Genetic regulation of L-tryptophan metabolism in Psilocybe mexicana supports psilocybin biosynthesis.
Fungal biology and biotechnology April 25, 2024 Paula Sophie Seibold, Sebastian Dörner, Janis Fricke et al. 8 citations
Psilocybin, a psychedelic alkaloid, can account for up to 2% of the dry mass of Psilocybe mushrooms, creating a high demand for its precursor L-tryptophan during carpophore (fruiting body) formation. Using Psilocybe mexicana, researchers found that genes for L-tryptophan biosynthesis (trpE1, trpD, trpB) were upregulated in carpophores, while genes for L-tryptophan-consuming pathways (idoA, iasA) were massively downregulated. The IasA enzyme was characterized as the first microbial L-tryptophan-preferring acetaldehyde synthase. Comparison with Psilocybe cubensis revealed species-specific differences in regulation. This coordination of primary and secondary metabolism routes L-tryptophan toward psilocybin production, providing initial insight into how Basidiomycota manage metabolic flux.