Claviceps species

For a description of a wild American Claviceps species see Mycologia 66,978(1974). 

Tooley, P. W., Goley, E. D., Carras, M. M., Frederick, R. D., and Weber, E. L. (2001). Characterization of Claviceps species pathogenic on sorghum by sequence analysis of the /1-tubulin gene intron 3 region and EF-la gene intron 4. Mycologia 93, 541-551. 

From the culture filtrates of two different Claviceps species, strain SD 58 and C. fusiformis, strain 139/2/lG, a new amino acid was isolated, named clavicipitic acid, (C16H18N202 mp 262°). 

Ergot Alkaloids.—The enzyme which catalyses the first step in ergot alkaloid biosynthesis, namely the conversion of tryptophan into dimethylallyltryptophan (126),110 has been isolated from a Claviceps species and characterized.111 The biosynthesis of clavicipitic acid (127) may be a major alternative to the synthesis of other ergot metabolites, and further results in a study112 of an enzyme from C. purpurea which catalyses the formation of clavicipitic acid (127) from (126) have been published.113... 

Ergot Alkaloid Extraction from Claviceps Species... 

Clavicipitic acid (29) is another compound from an interrupted biogenesis which was obtained from a Claviceps species by feedingethionine as antagonist. The structure follows more or less from the obvious spectral measurements and from feeding experiments which showed that mevalonate and tryptophan, in which the hydrogen a to carbonyl was retained, were both incorporated. 

Resting structures are produced by some species. The ergot sclerotium produced by Claviceps species is the best-known example these dark structures develop in place of an ovary in a grass inflorescence (Stewart, 1957) they germinate to produce a sexual stroma, some first requiring a dormant period. 

Langdon RFN. The origin and differentiation of Claviceps species. Univ Qld Pap 3 61 -68, 1954. 

Moller (1901) recognized unusual patterns of ascospore germination, such as repeated conidia formation, and disarticulation of ascospores. Observations on ascospore germination have not been included in the technical description of most Claviceps species, although such observation may have some value in characterizing and differentiating some species. 

Claviceps species have evolved mechanisms for survival and timing of ascospore production in diverse habitats. In temperate climates, species such as C. purpurea,... 

Brady LR. Phylogpnetic distribution of parasitism by Claviceps species. Lloydia J Nat Prod 25 1-36, 1962. 

Samuelson RJ, Gjerstad G. Intermediary metabolism of ergot XIII, feather ergot, a new, promising Claviceps species. Medd Nor Farm Selsk 28 229-237, 1966. 

Figure7 Neighbor joining phylogeny based on a partial dmaW alignment of DNA sequences from ergot alkaloid producing Neotyphodium, Balansia, and Claviceps species.

In temperate regions of both hemispheres, C. purpurea prevails. Due to seed transfer by settlers, it is not possible to find out if the original distribution was in the Northern Hemisphere only. There is no other grass-colonizing Claviceps species. Related species are from sedges and rushes only, or in the case of C. zizaniae, an oryzoid host. 

Langdon (1954) placed the origin of the genus Claviceps in the South America region formerly known as Gondwana. The first Claviceps species probably arose on the predecessors of panicoid grasses in the warm and humid climate of... 

Gondwana in the Upper Cretaceous. Our tree supports this hypothesis, as the ancestral species are predominantly from South and Central America. Moreover, the radiation center of panicoid grasses is in that region, and Claviceps species with primitive undifferentiated sclerotia were recorded in that area. Preservation of these lineages was probably facilitated by the isolation of South America from the end of the Cretaceous until the end of the Tertiary (Stebbins, 1981). 

The taxonomic criteria used to deliminate Claviceps species are the color, size, and shape of sclerotia the color of ascostromata (stipe and capitulum) the presence or absence of loose hyphae on the stroma the size and shape of perithecia, asci, and ascospores (Langdon, 1942). From these markers, only sclerotium formation and type of asexual fructification bear phylogenetical importance. 

The more recent records of Claviceps species with intermediary characteristics are C. phalaridis, related Neoclaviceps monostipa, and according to yet unpublished observations, C. citrina. 

---