During nocturnal field expeditions in the Brazilian Atlantic Rainforest, an unexpected bioluminescent fungus with reduced form was found. Based on morphological data, the taxon was first identified as belonging to the cyphelloid genus Maireina, but in our phylogenetic analyses, Maireina was recovered and confirmed as a paraphyletic group related to genera Merismodes and Cyphellopsis. Maireina filipendula, Ma. monacha, and Ma. subsphaerospora are herein transferred to Merismodes. Based upon morphological and molecular characters, the bioluminescent cyphelloid taxon is described as the new genus Eoscyphella, characterized by a vasiform to urceolate basidiomata, subglobose to broadly ellipsoid basidiospores, being pigmented, weakly to densely encrusted external hyphae, regularly bi-spored basidia, unclamped hyphae, and an absence of both conspicuous long external hairs and hymenial cystidia. Phylogenetic analyses based on ITS rDNA and LSU rDNA support the proposal of the new genus and confirm its position in Cyphellopsidaceae. Eoscyphella luciurceolata represents a new lineage of bioluminescent basidiomycetes with reduced forms.

Gymnopilus consists of a widely distributed genus of basidiomycetes, especially in tropical regions of the world, such as Japan, Australia, Paraguay, and Brazil. This genus biosynthesizes interesting bioactive compounds, such as sesquiterpenoids, oligoisoprenoids, styrylpyrones, and lectins. In the present study, the aqueous extract of the basidiomata of Gymnopilus imperialis (Basidiomycota, Agaricomycetes, Agaricales, Hymenogastraceae) was obtained by using the accelerated solvent extraction (ASE) technique, followed by the precipitation of polysaccharide fraction with ethanol. Further purification by freeze-thawing processes, Fehling solution precipitation, and membrane dialysis with different pore sizes yield three main polysaccharide fractions (Gi-MRSW, Gi-PFME, and Gi-SFME). According to monosaccharide composition and ¹³C-NMR data, the Gi-MRSW and Gi-SFME fractions showed to be composed mainly of β-glucans and Gi-PFME by a heterogalactan. Moreover, the immunomodulatory potential of Gi-MRSW was evaluated using RAW 264.7 murine macrophage as a study model. The nitric oxide production was significantly increased in treated samples, and the expression of inducible nitric oxide synthase (iNOS) showed that the fraction Gi-MRSW from G. imperialis induces the M1 polarization phenotype.

The objective of this work was to evaluate the water supply method in the cultivation of button mushroom. The strains used were ABI 18/02, ABI 18/04, ABI 19/03, and ABI 11/19. An analysis of the ITS 1 + 2 regions, widely used as a fungal barcode, was performed in order to assess the genetics. The compost was packed in 35 × 50 cm plastic boxes with 10.5 kg m⁻², and the inoculum was added (1% in relation to the compost weight). Before the addition of the casing layer, in half of the boxes, 25 L m⁻² of water was added directly to the colonized compost, resulting in the treatment of the water added to the compost. The yield, number, and weight of the mushrooms were analyzed. A phylogenetic tree for the A. bisporus strains based on ITS sequences confirms a close genetic relationship among the different collections of this species, and additional molecular markers are required to distinguish genotypes related to superior agronomic traits. The water management methods presented similar yields, except for one strain (ABI 18/04). The ABI 18/02 and 11/019 strains were more efficient when considering the method of adding water to the compost. This study suggests that the treatment of water added to the substrate is an alternative tool for reducing the application time and labor involved and as a control treatment to reduce water use.

It is well-known that bacteria and fungi play important roles in the relationships between mycelium growth and the formation of fruiting bodies. The sun mushroom, Agaricus subrufescens, was discovered in Brazil ca. 1960 and it has become known worldwide due to its medicinal and nutritional properties. This work evaluated the bacterial community present in mushroom-colonized compost extract (MCCE) prepared from cultivation of A. subrufescens, its dynamics with two different soaking times and the influence of the application of those extracts on the casing layer of a new compost block for A. subrufescens cultivation. MCCEs were prepared through initial submersion of the colonized compost for 1 h or 24 h in water followed by application on casing under semi-controlled conditions. Full-length 16S rRNA genes of 1 h and 24 h soaked MCCE were amplified and sequenced using nanopore technology. Proteobacteria, followed by Firmicutes and Planctomycetes, were found to be the most abundant phyla in both the 1 h and 24 h soaked MCCE. A total of 275 different bacterial species were classified from 1 h soaked MCCE samples and 166 species from 24 h soaked MCCE, indicating a decrease in the bacterial diversity with longer soaking time during the preparation of MCCE. The application of 24 h soaked MCCE provided increases of 25% in biological efficiency, 16% in precociousness, 53% in the number of mushrooms and 40% in mushroom weight compared to control. Further investigation is required to determine strategies to enhance the yield and quality of the agronomic traits in commercial mushroom cultivation.

L -DOPA extradiol dioxygenases (DODAs) catalyze the production of betalains and hygroaurins pigments. The sequence of the DODAs found in Caryophyllales and Basidiomycetes are not conserved, although betalains are produced both by plants and fungi. Here we revise the coding region of the dodA gene of fly agaric [ Amanita muscaria (L.) Lam.] and describe an alternative start codon downstream that enables the heterologous expression of AmDODA, a promiscuous l -DOPA dioxygenase. AmDODA is 43-amino acid residues shorter than the recombinant DODA previously reported but catalyzes the formation of two isomeric seco-DOPAs that are the biosynthetic precursors of betalains and hygroaurins. The putative active site of AmDODA contains two distinct His-His-Glu motifs that can explain the dual cleavage of l -DOPA according to the mechanism proposed for non-heme iron-dependent dioxygenases. Upon addition of excess l -DOPA, both the betaxanthin and hygroaurin adducts of l -DOPA are produced. The kinetic parameters of enzymatic catalysis at pH 8.5 are similar to those reported for other l -DOPA dioxygenases. The rate constants for the conversion of l -DOPA into the betalamic acid and muscaflavin were estimated by kinetic modelling allowing the proposal of a mechanism of pigment formation. These results contribute to understanding the biosynthesis of bacterial, fungal and plant pigments, for the biotechnological production of hygroaurins, and for the development of more promiscuous dioxygenases for environmental remediation.