New Enzyme ApPT Transforms Drug Synthesis for Natural Compounds

Breakthrough Enzyme ApPT Could Revolutionize Drug Development for Complex Compounds

Scientists have uncovered a groundbreaking enzyme that could transform drug development for complex natural compounds. The newly discovered ApPT, a triterpene synthase from Arabidopsis, enables precise chemical modifications to pentacyclic triterpenoids (PTs)—molecules known for their therapeutic potential but notoriously difficult to alter. This advance promises to speed up the creation of optimised drug candidates while reducing reliance on traditional, less sustainable synthesis methods. Pentacyclic triterpenoids (PTs) are bioactive compounds with wide-ranging medical applications, from anti-inflammatory treatments to cancer therapies. However, their intricate polycyclic structures have long made them challenging to modify in the lab. Common pharmaceutical candidates like maslinic acid (in phase II trials for metabolic syndrome), oleanolic acid (tested for liver disease and cancer), and betulinic acid (studied for melanoma and HIV) could now benefit from more efficient production methods.

A research team led by Zhang, Chen, Wang, and collaborators developed a bioinformatics-driven approach to identify **ApPT**, an enzyme capable of selectively hydroxylating aliphatic sites on PTs. Unlike conventional techniques, ApPT achieves high diastereoselectivity, targeting oxidation sites previously considered inaccessible. The discovery was made possible by a specialised pipeline that accelerates the mining of terpene-P450 enzymes, streamlining the search for biocatalysts that can fine-tune complex molecules. The new chemo-enzymatic platform merges biocatalysis with traditional synthesis, enabling the creation of PT derivatives that were once synthetically impractical. By using bacterial cytochrome P450 enzymes, the team demonstrated unprecedented control over C-H bond activation, offering a greener alternative with fewer byproducts and higher atom efficiency. This method is not only scalable but also adaptable to other natural product classes, broadening its potential impact.

The identification of ApPT and its precise oxidation capabilities opens new avenues for drug discovery. Pharmaceuticals based on PTs may now be developed faster, with improved yield, stability, and bioactivity. The bioinformatics-driven strategy also sets a precedent for enzyme discovery, offering a sustainable and transferable model for future research in natural product engineering.