Agaricus crocodilinus (Agaricaceae), an edible saprotrophic mushroom, accumulates high concentrations of cadmium (Cd) in unpolluted environments. This study investigates whether this species has evolved mechanisms to store Cd complexed with metallothioneins (MTs), proteins that bind heavy metal ions via cysteinyl (Cys)-thiolate bonds, how these MTs originated, and how similar mechanisms are present in other fungal species. Size exclusion chromatography revealed that a substantial fraction of Cd in A. crocodilinus sporocarps was sequestered in a 3.4 kDa complex containing Cys-rich peptides. Screening a sporocarp cDNA expression library in a Cd-sensitive Saccharomyces cerevisiae strain identified two MT transcripts, AcMT1 and AcMT2, encoding 49-amino acid (AA) AcMT1 with 10 Cys and 32-AA AcMT2 with 7 Cys. The presence of AcMT2 in the 3.4 kDa Cd-peptide complex isolated from sporocarp was confirmed by mass spectrometry. In mycelial isolates exposed to heavy metals, AcMT1 was more strongly upregulated, while AcMT2 was more expressed under normal conditions. Sequence comparisons revealed that AcMT2 is closer to the ancestral gene, whereas AcMT1 is a more recent duplicate. Combined bioinformatic and functional evidence supports AcMT2 as a constitutively expressed MT involved in Cd binding in the sporocarp, while AcMT1, though more inducible in mycelia and more protective in yeast, appears to serve a transient detoxification role. Moreover, the gene duplication and domain rearrangement mechanism underlying this MT diversification was also identified in other Agaricales and Boletales species.

• Keywords
• Agaricaceae, Gene duplication, Gene internal duplication, Heavy metals,
• Publication type
• Journal Article MeSH

We studied concentrations of 34 essential and non-essential elements in samples of edible Bay Bolete (Imleria badia) mushrooms added by samples of the growing substrate and bioavailable fraction. The samples were collected from six forested sites affected differently by industrial pollution and underlain by compositionally contrasting bedrock: granite, amphibolite, and peridotite. In all cases, mushrooms behaved as a bioconcentrating system for elements such as Ag, K, P, Rb, S, and Se (BCF > 1) being a bioexcluding system for the rest of the elements analyzed (BCF < 1). Most analyzed elements displayed moderate to high within-mushroom mobility being accumulated preferably in the apical parts of the mushroom's fruiting body (TF > 1). The highest mobility was demonstrated by Cd and Cu. Sodium was the only element with significantly low mobility (TF < 1), and it accumulated preferably in the stipe. Imleria badia seems to be sensitive to the accumulation of elements such as As, Cd, and Pb from the atmospheric deposits. Specific geochemistry of the growing substrate was reflected to different extend in the accumulation of elements such as Ag, Cu, Rb, S, Al, Ca, Fe, Ba, and Na in the mushroom's fruiting bodies.

• Keywords
• Bedrock, Mushroom, Soil, Trace elements, Translocation, Uptake,
• MeSH
• Agaricales * chemistry   MeSH
• Environmental Monitoring MeSH
• Trace Elements * analysis   MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Trace Elements * MeSH

We conducted a study of elemental compositions of Xerocomellus chrysenteron samples accompanied by samples of related substrate soils. All samples were collected during the harvesting seasons 2021 and 2022 from three forested sites almost unpolluted by recent human activities and underlain by contrasting bedrock (granite, amphibolite, and serpentinite). Elements such as Ag, Cd, K, P, Rb, S, Se, and Zn were the main elements enriched in the mushroom's fruiting bodies relative to the substrate. Concentrations of most elements in mushrooms were not site-dependent, with only Ag, As, Rb, and Se concentrations significantly depending on the bedrock composition. Some elements analyzed in mushrooms displayed temporal features, but such features were not systematic and varied for each element. Most analyzed elements were distributed unevenly within the mushroom's fruiting bodies, with apical parts generally enriched in mobile elements. Mushrooms influenced concentrations of Ag, Cd, K, and Rb and a few other elements in the substrate via uptake, but such influence was very limited and can be responsible for only 2.5-11.5% of total depletion of the affected substrate in the named elements.

• Keywords
• Bedrock, Mushroom, Soil, Trace elements, Translocation, Uptake,
• MeSH
• Agaricales * MeSH
• Basidiomycota * MeSH
• Cadmium MeSH
• Humans MeSH
• Environmental Monitoring MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Cadmium MeSH

Since not only psilocybin (PSB) but also PSB-containing mushrooms are used for psychedelic therapy and microdosing, it is necessary to know their concentration variability in wild-grown mushrooms. This article aimed to determine the PSB, psilocin (PS), baeocystin (BA), norbaeocystin (NB), and aeruginascin (AE) concentrations in a large sample set of mushrooms belonging to genera previously reported to contain psychotropic tryptamines. Ultra-high performance liquid chromatography coupled with tandem mass spectrometry was used to quantify tryptamine alkaloids in the mushroom samples. Most mushroom collections were documented by fungarium specimens and/or ITS rDNA/LSU/EF1-α sequencing. Concentrations of five tryptamine alkaloids were determined in a large sample set of 226 fruiting bodies of 82 individual collections from seven mushroom genera. For many mushroom species, concentrations of BA, NB, and AE are reported for the first time. The highest PSB/PS concentrations were found in Psilocybe species, but no tryptamines were detected in the P. fuscofulva and P. fimetaria collections. The tryptamine concentrations in mushrooms are extremely variable, representing a problem for mushroom consumers due to the apparent risk of overdose. The varied cocktail of tryptamines in wild mushrooms could influence the medicinal effect compared to therapy with chemically pure PSB, posing a serious problem for data interpretation.

• Keywords
• Psilocybe, baeocystin, hallucinogenic fungi, psilocin, psilocybin,
• MeSH
• Agaricales * genetics   chemistry   MeSH
• Alkaloids * analysis   MeSH
• Tryptamines MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Alkaloids * MeSH
• baeocystin MeSH Browser
• N, N, N-trimethyl-4-phosphoryloxytryptamine MeSH Browser
• tryptamine MeSH Browser
• Tryptamines MeSH