Do plant-based biogeographical regions shape aphyllophoroid fungal communities in Europe?

Aim: Aphyllophoroid fungi are associated with plants, either using plants as a resource (as parasites or decomposers) or as symbionts (as mycorrhizal partners). In spite of their strong association with plants, it is unknown how much plant distributions determine their biogeographical patterns compared with environmental factors such as climate and human land use. In this study, our aims are to (1) describe the spatial diversity patterns of aphyllophoroid fungi in Europe and (2) identify the factors shaping these patterns. Location: Europe, as well as the adjacent Subarctic to Arctic islands (Greenland, Faroe Islands, Iceland, Svalbard), Palestine and the south-east coast of the Caspian Sea. Methods: We compiled a dataset consisting of 14,030 fruitbody occurrences of 1,491 aphyllophoroid fungal species from 39 geographical areas (17 countries) belonging to eight biogeographical regions. We assessed the differences in fungal species richness and overall diversity and its nestedness and turnover components across biogeographical regions of Europe, as well as between southern and northern Europe (based on geographical latitude of 50 degrees as threshold). We used cluster and ordination analyses to classify the European aphyllophoroid communities biogeographically and evaluated the importance of climate, host-tree species, topography and human land-use intensity in explaining biogeographical variation. Results: The importance of biogeographical regions in determining European aphyllophoroid fungal communities varies for different diversity components. Species richness and nestedness are best explained by plant-based biogeographical regions, whereas overall beta diversity and species turnover are driven mostly by variation in climate, and nestedness mostly by tree species occupancy. Beta-diversity patterns of aphyllophoroid fungi do not differ between southern and northern Europe. Main conclusions: At the continental scale, aphyllophoroid fungi are less shaped by historical legacies than vascular plant and animal communities, and trends of overall beta diversity in southern and northern Europe are similar to patterns found for bryophytes.Peer reviewe

Biomarker analysis of cetuximab plus oxaliplatin/leucovorin/5-fluorouracil in first-line metastatic gastric and oesophago-gastric junction cancer: results from a phase II trial of the Arbeitsgemeinschaft Internistische Onkologie (AIO)

<p>Abstract</p> <p>Background</p> <p>The activity of the epidermal growth factor receptor (EGFR)-directed monoclonal antibody cetuximab combined with oxaliplatin/leucovorin/5-fluorouracil (FUFOX) was assessed in first-line metastatic gastric and oesophago-gastric junction (OGJ) cancer in a prospective phase II study showing a promising objective tumour response rate of 65% and a low mutation frequency of <it>KRAS </it>(3%). The aim of the correlative tumour tissue studies was to investigate the relationship between <it>EGFR </it>gene copy numbers, activation of the EGFR pathway, expression and mutation of E-cadherin, V600E BRAF mutation and clinical outcome of patients with gastric and OGJ cancer treated with cetuximab combined with FUFOX.</p> <p>Methods</p> <p>Patients included in this correlative study (<it>n </it>= 39) were a subset of patients from the clinical phase II study. The association between <it>EGFR </it>gene copy number, activation of the EGFR pathway, abundance and mutation of E-cadherin which plays an important role in these disorders, BRAF mutation and clinical outcome of patients was studied. <it>EGFR </it>gene copy number was assessed by FISH. Expression of the phosphorylated forms of EGFR and its downstream effectors Akt and MAPK, in addition to E-cadherin was analysed by immunohistochemistry. The frequency of mutant V600E BRAF was evaluated by allele-specific PCR and the mutation profile of the E-cadherin gene <it>CDH1 </it>was examined by DHPLC followed by direct sequence analysis. Correlations with overall survival (OS), time to progression (TTP) and overall response rate (ORR) were assessed.</p> <p>Results</p> <p>Our study showed a significant association between increased <it>EGFR </it>gene copy number (≥ 4.0) and OS in gastric and OGJ cancer, indicating the possibility that patients may be selected for treatment on a genetic basis. Furthermore, a significant correlation was shown between activated EGFR and shorter TTP and ORR, but not between activated EGFR and OS. No V600E BRAF mutations were identified. On the other hand, an interesting trend between high E-cadherin expression levels and better OS was observed and two <it>CDH1 </it>exon 9 missense mutations (A408V and D402H) were detected.</p> <p>Conclusion</p> <p>Our finding that increased <it>EGFR </it>gene copy numbers, activated EGFR and the E-cadherin status are potentially interesting biomarkers needs to be confirmed in larger randomized clinical trials.</p> <p>Trial registration</p> <p>Multicentre clinical study with the European Clinical Trials Database number 2004-004024-12.</p

Geastrum pleosporus sp. nov., a new species of Geastraceae identified by morphological and molecular phylogenetic data

[EN] An unusual species of Geastrum was found growing on decayed wood debris and leaves of Triplochiton scleroxylon in the Mbalmayo Forest Reserve, Cameroon. The species morphologically resembles G. saccatum and G. fimbriatum in having sessile endosperidium partly enclosed by the saccate base of the exoperidium. Microscopically, it is characterized by and distinguished from all other known species of the genus, in having subsmooth, punctate to moderately verruculose, slightly thick- to distinctly thick-walled polymorphous, constricted to eight-shaped, mostly oblong, ovoid, cylindrical, elliptic to clubshaped basidiospores. G. pleosporus was studied from a collection of about fifteen basidiomata covering different stages of development. It is described as new based on morphological analyses and phylogenetic inferences made from large ribosomal DNA sequence alignments. Phylogenetic relationship of G. pleosporus is investigated. In parsimony analyses of partial sequences of the large subunit rDNA from selected Gasteromycetes species, G. pleosporus is closely related to G. saccatum within the strongly supported clade of Geastrum species. The cluster of G. pleosporus and G. saccatum is well supported in parsimony analysis of the dataset with Geastrum species and related taxa using parsimony and maximum likelihood analysis.Peer reviewe

Sphaeropsis sapinea and fungal endophyte diversity in twigs of Scots pine (Pinus sylvestris) in Germany

Gefördert im Rahmen des Projekts DEA

Geometric morphometric analysis of spore shapes improves identification of fungi

Gefördert durch den Publikationsfonds der Universität Kasse

The Diplodia Tip Blight Pathogen Sphaeropsis sapinea Is the Most Common Fungus in Scots Pines’ Mycobiome, Irrespective of Health Status—A Case Study from Germany

The opportunistic pathogen Sphaeropsis sapinea (≡Diplodia sapinea) is one of the most severe pathogens in Scots pine, causing the disease Diplodia tip blight on coniferous tree species. Disease symptoms become visible when trees are weakened by stress. Sphaeropsis sapinea has an endophytic mode in its lifecycle, making it difficult to detect before disease outbreaks. This study aims to record how S. sapinea accumulates in trees of different health status and, simultaneously, monitor seasonal and age-related fluctuations in the mycobiome. We compared the mycobiome of healthy and diseased Scots pines. Twigs were sampled in June and September 2018, and filamentous fungi were isolated. The mycobiome was analyzed by high-throughput sequencing (HTS) of the ITS2 region. A PERMANOVA analysis confirmed that the mycobiome community composition significantly differed between growth years (p &lt; 0.001) and sampling time (p &lt; 0.001) but not between healthy and diseased trees. Sphaeropsis sapinea was the most common endophyte isolated and the second most common in the HTS data. The fungus was highly abundant in symptomless (healthy) trees, presenting in its endophytic mode. Our results highlight the ability of S. sapinea to accumulate unnoticed as an endophyte in healthy trees before the disease breaks out, representing a sudden threat to Scots pines in the future, especially with increasing drought conditions experienced by pines

New species and a new record of Phylloporia from Benin

Gefördert durch den Publikationsfonds der Universität Kasse