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Breast milk is a complex biological fluid. Additionally to its nutritional impact, it contains diverse bioactive elements related to early metabolic programming and molecular structures, such as microRNA related to the epigenetic signaling process. Now, we know that human milk is not sterile and contains a significant diversity of microorganisms such as bacteria (bacterioma), viruses (viroma) and fungi (mycobiome), all of which integrate the concept of the human milk microbiota. Apparently the origin of this microbiota is found in the entero-mammary circulation, as well as in the retrograde circulation of the skin of the mammary gland, although it is speculated in what percentage the microbiota of the oral cavity of the infant contributes in a significant way. From a functional point of view, it has been shown the transfer of this microbiota to the infant's digestive tract, which is related to better digestive tolerance, lower frequency and intensity of dysfunctionalities of the brain-intestine-microbiota axis, and improved immunity, among others.La leche materna es un fluido biológico complejo, ya que además de nutrir, contiene diversos elementos bioactivos relacionados con el fenómeno de programación metabólica temprana e incluso contiene estructuras moleculares relacionadas con el proceso de señalización epigenética tales como los microARN. Ahora sabemos que la leche humana no es estéril y contiene una diversidad significativa de microorganismos tales como bacterias (bacterioma), virus (viroma) y hongos (micobioma), todo lo cual integra el concepto de microbiota de leche humana. Al parecer el origen de esta microbiota se encuentra en la circulación enteromamaria, así como en la circulación retrógrada de la piel de glándula mamaria, aunque se especula en qué porcentaje la microbiota de la cavidad bucal del lactante contribuye de forma significativa. Desde el punto de vista funcional, se ha demostrado transferencia de esta microbiota hacia el tubo digestivo del lactante, lo que se relaciona con una mejor tolerancia digestiva, menor frecuencia e intensidad de disfuncionalidades del eje cerebro-intestino-microbiota, y mejora de la inmunidad, entre otras.

Background The so-called ‘mycobiome’ has progressively acquired interest and increased the complexity of our understanding of the human gut microbiota. Several questions are arising concerning the role of fungi (and in particular of Candida albicans), the so-called ‘mycobiome’, that has been neglected for a long time and only recently gained interest within the scientific community. There is no consensus on mycobiome normobiosis because of its instability and variability. This review aims to raise awareness about this interesting topic and provide a framework to guide physicians faced with such questions. Objectives To summarize current knowledge and discuss current and potential implications of the mycobiome in clinical practice. Sources We performed a review of the existing literature in Medline Pubmed. Content This review identifies several studies showing associations between specific mycobiome profiles and health. Fungi represent a significant biomass within the microbiota and several factors, such as diet, sex, age, co-morbidities, medications, immune status and inter-kingdom interactions, can influence its structure and population. The human gut mycobiota is indeed a key factor for several physiological processes (e.g. training of the immune system against infections) and pathological processes (e.g. immunological/inflammatory disorders, inflammatory bowel diseases, metabolic syndromes). Moreover, the mycobiome (and C. albicans in particular) could influence an even broader spectrum of conditions such as psychiatric diseases (depression, schizophrenia, bipolar disorder) or chronic viral infections (human immunodeficiency virus, hepatitis B virus); moreover, it could be implicated in tumorigenesis. Implications Candida albicans is a well-known opportunistic pathogen and a major component of the mycobiome but its role in the gastrointestinal tract is still poorly understood. From a potential screening biomarker to a key factor for several pathological processes, its presence could influence or even modify our clinical practice.

Atopic dermatitis (AD) is a chronic and relapsing inflammatory skin disease with an increasing prevalence worldwide. The aetiology and pathogenesis of AD have not been fully elucidated. Previous studies have suggested the role of fungi as a triggering factor in the development AD. Here we conducted a systematic review to investigate the skin mycobiome profiles in AD and to address whether there is an association between fungal dysbiosis and AD. We searched Medline/PubMed, Embase and Web of Science for research studies published in English between January 1st, 2010 and April 21st, 2021. A total of 11 human studies and 3 animal studies were included in this analysis. Fungal dysbiosis was observed in AD lesions with a depleted amount of Malassezia and a higher abundance of filamentous fungi. A positive correlation between Candida and Staphylococcus was also demonstrated in AD. We supposed that specific species of Malassezia spp. and Candida spp. may play a role in the pathogenesis of AD by interacting with the pathogenic bacteria. Topical application of emollients could improve the skin barrier function and restore the skin fungal flora by increasing the amount of Malassezia. Further studies focusing on the complex interplay between specific skin fungi and the host can provide better insight into the role of microorganisms in the pathogenesis of AD.

Sugarcane cultivars (Saccharum officinarum L.) are widely cultivated for both sugar and renewable energy in China. The response of rhizosphere fungal composition and diversity to different emerging sugarcane cultivars is limited. Therefore, utilizing high-throughput sequencing, we explored fungal communities' structure in soils adhering to six sugarcane cultivars' roots (Guitang 08-120, Regan14-62, Guitang 08-1180, Haizhe 22, Liucheng 05-136, Taitang 22) in Guangxi Province, China. Our results suggested that sugarcane varieties significantly altered rhizosphere soil attributes, with Haizhe 22 having substantially lower soil pH, organic matter (OM), available phosphorus (AP), and soil water contents (SWC) than others cultivars. Different sugarcane varieties did not substantially affected the Shannon fungal diversity index, but the apparent effect on fungal richness was significant. Beta diversity analysis revealed that "Haizhe 22" distinguished the fungal community from the other five cultivars. Soil pH, OM, cultivars, and soil moisture were crucial determinants in shaping soil fungal composition. The Haizhe 22 rhizosphere significantly enriched the operational taxonomic units (OTUs) assigned to two fungal genera (Cephalotheca and Sagenomella), while rhizosphere of other verities significantly enriched the OTUs assigned to four fungal genera (Chaetomium, Chaetosphaeria, Mortierella, and Talaromyces), suggesting their essential role in plant development, disease tolerance, and bioremediation. These findings may help in selecting or breeding innovative genotypes capable of supporting abundant rhizosphere fungi beneficial to plants that would likely improve crops' agronomic potential and maintain soil ecosystem sustainability.

Background The nasopharyngeal bacterial and fungal microbiota of normal horses and those with nasopharyngeal cicatrix syndrome (NCS) are unknown. Hypotheses/objectives To describe the microbiota from nasopharyngeal washes of healthy horses and of horses acutely affected with NCS. Animals Twenty-six horses acutely affected with NCS horses and 14 unaffected horses. Methods Prospective, observational cohort study. Horses were recruited by investigators through personal communications in central Texas. Bacterial (16s RNA) and fungal (internal transcribed spacer) microbiota from nasopharyngeal washes were evaluated. Polymerase chain reaction for detection of Pythium insidiosum was performed. Results Results indicated that 6 fungal genera (Alternaria, Bipolaris, Microascus, Spegazzinia, Paraconiothyrium, Claviceps) and 1 bacterial genera (Staphylococcus) were significantly different between affected and unaffected horses. The fungal genus Bipolaris had increased abundance in NCS affected horses and on NCS affected farms. Pythium insidiosum was absent in the nasopharyngeal wash of all horses, irrespective of health status. Conclusion and clinical importance Significant differences were identified in the fungal microbiota in horses affected with NCS and farms affected with NCS compared to those unaffected. Therefore, Bipolaris warrants further investigation.

Supplementation with micronutrients, including vitamins, iron and zinc, is a key strategy to alleviate child malnutrition. However, association of gastrointestinal disorders with iron has led to ongoing debate over their administration. To better understand their impact on gut microbiota, we analyse the bacterial, protozoal, fungal and helminth communities of stool samples collected from a subset of 80 children at 12 and 24 months of age, previously enrolled into a large cluster randomized controlled trial of micronutrient supplementation in Pakistan (ClinicalTrials.gov identifier NCT00705445). We show that while bacterial diversity is reduced in supplemented children, vitamins and iron (as well as residence in a rural setting) may promote colonization with distinct protozoa and mucormycetes, whereas the addition of zinc appears to ameliorate this effect. We suggest that the risks and benefits of micronutrient interventions may depend on eukaryotic communities, potentially exacerbated by exposure to a rural setting. Larger studies are needed to evaluate the clinical significance of these findings and their impact on health outcomes., Micronutrient supplements are key to global efforts to address child malnutrition. Here, in a cohort of children, previously enrolled into a large cluster randomized controlled trial of micronutrient supplementation in Pakistan, Popovic et al. find that vitamins and iron increase carriage of protozoa and fungi in the gut, potentially disrupting the bacterial microbiome.

Soil microorganisms are essential for the long-term sustainability of agricultural ecosystems. However, continuous grapevine replanting can disrupt the stability of soil microbial communities. We investigated the bacterial and fungal abundance, diversity, and community composition in rhizosphere soils with continuous grapevine replanting for 5, 6, 7 (Y5, Y6, and Y7; short-term), and 20 (Y20; long-term) years with high-throughput sequencing. Results showed that diversities and abundances of bacterial and fungal communities in Y20 were significantly lower than in other samples. The bacterial and fungal community compositions were markedly affected by the replanting time and planting year. After short-term grapevine replanting, relative abundances of potential beneficial bacteria and harmful fungi in rhizosphere soils were higher compared to long-term planting. Bacterial and fungal communities were significantly correlated with available nitrogen (AN), available phosphorus, available potassium (AK), and pH. AK and AN were the primary soil factors related to the shift of bacterial and fungal communities. Bacterial and fungal co-occurrence patterns were remarkably affected by replanting time, showing that fallow land harbored co-occurrence networks more complex than those in other groups, with the Y20 group showing the lowest complexity. Then, we isolated the dominant fungi in grapevine rhizosphere soil after continuous replanting and verified the harmful effects of three candidate strains through pot experiments. The results showed that 12 days post-treating the soil with fungal spore suspensions significantly inhibited grapevine seedlings' growth, whereas Fusarium solani inhibited plant growth. Overall, we showed that F. solani might be a potentially harmful fungus related to grapevine replant diseases. KEY POINTS: • Continuous grapevine planting reduced soil microbe diversities/abundances. • Beneficial bacteria and harmful fungi increased after short-term replanting. • F. solani may be a harmful fungus related to grapevine replant diseases.

Distributed across both the tropical Atlantic and Pacific oceans, the seagrass Halophilia ovalis stabilizes coastal sediment, thereby preventing shoreline erosion and is also an important food source for megaherbivores such as dugongs. However, seagrass meadows globally are under severe duress due to both climate change and anthropogenic activities. We characterized the mycobiome of Halophilia ovalis at seven sites in the Malay Peninsula using ITS1 rDNA amplicon sequences and investigated differences in fungal community structure. We found that geographic location was a significant factor shaping fungal communities and that marine sediment harboured significantly higher diversity when compared to H. ovalis leaves, roots and rhizomes. Taken together, it is likely that locality rather than specific plant structure determines fungal community structure in H. ovalis. Because the plant mycobiome is known to exert a strong effect on plant health, to maximize the success of future seagrass transplantation and restoration work we propose that these efforts consider the importance of seagrass mycobiomes at all stages.

Fertilization is known to affect antibiotic-resistance gene (ARG) patterns in the soil, even in the gut of soil fauna. Here, we conducted a microcosm experiment to investigate differences of effects of different fertilizers on collembolan gut ARG profiles and to further explore the microecological mechanisms that cause the differences. Although fertilization increased the abundance of ARGs, compared with the conventional manure, the application of antibiotic-reduced manure and vermicompost all curbed the enrichment of ARGs in the gut of collembolans. The results of the structural equation model revealed that changes in the microbial community caused by fertilizations have an important contribution to variations in the ARGs. We further found that the fungal community, like bacterial community, is also an important driver of ARG patterns in the collembolan gut. The fungi belonging to Dokmaia and Talaromyces were significantly correlated with the ARGs in the gut of collembolans. In addition, the application of vermicompost significantly increased the abundance of agricultural beneficial microbes in the soil environment. Together, our results provide an insight into the role of the fungal community on ARG patterns in the soil collembolan gut microbiome and highlight environmental friendliness of vermicomposting.

Citri Reticulatae Pericarpium (CRP) is a natural product that is used widely in food and is an ingredient in traditional Chinese medicine. CRP improves gradually with aging; this process typically takes 3 years or more. During the aging process, CRP can be colonized with fungi and mildew. Molds and mildew may result in an increased flavonoid content; however, this has been observed only in response to fungi of the genera Penicillium and Aspergillus. As fungal colonization may alter the quality and properties of CRP, it is critical to have an understanding of the fungal communities detected on the surface of CRP during the aging process. We used a high-throughput sequencing (HiSeq) platform to sequence internal transcribed spacers (ITS) region to identify the contaminants associated with CRP during the 3-year aging process. We also evaluated the distribution of the dominant fungi of the genera Aspergillus and Penicillium over time. At the phylum level, we identified Ascomycota (36.26%) and Basidiomycota (18.98%), along with smaller populations of Mucoromycota, Glomeromycota, and Mortierellomycota. At the genus level, the fungi detected include Wallemia (12.40%), Cystofilobasidium (4.62%), Zasmidium (4.52%), Cladosporium (3.72%), Hanseniaspora (3.55%), Fusarium (3.49%), Kurtzmaniella (2.03%), Candida (1.74%), Passalora (1.47%), Ceramothyrium (1.33%), Mucor (1.07%), and Aspergillus (1.03%). Fungi of the genus Penicillium were detected primarily during the first year of storage. By contrast, fungi of the genus Aspergillus were not detected during the early stages (fresh peel-8 months), but appeared gradually at later stages of the aging process. Taken together, our results indicate that HiSeq is an effective method to study the changes in fungal communities that develop on the CRP surface over time. These findings provide a basis for further research into the correlation between dominant fungi and the mechanisms underlying the successful aging of CRP.

The Antarctic and Arctic regions are collectively referred to as the “Two Poles” of the earth and have extremely harsh climate conditions and fragile ecosystems. Until now, the biogeography of the fungal communities in the bipolar regions is not well known. In this study, we focused on the fungal communities in 110 samples collected from four habitat types (i.e., soil, vascular plant, freshwater, moss) in the Antarctic and Arctic sites using high-throughput sequencing. The data showed that the diversity and composition of fungal communities were both geographically patterned and habitat-patterned. ANOSIM tests revealed statistically significant differences among fungal communities in the eight sample types (R = 0.5035, p < 0.001) and those in the bipolar regions (R = 0.32859, p < 0.001). Only 396 OTUs (14.8%) were shared between the bipolar sites. Fungal communities in the four habitat types clustered together in the Arctic site but were separate from those of the Antarctic site, indicating that geographic distance was a more important determinant of fungal communities in the bipolar sites. These findings offer insights into the present-day biogeography of fungal communities in the bipolar sites.

Arbuscular mycorrhizal fungi (AMF) represent important players in the structure and function of many ecosystems. Yet, we learn about their roles mostly from greenhouse-based experiments, with results subjected to cultivation bias. This study explores multiple aspects of this bias and separates the effect of increased nutrient availability from other cultivation specifics. For 15 grassland plant species from two functional groups (C3 grasses vs dicotyledonous forbs), we compared AMF communities of adults collected from non-manipulated vegetation with those in plants grown in a greenhouse. Nutrient availability was comparable to field conditions or experimentally elevated. We evaluated changes in AMF community composition, diversity, root colonisation, and the averages of functional traits characterising hyphal soil exploration. Additionally, we use the data from the greenhouse experiment to propose a new plant functional trait-the change of AMF colonisation in response to nutrient surplus. The AMF community differed profoundly between field-collected and greenhouse-grown plants, with a larger change of its composition in grass species, and AMF community composition in grasses also responded more to fertilisation than in forbs. Taxonomic and phylogenetic diversity declined more in forbs under cultivation (particularly with elevated nutrients), because in their roots, the AMF taxa from families other than Glomeraceae largely disappeared. A decline in AMF colonisation was not caused by greenhouse cultivation itself but selectively by the elevation of nutrient availability, particularly in grass host species. We demonstrate that the extent of decrease in AMF colonisation with elevated nutrients is a useful plant functional trait explaining an observed response of the plant community to manipulation.

Indoor air quality is a major issue for public health, particularly in northern communities. In this extreme environment, adequate ventilation is crucial to provide a healthier indoor environment, especially in airtight dwellings. The main objective of the study is to assess the impact of ventilation systems and their optimization on microbial communities in bioaerosols and dust in 54 dwellings in Nunavik. Dwellings with three ventilation strategies (without mechanical ventilators, with heat recovery ventilators, and with energy recovery ventilators) were investigated before and after optimization of the ventilation systems. Indoor environmental conditions (temperature, relative humidity) and microbiological parameters (total bacteria, Aspergillus/Penicillium, endotoxin, and microbial biodiversity) were measured. Dust samples were collected in closed face cassettes with a polycarbonate filter using a micro-vacuum while a volume of 20 m3 of bioaerosols were collected on filters using a SASS3100 (airflow of 300 L/min). In bioaerosols, the median number of copies was 4.01 × 103 copies/m3 of air for total bacteria and 1.45 × 101 copies/m3 for Aspergillus/Penicillium. Median concentrations were 5.13 × 104 copies/mg of dust, 5.07 × 101 copies/mg, 9.98 EU/mg for total bacteria, Aspergillus/Penicillium and endotoxin concentrations, respectively. The main microorganisms were associated with human occupancy such as skin-related bacteria or yeasts, regardless of the type of ventilation.

Background Urine from clinically healthy dogs is not sterile. Characterizing microbial diversity and abundance within this population of dogs is important to define normal reference ranges for healthy urine. Objectives To establish composition and relative representation of bacterial and fungal microbiomes in urine of clinically healthy dogs. Animals Fifty clinically healthy dogs. Methods Analytic study. Urine sampling via cystocentesis. Comprehensive evaluation of urine including standard urinalysis, culture and sensitivity, next-generation sequencing (NGS), and bioinformatics to define bacterial and fungal microbiome. Results Culture did not yield positive results in any samples. Next-generation sequencing of urine established low presence of bacteria, fungi, or both in all samples. Diversity and abundance of bacterial and fungal communities varied between urine samples from different dogs. Struvite crystals were associated with bacterial community structure (P = .07) and there was a positive correlation between struvite crystals and pH. Conclusions and clinical importance The microbiome in urine of clinically healthy dogs has diverse bacterial and fungal species These findings highlight limitations of conventional culture testing and the need for culture-independent molecular diagnostics to detect microorganisms in urine.

In forests, bacteria and fungi are key players in wood degradation. Still, studies focusing on bacterial and fungal successions during the decomposition process depending on the wood types (i.e. sapwood and heartwood) remain scarce. This study aimed to understand the effect of wood type on the dynamics of microbial ecological guilds in wood decomposition. Using Illumina metabarcoding, bacterial and fungal communities were monitored every 3 months for 3 years from Quercus petraea wood discs placed on forest soil. Wood density and microbial enzymes involved in biopolymer degradation were measured. We observed rapid changes in the bacterial and fungal communities and microbial ecological guilds associated with wood decomposition throughout the experiment. Bacterial and fungal succession dynamics were very contrasted between sapwood and heartwood. The initial microbial communities were quickly replaced by new bacterial and fungal assemblages in the sapwood. Conversely, some initial functional guilds (i.e. endophytes and yeasts) persisted all along the experiment in heartwood and finally became dominant, possibly limiting the development of saprotrophic fungi. Our data also suggested a significant role of bacteria in nitrogen cycle during wood decomposition.

Ectomycorrhizas play a fundamental role in the function of forest ecosystems, being essential for plant nutrition absorption and soil quality. Many afforestation and reforestation programmes have begun to recover and maintain coastal forests in China, using pine species including Pinus thunbergii. We investigated the ectomycorrhizal colonization status of P. thunbergii in coastal pine forests of the Yellow Sea of China. We identified a total of 53 ectomycorrhizal fungal species in 74 soil samples collected from three sites and found that Thelephoraceae (10 spp.) and Russulaceae (8 spp.) were the most species-rich ectomycorrhizal fungal lineages. Russula sp. 1 was the most abundant species, accounting for 15.3% of the total ectomycorrhizal tips identified. Most of the remaining species were rare. At this small scale, host identity had no significant effect on the ectomycorrhizal fungal community composition (A = 0.036, P = 0.258), but sampling sites did (A = 0.135, P = 0.041). In addition, Na(+) and K(+) content and soil pH had significant effects on the ectomycorrhizal fungal community. The ectomycorrhizal fungal community associated with different host plants will become an important new direction for research, as ectomycorrhiza may have the potential to improve host capacity to establish in salt-stressed environments. This will provide a theoretical basis and technical support for saline soil reforestation and rehabilitation using pine species with compatible, native ectomycorrhizal fungi in Yellow Sea coastal areas.

Fungi are considered to be the most resilient and economically important microbial community that can easily survive and optimally grow under a wide range of growth conditions. Thermophilic fungi from the geothermal sources have been less pondered upon and lie unexplored. Here, a microbiome approach was conducted to understand the concealed world of the environmental mycobiota from the two hot springs of North Sikkim district located in North-east India. The solfataric muds from the hot springs were analyzed. In both the samples, on the basis of genus level classification, genus Fusarium had the highest abundance followed by Colletotrichum, Pochonia, Pyricularia, Neurospora, etc. Analyzing the predicted genes, the functional proteins of New Yume Samdung mycobiome were found to be dominated by the genera Fusarium (22%), Trichoderma (12%), and Aspergillus (11%), whereas in the case of Old Yume Samdung, it was dominated by the genera Aspergillus (11%), Saccharomyces (6%), and Fusarium (5%). Interestingly, in the studied mycobiome, environmental yeasts were also detected. From the functional metagenomics, sulfate adenylatetransferase (SAT) proteins for sulfur assimilation were found in some of the fungal reads. Toxin protein reads such as AM-toxin biosynthesis proteins, AF-toxin biosynthesis proteins, Gliotoxin biosynthesis proteins, and aflatoxin biosynthesis proteins were detected in the mycobiomes.

Paediatric inflammatory bowel disease (IBD) is a chronic inflammatory disorder of the digestive tract, comprising of Crohn’s disease (CD), ulcerative colitis (UC), and, where classification is undetermined, inflammatory bowel disease unclassified (IBDU). Paediatric IBD incidence is increasing globally, with prevalence highest in the developed world. Though no specific causative agent has been identified for paediatric IBD, it is believed that a number of factors may contribute to the development of the disease, including genetics and the environment. Another potential component in the development of IBD is the microbiota in the digestive tract, particularly the gut. While the exact role that the microbiome plays in IBD is unclear, many studies acknowledge the complex relationship between the gut bacteria and pathogenesis of IBD. In this review, we look at the increasing number of studies investigating the role the microbiome and other biomes play in paediatric patients with IBD, particularly changes associated with IBD, varying disease states, and therapeutics. The paediatric IBD microbiome is significantly different to that of healthy children, with decreased diversity and differences in bacterial composition (such as a decrease in Firmicutes). Changes in the microbiome relating to various treatments of IBD and disease severity have also been observed in multiple studies. Changes in diversity and composition may also extend to other biomes in paediatric IBD, such as the virome and the mycobiome. Research into biome differences in IBD paediatric patients may help progress our understanding of the aetiology of the disease.

Background Atopic dermatitis (AD) patients have an altered skin bacterial community, with an abundance of Staphylococcus aureus associated with flares, highlighting that microbial organisms may be important for disease exacerbation. Despite strong evidence of association between bacterial skin colonisation and AD, very limited knowledge regarding the eukaryotic microbial community, including fungi and ectoparasites, in AD exists. In this study, we compared the skin and nasal eukaryotic microbial community between adult AD patients (n = 55) and non-AD healthy controls (n = 45) using targeted 18S rRNA amplicon sequencing. Analysis was based on the presence or absence of eukaryotic microorganisms. Results The cutaneous composition of the eukaryotic microbial community and the alpha-diversity differed significantly between AD patients and non-AD individuals, with increased species richness on AD skin. Alpha-diversity and beta-diversity were similar on lesional and non-lesional skin of patients. The ectoparasite Demodex folliculorum and the yeast Geotrichum candidum were significantly more prevalent on the skin of AD patients. The prevalence of D. folliculorum on lesional skin was greater among patients recently treated with topical corticosteroid. Malassezia was one of the most frequently detected genera at all sites, with M. globosa and M. restricta being the most prevalent. M. restricta was under represented in the anterior nares of AD patients as compared to the non-AD control population. Conclusion Significant differences in the eukaryotic microbial communities were found between AD patients and non-AD individuals, with the most striking finding being the significantly overrepresentation of D. folliculorum on AD skin. Whether D. folliculorum can contribute to skin inflammation in AD needs further investigation.

Soil physicochemical properties and fungal communities are pivotal factors for continuous cropping of American ginseng (Panax quinquefoliumL.). However, the response of soil physicochemical properties and fungal communities to replant disease of American ginseng has not yet been studied. High-throughput sequencing and soil physicochemical analyses were undertaken to investigate the difference of soil fungal communities and environmental driver factors in new and old ginseng fields; the extent of replant disease in old ginseng fields closely related to changes in soil properties and fungal communities was also determined. Results indicated that fungal communities in an old ginseng field were more sensitive to the soil environment than those in a new ginseng field, and fungal communities were mainly driven by soil organic matter (SOM), soil available phosphorus (AP), and available potassium (AK). Notably, healthy ginseng plants in new and old ginseng fields may influence fungal communities by actively recruiting potential disease suppressive fungal agents such asAmphinema,Cladophialophora,Cadophora,Mortierella,andWilcoxina. When these key groups and members were depleted, suppressive agents in the soil possibly declined, increasing the abundance of pathogens. Soil used to grow American ginseng in the old ginseng field contained a variety of fungal pathogens, includingAlternaria,Armillaria,Aphanoascus,Aspergillus,Setophoma,andRhexocercosporidium. Additionally, micro-ecological factors affecting disease outbreaks in the old ginseng field included a strengthening in competition relationships, a weakening in cooperation relationships, and a change of trophic strategies among fungal communities.

Coastal salinity typically alters the soil microbial communities, which subsequently affect the biogeochemical cycle of nutrients in the soil. The seasonal variation of the soil fungal communities in the coastal area, closely associated with plant population, is poorly understood. This study provides an insight into the fungal community's variations from autumn to winter and spring to summer at a well-populated area of salt-tolerant Tamarix chinensis and beach. The richness and diversity of fungal community were higher in the spring season and lower in the winter season, as showed by high throughput sequencing of the 18S rRNA gene. Ascomycota was the predominant phylum reported in all samples across the region, and higher difference was reported at order level across the seasonal variations. The redundancy analysis suggested that the abundance and diversity of fungal communities in different seasons are mainly correlated to total organic carbon and total nitrogen. Additionally, the saprotrophic and pathotrophic fungi decreased while symbiotic fungi increased in the autumn season. This study provides a pattern of seasonal variation in fungal community composition that further broadens our limited understanding of how the density of the salt-tolerant T. chinensis population of the coastal saline soil could respond to their seasonal variations.

The phyllosphere microbiome exerts a strong effect on plants' productivity, and its composition is determined by various factors. To date, most phyllosphere studies have focused on bacteria, while fungi and especially archaea have been overlooked. We studied the effects of plant host and season on the abundance and diversity of the epiphytic archaeal and fungal communities in a typical semi-arid Mediterranean ecosystem. We collected leaves in two largely contrasting seasons (summer and winter) from eight perennial species of varying attributes which could be grouped into the following: (i) high-canopy, evergreen sclerophyllοus shrubs with leathery leaves, and low-canopy, either semi-deciduous shrubs or non-woody perennials with non-leathery leaves, and (ii) aromatic and non-aromatic plants. We determined the abundance of epiphytic Crenarchaea, total fungi, Alternaria and Cladosporium (main airborne fungi) via q-PCR and the structure of the epiphytic archaeal and fungal communities via amplicon sequencing. We observed a strong seasonal effect with all microbial groups examined showing higher abundance in summer. Plant host and season were equally important determinants of the composition of the fungal community consisted mostly of Ascomycota, with Hypocreales dominating in winter and Capnodiales and Pleosporales in summer. In contrast, the archaeal community showed plant host driven patterns dominated by the Soil Crenarchaeotic Group (SCG) and Aenigmarchaeota. Plant habit and aromatic nature exhibited filtering effects only on the epiphytic fungal communities. Our study provides a first in-depth analysis of the key determinants shaping the phyllosphere archaeal and fungal communities of a semi-arid Mediterranean ecosystem.

International audience; The tree seed mycobiome has received little attention despite its potential role in forest regeneration and health. The aim of the present study was to analyze the processes shaping the composition of seed fungal communities in natural forests as seeds transition from the mother plant to the ground for establishment.We used metabarcoding approaches and confocal microscopy to analyze the fungal communities of seeds collected in the canopy and on the ground in four natural populations of sessile oak (Quercus petraea). Ecological processes shaping the seed mycobiome were inferred using joint species distribution models.Fungi were present in seed internal tissues, including the embryo. The seed mycobiome differed among oak populations and trees within the same population. Its composition was largely influenced by the mother, with weak significant environmental influences. The models also revealed several probable interactions among fungal pathogens and mycoparasites.Our results demonstrate that maternal effects, environmental filtering and biotic interactions all shape the seed mycobiome of sessile oak. They provide a starting point for future research aimed at understanding how maternal genes and environments interact to control the vertical transmission of fungal species that could then influence seed dispersal and germination, and seedling recruitment.

Here, we investigated the possible linkages among geophagy, soil characteristics, and gut mycobiome of indri (Indri indri), an endangered lemur species able to survive only in wild conditions. The soil eaten by indri resulted in enriched secondary oxide-hydroxides and clays, together with a high concentration of specific essential micronutrients. This could partially explain the role of the soil in detoxification and as a nutrient supply. Besides, we found that soil subject to geophagy and indris’ faeces shared about 8.9% of the fungal OTUs. Also, several genera (e.g. Fusarium, Aspergillus and Penicillium) commonly associated with soil and plant material were found in both geophagic soil and indri samples. On the contrary, some taxa with pathogenic potentials, such as Cryptococcus, were only found in indri samples. Further, many saprotrophs and plant-associated fungal taxa were detected in the indri faeces. These fungal species may be involved in the digestion processes of leaves and could have a beneficial role in their health. In conclusion, we found an intimate connection between gut mycobiome and soil, highlighting, once again, the potential consequent impacts on the wider habitat.

This study aimed to investigate the fungal diversity and its temporal and spatial dynamics in the rhizosphere soil of healthy cotton by high-throughput sequencing. We studied species richness, composition, and distribution of cotton rhizosphere fungal community with respect to location (Alaer, Kuerle, Tumushuke, Hami, Shihezi, Wusu, and Jinghe) and plant growth period (seedling stage, bud stage, flowering stage, and boll-opening stage) using the methods of PCR-based high-throughput sequencing and real-time quantitative PCR. A total of 1,838,454 fungal nuclear ribosomal internal transcribed spacer region sequences (rRNA ITS) were obtained from all cotton plants sampled at different growth stages in the seven locations in Xinjiang. The most abundant fungal group in the cotton rhizosphere was the Ascomycota (78.72%), followed by the Zygomycota (9.56%) and Basidiomycota (2.77%). These sequences revealed an enormous number of operational taxonomic units (OTUs) in cotton (1802 unique OTUs), with 67-464 OTUs in a single cotton sample, at a 3% threshold and a sequencing depth of 30,000 sequences. We identified 33 classes and 389 genera from the resulting 1,800,714 sequences. Sordariomycetes was the most frequent class in all samples, followed by Leotiomycetes and Eurotiomycetes. There were some differences in OTUs among different growth stages, but the differences were not significant, with 382 OTUs (14.66%) being common to each of the stages. A marked difference in the diversity of fungi in the rhizosphere soil of cotton was evident among the different locations, with the highest number of OTUs being detected in Jinghe (1084 OTUs) and clusters of OTUs representative of northern and eastern Xinjiang being detected. There were significantly more tags of Mortierella in Jinghe and Wusu than in the other sampling sites. The dynamics of the rhizosphere fungal communities were influenced by sampling sites. To the best of our knowledge, the current study is the first application of PCR-based Illumina to characterize and compare the fungal biodiversity in multiple rhizosphere soil samples from cotton.

We assessed fungal diversity in deep-sea sediments obtained from different depths in the Southern Ocean using the internal transcribed spacer 2 (ITS2) region of nuclear ribosomal DNA by metabarcoding through high-throughput sequencing (HTS). We detected 655,991 DNA reads representing 263 fungal amplicon sequence variants (ASVs), dominated by Ascomycota, Basidiomycota, Mortierellomycota, Mucoromycota, Chytridiomycota and Rozellomycota, confirming that deep-sea sediments can represent a hotspot of fungal diversity in Antarctica. The community diversity detected included 17 dominant fungal ASVs, 62 intermediate and 213 rare. The dominant fungi included taxa of Mortierella, Penicillium, Cladosporium, Pseudogymnoascus, Phaeosphaeria and Torula. Despite the extreme conditions of the Southern Ocean benthos, the total fungal community detected in these marine sediments displayed high indices of diversity and richness, and moderate dominance, which varied between the different depths sampled. The highest diversity indices were obtained in sediments from 550 m and 250 m depths. Only 49 ASVs (18.63%) were detected at all the depths sampled, while 16 ASVs were detected only in the deepest sediment sampled at 1463 m. Based on sequence identities, the fungal community included some globally distributed taxa, primarily recorded otherwise from terrestrial environments, suggesting transport from these to deep marine sediments. The assigned taxa included symbionts, decomposers and plant-, animal- and human-pathogenic fungi, suggesting that deep-sea sediments host a complex fungal diversity, although metabarcoding does not itself confirm that living or viable organisms are present.

Flowers' fungal and bacterial communities can exert great impacts on host plant wellness and reproductive success-both directly and indirectly through species interactions. However, information about community structure and co-occurrence patterns in floral microbiome remains scarce. Here, using culture-independent methods, we investigated fungal and bacterial communities associated with stamens and pistils of four plant species (Scaevola taccada, Ipomoea cairica, Ipomoea pes-caprae, and Mussaenda kwangtungensis) growing together under the same environment conditions in an island located in South China. Plant species identity significantly influenced community composition of floral fungi but not bacteria. Stamen and pistil microbiomes did not differ in community composition, but differed in co-occurrence network topological features. Compared with the stamen network, pistil counterpart had fewer links between bacteria and fungi and showed more modular but less concentrated and connected structure. In addition, degree distribution of microbial network in each host species and each microhabitat (stamen or pistil) followed a significant power-law pattern. These results enhance our understanding in the assembly principles and ecological interactions of floral microbial communities.

Background: Bacterial infection is associated with gastric carcinogenesis. However, the relationship between nonbacterial components and gastric cancer (GC) has not been fully explored. We aimed to characterize the fungal microbiome in GC. Methods: We performed ITS rDNA gene analysis in cancer lesions and adjacent noncancerous tissues of 45 GC cases from Shenyang, China. Obtaining the OTUs and combining effective grouping, we carried out species identifications, alpha and beta diversity analyses, and FUNGuild functional annotation. Moreover, differences were compared and tested between groups to better investigate the composition and ecology of fungi associated with GC and find fungal indicators. Results: We observed significant gastric fungal imbalance in GC. Principal component analysis revealed separate clusters for the GC and control groups, and Venn diagram analysis indicated that the GC group showed a lower OTU abundance than the control. At the genus level, the abundances of 15 fungal biomarkers distinguished the GC group from the control, of which Candida (p = 0.000246) and Alternaria (p = 0.00341) were enriched in GC, while Saitozyma (p = 0.002324) and Thermomyces (p = 0.009158) were decreased. Combining the results of Welch's t test and Wilcoxon rank sum test, Candida albicans (C. albicans) was significantly elevated in GC. The species richness Krona pie chart further revealed that C. albicans occupied 22% and classified GC from the control with an area under the receiver operating curve (AUC) of 0.743. Random forest analysis also confirmed that C. albicans could serve as a biomarker with a certain degree of accuracy. Moreover, compared with that of the control, the alpha diversity index was significantly reduced in the GC group. The Jaccard distance index and the Bray abundance index of the PCoA clarified separate clusters between the GC and control groups at the species level (p = 0.00051). Adonis (PERMANOVA) analysis and ANOVA showed that there were significant differences in fungal structure among groups (p = 0.001). Finally, FUNGuild functional classification predicted that saprotrophs were the most abundant taxa in the GC group. Conclusions: This study revealed GC-associated mycobiome imbalance characterized by an altered fungal composition and ecology and demonstrated that C. albicans can be a fungal biomarker for GC. With the significant increase of C. albicans in GC, the abundance of Fusicolla acetilerea, Arcopilus aureus, Fusicolla aquaeductuum were increased, while Candida glabrata, Aspergillus montevidensis, Saitozyma podzolica and Penicillium arenicola were obviously decreased. In addition, C. albicans may mediate GC by reducing the diversity and richness of fungi in the stomach, contributing to the pathogenesis of GC.

Highlights • The prevalence of fungal disease is increasing in CF and non-CF bronchiectasis. • Effective management of fungal disease requires an understanding of the mycobiome. • Culture methods alone are inadequate for the accurate diagnosis of fungal disease. • Our study provides a framework to characterize fungal airway disease using NGS. • NGS can improve detection and clinical management of fungal infections., Background The prevalence of fungal disease in cystic fibrosis (CF) and non-CF bronchiectasis is increasing and the clinical spectrum is widening. Poor sensitivity and a lack of standard diagnostic criteria renders interpretation of culture results challenging. In order to develop effective management strategies, a more accurate and comprehensive understanding of the airways fungal microbiome is required. The study aimed to use DNA sequences from sputum to assess the load and diversity of fungi in adults with CF and non-CF bronchiectasis. Methods Next generation sequencing of the ITS2 region was used to examine fungal community composition (n = 176) by disease and underlying clinical subgroups including allergic bronchopulmonary aspergillosis, chronic necrotizing pulmonary aspergillosis, non-tuberculous mycobacteria, and fungal bronchitis. Patients with no known active fungal disease were included as disease controls. Results ITS2 sequencing greatly increased the detection of fungi from sputum. In patients with CF fungal diversity was lower, while burden was higher than those with non-CF bronchiectasis. The most common operational taxonomic unit (OTU) in patients with CF was Candida parapsilosis (20.4%), whereas in non-CF bronchiectasis sputum Candida albicans (21.8%) was most common. CF patients with overt fungal bronchitis were dominated by Aspergillus spp., Exophiala spp., Candida parapsilosis or Scedosporium spp. Conclusion This study provides a framework to more accurately characterize the extended spectrum of fungal airways diseases in adult suppurative lung diseases.

Knowledge about the impact of altitude and ethnicity on human oral microbiota is currently limited. To obtain the baseline of normal salivary microbiota, we analyzed the bacteria and fungi composition in Tibetan (HY group) and Han population (CD group) living at different altitudes by using next-generation sequencing (NGS) technology combined with PICRUSt and FUNGuild analyses. There were significant differences in oral microbiota composition between the two groups at phylum and genus levels. At the phylum level, the HY group had higher relative abundances of Firmicutes and Ascomycota, whereas the Bacteroidetes and Basidiomycota in the CD group were richer. These changes at the phylum level reflected different dominant genus compositions. Compared with the Han population, Candida, Fusarium, Zopfiella, Streptococcus, Veillonella and Rothia in Tibetan were higher. Surprisingly, the Zopfiella was found almost exclusively in the Tibetan. The PICRUSt and FUNGuild analysis also indicated that the function of the bacterial and fungal communities was altered between the two groups. In conclusion, our results suggest that there are significant differences in oral microbial structure and metabolic characteristics and trophic modes among Tibetan and Han population living at different altitudes. We first established the oral microbiota framework and represented a critical step for determining the diversity of oral microbiota in the Tibetan and Han population.

Aims The aim of this study was to assess the effects of beneficial micro-organisms on the growth, nutrient accumulation and root-associated fungal species composition of pot orchids grown in the greenhouse. Methods and results A greenhouse pot experiment was conducted to investigate the beneficial effects of a mycorrhizal fungus, Epulorhiza repens isolate ML01, an endophytic fungus, Umbelopsis nana isolate ZH3A-3 and a mixed commercial inoculum Rem, alone or in combination. Nested PCR assays showed that both isolates ML01 and ZH3A-3 can successfully establish in inoculated soil. All the inoculants significantly increased the plant total dry weight of Cymbidium hybridum 'Golden Boy', whereas only co-inoculation with the endophytic fungus ZH3A-3 and the Rem enhanced the fresh weight and height of host plants. The mycorrhizal fungus positively affected P, K, Ca, Mg content in shoots and Zn content in roots, while the endophytic fungus improved N, P, Ca accumulation in shoots and roots. Co-inoculation with the Rem and ML01 improved root to shoot translocation of Fe and Zn. In addition, inoculation with ZH3A-3, ML01+Rem and ZH3A-3+Rem decreased the relative frequency of Fusarium sp. on orchid roots. Trichoderma sp. were isolated from the roots treated with ML01, ML01+Rem and ZH3A-3+Rem. Conclusions Both mycorrhizal and endophytic fungi had the potential to create favourable microflora in the orchid roots and stimulate the growth of transplanted plantlets under greenhouse condition. Significance and impact of the study The newly isolated endophytic strain ZH3A-3 showed significant application value in orchid production.

Summary Bacteria and fungi are of uttermost importance in determining environmental and host functioning. Despite close interactions between animals, plants, their associated microbiomes, and the environment they inhabit, the distribution and role of bacteria and especially fungi across host and environments as well as the cross‐habitat determinants of their community compositions remain little investigated. Using a uniquely broad global dataset of 13 483 metagenomes, we analysed the microbiome structure and function of 25 host‐associated and environmental habitats, focusing on potential interactions between bacteria and fungi. We found that the metagenomic relative abundance ratio of bacteria‐to‐fungi is a distinctive microbial feature of habitats. Compared with fungi, the cross‐habitat distribution pattern of bacteria was more strongly driven by habitat type. Fungal diversity was depleted in host‐associated communities compared with those in the environment, particularly terrestrial habitats, whereas this diversity pattern was less pronounced for bacteria. The relative gene functional potential of bacteria or fungi reflected their diversity patterns and appeared to depend on a balance between substrate availability and biotic interactions. Alongside helping to identify hotspots and sources of microbial diversity, our study provides support for differences in assembly patterns and processes between bacterial and fungal communities across different habitats.

Alpine habitats are one of the most vulnerable ecosystems to environmental change, however, little information is known about the drivers of plant-fungal interactions in these ecosystems and their resilience to climate change. We investigated the influence of the main drivers of ectomycorrhizal (EM) fungal communities along elevation and environmental gradients in the alpine zone of the European Alps and measured their degree of specialisation using network analysis. We sampled ectomycorrhizas of Dryas octopetala, Bistorta vivipara and Salix herbacea, and soil fungal communities at 28 locations across five countries, from the treeline to the nival zone. We found that: (1) EM fungal community composition, but not richness, changes along elevation, (2) there is no strong evidence of host specialisation, however, EM fungal networks in the alpine zone and within these, EM fungi associated with snowbed communities, are more specialised than in other alpine habitats, (3) plant host population structure does not influence EM fungal communities, and (4) most variability in EM fungal communities is explained by fine-scale changes in edaphic properties, like soil pH and total nitrogen. The higher specialisation and narrower ecological niches of these plant-fungal interactions in snowbed habitats make these habitats particularly vulnerable to environmental change in alpine ecosystems.

This study aimed to compare the fungal rhizosphere communities of Rhazya stricta, Enneapogon desvauxii, Citrullus colocynthis, Senna italica, and Zygophyllum simplex, and the gut mycobiota of Poekilocerus bufonius (Orthoptera, Pyrgomorphidae, "Usherhopper"). A total of 164,485 fungal reads were observed from the five plant rhizospheres and Usherhopper gut. The highest reads were in S. italica rhizosphere (29,883 reads). Species richness in the P. bufonius gut was the highest among the six samples. Ascomycota was dominant in all samples, with the highest reads in E. desvauxii (26,734 reads) rhizosphere. Sordariomycetes and Dothideomycetes were the dominant classes detected with the highest abundance in C. colocynthis and E. desvauxii rhizospheres. Aspergillus and Ceratobasidium were the most abundant genera in the R. stricta rhizosphere, Fusarium and Penicillium in the E. desvauxii rhizosphere and P. bufonius gut, Ceratobasidium and Myrothecium in the C. colocynthis rhizosphere, Aspergillus and Fusarium in the S. italica rhizosphere, and Cochliobolus in the Z. simplex rhizosphere. Aspergillus terreus was the most abundant species in the R. stricta and S. italica rhizospheres, Fusarium sp. in E. desvauxii rhizosphere, Ceratobasidium sp. in C. colocynthis rhizosphere, Cochliobolus sp. in Z. simplex rhizosphere, and Penicillium sp. in P. bufonius gut. The phylogenetic results revealed the unclassified species were related closely to Ascomycota and the species in E. desvauxii, S. italica and Z. simplex rhizospheres were closely related, where the species in the P. bufonius gut, were closely related to the species in the R. stricta, and C. colocynthis rhizospheres.

Yeast communities associated with cacti were studied in three ecosystems of Southeast, Central and North Brazil. A total of 473 yeast strains belonging to 72 species were isolated from 190 samples collected. Cactophilic yeast species were prevalent in necrotic tissues, flowers, fruits and insects of cacti collected in Southeast and North Brazil. Pichia cactophila, Candida sonorensis and species of the Sporopachydermia complex were the most prevalent cactophilic species in Southeast and Central regions. Kodamaea nitidulidarum, Candida restingae and Wickerhamiella cacticola were frequently associated with cactus flowers and fruits. The diversity of yeasts associated with the substrates studied was high. Twenty-one novel species were found. One is described here as Kluyveromyces starmeri sp. nov. based on 21 isolates obtained from necrotic tissues, flowers, fruits and associated insects of the columnar cacti Cereus saddianus, Micranthocereus dolichospermaticus and Pilosocereus arrabidae in two different ecosystems in Brazil. Phylogenetic analyses of sequences encoding the gene of the small subunit (SSU) rRNA gene, the internal transcribed spacer, the 5.8S rRNA gene and the D1/D2 domains of the large subunit (LSU) rRNA showed that the species is related to Kluyveromyces dobzhanskii, Kluyveromyces lactis and Kluyveromyces marxianus. Phylogenomic analyses based on 1264 conserved genes shared among the new species and 19 other members of the Saccharomycetaceae confirmed this phylogenetic relationship. The holotype is K. starmeri sp. nov. CBS 16103T (=UFMG-CM-Y3682T ). The Mycobank number is MB 836817.

Background and Aims Plant invasions can change soil microbial communities and affect subsequent invasions directly or indirectly via foliar herbivory. It has been proposed that invaders promote uniform biotic communities that displace diverse, spatially variable communities (the biotic homogenization hypothesis), but this has not been experimentally tested for soil microbial communities, so the underlying mechanisms and dynamics are unclear. Here, we compared density-dependent impacts of the invasive plant Alternanthera philoxeroides and its native congener A. sessilis on soil fungal communities, and their feedback effects on plants and a foliar beetle. Methods We conducted a plant–soil feedback (PSF) experiment and a laboratory bioassay to examine PSFs associated with the native and invasive plants and a beetle feeding on them. We also characterized the soil fungal community using high-throughput sequencing. Key Results We found locally differentiated soil fungal pathogen assemblages associated with high densities of the native plant A. sessilis but little variation in those associated with the invasive congener A. philoxeroides, regardless of plant density. In contrast, arbuscular mycorrhizal fungal assemblages associated with high densities of the invasive plant were more variable. Soil biota decreased plant shoot mass but their effect was weak for the invasive plant growing in native plant-conditioned soils. PSFs increased the larval biomass of a beetle reared on leaves of the native plant only. Moreover, PSFs on plant shoot and root mass and beetle mass were predicted by different pathogen taxa in a plant species-specific manner. Conclusion Our results suggest that plant invasions can rapidly increase the similarity of soil pathogen assemblages even at low plant densities, leading to taxonomically and functionally homogeneous soil communities that may limit negative soil effects on invasive plants.

Background: The fungal communities inhabiting natural Ophiocordyceps sinensis play critical ecological roles in alpine meadow ecosystem, contribute to infect host insect, influence the occurrence of O. sinensis, and are repertoire of potential novel metabolites discovery. However, a comprehensive understanding of fungal communities of O. sinensis remain elusive. Therefore, the present study aimed to unravel fungal communities of natural O. sinensis using combination of high-throughput sequencing and culture-dependent approaches. Results: A total of 280,519 high-quality sequences, belonging to 5 fungal phyla, 15 classes, 41 orders, 79 families, 112 genera, and 352 putative operational taxonomic units (OTUs) were obtained from natural O. sinensis using high-throughput sequencing. Among of which, 43 genera were identified in external mycelial cortices (EMC), Ophiocordyceps, Sebacinia, Archaeorhizomyces were predominant genera with the abundance of 95.86%, 1.14%, 0.85%, respectively. A total of 66 genera were identified from soil microhabitat (Soil), Inocybe, Archaeorhizomyces, unclassified Thelephoraceae, Tomentella, Thelephora, Sebacina, unclassified Ascomycota, unclassified Fungi were predominant genera with an average abundance of 53.32%, 8.69%, 8.12%, 8.12%, 7.21%, 4.6%, 3.08% and 3.05%, respectively. The fungal communities in external mycelial cortices were significantly distinct from the soil microhabitat. Meanwhile, seven types of culture media were used to isolate culturable fungi at 16°C, resulted in 77 fungal strains isolated by rDNA ITS sequence analysis, belonging to 33 genera, including Ophiocordyceps, Trichoderma, Cytospora, Truncatella, Dactylonectria, Isaria, Cephalosporium, Fusarium, Cosmospora and Paecilomyces, etc.. Among all culturable fungi, Mortierella and Trichoderma were predominant genera. Conclusions: The significantly differences and overlap in fungal community structure between two approaches highlight that the integration of high-throughput sequencing and culture-dependent approaches would generate more information. Our result reveal a comprehensive understanding of fungal community structure of natural O. sinensis, provide new insight into O. sinensis associated fungi, and support that microbiota of natural O. sinensis is an untapped source for novel bioactive metabolites discovery.

Interaction with orchid mycorrhizal fungi (OMF) is essential to all members of the Orchidaceae, yet we know little about whether or how OMF abundances in substrates shape orchid populations. While root-associated OMF diversity is catalogued frequently, technological constraints have impeded the assessments of OMF communities in substrates until recently, thereby limiting the ability to link OMF communities in a habitat to population responses. Furthermore, there is some evidence that edaphic and microclimatic conditions impact OMF in soil, yet we lack an understanding of the coupled influences of abiotic environment and OMF structure on orchid population dynamics. To discover the linkages between abiotic environment, OMF community structure, and population size, we characterized the microclimatic conditions, soil physicochemistry, and OMF communities hosted by roots and soil across large and small populations of a terrestrial orchid endemic to California Floristic Province in North America. By using high-throughput sequencing of the ITS2 region of nrDNA amplified from root and soil DNAs, we determined that both roots and soil of larger populations, which were high in phosphorus but low in zinc, organic matter, and silt, were dominated by Tulasnellaceae OTUs. In comparison, roots and soil from smaller populations of the orchid hosted higher relative abundances of the Ceratobasidiaceae. In this multiyear, range-wide study that simultaneously measured habitat environmental conditions, and soil and root OMF communities, our results suggest that soil chemistry is clearly linked to soil and root OMF communities, which then likely alter and shape orchid populations.

Citrinin (CIT), a known nephrotoxic mycotoxin, is mainly produced by Penicillium, Aspergillus, and Monascus species. It is a natural contaminant in cereal grains, foods, and feedstuff. Liupao tea (or Liubao tea) is a typical Chinese dark tea obtained via indigenous tea fermentation facilitated by microorganisms. Certain fungi present in Liupao tea that may produce CIT are a potential threat to consumer health. In the present study, various potential toxigenic mycoflora and the natural occurrence of CIT in Liupao tea were surveyed via the culture-dependent method, high performance liquid chromatography-fluorescence detection (HPLC-FLD), and ultrahigh performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). Total mold counts ranged from 3.5 × 102 CFU/g to 2.1 × 106 CFU/g tea in 28 tea samples. A total of 218 fungal isolates belonging to five genera and 23 species were identified. Some of these strains, such as Aspergillus ochraceus, Aspergillus oryzae, Penicillium citrinum, and Penicillium chrysogenum, may potentially be a CIT-producing species. In addition, 32.7% of 113 Liupao tea samples were contaminated with CIT at concentrations ranging from 7.8 to 206.1 μg/kg. These CIT concentrations in Liupao tea are chiefly attributed to climatic conditions and water activity during storage that favor fungal proliferation and mycotoxin production. However, CIT could not be detected in Liupao tea stored for over 10 years. These results provide the first information about the potential toxigenic mycoflora and natural occurrence of CIT in Liupao tea. Therefore, storage conditions and fungal community must be monitored to ensure the quality of Liupao tea.

Respiratory microbiome is an understudied area of research compared to other microbiomes of the human body. The respiratory tract is exposed to an array of environmental pollutants, including microbes. Yet, we know very little about the relationship between environmental and respiratory microbiome. The primary aim of our study was to compare the mycobiomes and bacteriomes between three sample types from the same participants, including home dust, saliva, and sputum. Samples were collected from 40 adolescents in a longitudinal cohort. We analyzed the samples using 16s bacterial rDNA and ITS fungal rDNA gene sequencing, as well as quantitative PCR with universal fungal and bacterial primers. Results showed that home dust had the greatest alpha diversity between the three sample types for both bacteria and fungi. Dust had the highest total fungal load and the lowest total bacterial load. Sputum had greater bacterial diversity than saliva, but saliva had greater fungal diversity than sputum. The distribution of major bacterial phyla differed between all sample types. However, the distribution of major fungal classes differed only between sputum and saliva. Future research should examine the biological significance of the taxa found in each sample type based on microbial ecology and associations with health effects.

Summary Background The microbiome is emerging as a crucial player of the immune checkpoint in cancer. Melanoma is a highly immunogenic tumour, and the composition of the gut microbiome has been correlated to prognosis and evolution of advanced melanoma and proposed as a biomarker for immune checkpoint therapy. Objectives We investigated the gut fungal and bacterial compositions in early-stage melanoma and correlated microbial profiles with histopathological features. Methods Sequencing of bacterial 16S rRNA and the fungal internal transcribed spacer region was performed on faecal samples of patients with stage I and II melanoma, and healthy controls. A meta-analysis with gut microbiota data from patients with metastatic melanoma was also carried out. Results We found a combination of gut fungal and bacterial profiles significantly discriminating patients with melanoma from controls. In patients with melanoma, we observed an abundance of Prevotella copri and yeasts belonging to the order Saccharomycetales. We found that the bacterial and fungal community correlated to melanoma invasiveness, whereas the specific fungal profile correlated to melanoma regression. Bacteroides was identified as general marker of immunogenicity, being shared by regressive and invasive melanoma. In addition, the bacterial communities in patients with stage I and II melanoma were different in structure and richer than those from patients with metastatic melanoma. Conclusions The composition of the gut microbiota in early-stage melanoma changes along the gradient from in situ to invasive (and metastatic) melanoma. Changes in the microbiota and mycobiota are correlated to the histological features of early-stage melanoma, and to the clinical course and response to immune therapies of advanced-stage melanoma, through direct or indirect immunomodulation.

Fungi are widely distributed in all terrestrial ecosystems, and they are essential to the recycling of nutrients in all terrestrial habitats on earth. We wanted to determine the relationship between soil fungal communities and geochemical factors (geographical location and soil physicochemical properties) in three widely separated geographical regions (the Antarctic, Arctic, and Tibet Plateau). Using high-throughput Illumina amplicon sequencing, we characterized the fungal communities in 53 soil samples collected from the three regions. The fungal richness and diversity indices were not significantly different among the three regions. However, fungal community composition and many fungal taxa (Thelebolales, Verrucariales, Sordariales, Chaetothyriales, Hypocreales, Pleosporales, Capnodiales, and Dothideales) significantly differed among three regions. Furthermore, geographical location (latitude and altitude) and six soil physicochemical properties (SiO42−-Si, pH, NO3−-N, organic nitrogen, NO2−-N, and organic carbon) were significant geochemical factors those were correlated with the soil fungal community composition. These results suggest that many geochemical factors influence the distribution of the fungal species within the Antarctic, Arctic, and Tibet Plateau.

BACKGROUND:Fungal involvement in asthma is associated with severe disease. The full spectrum of fungal species in asthma is not well described and is derived largely from insensitive culture techniques. OBJECTIVES:To use high-throughput sequencing to describe the airway mycobiota in asthmatics with and without fungal-sensitisation and healthy controls; to compare samples representing different airway compartments; to determine if the mycobiota was influenced by the fungal composition of outdoor air, and to compare findings with clinically relevant outcomes. METHODS:We amplified the internal transcribed spacer region 2 of the nuclear ribosomal operon to identify the fungal species present. Ninety-seven subjects were recruited and provided sputum (83 asthmatics; 14 healthy subjects), with 29 also undergoing a bronchoscopy. A subset of airway samples were compared with matched outdoor air and mouthwash samples. RESULTS:Two hundred and six taxa at the species level were identified in sputum, most at low relative abundance. Aspergillus fumigatus, Candida albicans and Mycosphaerella tassiana had the highest relative abundances and were the most prevalent species across all subjects. The airway mycobiota consisted of a complex community with high diversity between individuals. Notable shifts in the balance of fungi detected in the lung were associated with asthma status, asthma duration and biomarkers of inflammation. Aspergillus tubingensis, a member of the Aspergillus niger species complex, was most prevalent from bronchoscopic protected brush samples and significantly associated with a low sputum neutrophilia. Cryptococcus pseudolongus, from the Cryptococcus humicola species complex, was more abundant from bronchoscopy samples than sputum, and differentially more abundant in asthma than health. CONCLUSIONS AND CLINICAL RELEVANCE:The airway mycobiota was dominated by a relatively small number of species, but was distinct from the oropharyngeal mycobiota and air samples. Members of the Aspergillus niger and Cryptococus humicola species complexes may play unexpected roles in the pathogenesis of asthma.

There are lots of seamounts globally whose primary production is disproportionally greater than the surrounding areas. Compared to other deep-sea environments, however, the seamounts environment is relatively less explored for fungal diversity. In the present study, we explored the fungal community structure in deep-sea sediments from four different stations of the Magellan seamounts environment by using high-throughput sequencing of the ITS1 region. A total of 1,897,618 ITS1 sequences were obtained. Among these sequences, fungal ITS1 sequences could be clustered into 1,662 OTUs. The majority of these sequences belonged to Ascomycota. In the genera level, the most abundant genus was Mortierella (4.79%), which was reported as a common fungal genus in soil and marine sediments, followed by Umbelopsis (3.80%), Cladosporium (2.98%), Saccharomycopsis (2.53%), Aspergillus (2.42%), Hortaea (2.36%), Saitozyma (2.20%), Trichoderma (2.12%), Penicillium (2.11%), Russula (1.86%), and Verticillium (1.40%). Most of these recovered genera belong to Ascomycota. The Bray-Curtis analysis showed that there was 37 to 85% dissimilarity of fungal communities between each two sediment samples. The Principal coordinates analysis clearly showed variations in the fungal community among different sediment samples. These results suggested that there was a difference in fungal community structures not only among four different sampling stations but also for different layers at the same station. The depth and geographical distance significantly affect the fungal community, and the effect of depth and geographical distance on the structure of the fungal community in the Magellan seamounts is basically same. Most of the fungi were more or less related to plants, these plant parasitic/symbiotic/endophytic fungi constitute a unique type of seamounts environmental fungal ecology, different from other marine ecosystems.

Background The impact of Malassezia yeasts on skin mycobiome and health has received considerable attention recently. Pityriasis versicolor (PV), a common dermatosis caused by Malassezia genus worldwide, is a manifestation of dysbiosis. PV can be associated with hyper- and/or hypopigmented skin lesions. This disease entity is characterized by high percentage of relapses, which demands a proper antifungal therapy that is based on unambiguous species identification and drug susceptibility testing. Case presentation Comprehensive analysis of PV case in man presenting simultaneously hyper- and hypopigmented skin lesions was performed. Conventional and molecular diagnostic procedures revealed Malassezia furfur and Malassezia sympodialis, respectively as etiological agents of skin lesions observed. Susceptibility tests showed significantly lowered sensitivity of M. furfur cells to fluconazole. Based on susceptibility profiles local antifungal therapy with drugs characterized by entirely different mechanism of action was included. Conclusions Our study indicates that cases of PV represented by two types of skin lesions in one patient may be associated with distinct Malassezia species. Moreover, as observed in this case, each of the isolated etiological agents of PV may differ significantly in susceptibility to antifungals. This can significantly complicate the treatment of dermatosis, which by definition is associated with a significant percentage of relapses. In the presented case localized topical treatment was sufficient and successful while allowing maintaining the physiological mycobiome.

Accepted: 2020-08-04, 資料番号: PA2110042000

The Brazilian dry forest (Caatinga) is located in one of the world's largest tropical semiarid regions, and it occurs on two large geological environments named the crystalline and sedimentary basins. In order to determine the structure and the main drivers of the composition of communities of arbuscular mycorrhizal fungi (AMF) in the Caatinga, we collected soil samples from the rhizosphere of Jatropha mollissima, J. mutabilis, and Mimosa tenuiflora, species that occur in crystalline and sedimentary areas. Ninety-six AMF taxa were identified from soils collected directly in the field and trap cultures. Acaulospora, Glomus, and Rhizoglomus represented almost 49% of the taxon richness. The composition of the AMF communities differed between the crystalline and sedimentary areas and between the rhizospheres of the three plant species. Coarse sand, total sand, natural clay, calcium, soil particles density, flocculation, pH, and base saturation were the principal edaphic variables related to the distribution of these organisms. We registered nine and 17 AMF species classified as indicators, for the geological environments and plant species, respectively. Glomerospores of Glomerales predominated in crystalline basins, whereas glomerospores of Gigasporales prevailed in sedimentary areas; among the plant species, lower number of glomerospores of Archaeosporales and Glomerales was recorded in the rhizosphere of J. mollissima. The results show that the AMF community composition is shaped by geological environments and plant hosts. In addition, soil characteristics, mainly physical attributes, significantly influence the structure of Glomeromycota communities occurring in areas of the Brazilian semiarid.

Fungal biological control of soybean cyst nematodes (SCN) is an important component of integrated pest management for soybean. However, very few fungal biological control agents are available in the market. In this study, we have screened fungi previously isolated from SCN cysts over 3 years from a long-term crop rotation field experiment for their ability to antagonize SCN using (i) parasitism, (ii) egg hatch inhibition, and (iii) J2 mortality. We evaluated egg parasitism using an in-vitro egg parasitism bioassays and scored parasitism using the egg parasitic index (EPI) and fluorescent microscopy. The ability of these fungi to produce metabolites causing egg hatch inhibition and J2 mortality was assessed in bioassays using filter-sterilized culture filtrates. We identified 10 high-performing isolates each for egg parasitism and toxicity toward SCN eggs and J2s and repeated the tests after storage for 1 year of cryopreservation at −80°C to validate the durability of biocontrol potential of the chosen 20 isolates. Although the parasitic ability changed slightly for the majority of strains after cryopreservation, they still scored 5/10 on EPI scales. There were no differences in the ability of fungi to produce antinemic metabolites after cryopreservation. [Formula: see text] Copyright © 2020 The Author(s). This is an open access article distributed under the CC BY 4.0 International license .

A phylogenetically diverse array of fungi live within healthy leaf tissue of dicotyledonous plants. Many studies have examined these endophytes within a single plant species and/or at small spatial scales, but landscape-scale variables that determine their community composition are not well understood, either across geographic space, across climatic conditions, or in the context of host plant phylogeny. Here, we evaluate the contributions of these variables to endophyte beta diversity using a survey of foliar endophytic fungi in native Hawaiian dicots sampled across the Hawaiian archipelago. We used Illumina technology to sequence fungal ITS1 amplicons to characterize foliar endophyte communities across five islands and 80 host plant genera. We found that communities of foliar endophytic fungi showed strong geographic structuring between distances of 7 and 36 km. Endophyte community structure was most strongly associated with host plant phylogeny and evapotranspiration, and was also significantly associated with NDVI, elevation and solar radiation. Additionally, our bipartite network analysis revealed that the five islands we sampled each harboured significantly specialized endophyte communities. These results demonstrate how the interaction of factors at large and small spatial and phylogenetic scales shapes fungal symbiont communities.