The genus Paraconiothyrium: species concepts, biological functions, and secondary metabolites

Evaluating the role of rhizosphere microbial home-field advantage in Betula luminifera adaptation to antimony mining areas

It has been established that the coevolution of plants and the rhizosphere microbiome in response to abiotic stress can result in the recruitment of specific functional microbiomes. However, the potential of inoculated rhizosphere microbiomes to enhance plant fitness and the inheritance of adaptive traits in subsequent generations remains unclear. In this study, cross-inoculation trials were conducted using seeds, rhizosphere microbiome, and in situ soil collected from areas of Betula luminifera grown in both antimony mining and control sites. Compared to the control site, plants originating from mining areas exhibited stronger adaptive traits, specifically manifested as significant increases in hundred-seed weight, specific surface area, and germination rate, as well as markedly enhanced seedling survival rate and biomass. Inoculation with mining microbiomes could enhance the fitness of plants in mining sites through a "home-field advantage" while also improving the fitness of plants originating from control sites. During the initial phase of seedling development, bacteria play a crucial role in promoting growth, primarily due to their mechanisms of metal resistance and nutrient cycling. This study provided evidence that the outcomes of long-term coevolution between plants and the rhizosphere microbiome in mining areas can be passed on to future generations. Moreover, it has been demonstrated that transgenerational inheritance and rhizosphere microbiome inoculation are important factors in improving the adaptability of plants in mining areas. The findings have important implications for vegetation restoration and ecological environment improvement in mining areas.

Diversity of Endophytes of Actinidia arguta in Different Seasons

The seasonal changes in environmental conditions can alter the growth states of host plants, thereby affecting the living environment of endophytes and forming different endophytic communities. This study employs Illumina MiSeq next-generation sequencing to analyze the 16SrRNA and ITS rDNA of endophytes in 24 samples of Actinidia arguta stem tissues across different seasons. The results revealed a high richness and diversity of endophytes in Actinidia arguta, with significant seasonal variations in microbial community richness. This study identified 897 genera across 36 phyla for bacteria and 251 genera across 8 phyla for fungi. Notably, 69 bacterial genera and 19 fungal genera significantly contributed to the differences in community structure across seasons. A distinctive feature of coexistence in the endophytic community, both specific and conservative across different seasons, was observed. The bacterial community in winter demonstrated significantly higher richness and diversity compared to the other seasons. Environmental factors likely influence the optimal timing for endophyte colonization. Solar radiation, temperature, precipitation, and relative humidity significantly impact the diversity of endophytic bacteria and fungi. In addition, seasonal variations show significant differences in the nutritional modes of fungal endophytes and the degradation, ligninolysis, and ureolysis functions of bacterial endophytes. This study elucidates the potential role of endophytes in assisting Actinidia arguta in adapting to seasonal changes and provides a theoretical basis for further exploration of functional microbial strains.

Does nest occupancy by birds influence the microbial composition?

Nest microbiota plays a vital role in the breeding and development of birds, which not only provides protection to bird hosts but also negatively affects the host. At present, it is unclear whether the composition of the microbes in the nests is affected by nesting. For this reason, we hung artificial nest boxes to simulate the natural nesting environment and combined 16S rRNA and ITS high-throughput sequencing technology to further study the differences in microbial composition and richness between used nests and control nests of Japanese tits (Parus minor). The study found that the bacteria in used nests and control nests showed significant differences at the phylum level (p < 0.05). It is also worth noting that the predominant bacteria in used nests were Proteobacteria (51.37%), Actinobacteria (29.72%), Bacteroidetes (6.59%), and Firmicutes (3.82%), while the predominant bacteria in control nests were Proteobacteria (93.70%), Bacteroidetes (2.33%), and Acidobacteria (2.06%). Both used nests and control nests showed similar fungi at the phylum level, which consisted mainly of Ascomycota and Basidiomycota, although significant differences were found in their relative abundance between both groups. The results of alpha diversity analysis showed significant differences in bacteria between the two groups and not in fungi. However, the beta diversity analysis showed significant differences between both bacteria and fungi. In summary, our results showed that the used nests had a higher abundance of beneficial microbiota and a lower presence of pathogenic microbiota. Therefore, we speculate that birds will change the characteristics of the nest microbial composition in the process of nest breeding to ensure their smooth reproductive development.

Whole-genome sequencing and functional annotation of pathogenic Paraconiothyrium brasiliense causing human cellulitis

BACKGROUND

A pathogenic filamentous fungus causing eyelid cellulitis was isolated from the secretion from a patient's left eyelid, and a phylogenetic analysis based on the rDNA internal transcribed spacer region (ITS) and single-copy gene families identified the isolated strain as Paraconiothyrium brasiliense. The genus Paraconiothyrium contains the major plant pathogenic fungi, and in our study, P. brasiliense was identified for the first time as causing human infection. To comprehensively analyze the pathogenicity, and proteomics of the isolated strain from a genetic perspective, whole-genome sequencing was performed with the Illumina NovaSeq and Oxford Nanopore Technologies platforms, and a bioinformatics analysis was performed with BLAST against genome sequences in various publicly available databases.

RESULTS

The genome of P. brasiliense GGX 413 is 39.49 Mb in length, with a 51.2% GC content, and encodes 13,057 protein-coding genes and 181 noncoding RNAs. Functional annotation showed that 592 genes encode virulence factors that are involved in human disease, including 61 lethal virulence factors and 30 hypervirulence factors. Fifty-four of these 592 virulence genes are related to carbohydrate-active enzymes, including 46 genes encoding secretory CAZymes, and 119 associated with peptidases, including 70 genes encoding secretory peptidases, and 27 are involved in secondary metabolite synthesis, including four that are associated with terpenoid metabolism.

CONCLUSIONS

This study establishes the genomic resources of P. brasiliense and provides a theoretical basis for future studies of the pathogenic mechanism of its infection of humans, the treatment of the diseases caused, and related research.

Paraconiothyrium cyclothyrioides, a novel cutaneous fungal pathogen in a dog and a cat

A dog and a cat presented with pyogranulomatous mycotic pododermatitis. Panfungal PCR and next-generation sequencing identified Paraconiothyrium cyclothyrioides with 100% identity. Paraconiothyrium cyclothyrioides can rarely cause cutaneous infection and systemic disease in immunocompromised humans. This is the first report of infections in domestic animal species.

Simultaneous Heavy Metal-Polycyclic Aromatic Hydrocarbon Removal by Native Tunisian Fungal Species

Multi-contamination by organic pollutants and toxic metals is common in anthropogenic and industrial environments. In this study, the five fungal strains Chaetomium jodhpurense (MH667651.1), Chaetomium maderasense (MH665977.1), Paraconiothyrium variabile (MH667653.1), Emmia lacerata, and Phoma betae (MH667655.1), previously isolated in Tunisia, were investigated for the simultaneous removal and detoxification of phenanthrene (PHE) and benzo[a]anthracene (BAA), as well as heavy metals (HMs) (Cu, Zn, Pb and Ag) in Kirk’s media. The removal was analysed using HPLC, ultra-high performance liquid chromatography (UHPLC) coupled to a QToF mass spectrometer, transmission electron microscopy, and toxicology was assessed using phytotoxicity (Lepidium sativum seeds) and Microtox® (Allivibrio fisherii) assays. The PHE and BAA degradation rates, in free HMs cultures, reached 78.8% and 70.7%, respectively. However, the addition of HMs considerably affected the BAA degradation rate. The highest degradation rates were associated with the significant production of manganese-peroxidase, lignin peroxidase, and unspecific peroxygenase. The Zn and Cu removal efficacy was considerably higher with live cells than dead cells. Transmission electron microscopy confirmed the involvement of both bioaccumulation and biosorption processes in fungal HM removal. The environmental toxicological assays proved that simultaneous PAH and HM removal was accompanied by detoxification. The metabolites produced during co-treatment were not toxic for plant tissues, and the acute toxicity was reduced. The obtained results indicate that the tested fungi can be applied in the remediation of sites simultaneously contaminated with PAHs and HMs.

Fungal Planet description sheets: 1436-1477

Novel species of fungi described in this study include those from various countries as follows: Argentina, Colletotrichum araujiae on leaves, stems and fruits of Araujia hortorum. Australia, Agaricus pateritonsus on soil, Curvularia fraserae on dying leaf of Bothriochloa insculpta, Curvularia millisiae from yellowing leaf tips of Cyperus aromaticus, Marasmius brunneolorobustus on well-rotted wood, Nigrospora cooperae from necrotic leaf of Heteropogon contortus, Penicillium tealii from the body of a dead spider, Pseudocercospora robertsiorum from leaf spots of Senna tora, Talaromyces atkinsoniae from gills of Marasmius crinis-equi and Zasmidium pearceae from leaf spots of Smilaxglyciphylla. Brazil, Preussia bezerrensis from air. Chile, Paraconiothyrium kelleni from the rhizosphere of Fragaria chiloensis subsp. chiloensis f. chiloensis. Finland, Inocybe udicola on soil in mixed forest with Betula pendula, Populus tremula, Picea abies and Alnus incana. France, Myrmecridium normannianum on dead culm of unidentified Poaceae. Germany, Vexillomyces fraxinicola from symptomless stem wood of Fraxinus excelsior. India, Diaporthe limoniae on infected fruit of Limonia acidissima, Didymella naikii on leaves of Cajanus cajan, and Fulvifomes mangroviensis on basal trunk of Aegiceras corniculatum. Indonesia, Penicillium ezekielii from Zea mays kernels. Namibia, Neocamarosporium calicoremae and Neocladosporium calicoremae on stems of Calicorema capitata, and Pleiochaeta adenolobi on symptomatic leaves of Adenolobus pechuelii. Netherlands, Chalara pteridii on stems of Pteridium aquilinum, Neomackenziella juncicola (incl. Neomackenziella gen. nov.) and Sporidesmiella junci from dead culms of Juncus effusus. Pakistan, Inocybe longistipitata on soil in a Quercus forest. Poland, Phytophthora viadrina from rhizosphere soil of Quercus robur, and Septoria krystynae on leaf spots of Viscum album. Portugal (Azores), Acrogenospora stellata on dead wood or bark. South Africa, Phyllactinia greyiae on leaves of Greyia sutherlandii and Punctelia anae on bark of Vachellia karroo. Spain, Anteaglonium lusitanicum on decaying wood of Prunus lusitanica subsp. lusitanica, Hawksworthiomyces riparius from fluvial sediments, Lophiostoma carabassense endophytic in roots of Limbarda crithmoides, and Tuber mohedanoi from calcareus soils. Spain (Canary Islands), Mycena laurisilvae on stumps and woody debris. Sweden, Elaphomyces geminus from soil under Quercus robur. Thailand, Lactifluus chiangraiensis on soil under Pinus merkusii, Lactifluus nakhonphanomensis and Xerocomus sisongkhramensis on soil under Dipterocarpus trees. Ukraine, Valsonectria robiniae on dead twigs of Robinia hispida. USA, Spiralomyces americanus (incl. Spiralomyces gen. nov.) from office air. Morphological and culture characteristics are supported by DNA barcodes. Citation: Tan YP, Bishop-Hurley SL, Shivas RG, et al. 2022. Fungal Planet description sheets: 1436-1477. Persoonia 49: 261-350. https://doi.org/10.3767/persoonia.2022.49.08.

A taxonomic assessment of novel and remarkable fungal species in Didymosphaeriaceae (Pleosporales, Dothideomycetes) from plant litter

Fungal taxonomy has a long history and changed significantly in the last few decades. Most recent studies have witnessed morphology combined with DNA-based molecular analyses as the main research tool for fungal species identification. During field surveys, some interesting Didymosphaeriaceae species were found from plant litter in China and Thailand. Morphology combined with phylogenetic analyses (Bayesian and maximum likelihood) of ITS, LSU, SSU, tef1-α, and tub2 loci was used to identify fungal taxa. In this article, three new species and six new host records are described. The new species, Montagnula acaciae, Paraconiothyrium zingiberacearum, and Paraphaeosphaeria brachiariae, can be distinguished from other species of the respective genera based on their distinct size differences (ascomata, asci, and ascospores) and DNA sequence data. The new host records, Montagnula jonesii, Paraconiothyrium fuckelii, Spegazzinia deightonii, and S. tessarthra are reported from Ficus benjamina, Dimocarpus longan, Hedychium coronarium, and Acacia auriculiformis respectively, for the first time. Also, Paraconiothyrium archidendri and P. brasiliense are reported for the first time from Magnolia sp. in China. Moreover, Paraconiothyrium rosae is synonymized under P. fuckelii based on close phylogeny affinities and morphological characteristics. In-depth morphological descriptions, micrographs, and phylogenetic trees are provided to show the placement of new taxa.

Description of Four Novel Species in Pleosporales Associated with Coffee in Yunnan, China

In Yunnan Province, the coffee-growing regions are mainly distributed in Pu’er and Xishuangbanna. During the surveys of microfungi associated with coffee in Yunnan Province, seven taxa were isolated from coffee samples. Based on molecular phylogenetic analyses of combined ITS, LSU, SSU, rpb2, and tef1-α sequence data and morphological characteristics, four new species viz. Deniquelata yunnanensis, Paraconiothyrium yunnanensis, Pseudocoleophoma puerensis, and Pse. yunnanensis, and three new records viz. Austropleospora keteleeriae, Montagnula thailandica, and Xenocamarosporium acaciae in Pleosporales are introduced. In addition, Paracamarosporium fungicola was transferred back to Paraconiothyrium based on taxonomy and DNA sequences. Full descriptions, illustrations, and phylogenetic trees to show the placement of new and known taxa are provided. In addition, the morphological comparisons of new taxa with closely related taxa are given.

The numbers of fungi: contributions from traditional taxonomic studies and challenges of metabarcoding

The global diversity of fungi has been estimated using several different approaches. There is somewhere between 2–11 million estimated species, but the number of formally described taxa is around 150,000, a tiny fraction of the total. In this paper, we examine 12 ascomycete genera as case studies to establish trends in fungal species descriptions, and introduce new species in each genus. To highlight the importance of traditional morpho-molecular methods in publishing new species, we introduce novel taxa in 12 genera that are considered to have low species discovery. We discuss whether the species are likely to be rare or due to a lack of extensive sampling and classification. The genera are Apiospora, Bambusicola, Beltrania, Capronia, Distoseptispora, Endocalyx, Neocatenulostroma, Neodeightonia, Paraconiothyrium, Peroneutypa, Phaeoacremonium and Vanakripa. We discuss host-specificity in selected genera and compare the number of species epithets in each genus with the number of ITS (barcode) sequences deposited in GenBank and UNITE. We furthermore discuss the relationship between the divergence times of these genera with those of their hosts. We hypothesize whether there might be more species in these genera and discuss hosts and habitats that should be investigated for novel species discovery.

A New NPolyketide from Marine-Derived Paraconiothyrium sp

A new polyketide, paraconthone A (1) was obtained from the fermentation culture of Paraconiothyrium sp., together with two known compounds (2-3). Their structures were elucidated by spectroscopic analyses, including 1D- and 2D-NMR experiments, HR-ESI-MS, ECD calculation and by comparison with reported data. Compounds 1 to 3 were evaluated for their cytotoxic, anti-inflammation and antimicrobial activities in vitro, and 1 to 3 showed weak anti-microbial activities.

Genomic Analyses of the Fungus Paraconiothyrium sp. Isolated from the Chinese White Wax Scale Insect Reveals Its Symbiotic Character

The Chinese white wax scale, Ericerus pela, is an insect native to China. It harbors a variety of microbes. The Paraconiothyrium fungus was isolated from E. pela and genome sequenced in this study. A fungal cytotoxicity assay was performed on the Aedes albopictus cell line C6/36. The assembled Paraconiothyrium sp. genome was 39.55 Mb and consisted of 14,174 genes. The coding sequences accounted for 50.75% of the entire genome. Functional pathway analyses showed that Paraconiothyrium sp. possesses complete pathways for the biosynthesis of 20 amino acids, 10 of which E. pela lacks. It also had complementary genes in the vitamin B groups synthesis pathways. Secondary metabolism prediction showed many gene clusters that produce polyketide. Additionally, a large number of genes associated with ‘reduced virulence’ in the genome were annotated with the Pathogen–Host Interaction database. A total of 651 genes encoding carbohydrate-active enzymes were predicted to be mostly involved in plant polysaccharide degradation. Pan-specific genomic analyses showed that genes unique to Paraconiothyrium sp. were enriched in the pathways related to amino acid metabolism and secondary metabolism. GO annotation analysis yielded similar results. The top COG categories were ‘carbohydrate transport and metabolism’, ‘lipid transport and metabolism’, and ‘secondary metabolite biosynthesis, transport and catabolism’. Phylogenetic analyses based on gene family and pan genes showed that Paraconiothyrium sp is clustered together with species from the Didymosphaeriaceae family. A multi-locus sequence analysis showed that it converged with the same branch as P. brasiliense and they formed one group with fungi from the Paraconiothyrium genus. To validate the in vitro toxicity of Paraconiothyrium sp., a cytotoxicity assay was performed. The results showed that medium-cultured Paraconiothyrium sp. had no harmful effect on cell viability. No toxins were secreted by the fungus during growth. Our results imply that Paraconiothyrium sp. may establish a symbiotic relationship with the host to supply complementary nutrition to E. pela.