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Neurospora growing on the trunk of a burned tree. Colonies of conidiating Neurospora are easily spotted by their orange color due to the accumulation of carotenoid pigments. The picture was taken in a garden in Seville (Spain) a few weeks after a summer fire in 2004 and is probably Neurospora crassa as all the samples taken from this site were later identified as belonging to this species. doi:10.1371/journal.pone.0033658.g001
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The ascomycete fungus Neurospora is present in many parts of the world, in particular in tropical and subtropical areas, where it is found growing on recently burned vegetation. We have sampled the Neurospora population across Spain. The sampling sites were located in the region of Galicia (northwestern corner of the Iberian peninsula), the provinc...
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... ascomycete fungus Neurospora crassa is used as a model organism for research on different aspects of eukaryotic molecular biology including RNA inactivation and gene silencing, the mechanism of genetic recombination, regulation by the circadian clock, and the regulation by light of gene expression [1–4]. In addition, a collection of more than 4000 Neurospora wild-type strains from natural populations has provided information about the distribution of the different species of Neurospora in the world [5,6]. Genomic analysis of wild-type strains of Neurospora has allowed detailed characterization of the process of adaptation to local environmental conditions [7]. Most of the Neurospora species have been identified in tropical or subtropical areas where they can be easily spotted growing on the surface of recently burned vegetation. Extensive surveys have extended the geographical distribution of Neurospora to temperate areas of western North America and Europe, with colonies of N. discreta identified as far north as Alaska [8,9]. The distribution of Neurospora species in nature is varied. For example, N. discreta is the most frequent Neurospora species isolated in western North America [8] but in Europe N. discreta was rarely found while N. crassa , N. sitophila , and N. tetrasperma were frequently observed [9]. The colonies of Neurospora are very conspicuous due to the accumulation of the orange carotenoid neurosporaxanthin in conidia and vegetative mycelia [10]. The biosynthesis of neurosporaxanthin in vegetative mycelia is induced by light [11] through the activation of the biosynthetic genes [12,13]. Light serves as an environmental cue to adjust the circadian clock so that Neurospora can anticipate changes in environmental conditions [12,14–16]. Carotenoids, like neurosporaxanthin, are antioxidants due to their capacity to quench reactive oxygen species [17–19], and provide protection against UV damage in human skin [20] and fungi [21–23], but not against gamma-radiation in the fungus Phycomyces blakesleeanus [24]. Pigmented strains of the basidiomy- cetous yeast Sporobolomyces ruberrimus and Cystofilobasidium capitatum were more tolerant to UV damage and showed better survival after UV treatment than unpigmented strains [21]. The accumulation of carotenoids protected the yeast Rhodotorula mucilaginosa from UV damage [23]. In animals, a photoprotective role for carotenes in echinoids eggs has been suggested [25], and mice fed with beta-carotene or canthaxanthin were protected against skin tumors caused by UV radiation [26]. Carotenoids provide protection against excess irradiation in photosynthetic organisms. For example, accumulation of carotenoids (beta- carotene, zeaxanthin, or canthaxanthin) in strains of the cyanobacterium Synechococcus after transformation with carotenogenic genes led to protection of photosynthesis from UV damage [27,28]. The activation by light of carotenoid biosynthesis in Neurospora and other fungi [29] may optimize protection against UV radiation when the fungus is growing exposed to light in open environments. Tropical regions (low latitude) receive more solar radiation than northern locations (high latitude). For a given site the amount of solar radiation changes during the time of the year, the altitude and the atmospheric conditions, but during the summer low-latitude locations receive twice the amount of UV-B radiation (280–315 nm) than high-latitude locations [30,31]. It is possible that the capability to accumulate carotenoids may affect the distribution of Neurospora species in low-latitude areas due to a high exposure to UV radiation. The region of Galicia (northwestern corner of the Iberian peninsula) and the two major islands of the Canary Islands archipelago (Tenerife and Gran Canaria, west coast of Africa) suffered an unusual number of wildfires during the summers of 2006 and 2007 respectively. Since Neurospora is easily spotted on burned vegetation, these summer fires allowed the opportunity to sample the Neurospora populations in these separated areas. We have observed differences in the distribution of Neurospora species in each site. The four Neurospora species that we have identified ( N. discreta , N. crassa , N. tetrasperma , and N. sitophila ) showed differences in the accumulation of carotenoids after light exposure. In addition, we have found a correlation between the accumulation of carotenoids in Neurospora and the latitude of the sampling site. Our results suggest that the capability to accumulate carotenoids plays a role in the distribution of Neurospora species in nature. Colonies of Neurospora were readily observed growing on the surface of partially burned vegetation (Fig. 1), as already observed previously in other European collection sites [9]. We collected Neurospora wild-type strains from eight sites located in the region of Galicia and from one site in the province of C ́ceres (summer of 2006), and from six sites in the Canary Island archipelago (summer of 2007) that included samples from the two major islands (Tenerife and Gran Canaria). The sites were selected by their accessibility to locations where wild fires had occurred recently (4– 6 weeks). The sites that we selected may not be representatives of the entire region. The location of the collection sites had latitudes that ranged from 27.88 u N (Fataga and Mor ́n, Las Palmas) to 42.74 u N (Herb ́n, A Coru ̃ a). In 41 plants we took more than one sample in order to investigate the presence of genetic variations in the Neurospora strains that colonized a single plant. The samples were collected, purified from single colonies, and stored prior to further characterization. From the samples that we isolated in the field trips we purified and stored a total of 125 wild-type strains (Table S1). Our collection also includes 26 Neurospora crassa strains isolated from Seville in 2004 that have been reported previously [9]. We used a phylogenetic method to identify the species of each collected Neurospora strain. We amplified and sequenced three unlinked polymorphic loci (TMI, TML, and DMG) from each wild-type strain [32]. These loci have been used successfully to infer the evolution and diversity of species of the genus Neurospora [32–35]. The sequences from the three loci from each strain were combined and aligned with homologous sequences from a set of reference Neurospora strains [32,35]. The resulting DNA alignment was used to reconstruct a phylogenetic tree by the Maximum- Likelihood and Neighbor-Joining methods (Fig. 2). The Neurospora species for each isolate was deduced by the presence of a reference Neurospora species close to each unknown strain in the phylogenetic tree. A group of isolates formed a clade with different N. crassa reference strains and were assigned to N. crassa . The Spanish N. crassa formed a clade with a reference N. crassa strain from clade B as previous European N. crassa isolates [9]. Similarly, a group of isolates formed a clade with reference N. discreta strains and were assigned as N. discreta . Finally, one strain (GC4-5C) formed a clade with N. sitophila and was assigned as a N. sitophila (Fig. 2). Some strains could not be assigned using the phylogenetic method. Three isolates (C9C, OU12C, and C6A) formed a well- defined clade that separated before the major clade that included all the N. discreta reference strains (Fig. 2). These strains were classified as N. discreta but they may represent a new phylogenetic species. In addition, a group of strains formed a clade that included N. tetrasperma , and N. hispaniola (Fig. 2). As an alternative method to identify the Neurospora species corresponding to these strains we performed blast searches using DNA sequences for the TMI, TML, and DMG loci from each strain. Searches of the Neurospora DNA database with sequences from DMG and TML from strains C9C, OU12C, and C6A identified N. discreta DNAs as the most similar sequences, thus confirming these strains as N. discreta . Searches using TMI identified a variety of different Neurospora species and were not considered. Searches using the three loci from the group of putative N. tetrasperma strains were not conclusive as they identified a variety of different Neurospora species. We therefore amplified and sequenced a fourth locus (QMA) [32] from these strains. Blast searches using QMA sequences from these strains identified N. tetrasperma DNA in the Neurospora DNA database and supported the assignment of these strains as N. tetrasperma . In addition, these strains produced Neurospora sexual structures, perithecia, when grown in independent cultures. Matured perithecia contained asci with four ascospores, and the strains developed asexual conidia (not shown) and accumulated carotenoids (see below). These biological properties are specific for N. tetrasperma , a self fertile species that can reproduce in isolation due to the presence of nuclei with either mating type in the same hyphae (pseudohomothalism) [5]. The biological properties of these strains, and the similarities of their QMA locus with N. tetrasperma DNA supported our assignment of these strains as N. tetrasperma . Further characterization of the Neurospora wild-type strains by phylogenetic species recognition (PSR) [36] confirmed the Neurospora species assigned to each strain, with the exception of the N. tetrasperma strains. We have identified 64 N. discreta strains, 17 N. tetrasperma strains, 69 N. crassa strains, and one N. sitophila strain (Table 1, Table S1). These heterothallic and pseudohomothallic species appear as a terminal clade in the phylogeny of the genus Neurospora [37]. The distribution of Neurospora ...
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Citations
... Carotenoids are pigments whose primary function is to protect cells and tissues against oxidative processes (Stahl and Sies, 2003). These pigments have already been described in entomopathogenic fungi for their role in the environmental detoxification of oxidative molecules in insect tissues during fungal colonization (Luque et al., 2012;Zhang et al., 2016;Wang and St. Leger, 2007). The carotenoid 19'-H is derived from xanthine, a metabolite detected in our in vitro cultured consortium (Stuart et al., 2022). ...
One of the most concerning pests that attack strawberries in Brazil is Duponchelia fovealis (Zeller), a non-native moth with no registered control methods to date. Our group recently observed that a fungal consortium formed by two strains of Beauveria bassiana (Balsamo) increased the mortality of D. fovealis more than inoculation with each strain on its own. However, the molecular interaction between the fungal consortium and the caterpillars is unknown. Thus, in this work, we sought to pioneer the evaluation of the molecular interaction between a fungal consortium of B. bassiana and D. fovealis caterpillars. We aimed to understand the biocontrol process involved in this interaction and the defense system of the caterpillar. Seven days after D. fovealis were inoculated with the consortium, the dead and surviving caterpillars were analyzed using GC-MS and LC-MS. Some of the metabolites identified in dead caterpillars have primarily antioxidant action. Other metabolites may have insecticidal potential, such as diltiazem-like and tamsulosin-like compounds, as well as 2,5-dimethoxymandelic acid. In surviving caterpillars, the main mechanisms are pro-inflammatory from 2-Palmitoylglycerol metabolite and the antifungal action of the metabolite Aegle marmelos Alkaloid-C. The metabolites identified in dead caterpillars may explain the increased mortality caused by the consortium due to its antioxidant mechanism, which can suppress the caterpillars' immune system, and insecticide action. In surviving caterpillars, the main resistance mechanisms may involve the stimulus to the immunity and antifungal action.
... Short exposure times, for example 5 s, activate transcription of the conidiation genes con-10 and con-6, but maximum mRNA accumulation was observed after 45 min of further incubation in the dark [50]. It is possible that light-dependent transcription and translation is not sufficient as a response to sudden changes in light exposure or intensities in natural habitats, such as the surface of burned trees where conidiating mycelia of Neurospora species are often observed [51,52]. We can hypothesize that the regulation by light of VE-1 degradation could be a novel mechanism that ensures the presence of VE-1 for further transcriptional regulation during the development of conidia after sudden exposures to light. ...
Background
Fungi use light as an environmental signal to regulate developmental transitions that are key aspects of their biological cycles and that are also relevant for their dispersal and infectivity as plant or animal pathogens. In addition, light regulates the accumulation of photoprotective pigments, like carotenoids, and other secondary metabolites. Most fungal light responses occur after changes in gene transcription and we describe here a novel effect of light in the regulation of degradation of VE-1, a key component of the velvet complex, in the model fungus Neurospora crassa. The velvet complex is a fungal-specific protein complex that coordinates fungal development, secondary metabolism, and light regulation by interacting with other regulators and photoreceptors and modifying gene expression.
Results
We have characterized the role of VE-1 during conidiation in N. crassa. In vegetative mycelia, VE-1 is localized in the cytoplasm and nuclei and is required for light-dependent transcription but does not interact with the photoreceptor and transcription factor WC-1. VE-1 is more stable in light than in darkness during asexual development (conidiation). We have shown that this light effect requires the blue-light photoreceptor WC-1. We have characterized the role of the proteasome, the COP9 signalosome (CSN), and the adaptor component of cullin-RING ubiquitin ligases, FWD-1, in the degradation of VE-1.
Conclusions
We propose that this new effect of light allows the fungal cell to adapt quickly to changes in light exposure by promoting the accumulation of VE-1 for the regulation of genes that participate in the biosynthesis of photoprotective pigments.
... This repeated observation of fruiting on burned material suggests some capacity for using unique compounds produced through combustion, a post-fire nutrient acquisition trait as outlined in Figure 7, and was recently explored in a study on Pyronema domesticum charcoal metabolysis (Fischer et al., 2021). It is also possible that their colour or morphology makes them better adapted to post-fire scenarios; for example, many of them are orange and contain carotenoids (Carlile & Friend, 1956) which may add UV protection (Luque et al., 2012). ...
Mega‐fires of unprecedented size, intensity, and socio‐economic impacts have surged globally due to climate change, fire suppression, and development. Soil microbiomes are critical for post‐fire plant regeneration and nutrient cycling, yet how mega‐fires impact the soil microbiome remains unclear. We had a serendipitous opportunity to obtain pre‐ and post‐fire soils from the same sampling locations after the 2016 Soberanes mega‐fire burned with high severity throughout several of our established redwood‐tanoak plots. This makes our study the first to examine microbial fire response in redwood‐tanoak forests. We re‐sampled soils immediately post‐fire from two burned plots and one unburned plot to elucidate the effect of mega‐fire on soil microbiomes. We used Illumina MiSeq sequencing of 16S and ITS1 to determine that bacterial and fungal richness were reduced by 38‐70% in burned plots, with richness unchanged in the unburned plot. Fire altered composition by 27% for bacteria and 24% for fungi, whereas the unburned plots experienced no change in fungal and negligible change in bacterial composition. We observed pyrophilous taxa that positively responded to fire were phylogenetically conserved, suggesting shared evolutionary traits. For bacteria, fire selected for increased Firmicutes and Actinobacteria. For fungi, fire selected for the Ascomycota classes Pezizomycetes and Eurotiomycetes and for a Basidiomycota class of heat‐resistant Geminibasidiomycete yeasts. We build from Grime’s Competitor‐Stress tolerator‐Ruderal (C‐S‐R) framework and its recent microbial applications to show how our results might fit into a trait‐based conceptual model to help predict generalizable microbial responses to fire.
... For example, fungi isolated closer to the equator also tended to be more UV-B tolerant, likely due to selection pressures in their environment (Braga et al., 2001). In other investigations of UV tolerance, Neurospora strains from lower latitudes accumulated more carotenoids for photoprotection (Luque et al., 2012). Beyond strict latitudinal comparison, researchers also found that isolates of Cocciodes posadasii were generally more thermotolerant than isolates of Cocciodes immitis, an observation consistent with the fact that C. posadasii is endemic to the warmer Sonoran Desert while C. immitis is endemic to the cooler Central Valley (Mead et al., 2020). ...
Understanding the how behind the polyphyletic trait of fungal thermotolerance has important implications to both medical and industrial pursuits. In this review, our goal is to synthesize research on fungal thermotolerance from industry, biology, and health science to provide an overview of where the field stands. We first consider correlative traits, which may not directly cause thermotolerance but have demonstrated strong associations with it. We then look into the biomolecules involved in sensing and responding to heat shock and/or stress. Lastly, we examine an overview of physiological mechanisms, both natural and man-made, which fungi can use to withstand heat stress both in the moment and among their progeny. Each section makes attempts to list relevant applications of various traits, in addition to potential knowledge gaps that will need to be addressed in future research. This review highlights that, although thermotolerance is a complex concept with diverse manifestations throughout the fungal kingdom, there are multiple patterns in the heat-shock response worthy of further study.
... Carotenoid accumulation in Neurospora strains is related to latitude and UV radiation, with higher levels at higher latitudes, correlated with increased UV. Moreover in this organism, carotenoid accumulation is associated with UV-resistance (Luque et al., 2012). For several fungi it has been reported that production of carotenoids is induced in a WC-1 dependent manner (Fuller et al., 2015). ...
Ultraviolet (UV) radiation directly affects plants and microorganisms, but also alters the species-specific interactions between them. The distinct bands of UV radiation, UV-A, UV-B, and UV-C have different effects on plants and their associated microorganisms. While UV-A and UV-B mainly affect morphogenesis and phototropism, UV-B and UV-C strongly trigger secondary metabolite production. Short wave (<350 nm) UV radiation negatively affects plant pathogens in direct and indirect ways. Direct effects can be ascribed to DNA damage, protein polymerization, enzyme inactivation and increased cell membrane permeability. UV-C is the most energetic radiation and is thus more effective at lower doses to kill microorganisms, but by consequence also often causes plant damage. Indirect effects can be ascribed to UV-B specific pathways such as the UVR8-dependent upregulated defense responses in plants, UV-B and UV-C upregulated ROS accumulation, and secondary metabolite production such as phenolic compounds. In this review, we summarize the physiological and molecular effects of UV radiation on plants, microorganisms and their interactions. Considerations for the use of UV radiation to control microorganisms, pathogenic as well as non-pathogenic, are listed. Effects can be indirect by increasing specialized metabolites with plant pre-treatment, or by directly affecting microorganisms.
... Thus, about 0.1-0.2 mg/g of a NX-containing carotenoid mixture are found in mycelia grown under light in F. fujikuroi [23], N. crassa [44] and P. anserina [45]. In the case of N. crassa, carotenoids are accumulated in higher amounts in their conidia [46], providing a typical intense orange Figure 5A. ...
... Thus, about 0.1-0.2 mg/g of a NX-containing carotenoid mixture are found in mycelia grown under light in F. fujikuroi [23], N. crassa [44] and P. anserina [45]. In the case of N. crassa, carotenoids are accumulated in higher amounts in their conidia [46], providing a typical intense orange pigmentation to their aerial cultures. ...
Neurosporaxanthin (NX) is a carboxylic carotenoid produced by some filamentous fungi, including species of the genera Neurospora and Fusarium. NX biosynthetic genes and their regulation have been thoroughly investigated in Fusarium fujikuroi, an industrial fungus used for gibberellin production. In this species, carotenoid-overproducing mutants, affected in the regulatory gene carS, exhibit an upregulated expression of the NX pathway. Based on former data on a stimulatory effect of nitrogen starvation on carotenoid biosynthesis, we developed culture conditions with carS mutants allowing the production of deep-pigmented mycelia. With this method, we obtained samples with ca. 8 mg NX/g dry mass, in turn the highest concentration for this carotenoid described so far. NX-rich extracts obtained from these samples were used in parallel with carS-complemented NX-poor extracts obtained under the same conditions, to check the antioxidant properties of this carotenoid in in vitro assays. NX-rich extracts exhibited higher antioxidant capacity than NX-poor extracts, either when considering their quenching activity against [O2(1 ∆g)] in organic solvent (singlet oxygen absorption capacity (SOAC) assays) or their scavenging activity against different free radicals in aqueous solution and in liposomes. These results make NX a promising carotenoid as a possible feed or food additive, and encourage further studies on its chemical properties.
... In addition, the genus Neurospora has been reported to be particularly suitable in a variety of genetic, biochemical, developmental and subcellular genetic engineering studies [28,29,30]. N. sitophila is also being used in modern biotechnology [31], e.g. for the production of microbial phytase [32] or for the production of carotenoids [33,34,35]. However, doubts about its pathogenicity still remain. ...
Neurospora sitophila is a microscopic filamentous fungus of the Ascomycete taxon that rapidly expands in the environment. Although the fungus has been recorded primarily as a known laboratory contaminant, this contribution presents evidence of its frequent occurrence in indoor environment of offices at the university, especially in places where a coffee maker was part of the equipment. A total of 50 smears were made from the environment of the University of VŠB - TU Ostrava from various parts of the fixtures. It was found that spores and fragments of N. sitophila mycelia are an active part of the building air using the BIOLOG identification system. Although no direct evidence has yet been obtained that N. sitophila is the causative agent of human disease or infection, the presence of this fungus in the environment should be regarded as a risk factor for human health. Exposure to fungal spores and fragments of mycelia in the indoor environment of buildings can cause hypersensitivity known to be an influencing factor in allergic reactions and asthma.
... The initial objective of the systematic sampling initiative set up by Perkins was to provide genetic variants for laboratory investigations. Although the mode of primary colonization of Neurospora and other fundamental aspects of the ecology of these organisms remain a particular mystery, a distinctive advantage of Neurospora relative to many microbes was the relative ease of sampling in diverse ecosystems [2,16]. Perkins, Dave Jacobson and other scholars eventually gathered a collection of >5000 isolates, access to which is still provided by the Fungal Genetics Stock Center (University of Kansas). ...
... More generally, studies on wild Neurospora isolates have shown that fungal species are highly structured and that fungal distribution have been shaped by geological and climatic events the same way as macrobes have [34,35]. Conventional criteria based on morphology are of little use to ascertain taxonomic status in Neurospora as most conidiating species cannot be distinguished from one another by the size, color and shape of their vegetative and reproductive organs [9,16,17]. Hence, by morphological species recognition, only two species of conidiating Neurospora are found: one with eight ascospores per ascus, and one with four ascospores per ascus (see Note 1). The two morphospecies are both cosmopolitan in temperate and tropical latitudes (Table 1). ...
... In vitro mating compatibility tests and phylogenetic analyses, however, reveal that the two morphological species have their own biogeography and encompass multiple endemic species: under biological species recognition seven species are found, while under phylogenetic species recognition at least twenty-six species are identified (Table 1). Similar to many plant [16,24] N. crassa N. perkinsii Western Tropical Africa [29,30] N. crassa Western Europe, South Asia, Gulf of Mexico, Western Tropical Africa [16,24,29,30] N. intermedia N. intermedia South and Southeast Asia, Polynesia, Western Tropical Africa, Gulf of Mexico [29,30] N. hispaniola N. hispaniola Hispaniola [29,30] N. metzenbergii N. metzenbergii Madagascar, Gulf of Mexico [29,30] N. discreta N. discreta sensu stricto Gulf of Mexico [31] N. discreta PS4 Western Europe, North America, Papua New Guinea, Western tropical Africa [16,24,31] N. discreta PS5, PS6, PS8 ...
The ascomycete filamentous fungus Neurospora crassa played a historic role in experimental biology and became a model system for genetic research. Stimulated by a systematic effort to collect wild strains initiated by Stanford geneticist David Perkins, the genus Neurospora has also become a basic model for the study of evolutionary processes, speciation, and population biology. In this chapter, we will first trace the history that brought Neurospora into the era of population genomics. We will then cover the major contributions of population genomic investigations using Neurospora to our understanding of microbial biogeography and speciation, and review recent work using population genomics and genome-wide association mapping that illustrates the unique potential of Neurospora as a model for identifying the genetic basis of (potentially adaptive) phenotypes in filamentous fungi. The advent of population genomics has contributed to firmly establish Neurospora as a complete model system and we hope our review will entice biologists to include Neurospora in their research.
... Neurospora crassa is an ascomycete heterothallic filamentous fungus that grows as branched multinucleated hyphae with perforated septa. In nature, species of Neurospora have been found in a wide range or areas that include tropical, subtropical and temperate regions, and the fungus is easily detected growing on the surface of fire-scorched vegetation because of its ability to metabolize cellulose and the activation by heat of the sexual spores (ascospores) (Jacobson et al. 2006;Jacobson et al. 2004;Luque et al. 2012;Turner et al. 2001). N. crassa has been used as a model organism for the research on several aspects of eukaryotic biology, including the mechanism of recombination, genome defence by RNAi, circadian clock regulation and light sensing (Davis and Perkins 2002;Perkins and Davis 2000;Roche et al. 2014) The life cycle of N. crassa includes asexual reproduction and the development of vegetative conidia that are easy to disperse. ...
Asexual development, conidiation, in the filamentous fungus Neurospora crassa is a simple developmental process that starts with the growth of aerial hyphae. Then, the formation of constrictions and subsequent maturation gives rise to the mature conidia that are easily dispersed by air currents. Conidiation is regulated by environmental factors such as light, aeration and nutrient limitation, and by the circadian clock. Different regulatory proteins acting at different stages of conidiation have been described. The role of transcription factors such as FL, and components of signal transduction pathways such as the cAMP phosphodiesterase ACON-2 suggest a complex interplay between differential transcription and signal transduction pathways. Comparisons between the molecular basis of conidiation in N. crassa and other filamentous fungi will help to identify common regulatory elements.
... During the stationary growth phase, high levels of carotenoids have been shown to enhance the chances of survival. Indeed, Neurospora crassa, which displays high levels of carotenoids, was more tolerant to UV radiation than Neurospora discreta or Neurospora tetrasperma, species containing low pigment content (25). ...
Our study shows the morphological and chemical responses of S. himantioides to controlled doses of UV-B radiation under in vitro culture conditions. We found that increased biosynthesis of xerocomic acid was the main strategy adopted by S. himantioides against UV-B radiation. Xerocomic acid showed strong antioxidant and photoprotective abilities, which has not previously been reported. Our results indicate that upon UV-B exposure, S. himantioides decreases its hyphal growth rate and uses this energy instead to increase the biosynthesis of xerocomic acid, which is allocated near the cell wall. This metabolic switch likely allows xerocomic acid to efficiently defend S. himantioides from UV radiation through its antioxidant and photoprotective properties. The findings further suggest that xerocomic acid is a promising candidate for development as a cosmetic ingredient to protect against UV radiation and should therefore be investigated in depth in the near future both in vitro and in vivo .
