László G. Nagy

NFAP2, a novel cysteine‑rich anti‑yeast protein from Neosartorya fischeri NRRL 181: isolation and characterization

The increasing incidence of fungal infections and damages due to drug-resistant fungi urges the development of new antifungal strategies. The cysteine-rich antifungal proteins from filamentous ascomycetes provide a feasible base for protection against molds due to their potent antifungal activity on them. In contrast to this, they show no or weak activity on yeasts, hence their applicability against this group of fungi is questionable. In the present study a 5.6xa0kDa anti-yeast protein (NFAP2) is isolated, identified and characterized from the ferment broth of Neosartorya fischeri NRRL 181. Based on a phylogenetic analysis, NFAP2 and its putative homologs represent a new group of ascomycetous cysteine-rich antifungal proteins. NFAP2 proved to be highly effective against tested yeasts involving clinically relevant Candida species. NFAP2 did not cause metabolic inactivity and apoptosis induction, but its plasma membrane disruption ability was observed on Saccharomyces cerevisiae. The antifungal activity was maintained after high temperature treatment presumably due to the in silico predicted stable tertiary structure. The disulfide bond-stabilized, heat-resistant folded structure of NFAP2 was experimentally proved. After further investigations of antifungal mechanism, structure and toxicity, NFAP2 could be applicable as a potent antifungal agent against yeasts.

Genome expansion and lineage-specific genetic innovations in the forest pathogenic fungi Armillaria

Armillaria species are both devastating forest pathogens and some of the largest terrestrial organisms on Earth. They forage for hosts and achieve immense colony sizes via rhizomorphs, root-like multicellular structures of clonal dispersal. Here, we sequenced and analysed the genomes of four Armillaria species and performed RNA sequencing and quantitative proteomic analysis on the invasive and reproductive developmental stages of A.u2009ostoyae. Comparison with 22 related fungi revealed a significant genome expansion in Armillaria, affecting several pathogenicity-related genes, lignocellulose-degrading enzymes and lineage-specific genes expressed during rhizomorph development. Rhizomorphs express an evolutionarily young transcriptome that shares features with the transcriptomes of both fruiting bodies and vegetative mycelia. Several genes show concomitant upregulation in rhizomorphs and fruiting bodies and share cis-regulatory signatures in their promoters, providing genetic and regulatory insights into complex multicellularity in fungi. Our results suggest that the evolution of the unique dispersal and pathogenicity mechanisms of Armillaria might have drawn upon ancestral genetic toolkits for wood-decay, morphogenesis and complex multicellularity.Fungi of the genus Armillaria include devastating forest pathogens that cause root rot disease in many plants. Sequencing genomes and transcriptomes of several species, the authors reveal the genetic basis of dispersal, multicellular development and pathogenic mechanisms in Armillaria.

Psathyloma, a new genus in Hymenogastraceae described from New Zealand

A new genus Psathyloma is described based on collections of agarics from New Zealand. We describe two new species in the genus, Ps. leucocarpum and Ps. catervatim, both of which have been known and tentatively named for a long time awaiting a formal description. Morphological traits and phylogenetic analyses reveal that Psathyloma forms a strongly supported sister clade to Hebeloma, Naucoria and Hymenogaster. Morphologically Psathyloma resembles Hebeloma from which it differs mainly by producing smooth basidiospores with a germ pore. The geographical range of the genus has been demonstrated to include several regions in the southern hemisphere. A survey of published environmental sequences reveals that Psathyloma spp. were isolated from ectomycorrhizal root tips from Tasmania and Argentina, indicating an ectomycorrhizal association with southern beech.

Fungal Phylogeny in the Age of Genomics: Insights Into Phylogenetic Inference From Genome-Scale Datasets

The genomic era has been transformative for many fields, including our understanding of the phylogenetic relationships between organisms. The wide availability of whole-genome sequences practically eliminated data availability as a limiting factor for inferring phylogenetic trees, providing hundreds to thousands of loci for analyses, leading to molecular phylogenetics gradually being replaced by phylogenomics. The new era has also brought new challenges: systematic errors (resulting from, e.g., model violation) can be more pronounced in phylogenomic datasets and can lead to strongly supported incorrect relationships, creating significant incongruence among studies. Here, we review common practices, technical and biological challenges of phylogenomic analyses, with examples illustrated from fungi. We compare major approaches of phylogenetic inference, and illustrate the advantages conferred and challenges presented in phylogenomic case studies across the fungal tree of life, including cases where genome-scale data could conclusively resolve contentious relationships, and others that remain challenging despite the flood of genomic data.

Many roads to convergence

Plant genomes highlight complex mechanisms behind evolutionary convergence Many plants form specialized symbiotic root structures, called nodules, that harbor beneficial associations with nitrogen-fixing bacteria in the genera Rhizobium or Frankia (see the photo). How this nitrogen-fixing root nodule (NFN) symbiosis arose repeatedly during plant evolution is an age-old mystery: It shows signatures of convergence (the repeated emergence of similarity during evolution) yet builds on similar gene sets in phylogenetically distant plants. On page 144 of this issue, Griesmann et al. (1) sequenced the genomes of 10 plant species to reveal the genetic correlates of the origin and loss of NFN symbiosis. Their work reveals intricate gain and loss patterns of symbiosis-associated genes, calling for new models to explain convergent evolution.

Author Correction: Genome expansion and lineage-specific genetic innovations in the forest pathogenic fungi Armillaria

In the version of this Article originally published, it was incorrectly stated that “16,687 protein-coding genes were inferred for the most recent common ancestor (MRCA) of Armillaria”; the value was incorrect and it should have read “15,787”. This has now been corrected.