GlobalAMFungi: a global database of arbuscular mycorrhizal fungal occurrences from high-throughput sequencing metabarcoding studies.

Arbuscular mycorrhizal (AM) fungi are crucial mutualistic symbionts of the majority of plant species, with essential roles in plant nutrient uptake and stress mitigation. The importance of AM fungi in ecosystems contrasts with our limited understanding of the patterns of AM fungal biogeography and the environmental factors that drive those patterns. This article presents a release of a newly developed global AM fungal dataset (GlobalAMFungi database, https://globalamfungi.com) that aims to reduce this knowledge gap. It contains almost 50 million observations of Glomeromycotinian AM fungal amplicon DNA sequences across almost 8500 samples with geographical locations and additional metadata obtained from 100 original studies. The GlobalAMFungi database is built on sequencing data originating from AM fungal taxon barcoding regions in: i) the small subunit rRNA (SSU) gene; ii) the internal transcribed spacer 2 (ITS2) region; and iii) the large subunit rRNA (LSU) gene. The GlobalAMFungi database is an open source and open access initiative that compiles the most comprehensive atlas of AM fungal distribution. It is designed as a permanent effort that will be continuously updated by its creators and through the collaboration of the scientific community. This study also documented applicability of the dataset to better understand ecology of AM fungal taxa.

Climate-driven shifts in plant and fungal communities can lead to topsoil carbon loss in alpine ecosystems.

Alpine tundra ecosystems suffer from ongoing warming-induced tree encroachment and vegetation shifts. While the effects of tree line expansion on the alpine ecosystem receive a lot of attention, there is also an urgent need for understanding the effect of climate change on shifts within alpine vegetation itself, and how these shifts will consequently affect soil microorganisms and related ecosystem characteristics such as carbon storage. For this purpose, we explored relationships between climate, soil chemistry, vegetation, and fungal communities across seven mountain ranges at 16 alpine tundra locations in Europe. Among environmental factors, our data highlighted that plant community composition had the most important influence on variation in fungal community composition when considered in combination with other factors, while climatic factors had the most important influence solely. According to our results, we suggest that rising temperature, associated with a replacement of ericoid-dominated alpine vegetation by non-mycorrhizal or arbuscular mycorrhizal herbs and grasses, will induce profound changes in fungal communities toward higher dominance of saprotrophic and arbuscular mycorrhizal fungi at the expense of fungal root endophytes. Consequently, topsoil fungal biomass and carbon content will decrease.

Author Correction: GlobalFungi, a global database of fungal occurrences from high-throughput-sequencing metabarcoding studies.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

GlobalFungi, a global database of fungal occurrences from high-throughput-sequencing metabarcoding studies.

Fungi are key players in vital ecosystem services, spanning carbon cycling, decomposition, symbiotic associations with cultivated and wild plants and pathogenicity. The high importance of fungi in ecosystem processes contrasts with the incompleteness of our understanding of the patterns of fungal biogeography and the environmental factors that drive those patterns. To reduce this gap of knowledge, we collected and validated data published on the composition of soil fungal communities in terrestrial environments including soil and plant-associated habitats and made them publicly accessible through a user interface at https://globalfungi.com . The GlobalFungi database contains over 600 million observations of fungal sequences across > 17 000 samples with geographical locations and additional metadata contained in 178 original studies with millions of unique nucleotide sequences (sequence variants) of the fungal internal transcribed spacers (ITS) 1 and 2 representing fungal species and genera. The study represents the most comprehensive atlas of global fungal distribution, and it is framed in such a way that third-party data addition is possible.

Alien ectomycorrhizal plants differ in their ability to interact with co-introduced and native ectomycorrhizal fungi in novel sites.

Alien plants represent a potential threat to environment and society. Understanding the process of alien plants naturalization is therefore of primary importance. In alien plants, successful establishment can be constrained by the absence of suitable fungal partners. Here, we used 42 independent datasets of ectomycorrhizal fungal (EcMF) communities associated with alien Pinaceae and Eucalyptus spp., as the most commonly introduced tree species worldwide, to explore the strategies these plant groups utilize to establish symbioses with EcMF in the areas of introduction. We have also determined the differences in composition of EcMF communities associated with alien ectomycorrhizal plants in different regions. While alien Pinaceae introduced to new regions rely upon association with co-introduced EcMF, alien Eucalyptus often form novel interactions with EcMF species native to the region where the plant was introduced. The region of origin primarily determines species composition of EcMF communities associated with alien Pinaceae in new areas, which may largely affect invasion potential of the alien plants. Our study shows that alien ectomycorrhizal plants largely differ in their ability to interact with co-introduced and native ectomycorrhizal fungi in sites of introduction, which may potentially affect their invasive potential.

Surgery in drug use-associated infective endocarditis: long-term survival is negatively affected by recurrence.

OBJECTIVES: The prevalence of infectious endocarditis (IE) in intravenous drug users (IDUs) is increasing, and the number of patients who need surgery is also rising. Relatively little is known about the short-term and long-term outcomes of these operations. METHODS: This study is a retrospective analysis of our institutional results, focussing on risk factors for perioperative death, major adverse events and long-term survival. A total of 50 of the 66 (75.75%) patients had postoperative follow-up, and the mean follow-up time was 53.9 ± 9.66 months. Patients were divided into 2 groups depending on whether they were having their first operation or were being reoperated for recurrent IE. RESULTS: From March 2006 to December 2015, a total of 158 patients underwent surgery for IE; 72 (45.6%) of them were identified as active IDUs. The operative mortality in IDUs was 8.33% (6 patients), with no significant difference between the 2 groups (P = 0.6569). Survival rates at 1 year, at 3 years and at the end of follow-up were 92%, 72% and 64%, respectively. There was significantly worse survival of patients with recurrent IE (log-rank test, P = 0.03). CONCLUSIONS: Although the short-term results of operation for IE in IDUs are good, long-term outcomes are not satisfactory. The survival of patients with recurrence of IE caused by return to intravenous drug use is significantly worse.