces only agroclavine and elymoclavine. in c. purpurea the eas gene (eas) cluster includes dmaw (encoding the first pathway step), cloa (elymoclavine oxidation to lysergic acid), and the lpsa/lpsb genes (ergopeptine formation). w ... | 2007 | 17720822 |
| guttation fluid: effects on growth of claviceps purpurea in vitro. | in laboratory inoculation experiments, rosen rye seedlings were more susceptible, genesee wheat seedlings were less susceptible, and trail barley seedlings were not susceptible to claviceps purpurea. guttation fluids from these plants were used as media for the growth of germinating spores of c. purpurea. growth experiments consisted of spores which were germinated in thin agar films on microscope slides. germ tube growth was determined by counting the tubes that crossed the perimeter of a squar ... | 1962 | 17829704 |
| the small gtpase rac and the p21-activated kinase cla4 in claviceps purpurea: interaction and impact on polarity, development and pathogenicity. | claviceps purpurea, the ergot fungus, is a highly specialized pathogen of grasses; its colonization of host ovarian tissue requires an extended period of strictly polarized, oriented growth towards the vascular tissue. to understand this process, we study the role of signalling factors affecting polarity and differentiation. we showed that the small gtpase cdc42 is involved in polarity, sporulation and in planta growth in c. purpurea. here we present evidence that the gtpase rac has an even stro ... | 2008 | 18284596 |
| claviceps nigricans and claviceps grohii: their alkaloids and phylogenetic placement. | claviceps purpurea, c. grohii, c. zizaniae, c. cyperi, and c. nigricans are closely related ergot fungi and form a monophyletic clade inside the genus claviceps. analysis of alkaloid content in c. nigricans sclerotia using uplc detected ergocristine (1), ergosine (2), alpha-ergocryptine (3), and ergocristam (4). alkaloids 1, 3, and 4 were found in the sclerotia of c. grohii. the content of 4 in the mixture of alkaloids from c. nigricans and c. grohii (over 8% and over 20%, respectively) was unus ... | 2008 | 18461998 |
| mathematical modeling of growth and alkaloid production in claviceps purpurea batch fermentation. | an new systematic approach for describing claviceps purpurea growth and ergot alkaloid production during batch fermentation is presented. the model is based on microbial life, as the main characteristic for microbial development during fermentation process. the aging process of the microorganism is represented by life function, defined in microbial life space. the life space is defined as a measure in which the observer follows the development of a biosystem through physiological and morphologic ... | 1993 | 18609581 |
| the nadph oxidase cpnox1 is required for full pathogenicity of the ergot fungus claviceps purpurea. | the role of reactive oxygen species (ros) in interactions between phytopathogenic fungi and their hosts is well established. an oxidative burst mainly caused by superoxide formation by membrane-associated nadph oxidases is an essential element of plant defence reactions. apart from primary effects, ros play a major role as a second messenger in host response. recently, nadph oxidase (nox)-encoding genes have been identified in filamentous fungi. functional analyses have shown that these fungal e ... | 2008 | 18705873 |
| genetic variation for resistance to ergot (claviceps purpurea [fr.] tul.) among full-sib families of five populations of winter rye (secale cereale l.). | ergot (claviceps purpurea [fr.] tul.) is a serious disease of rye (secale cereale l.) and it adversely affects the quality of grain. the present investigation was undertaken to study genotypic variability among full-sib families (fsf) of five open-pollinated (op) winter rye populations of highly diverse origin, namely dankovskie selekcyine (poland), charkovskaja (ukraine), nem4 (russia), halo and carokurz, both from germany. about 50 fsf were developed at random in each population, and the fsf o ... | 2008 | 18797841 |
| the xylanolytic system of claviceps purpurea: cytological evidence for secretion of xylanases in infected rye tissue and molecular characterization of two xylanase genes. | abstract claviceps purpurea is a common phytopathogenic fungus that colonizes ovarian tissue of grasses. a concerted approach involving cytological and molecular techniques was initiated to investigate the role of the fungus' xylanolytic system in the interaction. using enzyme-gold and immuno-gold electron-microscopic techniques, the presence of arabinoxylans in cell walls of rye ovarian tissues (i.e., along the usual path of infection of c. purpurea) was confirmed; tissue-print and immunostaini ... | 1998 | 18944813 |
| secretion of a fungal extracellular catalase by claviceps purpurea during infection of rye: putative role in pathogenicity and suppression of host defense. | abstract hydrogen peroxide of the host origin accumulates in plant apoplasts in response to pathogen attack and probably functions directly in defense reactions or in signaling, according to a previous study. since claviceps purpurea produces compatible interactions with hundreds of host species, we hypothesized that the fungus might interfere with h(2)o(2)-mediated defense by means of secreted catalases. in axenic culture of c. purpurea, catalase activity accumulated in the medium and was inhib ... | 1998 | 18944879 |
| the major cu,zn sod of the phytopathogen claviceps purpurea is not essential for pathogenicity. | summary superoxide dismutase (sod) activities of the biotrophic pathogen claviceps purpurea, which causes the ergot disease on a wide range of host grasses, were examined in axenic and pathogenic cultures. almost all sod activity in axenic culture originated from a single cu,zn sod; a substantial part of this activity could be separated from lyophilized intact mycelia by gentle washing, indicating that this protein is at least partially secreted. the corresponding gene (cpsod1) was cloned and ch ... | 2002 | 20569304 |
| [antony's fire (gangrenous ergotism) and medieval iconography]. | ergotism was known as holy fire or st antony's fire in the middle ages, because of the burning sensations and limb gangrene it entailed. it was a frequent disorder, caused by eating rye flour contaminated by the fungus claviceps purpurea. the hospitable order of st antony was founded near vienne in france, and counted 400 establishments in europe by 1777. ergotism is the subject of an abundant iconography, including statues and paintings. woodcuts show the temptations of st antony, with strange ... | 2009 | 20669555 |
| molecular analysis of ∆6 desaturase and ∆6 elongase from conidiobolus obscurus in the biosynthesis of eicosatetraenoic acid, a ω3 fatty acid with nutraceutical potentials. | conidiobolus obscurus, an entomopathogenic fungus able to infect aphids, was previously reported to produce substantial amounts of very long chain polyunsaturated fatty acids (vlcpufas) that may mediate the insect infection. however, the genes involved in the biosynthesis of these vlcpufas from the order entomophthorales have yet to be identified. using degenerate reverse transcriptase-polymerase chain reaction and rapid amplification of the cdna end methods, we cloned a ∆6 desaturase cdna (cod6 ... | 2011 | 21210105 |
| online detection and quantification of ergot bodies in cereals using near infrared hyperspectral imaging. | the occurrence of ergot bodies (sclerotia of claviceps purpurea) in cereals presents a high toxicity risk for animals and humans due to the alkaloid content. to reduce this risk, the european commission fixed an ergot concentration limit of 0.1% in all feedstuffs containing unground cereals, and a limit of 0.05% in 'intervention' cereals destined for humans. this study sought to develop a procedure based on near infrared hyperspectral imaging and multivariate image analysis to detect and quantif ... | 2011 | 22059559 |
| alkaloid cluster gene ccsa of the ergot fungus claviceps purpurea encodes chanoclavine i synthase, a flavin adenine dinucleotide-containing oxidoreductase mediating the transformation of n-methyl-dimethylallyltryptophan to chanoclavine i. | ergot alkaloids are indole-derived secondary metabolites synthesized by the phytopathogenic ascomycete claviceps purpurea. in wild-type strains, they are exclusively produced in the sclerotium, a hibernation structure; for biotechnological applications, submerse production strains have been generated by mutagenesis. it was shown previously that the enzymes specific for alkaloid biosynthesis are encoded by a gene cluster of 68.5 kb. this ergot alkaloid cluster consists of 14 genes coregulated and ... | 2010 | 20118373 |
| the history of ergot of rye (claviceps purpurea) iii: 1940-80. | the period 1940-80 in the history of ergot was dominated by two investigators, arthur stoll and albert hofmann. there was great excitement when their group isolated from ergot preparations the powerful psychotropic agent lysergic acid diethylamide (lsd). it was thought that this substance would help to find the cause of schizophrenia and other psychotic disorders, but it would prove to be a great disappointment and hofmann would say later, in private, that he regretted having spent so much time ... | 2010 | 20503690 |
| the histidine kinase cphk2 has impact on spore germination, oxidative stress and fungicide resistance, and virulence of the ergot fungus claviceps purpurea. | summary histidine kinases are important mediators for adaptation of bacteria and plants to environmental signals. genome analyses of filamentous fungi have revealed the presence of a high number of potential hybrid histidine kinase (hk)-encoding genes; the role of most of these potential sensors is so far unclear, though some members of the class iii histidine kinases were shown to be involved in osmostress responses. here we present a functional analysis of cphk2, a histidine kinase-encoding ge ... | 2007 | 20507528 |
| the history of ergot of rye (claviceps purpurea) ii: 1900-1940. | ergot, in 1900, was a 'chemical mess'. henry wellcome, the pharmaceutical manufacturer, invited henry hallett dale, a physiologist, to join his research department and solve this problem. dale, in turn, recruited an outstanding group of scientists, including george barger, arthur ewins and harold dudley, who would make distinguished contributions not only to the chemistry of ergot but also to the identification of acetylcholine, histamine and tyramine and to studies on their physiological effect ... | 2009 | 20509463 |
| claviceps purpurea: molecular aspects of a unique pathogenic lifestyle. | summary claviceps purpurea is a ubiquitous pathogen of cereals and grasses, causing ergot disease, which results in substitution of grains by sclerotia. these overwintering structures contain ergot-alkaloids, which can cause severe intoxication in mammals. c. purpurea is an interesting model system for the study of host-pathogen interaction. it displays strict organ specificity, attacking exclusively young grass ovaries. it is optimally adapted to this special niche of infection, probably by mim ... | 2004 | 20565614 |