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Psychoactive mushrooms in the genusPsilocybehave immense cultural value and have been used for centuries in Mesoamerica. Despite the recent surge of interest in these mushrooms due to the psychotherapeutic potential of their natural alkaloid psilocybin, their phylogeny and taxonomy remain substantially incomplete. Moreover, the recent elucidation of the psilocybin biosynthetic gene cluster is known for only five of ~165 species ofPsilocybe, four of which belong to only one of two major clades. We set out to improve the phylogeny ofPsilocybeusing shotgun sequencing of fungarium specimens, from which we obtained 71 metagenomes including from 23 types, and conducting phylogenomic analysis of 2,983 single-copy gene families to generate a fully supported phylogeny. Molecular clock analysis suggests the stem lineage ofPsilocybearose ~67 mya and diversified ~56 mya. We also show that psilocybin biosynthesis first arose inPsilocybe, with 4 to 5 possible horizontal transfers to other mushrooms between 40 and 9 mya. Moreover, predicted orthologs of the psilocybin biosynthetic genes revealed two distinct gene orders within the biosynthetic gene cluster that corresponds to a deep split within the genus, possibly a signature of two independent acquisitions of the cluster withinPsilocybe.
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Discovery of the Azaserine Biosynthetic Pathway Uncovers a Biological Route for α‐Diazoester Production
Abstract Azaserine is a bacterial metabolite containing a biologically unusual and synthetically enabling α‐diazoester functional group. Herein, we report the discovery of the azaserine (aza) biosynthetic gene cluster fromGlycomyces harbinensis. Discovery of related gene clusters reveals previously unappreciated azaserine producers, and heterologous expression of theazagene cluster confirms its role in azaserine assembly. Notably, this gene cluster encodes homologues of hydrazonoacetic acid (HYAA)‐producing enzymes, implicating HYAA in α‐diazoester biosynthesis. Isotope feeding and biochemical experiments support this hypothesis. These discoveries indicate that a 2‐electron oxidation of a hydrazonoacetyl intermediate is required for α‐diazoester formation, constituting a distinct logic for diazo biosynthesis. Uncovering this biological route for α‐diazoester synthesis now enables the production of a highly versatile carbene precursor in cells, facilitating approaches for engineering complete carbene‐mediated biosynthetic transformations in vivo.
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- Award ID(s):
- 2027943
- PAR ID:
- 10417554
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 62
- Issue:
- 28
- ISSN:
- 1433-7851
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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