Fuller JL, Shi K, Pockes S, Finzel BC, Ashe KH, Walters MA. Reengineering of Circularly Permuted Caspase-2 to Enhance Enzyme Stability and Enable Crystallographic Studies. ACS Chemical Biology. 2025;20(4):845-857. PMID: 40117490. DOI: 10.1021/acschembio.4c00795.
Summary
This structural biology study addressed a major technical barrier in caspase-2 drug discovery: poor protein behavior for crystallography. The authors engineered circularly permuted caspase-2 variants to improve expression, stability, and crystallization. One mutant, JF1cpCasp2, enabled crystal structures with both the canonical inhibitor AcVDVAD-CHO and a caspase-2-selective inhibitor. These structures revealed interactions useful for structure-based inhibitor design and created a platform for future medicinal chemistry optimization.
Key Findings
- Circularly permuted caspase-2 variants improved protein behavior.
- JF1cpCasp2 showed enhanced stability and crystallizability.
- Crystal structures were obtained with key inhibitors.
- Structural information revealed interactions relevant to selectivity.
Impact on the Caspase-2/Tau Program
This paper enabled structure-guided caspase-2 drug discovery. It provides the structural platform needed to optimize potency, selectivity, and drug-like properties.