AI & ML Practical Magic

We've moved from drugs that block disease to 'designer proteins' that act as cellular garbage trucks to destroy them.

April 16, 2026

Original Paper

De novo designed bifunctional proteins for targeted protein degradation

Mylemans, B.; Korona, B.; Acevedo-Jake, A. M.; MacRae, A.; Edwards, T. A.; Huang, D. T.; Wilson, A. J.; Itzhaki, L. S.; Woolfson, D. N.

bioRxiv · 10.64898/2025.12.22.695915

The Takeaway

Computational protein design has achieved a breakthrough: entirely new, bifunctional proteins that can seek out and destroy specific disease-linked proteins (like BCL-xL). Unlike traditional drugs that just inhibit a protein's function, these new designs physically escort the target to the cell's waste-disposal system. This 'targeted degradation' approach is significantly more effective and harder for diseases to build resistance against. It turns drug discovery into a high-precision engineering task. For the biotech industry, this unlocks the ability to target 'undruggable' proteins that were previously out of reach for small molecules. It is a fundamental shift from chemical medicine to biological engineering.

From the abstract

Targeted protein degradation (TPD) is a therapeutic strategy to remove disease-causing proteins by routing them to the ubiquitin-proteasome, autophagy, or lysosme machineries. For instance, proteolysis-targeting chimeras (PROTACs) are synthetic hetero-bifunctional small molecules that simultaneously bind the target and an E3 ubiquitin ligase to drive ubiquitination and degradation by the proteasome. Despite considerable success, designing such molecules is challenging and the number of currently