Selective Phosphorylation of Phenols and Benzenediols by the Kinase PsiK and Variants Thereof
Ahram Kim, Nicolás M. Morato, Prabir Saha, Pascal N. Eyimegwu, Aqeel A. Niyaz, Rui Huang, R. Graham Cooks, Ryan M. Phelan, Jared C. Lewis
Angewandte Chemie International Edition June 17, 2025 DOI: 10.1002/anie.202503538 via OpenAlex
Summary
The enzyme PsiK, which selectively phosphorylates psilocin during psilocybin biosynthesis in Psilocybe cubensis, can also phosphorylate a wide range of substituted phenols and benzenediols beyond its natural substrate. This expands the scope of biocatalytic phosphorylation for synthetic chemistry. Active site mutations further broaden substrate scope and improve site-selectivity, with engineering expedited by DESI-MS screening that analyzed 2688 reactions in 40 minutes. Gram-scale phosphorylation of a representative substrate achieved a turnover number over 10,000. These results highlight PsiK's utility for selective phosphorylation under mild conditions.
Study at a glance
| Characteristics | Experimental study Peer reviewed |
|---|---|
| Keywords | Substrate aquarium Kinase Selectivity Enzyme Phenols |
| Citations | 4 |
| Key finding | PsiK has good activity on a range of substituted phenols and benzenediols beyond its native substrate, enabling preparative phosphorylation and substantially expanding the substrate scope of biocatalytic phosphorylation. |
Abstract
Phosphorylation plays important roles in biology by modulating the structure, reactivity, and biological function of a broad range of molecules. Biocatalytic phosphorylation has attracted attention from synthetic chemists due to its selectivity and mild reaction conditions using ATP as a phosphate donor. Given the potential synthetic utility of kinases with activity on small molecule substrates, we explored the activity of PsiK, the enzyme responsible for selective 4-O-phosphorylation of 4-hydroxytryptamine or psilocin in psylocybin biosynthesis by Psilocybe cubensis. We find that PsiK has good activity on a range of substituted phenols and benzenediols beyond its native substrate, enabling preparative phosphorylation of different substrates, and substantially expands the substrate scope of biocatalytic phosphorylation. We also show that active site mutations can further expand substrate scope and improve site-selectivity. This engineering effort was greatly expedited using DESI-MS screening, which enabled analysis of 2688 reactions in only 40 min. Finally, gram-scale phosphorylation of a representative substrate was achieved with a turnover number over 10 000. Together, these results highlight the biocatalytic utility of PsiK and derivatives thereof for selective phosphorylation of phenols and benzenediols under mild conditions.