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We assessed how environmental drivers influence the occurrences of wood-inhabiting macrofungi in European beech forests, using an extensive dataset of fruit body records collected in 53 reserves across twelve European countries. We found that the 105 species included in this study varied greatly in their responses to covariates related to resource quality, climate and forest connectivity, both in the strength and direction of the observed effects. Climate was the most important driver for some species, while others responded more to connectivity, or simply to the presence of high quality substrates within the reserves. Species occurrences varied also across geographical regions, especially between the UK and the rest of Europe. Our results show that wood-inhabiting fungi in European beech forests respond individualistically to habitat filters and differ in their biogeographical distribution patterns, and they thus provide a detailed perspective of how wood-inhabiting fungal communities are structured across Europe.

The original material of Sphinctrina tigillaris, collected in 1864, was relocated, re-examined, found to represent a species of Chaenothecopsis, and is transferred to that genus as C. tigillaris comb. nov. It occurred on a specimen of a polypore, now identified as Perenniporia meridionalis, on a beam in a Northamptonshire church, and does not appear to have been collected since. Perenniporia meridionalis is a predominantly central and southern European species which has not previously been recognized in the British Isles, although other English specimens have now been located in collections at Kew and referred to the related P. medulla-panis. The name Sphinctrina tigillaris had been overlooked since its original description in 1865, and is nomenclaturally distinct from Lichen tigillaris, the basionym of Cyphelium tigillare. Notes on five other calicioid fungi found on polypores, and a key to the six now known, are also included.

Hericium cirrhatum, Hericium coralloides and Hericium erinaceus are rarely recorded in Europe, and H. coralloides and H. erinaceus are Red Listed in several European countries. By contrast, H. erinaceus is common in nature in Japan and North America and easily cultivated for edible mushroom production. The three species are saprotrophs that grow on wood of broadleaved trees, particularly beech (Fagus sylvatica) in Britain. How they establish in the standing tree is uncertain, but they have been detected as latently present in functional sapwood. They frequently fruit in axenic culture, perhaps indicating that lack of fruit bodies in the field truly indicates lack of mycelial individuals, although it may be that natural fruiting is impeded by encapsulation within central woody tissues. Despite prolific sporulation in wild fruit bodies, basidiospore germination on agar is poor and large progeny sets of homokaryons were relatively difficult to obtain. The duration of the homokaryotic phase is unknown but may be prolonged due to low frequency of contact between mating compatible partners in natural substrata. Homokaryotic mycelia grow at least as rapidly as heterokaryons. Both homokaryons and heterokaryons are average to good combatants, the former slightly better than the latter. Poor growth and combative ability are unlikely to be the causes of apparent rarity in Europe, but poor germination and infrequent establishment may be.

Combined morphological studies and analysis of DNA sequences of the ITS1 region of the ribosomal gene cluster revealed taxonomic diversity within British material named Hydnellum scrobiculatum and indicated the presence of cryptic European taxa within the circumscriptions of Hydnellum concrescens, Phellodon melaleucus and Phellodon niger. Membership of two P. melaleucus terminal clusters was correlated with young fruit body pigmentation and corresponding preliminary evidence was obtained using H. concrescens: Basidiospores of English and Scottish samples named H. scrobiculatum differ from those of the neotype. The English spores matched those of H. concrescens. Sequencing the Scottish samples revealed at least three taxa new to Britain: Hydnellum gracilipes, Hydnellum cumulatum and an apparently undescribed taxon with poorly defined spore ornamentation. Molecular comparisons with American Phellodon atratus suggested that it should be removed from the British checklist. These results challenge existing species-based analyses underpinning our understanding of stipitate hydnoid distribution, ecology and conservation requirements.

Piptoporus quercinus, the rare oak polypore, is one of only four non-lichenised fungi listed on Schedule 8 of the Wildlife and Countryside Act 1981, in the UK. It is thereby accorded the highest level of legal protection in the UK. It fruits exclusively on oak (Quercus spp.), primarily veteran trees in old growth wood pasture and parkland in the midlands and southern England. Beyond information on fruit body occurrence, little is known of the ecology of this species. Germination of chlamydospores and basidiospores was investigated under a range of conditions (temperature, pH, different media). The mating system was ascertained by pairing single spore derived isolates, and somatic compatibility investigated by pairing fruit body isolates. Germination of basidiospores was consistently below 1 % with most success occurring on 2 % malt extract agar adjusted to pH 4 at 20 °C. Chlamydospores had a much higher average percentage of germination (47 % ± 22), and germinated even after prolonged exposure to extreme conditions (desiccation or exposure to −20 °C or 40 °C for 48 h, 7 d or 14 d). The mating system was unifactorial (bipolar), although only four mating alleles were discovered in the six populations sampled, two alleles being unique to one fruit body. There were no signs of somatic incompatibility between the majority of isolates, exceptions being an isolate from Wentwood, South Wales, and an isolate from Germany collected in 1975, both of which displayed apparent signs of somatic incompatibility in all experimental pairings. The lack of somatic incompatibility between the majority of UK isolates, together with the low number of mating alleles, may point to inbreeding within the UK population. Apparently compatible isolates were not, however, clonal, as shown by variation in their mycelial extension rates on agar at various temperatures.

The biosynthesis of a fungal secondary metabolite, chlorofusin, which disrupts the interaction between the proteins p53 and MDM2, has been investigated; the acetogenic origin of the chromophore backbone as well as of an aminodecanoic acid residue is demonstrated.

WE read with interest the letter by Irwin and Leech on fatal poisoning with Clitocybe rivulosa (= Clitocybe dealbata ) ( VR , August 2, 2014, vol 175, pp 122-123). The Veterinary Poisons Information Service (VPIS) regularly receives inquiries about animals that ingest fungi, particularly in the spring and autumn. Although the frequency of inquiries concerning fungi is high at these times, annually they comprise approximately 1 per cent of inquiries. In the majority of cases the species of fungus is unknown. In 2012 to 2013 the VPIS …

A series of novel drimane sesquiterpene esters (1-6) was isolated from fermentations of Aspergillus ustus var. pseudodeflectus and their structures elucidated by spectroscopic methods including the HMQC, HMBC and INADEQUATE NMR experiments. The major component of the fermentation, 1, was (2'E,4'E,6'E)-6-(1'-carboxy-2',4',6'-trien)-9-hydroxydrim-7-ene-11 ,12-olide. Compounds 1, 2, 3 and 5 exhibited endothelin receptor binding inhibitory activity against rabbit endothelin-A and rat endothelin-B receptors with IC50 values in the range 20-150 microM. These compounds had similar levels of activity in assays for binding to human endothelin A and endothelin B receptors. The isolation of 9,11-dihydroxy-6-oxodrim-7-ene, 7, a probable biosynthetic precursor to the drimane esters is also reported.

Xenovulene A, a novel inhibitor of benzodiazepine binding to the GABA-benzodiazepine receptor is produced by submerged fermentation of Acremonium strictum. It was isolated from the mycelium by solvent extraction and purified by chromatography on Sephadex LH-20 and octadecyl silica. The structure of xenovulene A was determined to be a novel oxygenated sesquiterpene containing a humulene moiety by interpretation of various spectroscopic data, especially from 2D NMR experiments. Xenovulene A inhibited binding of the benzodiazepine, flunitrazepam, with an IC50 of 40 nM in an in vitro assay using bovine synaptosome membrane preparations.

A series of reduced benzo[j]fluoranthen-3-ones (1-4) was isolated from fermentations of a fungal strain CBUK20700 (CBS 100220), classified as Cladosporium cf. cladosporioides, during a microbial extract screening programme to identify inhibitors of anti-CD2 8-induced interleukin-2 (IL-2) production by Jurkat E6-1 cells as potential immunosuppressive agents. These compounds were also found to be tyrosine kinase inhibitors. The structures of compounds 1-4 were elucidated by spectroscopic methods including the HMQC, HMBC and NOESY NMR experiments. The most potent compound in the series, (6bS, 7R, 8S)-7-methoxy-4, 8, 9-trihydroxy-1, 6b, 7, 8-tetrahydro-2H-benzo[j]fluoranthen-3-one (1) inhibited anti-CD28-induced IL-2 production and Abl tyrosine kinase with IC50 values of 400 and 60 nM respectively. The 6b-stereoisomeric 2 was a moderate inhibitor of both IL-2 production and Abl tyrosine kinase while the 8-oxo derivative 3 was inactive in both assays. The 8-O-methyl ether 4 was a moderate inhibitor of IL-2 production but exhibited potent inhibition of Abl tyrosine kinase with an IC50 of 45 nM.

Hydnellum and Phellodon species, generally considered ectomycorrhizal partners of a range of woody angiosperms and gymnosperms particularly within Fagaceae and Pinaceae , appear to be declining in continental Europe. They are listed as priority species in the UK Biodiversity Action Plan, but their UK conservation status remains uncertain. Interpretation of species distribution data is hampered by a lack of consensus regarding some key discriminatory morphological characters and difficulties with their interpretation. DNA sequencing of the ITS1 region of the ribosomal gene cluster discriminated between the known British species of Phellodon but revealed more terminal clusters than currently recognised taxa. Although the main focus within Hydnellum was on the very similar species pair H. concrescens and H. scrobiculatum , a few samples of H. caeruleum , H. ferrugineum , H. peckii , and H. spongiosipes were included in the study for reference. DNA sequencing of material identified on spore-based criteria as H. concrescens yielded two main groups, but samples received as H. scrobiculatum were generally more variable. Of these, two were reassigned and the remaining group, with very similar spores (although shorter than in published descriptions of H. scrobiculatum ), had highly variable sequence data. The results and conservation importance of these fungi highlight the need for a taxonomic reassessment of P. melaleucus , P. niger , H. concrescens , and H. scrobiculatum collections from Britain and continental Europe using a combined molecular and morphological approach. Specific PCR primers were constructed to discriminate fruit bodies, mycelium, and mycorrhizal roots of P. niger and P. confluens from each other and from other stipitate hydnoids.

A series of reduced benzo[j]fluoranthen-3-ones (1-4) was isolated from fermentations of a fungal strain CBUK20700 (CBS 100220), classified as Cladosporium cf. cladosporioides, during a microbial extract screening programme to identify inhibitors of anti-CD2 8-induced interleukin-2 (IL-2) production by Jurkat E6-1 cells as potential immunosuppressive agents. These compounds were also found to be tyrosine kinase inhibitors. The structures of compounds 1-4 were elucidated by spectroscopic methods including the HMQC, HMBC and NOESY NMR experiments. The most potent compound in the series, (6bS, 7R, 8S)-7-methoxy-4, 8, 9-trihydroxy-1, 6b, 7, 8-tetrahydro-2H-benzo[j]fluoranthen-3-one (1) inhibited anti-CD28-induced IL-2 production and Abl tyrosine kinase with IC50 values of 400 and 60 nM respectively. The 6b-stereoisomeric 2 was a moderate inhibitor of both IL-2 production and Abl tyrosine kinase while the 8-oxo derivative 3 was inactive in both assays. The 8-O-methyl ether 4 was a moderate inhibitor of IL-2 production but exhibited potent inhibition of Abl tyrosine kinase with an IC50 of 45 nM.