Enzymatic Formation of Rufoschweinitzin, a Binaphthalene from the Basidiomycete Cortinarius rufoolivaceus.

Dimeric polyketides are widespread fungal secondary metabolites. They occur in both ascomycetes and basidiomycetes and, therefore, across fungal phyla. Here we report the isolation of a new binaphthalene, named rufoschweinitzin, from the basidiomycete Cortinarius rufoolivaceus. Rufoschweinitzin consists of two symmetrically 4,4'-coupled torachrysone-8-O-methyl ether moieties. Furthermore, we have identified a binaphthalene biosynthetic gene cluster in an unrelated fungus, the ascomycete Xylaria schweinitzii. Heterologous expression of the encoded cytochrome P450 enzyme verified its coupling activity: dimerization of torachrysone-8-O-methyl ether led to the formation of rufoschweinitzin alongside a hitherto unknown regioisomer, now named alloschweinitzin. We have thus demonstrated enzymatic formation of the basidiomycete's metabolite rufoschweinitzin and made the regiochemistry of alloschweinitzin accessible with an ascomycete-derived enzyme.

The enigmatic Cortinarius magellanicus complex occurring in Nothofagaceae forests of the Southern Hemisphere.

Cortinarius magellanicus Speg. is an edible, ectomycorrhizal fungus, widely distributed in Argentina, Chile and New Zealand. However, earlier studies already indicated that the epithet 'magellanicus' might have been applied in a wide sense, thus circumscribing several species. A neotype was designated by Moser and Horak (1975) due Spegazzini's type was lost. Argentinian Nothofagaceae forests' samples, from autumn of 2017, morphologically recognized as C. magellanicus were used for a phylogenetic analysis, including sequences from type material and closely related species. Our results showed that C. magellanicus represents a complex of species, with at least three phylogenetic lineages, each with strong regionalism and distinct host associations. Cortinarius magellanicus s. str. is restricted to Patagonia of Argentina and Chile. The misidentified reports from New Zealand and Australia represent distinct and different lineages. In the present contribution, the re-description of C. magellanicus is based on neotype material and two new species are proposed. Cortinarius vitreopileatus var. similissimus is described as variety from New Zealand resembling C. magellanicus, however without close phylogenetic relationship to it. The taxonomic delimitation for C. magellanicus species complex is of high relevance due to the abundance of these fungi and their ectomycorrhizal role in Nothofagaceae forests in Gondwanian region.

A systematic overview of Descolea (Agaricales) in the Nothofagaceae forests of Patagonia.

The descolea clade includes species of ectomycorrhizal basidiomycetes in the genera Descolea, Setchelliogaster, Descomyces, and Timgrovea that are known primarily from the Southern Hemisphere. Taxa in this group produce basidiomes that range in morphology from typical epigeous mushrooms (Descolea) and secotioid taxa (Setchelliogaster) to fully gasteroid species (Descomyces and Timgrovea). High intraspecific morphological variation has been reported in several species within this clade, suggesting that careful morphological and molecular studies are needed to refine species concepts. Molecular analyses of fresh Patagonian collections in conjunction with taxonomic studies have confirmed high variability in key morphological features, including overall sporocarp form, spore shape and dimensions, universal veil remnants, and cuticle configuration. Based on our synthesis, we emend the genus Descolea to include sequestrate species. We describe the new sequestrate taxon Descolea inferna sp. nov. from Nothofagaceae forests in Patagonia and we propose Cortinarius squamatus as a synonym of our new combination Descolea brunnea. We also formalize the identity of Descolea pallida as a synonym of Descolea antarctica and provide new specimens of Cortinarius archeuretus, a species that has not been encountered since the original discovery during the expeditions of Roland Thaxter in 1905-1906. Here we re-describe and transfer this species to Descolea as D. archeureta. We also discuss diagnostic features that can be used to delimitate the four known South American taxa in the descolea clade.

Human and experimental toxicology of orellanine.

Orellanine is a nephrotoxic toxin produced by some mushroom species of the Cortinarius genus, typically found in Europe and North America. The nephrotoxicity of Cortinarius orellanus is well known and was first recognized in the 1950s when this mushroom was identified as the cause of a mass poisoning in Poland. Typically, onset of symptoms is delayed for 1-2 weeks after ingestion. Some patients suffer mild gastrointestinal discomfort in the latency period before developing signs of renal impairment due to severe interstitial nephritis, acute focal tubular damage, and interstitial fibrosis. There is no specific antidote to orellanine poisoning. The mainstay of treatment is the prevention of secondary complications of kidney failure, adequate dialysis and, in the case of incomplete recovery, management of chronic renal insufficiency. : In this work, we aim to review about Cortinarius species, including epidemiological studies, chemical structure, toxicokinetics, toxic doses, mechanisms of toxicity, diagnosis, prognosis, and treatment options.

Productividad del hongo nativo cortinarius austroturmalis en bosques de nothofagus siempreverde y caducifolio de las reservas nacionales altos de lircay y los ruiles de la VII región, Chile / Productivity of the native mushroom cortinarius austroturmalis in evergreen and deciduous nothofagus forests of the national reserves altos de lircay and los ruiles of the VII region, Chile

Los bosques de Nothofagus de la zona mediterránea de Chile, que incluye la VII Región, están constituidos por especies caducifolias y siempreverdes, las cuales se encuentran asociadas a diversos hongos ectomicorrícicos dentro de los que destaca el hongo nativo Cortinarius austroturmalis Moser & Horak (Agaricales, Basidiomycota). Este hongo constituye un Producto Forestal No Maderero (PFNM) poco conocido, cuya productividad no ha sido determinada, lo que implica que la población rural cercana a las Reservas Nacionales Altos de Lircay y Los Ruiles de la VII Región, no lo identifique como un hongo apto para el consumo humano y, por consiguiente, no lo coseche. El objetivo de esta investigación fue conocer la productividad de basidiomas del hongo nativo Cortinarius austroturmalis asociado a especies de Nothofagus siempreverdes y caducifolias en las Reservas Nacionales Altos de Lircay y Los Ruiles de la VII Región. Las hipótesis propuestas fueron: 1) La productividad de basidiomas de Cortinarius austroturmalis en la Reserva Nacional Los Ruiles es mayor que en la Reserva Nacional Altos de Lircay, 2) La productividad de basidiomas de Cortinarius austroturmalis asociados a especies de Nothofagus siempreverdes es mayor que la productividad de este hongo asociado a especies de Nothofagus caducifolias en ambas reservas estudiadas.

Nothofagus forests in the Mediterranean region of Chile, including VII Region consist of deciduous and evergreen species, which are associated with different ectomycorrhizal fungi within which highlights the native mushroom Cortinarius austroturmalis Moser & Horak (Agaricales, Basidiomycota). This fungus is a Non-Wood Forest Product (NWFP) obscure, whose productivity has not been determined, implying that close to the National Reserves Altos de Lircay and Los Ruiles, VII Region, rural population does not identify it a fungus suitable for human consumption and therefore not harvested. The objective of this research was to determine the productivity of fruit body of the native mushroom Cortinarius austroturmalis associated with Nothofagus species of evergreen and deciduous in the National Reserves Altos de Lircay and Los Ruiles, VII Region. The proposed hypotheses were: 1) Productivity of Cortinarius austroturmalis in the National Reserve Los Ruiles is higher than in the National Reserve Altos de Lircay, 2) Productivity of Cortinarius austroturmalis associated with Nothofagus species evergreen is greater than the productivity of this fungus associated with deciduous Nothofagus species in both reserves studied.

Some new and interesting taxa of Cortinarius subgenus Phlegmacium from the European Mediterranean Basin.

We clarify the taxonomy and nomenclature of several taxa of the genus Cortinarius subgenus Phlegmacium. To this aim, we have used a combination of morphological and molecular data. The evolutionary relationships of the species were inferred by comparison of the nuITS by means of weighted maximum parsimony, maximum likelihood and two different types of Bayesian methods (with and without a priori alignments). Phylogenetic resolution and support of all or most of the species included in this study and their relationships were possible only when including the phylogenetic signal from ambiguously aligned regions in weighted maximum parsimony analyses (recoded INAASE characters) and when the analysis simultaneously optimized alignment and phylogeny (with BAli-phy). Three species are described as new, Cortinarius mediterraneensis, C. cistoglaucopus and C. palazonianus, and C. olivaecodionysae is proposed for C. dionysae f. olivaceus. Descriptions are provided for these taxonomic and nomenclatural novelties, along with discussions of morphological and phylogenetic affinities to closely related taxa. Scanning microphotographs of the basidiospores are provided for the discussed taxa, and color pictures of the basidiomes in their natural habitat are provided for C. cistoglaucopus, C. mediterraneensis and C. palazonianus.

Tracking the evolutionary history of Cortinarius species in section Calochroi, with transoceanic disjunct distributions.

BACKGROUND: Cortinarius species in section Calochroi display local, clinal and circumboreal patterns of distribution across the Northern Hemisphere where these ectomycorrhizal fungi occur with host trees throughout their geographical range within a continent, or have disjunct intercontinental distributions, the origins of which are not understood. We inferred evolutionary histories of four species, 1) C. arcuatorum, 2) C. aureofulvus, 3) C. elegantior and 4) C. napus, from populations distributed throughout the Old World, and portions of the New World (Central- and North America) based on genetic variation of 154 haplotype internal transcribed spacer (ITS) sequences from 83 population samples. By describing the population structure of these species across their geographical distribution, we attempt to identify their historical migration and patterns of diversification. RESULTS: Models of population structure from nested clade, demographic and coalescent-based analyses revealed genetically differentiated and geographically structured haplotypes in C. arcuatorum and C. elegantior, while C. aureofulvus showed considerably less population structure and C. napus lacked sufficient genetic differentiation to resolve any population structure. Disjunct populations within C. arcuatorum, C. aureofulvus and C. elegantior show little or no morphological differentiation, whereas in C. napus there is a high level of homoplasy and phenotypic plasticity for veil and lamellae colour. The ITS sequences of the type specimens of C. albobrunnoides and C. albobrunnoides var. violaceovelatus were identical to one another and are treated as one species with a wider range of geographic distribution under C. napus. CONCLUSIONS: Our results indicate that each of the Calochroi species has undergone a relatively independent evolutionary history, hypothesised as follows: 1) a widely distributed ancestral population of C. arcuatorum diverged into distinctive sympatric populations in the New World; 2) two divergent lineages in C. elegantior gave rise to the New World and Old World haplotypes, respectively; and 3) the low levels of genetic divergence within C. aureofulvus and C. napus may be the result of more recent demographic population expansions. The scenario of migration via the Bering Land Bridge provides the most probable explanation for contemporaneous disjunct geographic distributions of these species, but it does not offer an explanation for the low degree of genetic divergence between populations of C. aureofulvus and C. napus. Our findings are mostly consistent with the designation of New World allopatric populations as separate species from the European counterpart species C. arcuatorum and C. elegantior. We propose the synonymy of C. albobrunnoides, C. albobrunnoides var. violaceovelatus and C. subpurpureophyllus var. sulphureovelatus with C. napus. The results also reinforce previous observations that linked C. arcuatorum and C. aureofulvus displaying distributions in parts of North America and Europe. Interpretations of the population structure of these fungi suggest that host tree history has heavily influenced their modern distributions; however, the complex issues related to co-migration of these fungi with their tree hosts remain unclear at this time.

Mycelial growth and substrate acidification of ectomycorrhizal fungi in response to different minerals.

A colorimetric method was developed to permit semi-quantitative measurement of substrate acidification by different ectomycorrhizal and one saprotrophic fungus growing on media containing one of five different minerals. Overall, substrate acidification differed between fungal species and the degree of variation in acidification in response to different minerals was highly species-dependent. Mycena galopus and Cortinarius glaucopus produced the least biomass of all tested species and produced the highest amount of acidification per unit mycelial density. Substrate acidification by C. glaucopus was inversely related to mycelial density, with particularly high acidification at low mycelial density on medium enriched with tri-calcium phosphate. Substrate acidification by M. galopus was constant irrespective of mycelial density and varied only according to mineral treatment, with higher substrate acidification on tri-calcium phosphate compared to the other minerals.