secondary fungal metabolites and their biological activities, v. investigations concerning the induction of the biosynthesis of toxic secondary metabolites in cultures of the basidiomycetes heterobasidion annosum, gloeophyllum abietinum or armillaria ostoyae, the biosynthesis of some of their toxic secondary metabolites is enhanced up to 400-fold when they grow in the presence of an antagonist. this stimulation is induced before any cell contact occurs. the "inducing signals" are not macromolecules, polypeptides or constituents of the cell membranes, but the same toxins which are synthesized already in monocultures in very low concentrations. after ...19948003259
detection of a chitinase-like protein in the roots of douglas-fir trees infected with armillaria ostoyae and phellinus weirii.protein was extracted from root bark of 11- and 25-year-old interior douglas-fir (pseudotsuga menziesii (mirb.) franco) trees that were naturally infected with armillaria ostoyae (romagnesi) herink. the proteins were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (sds-page). root bark tissue adjacent to infected areas had a significantly higher protein concentration than healthy tissue (p < 0.05), whereas the protein concentration of infected tissue was consistently lower ...200012651429
temporal and spatial dynamics of primary and secondary infection by armillaria ostoyae in a pinus pinaster plantation.abstract epidemiological investigations were performed in a 3-ha maritime pine (pinus pinaster) plantation established on a site heavily infested by armillaria ostoyae. geostatistics were used to examine the density and the distribution of the initial inoculum. disease dynamics were monitored for 17 years after planting. on the whole site, the cumulative mortality rate reached 35% over this period, plateauing at 12 years. disease progress curves differed according to the density of the initial i ...200418943534
gene cloning and tissue expression analysis of a pr-5 thaumatin-like protein in phellinus weirii-infected douglas-fir.abstract in western north america, douglas-fir (pseudotsuga menziesii) is the most economically important conifer species susceptible to laminated root rot caused by phellinus weirii. while attempting to internally sequence an endochitinase found to be up-regulated in p. weirii-infected douglas-fir roots, we obtained overlapping peptide fragments showing 28% similarity with a pr-5 thaumatin-like protein (tlp) designated pmtlp (pm for pseudotsuga menziesi). a rabbit polyclonal antibody was reared ...200418944459
phospholipid acylhydrolases trigger membrane degradation during fungal sporogenesis.armillaria ostoyae is a phytopathogen infecting coniferous trees. fruiting bodies of this basidiomycete contain high phospholipase a(1) (pla(1)) activity. in this paper, the role of phospholipid-deacylating activity, which was also detected in fruiting bodies of other basidiomycetes, in the fungal lipid metabolism is elucidated. for a. ostoyae the occurrence of pla(1) activity is shown to be restricted to the late reproductive phase, correlating with the release of mature spores. specific expres ...201121683150
evaluation of partial tef1, rpb2, and nlsu sequences for identification of isolates representing armillaria calvescens and armillaria gallica from northeastern north america.armillaria calvescens and armillaria gallica are two of the most closely-related species of armillaria in north america and have been difficult to distinguish from one another using morphological and molecular techniques. in an attempt to better distinguish these two species, partial sequences of the elongation factor-1 alpha (tef1), rna polymerase ii (rpb2), and nuclear large subunit (nlsu) genes were generated for 32 total isolates; 12 isolates each for a. calvescens and a. gallica, along with ...201121802054
genetic structure of an expanding armillaria root rot fungus (armillaria ostoyae) population in a managed pine forest in southwestern france.the landes de gascogne forest (southwestern france) is the largest maritime pine (pinus pinaster) plantation in europe. armillaria root disease (armillaria ostoyae) has been reported since the early 1920s in the coastal area (western sector), but its incidence over the last 20 years has increased in the eastern sector. we investigated the genetic structure of the a. ostoyae population in this forest, focusing particularly on geographical differentiation potentially indicative of disease expansio ...200818564091
mitochondrial dnas of the fungus armillaria ostoyae: restriction map and length variation.a restriction-enzyme-site map is presented for the 147-kb mtdna of north american armillaria ostoyae. the locations of five structural genes, atp6, atp8, coxi, coxiii, and cob, along with the location and orientation of the large and small ribosomal rna genes, were determined through southern hybridizations with cloned genes from other fungal mtdnas. based on this map, the variation in mtdna suggested geographic structure at two different levels. on a large geographic scale, 17 mtdna types from ...19948082207
secondary fungal metabolites and their biological activities, ii. occurrence of antibiotic compounds in cultures of armillaria ostoyae growing in the presence of an antagonistic fungus or host plant cells.we found that in the presence of host plant cells or some antagonistic fungi, the highly forest-pathogenic basidiomycete armillaria ostoyae is strongly stimulated to produce a series of toxic secondary metabolites which are capable of inhibiting the growth of the antagonist or of killing the plant cells still before cell contact. the chemical structures of the metabolites have been identified, of which two of them are new compounds. the time dependence and sites of synthesis in the mycelium have ...19921418682
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