Masked cerulenin enables a dual-site selective protein crosslink

Protein-reactive natural products such as the fungal metabolite cerulenin are recognized for their value as therapeutic candidates, due to their ability to selectively react with catalytic residues within a protein active site or a complex of protein domains. Here, we explore the development of fatty-acid and polyketide-synthase probes by synthetically modulating cerulenin's functional moieties. Using a mechanism-based approach, we reveal unique reactivity within cerulenin and adapt it for fluorescent labeling and crosslinking of fatty-acid and iterative type-I polyketide synthases. We also describe two new classes of silylcyanohydrin and silylhemiaminal masked crosslinking probes that serve as new tools for activity and structure studies of these biosynthetic pathways. Translation of the natural product cerulenin into probe for fluorescent labeling and masked crosslinker to evaluate protein-protein interactivity.

Automated summary

This study developed a probe based on the natural product cerulenin for fluorescent labeling and crosslinking to evaluate protein-protein interactions. Additionally, two new masked crosslinking probes were described for activity and structure studies of biosynthetic pathways.