The Experts below are selected from a list of 1959 Experts worldwide ranked by ideXlab platform
Paul Tudzynski - One of the best experts on this subject based on the ideXlab platform.
-
Brachypodium distachyon as alternative model host system for the ergot fungus Claviceps purpurea
Molecular plant pathology, 2017Co-Authors: Sabine Kind, Selma Schurack, Janine Hinsch, Paul TudzynskiAbstract:To investigate its susceptibility to ergot infection, we inoculated Brachypodium distachyon with Claviceps purpurea and compared the infection symptoms with those on rye (Secale cereale). We showed that, after inoculation of Brachypodium with Claviceps, the same disease symptoms occurred in comparable temporal and spatial patterns to those on rye. The infection rate of Claviceps on this host was reduced compared with rye, but the disease could be surveyed by fungal genomic DNA quantification. Mutants of Claviceps which were virulence attenuated on rye were also affected on Brachypodium. We were able to show that pathogenesis‐related gene expression changed in a typical manner for biotrophic pathogen attack. Our results indicated that the Claviceps–Brachypodium interaction was dependent on salicylic acid, cytokinin and auxin. We consider Brachypodium to be a suitable and useful alternative host; the increased sensitivity compared with rye will be valuable for the identification of infection mechanisms. Future progess in understanding the Claviceps–plant interaction will be facilitated by the use of a well‐characterized model host system.
-
Additional file 8: of Cross-talk of the biotrophic pathogen Claviceps purpurea and its host Secale cereale
2017Co-Authors: Birgitt Oeser, Paul Tudzynski, Sabine Kind, Selma Schurack, Thomas Schmutzer, Janine HinschAbstract:Predicted Claviceps purpurea effectors (XLSX 106 kb
-
ergot from witchcraft to biotechnology
Molecular Plant Pathology, 2009Co-Authors: Thomas Haarmann, Yvonne Rolke, Sabine Giesbert, Paul TudzynskiAbstract:SUMMARY The ergot diseases of grasses, caused by members of the genus Claviceps, have had a severe impact on human history and agriculture, causing devastating epidemics. However, ergot alkaloids, the toxic components of Claviceps sclerotia, have been used intensively (and misused) as pharmaceutical drugs, and efficient biotechnological processes have been developed for their in vitro production. Molecular genetics has provided detailed insight into the genetic basis of ergot alkaloid biosynthesis and opened up perspectives for the design of new alkaloids and the improvement of production strains; it has also revealed the refined infection strategy of this biotrophic pathogen, opening up the way for better control. Nevertheless, Claviceps remains an important pathogen worldwide, and a source for potential new drugs for central nervous system diseases.
-
comparison of ergot alkaloid biosynthesis gene clusters in Claviceps species indicates loss of late pathway steps in evolution of c fusiformis
Applied and Environmental Microbiology, 2007Co-Authors: Nicole Lorenz, Caroline Machado, Christopher L Schardl, Ella V Wilson, Paul TudzynskiAbstract: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). We analyzed the corresponding C. fusiformis EAS cluster to investigate the evolutionary basis for chemotypic differences between the Claviceps species. Other than three peptide synthetase genes (lpsC and the tandem paralogues lpsA1 and lpsA2), homologues of all C. purpurea EAS genes were identified in C. fusiformis, including homologues of lpsB and cloA, which in C. purpurea encode enzymes for steps after clavine synthesis. Rearrangement of the cluster was evident around lpsB, which is truncated in C. fusiformis. This and several frameshift mutations render CflpsB a pseudogene (CflpsBΨ). No obvious inactivating mutation was identified in CfcloA. All C. fusiformis EAS genes, including CflpsBΨ and CfcloA, were expressed in culture. Cross-complementation analyses demonstrated that CfcloA and CflpsBΨ were expressed in C. purpurea but did not encode functional enzymes. In contrast, CpcloA catalyzed lysergic acid biosynthesis in C. fusiformis, indicating that C. fusiformis terminates its EAS pathway at elymoclavine because the cloA gene product is inactive. We propose that the C. fusiformis EAS cluster evolved from a more complete cluster by loss of some lps genes and by rearrangements and mutations inactivating lpsB and cloA.
-
comparison of ergot alkaloid biosynthesis gene clusters in Claviceps species indicates loss of late pathway steps in evolution of c fusiformis
Applied and Environmental Microbiology, 2007Co-Authors: Nicole Lorenz, Caroline Machado, Christopher L Schardl, Ella V Wilson, Paul TudzynskiAbstract: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). We analyzed the corresponding C. fusiformis EAS cluster to investigate the evolutionary basis for chemotypic differences between the Claviceps species. Other than three peptide synthetase genes (lpsC and the tandem paralogues lpsA1 and lpsA2), homologues of all C. purpurea EAS genes were identified in C. fusiformis, including homologues of lpsB and cloA, which in C. purpurea encode enzymes for steps after clavine synthesis. Rearrangement of the cluster was evident around lpsB, which is truncated in C. fusiformis. This and several frameshift mutations render CflpsB a pseudogene (CflpsBΨ). No obvious inactivating mutation was identified in CfcloA. All C. fusiformis EAS genes, including CflpsBΨ and CfcloA, were expressed in culture. Cross-complementation analyses demonstrated that CfcloA and CflpsBΨ were expressed in C. purpurea but did not encode functional enzymes. In contrast, CpcloA catalyzed lysergic acid biosynthesis in C. fusiformis, indicating that C. fusiformis terminates its EAS pathway at elymoclavine because the cloA gene product is inactive. We propose that the C. fusiformis EAS cluster evolved from a more complete cluster by loss of some lps genes and by rearrangements and mutations inactivating lpsB and cloA.
Christopher L Schardl - One of the best experts on this subject based on the ideXlab platform.
-
comparison of ergot alkaloid biosynthesis gene clusters in Claviceps species indicates loss of late pathway steps in evolution of c fusiformis
Applied and Environmental Microbiology, 2007Co-Authors: Nicole Lorenz, Caroline Machado, Christopher L Schardl, Ella V Wilson, Paul TudzynskiAbstract: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). We analyzed the corresponding C. fusiformis EAS cluster to investigate the evolutionary basis for chemotypic differences between the Claviceps species. Other than three peptide synthetase genes (lpsC and the tandem paralogues lpsA1 and lpsA2), homologues of all C. purpurea EAS genes were identified in C. fusiformis, including homologues of lpsB and cloA, which in C. purpurea encode enzymes for steps after clavine synthesis. Rearrangement of the cluster was evident around lpsB, which is truncated in C. fusiformis. This and several frameshift mutations render CflpsB a pseudogene (CflpsBΨ). No obvious inactivating mutation was identified in CfcloA. All C. fusiformis EAS genes, including CflpsBΨ and CfcloA, were expressed in culture. Cross-complementation analyses demonstrated that CfcloA and CflpsBΨ were expressed in C. purpurea but did not encode functional enzymes. In contrast, CpcloA catalyzed lysergic acid biosynthesis in C. fusiformis, indicating that C. fusiformis terminates its EAS pathway at elymoclavine because the cloA gene product is inactive. We propose that the C. fusiformis EAS cluster evolved from a more complete cluster by loss of some lps genes and by rearrangements and mutations inactivating lpsB and cloA.
-
comparison of ergot alkaloid biosynthesis gene clusters in Claviceps species indicates loss of late pathway steps in evolution of c fusiformis
Applied and Environmental Microbiology, 2007Co-Authors: Nicole Lorenz, Caroline Machado, Christopher L Schardl, Ella V Wilson, Paul TudzynskiAbstract: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). We analyzed the corresponding C. fusiformis EAS cluster to investigate the evolutionary basis for chemotypic differences between the Claviceps species. Other than three peptide synthetase genes (lpsC and the tandem paralogues lpsA1 and lpsA2), homologues of all C. purpurea EAS genes were identified in C. fusiformis, including homologues of lpsB and cloA, which in C. purpurea encode enzymes for steps after clavine synthesis. Rearrangement of the cluster was evident around lpsB, which is truncated in C. fusiformis. This and several frameshift mutations render CflpsB a pseudogene (CflpsBΨ). No obvious inactivating mutation was identified in CfcloA. All C. fusiformis EAS genes, including CflpsBΨ and CfcloA, were expressed in culture. Cross-complementation analyses demonstrated that CfcloA and CflpsBΨ were expressed in C. purpurea but did not encode functional enzymes. In contrast, CpcloA catalyzed lysergic acid biosynthesis in C. fusiformis, indicating that C. fusiformis terminates its EAS pathway at elymoclavine because the cloA gene product is inactive. We propose that the C. fusiformis EAS cluster evolved from a more complete cluster by loss of some lps genes and by rearrangements and mutations inactivating lpsB and cloA.
-
Loline and Ergot Alkaloids in Grass Endophytes
2006Co-Authors: Christopher L Schardl, Jimmy D. Blankenship, Martin J. Spiering, Caroline MachadoAbstract:Many of the common grasses in woodlands and meadows, pastures, lawns, roadsides, and sport fields are aided in their survival by inconspicuous fungal symbionts, termed endophytes. The Epichloe spp. and Neotyphodium spp. (asexual counterparts of Epichloe spp.) are grass endophytes belonging to the fungal family Clavicipitaceae (phylum Ascomycota, order Hypocreales). The family Clavicipitaceae is best known for the ergot fungi, Claviceps spp., which do not engage in such benign symbioses as do their endophytic cousins. Instead, Claviceps spp. infect florets on developing seed heads, where they replace ovaries with hard, dormant sclerotia. These ‘‘ergots’’ often contain high levels of alkaloids with neurotropic activities in vertebrates and insects. The term ergot alkaloids (also known as ergoline alkaloids, ergoalkaloids, or ergotoxins) refers to one class of such metabolites, especially those from Claviceps purpurea. Sclerotia of C. purpurea contain approx. 1% (dry mass) of the ergopeptines, ergotamine, and ergocristine [1]. In addition to the ergot alkaloid class, however, some Claviceps spp. also produce indole-diterpene tremorgens that are built from similar precursors but are structurally and pharmacologically quite different from ergot alkaloids. The tremorgens, which are also neurotropic and active against vertebrates
-
The ergot alkaloid gene cluster in Claviceps purpurea : Extension of the cluster sequence and intra species evolution
Phytochemistry, 2005Co-Authors: Thomas Haarmann, Yvonne Lübbe, Telmo Correia, Caroline Machado, Christopher L Schardl, Daniel G Panaccione, Paul TudzynskiAbstract:Abstract The genomic region of Claviceps purpurea strain P1 containing the ergot alkaloid gene cluster [Tudzynski, P., Holter, K., Correia, T., Arntz, C., Grammel, N., Keller, U., 1999. Evidence for an ergot alkaloid gene cluster in Claviceps purpurea. Mol. Gen. Genet. 261, 133–141] was explored by chromosome walking, and additional genes probably involved in the ergot alkaloid biosynthesis have been identified. The putative cluster sequence (extending over 68.5 kb) contains 4 different nonribosomal peptide synthetase (NRPS) genes and several putative oxidases. Northern analysis showed that most of the genes were co-regulated (repressed by high phosphate), and identified probable flanking genes by lack of co-regulation. Comparison of the cluster sequences of strain P1, an ergotamine producer, with that of strain ECC93, an ergocristine producer, showed high conservation of most of the cluster genes, but significant variation in the NRPS modules, strongly suggesting that evolution of these chemical races of C. purpurea is determined by evolution of NRPS module specificity.
-
the determinant step in ergot alkaloid biosynthesis by an endophyte of perennial ryegrass
Fungal Genetics and Biology, 2004Co-Authors: Jinghong Wang, Caroline Machado, Daniel G Panaccione, Hueifung Tsai, Christopher L SchardlAbstract:Many cool-season grasses harbor fungal endophytes in the genus Neotyphodium, which enhance host fitness, but some also produce metabolites--such as ergovaline--believed to cause livestock toxicoses. In Claviceps species the first step in ergot alkaloid biosynthesis is thought to be dimethylallyltryptophan (DMAT) synthase, encoded by dmaW, previously cloned from Claviceps fusiformis. Here we report the cloning and characterization of dmaW from Neotyphodium sp. isolate Lp1, an endophyte of perennial ryegrass (Lolium perenne). The gene was then disrupted, and the mutant failed to produce any detectable ergovaline or simpler ergot and clavine alkaloids. The disruption was complemented with the C. fusiformis gene, which restored ergovaline production. Thus, the biosynthetic role of DMAT synthase was confirmed, and a mutant was generated for future studies of the ecological and agricultural importance of ergot alkaloids in endophytes of grasses.
Caroline Machado - One of the best experts on this subject based on the ideXlab platform.
-
comparison of ergot alkaloid biosynthesis gene clusters in Claviceps species indicates loss of late pathway steps in evolution of c fusiformis
Applied and Environmental Microbiology, 2007Co-Authors: Nicole Lorenz, Caroline Machado, Christopher L Schardl, Ella V Wilson, Paul TudzynskiAbstract: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). We analyzed the corresponding C. fusiformis EAS cluster to investigate the evolutionary basis for chemotypic differences between the Claviceps species. Other than three peptide synthetase genes (lpsC and the tandem paralogues lpsA1 and lpsA2), homologues of all C. purpurea EAS genes were identified in C. fusiformis, including homologues of lpsB and cloA, which in C. purpurea encode enzymes for steps after clavine synthesis. Rearrangement of the cluster was evident around lpsB, which is truncated in C. fusiformis. This and several frameshift mutations render CflpsB a pseudogene (CflpsBΨ). No obvious inactivating mutation was identified in CfcloA. All C. fusiformis EAS genes, including CflpsBΨ and CfcloA, were expressed in culture. Cross-complementation analyses demonstrated that CfcloA and CflpsBΨ were expressed in C. purpurea but did not encode functional enzymes. In contrast, CpcloA catalyzed lysergic acid biosynthesis in C. fusiformis, indicating that C. fusiformis terminates its EAS pathway at elymoclavine because the cloA gene product is inactive. We propose that the C. fusiformis EAS cluster evolved from a more complete cluster by loss of some lps genes and by rearrangements and mutations inactivating lpsB and cloA.
-
comparison of ergot alkaloid biosynthesis gene clusters in Claviceps species indicates loss of late pathway steps in evolution of c fusiformis
Applied and Environmental Microbiology, 2007Co-Authors: Nicole Lorenz, Caroline Machado, Christopher L Schardl, Ella V Wilson, Paul TudzynskiAbstract: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). We analyzed the corresponding C. fusiformis EAS cluster to investigate the evolutionary basis for chemotypic differences between the Claviceps species. Other than three peptide synthetase genes (lpsC and the tandem paralogues lpsA1 and lpsA2), homologues of all C. purpurea EAS genes were identified in C. fusiformis, including homologues of lpsB and cloA, which in C. purpurea encode enzymes for steps after clavine synthesis. Rearrangement of the cluster was evident around lpsB, which is truncated in C. fusiformis. This and several frameshift mutations render CflpsB a pseudogene (CflpsBΨ). No obvious inactivating mutation was identified in CfcloA. All C. fusiformis EAS genes, including CflpsBΨ and CfcloA, were expressed in culture. Cross-complementation analyses demonstrated that CfcloA and CflpsBΨ were expressed in C. purpurea but did not encode functional enzymes. In contrast, CpcloA catalyzed lysergic acid biosynthesis in C. fusiformis, indicating that C. fusiformis terminates its EAS pathway at elymoclavine because the cloA gene product is inactive. We propose that the C. fusiformis EAS cluster evolved from a more complete cluster by loss of some lps genes and by rearrangements and mutations inactivating lpsB and cloA.
-
Loline and Ergot Alkaloids in Grass Endophytes
2006Co-Authors: Christopher L Schardl, Jimmy D. Blankenship, Martin J. Spiering, Caroline MachadoAbstract:Many of the common grasses in woodlands and meadows, pastures, lawns, roadsides, and sport fields are aided in their survival by inconspicuous fungal symbionts, termed endophytes. The Epichloe spp. and Neotyphodium spp. (asexual counterparts of Epichloe spp.) are grass endophytes belonging to the fungal family Clavicipitaceae (phylum Ascomycota, order Hypocreales). The family Clavicipitaceae is best known for the ergot fungi, Claviceps spp., which do not engage in such benign symbioses as do their endophytic cousins. Instead, Claviceps spp. infect florets on developing seed heads, where they replace ovaries with hard, dormant sclerotia. These ‘‘ergots’’ often contain high levels of alkaloids with neurotropic activities in vertebrates and insects. The term ergot alkaloids (also known as ergoline alkaloids, ergoalkaloids, or ergotoxins) refers to one class of such metabolites, especially those from Claviceps purpurea. Sclerotia of C. purpurea contain approx. 1% (dry mass) of the ergopeptines, ergotamine, and ergocristine [1]. In addition to the ergot alkaloid class, however, some Claviceps spp. also produce indole-diterpene tremorgens that are built from similar precursors but are structurally and pharmacologically quite different from ergot alkaloids. The tremorgens, which are also neurotropic and active against vertebrates
-
The ergot alkaloid gene cluster in Claviceps purpurea : Extension of the cluster sequence and intra species evolution
Phytochemistry, 2005Co-Authors: Thomas Haarmann, Yvonne Lübbe, Telmo Correia, Caroline Machado, Christopher L Schardl, Daniel G Panaccione, Paul TudzynskiAbstract:Abstract The genomic region of Claviceps purpurea strain P1 containing the ergot alkaloid gene cluster [Tudzynski, P., Holter, K., Correia, T., Arntz, C., Grammel, N., Keller, U., 1999. Evidence for an ergot alkaloid gene cluster in Claviceps purpurea. Mol. Gen. Genet. 261, 133–141] was explored by chromosome walking, and additional genes probably involved in the ergot alkaloid biosynthesis have been identified. The putative cluster sequence (extending over 68.5 kb) contains 4 different nonribosomal peptide synthetase (NRPS) genes and several putative oxidases. Northern analysis showed that most of the genes were co-regulated (repressed by high phosphate), and identified probable flanking genes by lack of co-regulation. Comparison of the cluster sequences of strain P1, an ergotamine producer, with that of strain ECC93, an ergocristine producer, showed high conservation of most of the cluster genes, but significant variation in the NRPS modules, strongly suggesting that evolution of these chemical races of C. purpurea is determined by evolution of NRPS module specificity.
-
the determinant step in ergot alkaloid biosynthesis by an endophyte of perennial ryegrass
Fungal Genetics and Biology, 2004Co-Authors: Jinghong Wang, Caroline Machado, Daniel G Panaccione, Hueifung Tsai, Christopher L SchardlAbstract:Many cool-season grasses harbor fungal endophytes in the genus Neotyphodium, which enhance host fitness, but some also produce metabolites--such as ergovaline--believed to cause livestock toxicoses. In Claviceps species the first step in ergot alkaloid biosynthesis is thought to be dimethylallyltryptophan (DMAT) synthase, encoded by dmaW, previously cloned from Claviceps fusiformis. Here we report the cloning and characterization of dmaW from Neotyphodium sp. isolate Lp1, an endophyte of perennial ryegrass (Lolium perenne). The gene was then disrupted, and the mutant failed to produce any detectable ergovaline or simpler ergot and clavine alkaloids. The disruption was complemented with the C. fusiformis gene, which restored ergovaline production. Thus, the biosynthetic role of DMAT synthase was confirmed, and a mutant was generated for future studies of the ecological and agricultural importance of ergot alkaloids in endophytes of grasses.
Sylvie Pažoutova - One of the best experts on this subject based on the ideXlab platform.
-
evolutionary history of ergot with a new infrageneric classification hypocreales clavicipitaceae Claviceps
Molecular Phylogenetics and Evolution, 2018Co-Authors: Kamila Pichova, Sylvie Pažoutova, Miroslav Flieger, Milada Chudickova, Eva Stodůlkova, Martin Kostovcik, Petr Novak, Elna Van Der Linde, Miroslav KolaříkAbstract:Abstract The ergot, genus Claviceps, comprises approximately 60 species of specialised ovarial grass parasites famous for the production of food toxins and pharmaceutics. Although the ergot has been known for centuries, its evolution have not been resolved yet. Our approach combining multilocus phylogeny, molecular dating and the study of ecological, morphological and metabolic features shows that Claviceps originated in South America in the Palaeocene on a common ancestor of BEP (subfamilies Bambusoideae, Ehrhartoideae, Pooideae) and PACMAD (subfamilies Panicoideae, Aristidoideae, Chloridoideae, Micrairoideae, Arundinoideae, Danthonioideae) grasses. Four clades described here as sections diverged during the Paleocene and Eocene. Since Claviceps are parasitic fungi with a close relationship with their host plants, their evolution is influenced by interactions with the new hosts, either by the spread to a new continent or the radiation of the host plants. Three of the sections possess very narrow host ranges and biogeographical distributions and have relatively low toxicity. On the contrary, the section Claviceps, comprising the rye ergot, C. purpurea, is unique in all aspects. Fungi in this section of North American origin have spread all over the world and infect grasses in all subfamilies as well as sedges, and it is the only section synthesising toxic ergopeptines and secalonic acids. The evolutionary success of the Claviceps section members can be explained by high toxin presence, serving as feeding deterrents and playing a role in their protective mutualism with host plants. Closely related taxa NeoClaviceps monostipa and Cepsiclava phalaridis were combined into the genus Aciculosporium.
-
ergot species of the Claviceps purpurea group from south africa
Fungal Biology, 2016Co-Authors: Elna Van Der Linde, Sylvie Pažoutova, Miroslav Flieger, Kamila Pesicova, Eva Stodůlkova, Miroslav KolaříkAbstract:Results of a survey and study of the Claviceps purpurea group of species in South Africa are being presented and five new species are described. Morphological descriptions are based on the anamorphs and four nuclear genetic loci. Claviceps fimbristylidis sp. nov. on Fimbristylis complanata was discovered wide-spread across five provinces of the country associated with water and represents the fourth Claviceps species recorded from the Cyperaceae. Claviceps monticola sp. nov. is described from Brachypodium flexum growing in mountain forests in Mpumalanga Province, as well as the northern Drakensberg southwards into the Eastern Cape Province. Claviceps pazoutovae sp. nov. is recorded from Stipa dregeana var. dregeana and Ehrharta erecta var. erecta, also associated with these mountain ranges. Claviceps macroura sp. nov. is recorded from Cenchrus macrourus from the Eastern Cape and Claviceps capensis sp. nov. from Ehrharta villosa var. villosa is recorded from the Western Cape Province. Claviceps cyperi, only recorded from South Africa is included in the study. Ergot alkaloid profiles of all species are provided and showed similarity to C. purpurea. Only C. cyperi and in lesser degree C. capensis, C. macroura, and C. pazoutovae produced ergot alkaloids in clinically significant amounts. Several reported species infect invasive grass species, native to South Africa, and thus represent potentially invasive species.
-
delimitation of cryptic species inside Claviceps purpurea
Fungal Biology, 2015Co-Authors: Sylvie Pažoutova, Kamila Pesicova, Milada Chudickova, Petr Srůtka, Miroslav KolaříkAbstract:Claviceps purpurea is an ovarian parasite infecting grasses (Poaceae) including cereals and forage plants. This fungus produces toxic alkaloids and consumption of contaminated grains can cause ergotism in humans and other mammals. Recent molecular genetics studies have indicated that it included three cryptic species (G1, G2, G3). In this study, reproductive isolation amongst these groups and among material from Phragmites and Molinia was tested using gene flow statistics for five polymorphic loci, and to support these data, phylogenetic affiliations based on gene trees and a multigene phylogeny were used. The four recognized species are characterized based on morphology and host spectrum and formal taxonomic names are proposed. Claviceps purpurea sensu stricto (G1 group) represents a typical rye ergot, but infects various other grasses. Typical hosts of Claviceps humidiphila (new name for G2 species), like Phalaris arundinacea, belong to grasses preferring humid locations. Claviceps spartinae (G3) is specific to chloridoid grasses from salt barches. The material from Phragmites and Molinia can be authenticated with the species Claviceps microcephala for which the new name Claviceps arundinis is proposed here. The divergence time between species was estimated and the tools for species identification are discussed.
-
Pleomorphic conidiation in Claviceps
Mycological Research, 2004Co-Authors: Sylvie Pažoutova, Miroslav Kolařík, Renata KolínskáAbstract:Types of asexual sporulation in 17 Claviceps species and the closely related Corallocytostroma ornicopreoides were revised in relation to the phylogeny of clavicipitaceous fungi. We observed: (1) enteroblastic conidiation from branched phialidic conidiophores typical of the genus (anamorph Sphacelia ) in all species including Corallocytostroma; (2) widespread and often sequential formation of terminal holoblastic secondary conidia on tapering hyphae arising from sphacelial macroconidia; and (3) in addition to sphacelial conidiation, sympodial holoblastic conidiation of the Ephelis -type in cultures of C. zizaniae and in both the culture and sphacelial tissue of C. citrina. Secondary conidiation was not found in C. purpurea, C. citrina and C. sorghicola. During sphacelial fructification, most species produced macroconidia and microconidia. Only macroconidia formed in planta underwent secondary conidiation whereas microconidia did not germinate at all. In C. phalaridis the formation of holoblastic 2–3 celled appendaged conidia was observed, similar to that of Aciculosporium and NeoClaviceps. In dendrograms based on ITS1–5.8S rDNA-ITS2 sequences, genera and species with appendaged conidia grouped on a highly supported clade with ancestral Corallocytostroma. The clade was placed inside a group of tropical species of Claviceps without any relationship to Balansiae.
-
the phylogeny and evolution of the genus Claviceps
Fungal Biology, 2001Co-Authors: Sylvie PažoutovaAbstract:Phylogenetic trees of 16 Claviceps species were constructed based on alignments of 5.8S rDNA and the adjacent ITS1 and ITS2 spacers. Two highly supported clades were found: (1) C. paspali, C. zizaniae, C. grohii, C. sulcata, C. fusiformis , and C. purpurea ; and (2) C. citrina, C. phalaridis , two unidentified Claviceps spp. (isolates PM and SG), C. sorghicola, C. gigantea, C. sorghi, C. africana, C. viridis , and C. pusilla. No relationship was found between the species placement and its morphological markers. The probe from C. purpurea gene cpd1 for dimethylallyl tryptophan synthase, the first enzyme of alkaloid biosynthesis, was hybridized to Pst 1 digested genomes of the above species under non-stringent conditions. Hybridizing DNA was present in all species of clade 1, although the signal of the C. paspali gene was weaker. In clade 2, only C. africana, C. gigantea , and C. pusilla gave weak positive signals. Colorimetric detection found small amounts of alkaloids in cultures of Claviceps sp. SG and PM but despite that, no cpd1 hybridizing bands were found. The occurrence of two major clades of Claviceps and their biogeography suggests, that the genus originates from South America and that the evolution of its species was influenced by comigration with their hosts and with the global climatic changes that influenced spreading of grass subfamilies.
Miroslav Kolařík - One of the best experts on this subject based on the ideXlab platform.
-
evolutionary history of ergot with a new infrageneric classification hypocreales clavicipitaceae Claviceps
Molecular Phylogenetics and Evolution, 2018Co-Authors: Kamila Pichova, Sylvie Pažoutova, Miroslav Flieger, Milada Chudickova, Eva Stodůlkova, Martin Kostovcik, Petr Novak, Elna Van Der Linde, Miroslav KolaříkAbstract:Abstract The ergot, genus Claviceps, comprises approximately 60 species of specialised ovarial grass parasites famous for the production of food toxins and pharmaceutics. Although the ergot has been known for centuries, its evolution have not been resolved yet. Our approach combining multilocus phylogeny, molecular dating and the study of ecological, morphological and metabolic features shows that Claviceps originated in South America in the Palaeocene on a common ancestor of BEP (subfamilies Bambusoideae, Ehrhartoideae, Pooideae) and PACMAD (subfamilies Panicoideae, Aristidoideae, Chloridoideae, Micrairoideae, Arundinoideae, Danthonioideae) grasses. Four clades described here as sections diverged during the Paleocene and Eocene. Since Claviceps are parasitic fungi with a close relationship with their host plants, their evolution is influenced by interactions with the new hosts, either by the spread to a new continent or the radiation of the host plants. Three of the sections possess very narrow host ranges and biogeographical distributions and have relatively low toxicity. On the contrary, the section Claviceps, comprising the rye ergot, C. purpurea, is unique in all aspects. Fungi in this section of North American origin have spread all over the world and infect grasses in all subfamilies as well as sedges, and it is the only section synthesising toxic ergopeptines and secalonic acids. The evolutionary success of the Claviceps section members can be explained by high toxin presence, serving as feeding deterrents and playing a role in their protective mutualism with host plants. Closely related taxa NeoClaviceps monostipa and Cepsiclava phalaridis were combined into the genus Aciculosporium.
-
ergot species of the Claviceps purpurea group from south africa
Fungal Biology, 2016Co-Authors: Elna Van Der Linde, Sylvie Pažoutova, Miroslav Flieger, Kamila Pesicova, Eva Stodůlkova, Miroslav KolaříkAbstract:Results of a survey and study of the Claviceps purpurea group of species in South Africa are being presented and five new species are described. Morphological descriptions are based on the anamorphs and four nuclear genetic loci. Claviceps fimbristylidis sp. nov. on Fimbristylis complanata was discovered wide-spread across five provinces of the country associated with water and represents the fourth Claviceps species recorded from the Cyperaceae. Claviceps monticola sp. nov. is described from Brachypodium flexum growing in mountain forests in Mpumalanga Province, as well as the northern Drakensberg southwards into the Eastern Cape Province. Claviceps pazoutovae sp. nov. is recorded from Stipa dregeana var. dregeana and Ehrharta erecta var. erecta, also associated with these mountain ranges. Claviceps macroura sp. nov. is recorded from Cenchrus macrourus from the Eastern Cape and Claviceps capensis sp. nov. from Ehrharta villosa var. villosa is recorded from the Western Cape Province. Claviceps cyperi, only recorded from South Africa is included in the study. Ergot alkaloid profiles of all species are provided and showed similarity to C. purpurea. Only C. cyperi and in lesser degree C. capensis, C. macroura, and C. pazoutovae produced ergot alkaloids in clinically significant amounts. Several reported species infect invasive grass species, native to South Africa, and thus represent potentially invasive species.
-
delimitation of cryptic species inside Claviceps purpurea
Fungal Biology, 2015Co-Authors: Sylvie Pažoutova, Kamila Pesicova, Milada Chudickova, Petr Srůtka, Miroslav KolaříkAbstract:Claviceps purpurea is an ovarian parasite infecting grasses (Poaceae) including cereals and forage plants. This fungus produces toxic alkaloids and consumption of contaminated grains can cause ergotism in humans and other mammals. Recent molecular genetics studies have indicated that it included three cryptic species (G1, G2, G3). In this study, reproductive isolation amongst these groups and among material from Phragmites and Molinia was tested using gene flow statistics for five polymorphic loci, and to support these data, phylogenetic affiliations based on gene trees and a multigene phylogeny were used. The four recognized species are characterized based on morphology and host spectrum and formal taxonomic names are proposed. Claviceps purpurea sensu stricto (G1 group) represents a typical rye ergot, but infects various other grasses. Typical hosts of Claviceps humidiphila (new name for G2 species), like Phalaris arundinacea, belong to grasses preferring humid locations. Claviceps spartinae (G3) is specific to chloridoid grasses from salt barches. The material from Phragmites and Molinia can be authenticated with the species Claviceps microcephala for which the new name Claviceps arundinis is proposed here. The divergence time between species was estimated and the tools for species identification are discussed.
-
Pleomorphic conidiation in Claviceps
Mycological Research, 2004Co-Authors: Sylvie Pažoutova, Miroslav Kolařík, Renata KolínskáAbstract:Types of asexual sporulation in 17 Claviceps species and the closely related Corallocytostroma ornicopreoides were revised in relation to the phylogeny of clavicipitaceous fungi. We observed: (1) enteroblastic conidiation from branched phialidic conidiophores typical of the genus (anamorph Sphacelia ) in all species including Corallocytostroma; (2) widespread and often sequential formation of terminal holoblastic secondary conidia on tapering hyphae arising from sphacelial macroconidia; and (3) in addition to sphacelial conidiation, sympodial holoblastic conidiation of the Ephelis -type in cultures of C. zizaniae and in both the culture and sphacelial tissue of C. citrina. Secondary conidiation was not found in C. purpurea, C. citrina and C. sorghicola. During sphacelial fructification, most species produced macroconidia and microconidia. Only macroconidia formed in planta underwent secondary conidiation whereas microconidia did not germinate at all. In C. phalaridis the formation of holoblastic 2–3 celled appendaged conidia was observed, similar to that of Aciculosporium and NeoClaviceps. In dendrograms based on ITS1–5.8S rDNA-ITS2 sequences, genera and species with appendaged conidia grouped on a highly supported clade with ancestral Corallocytostroma. The clade was placed inside a group of tropical species of Claviceps without any relationship to Balansiae.