Minhaj Shaikh, Surya P Mookherjee, Claire Weckerly, Adam H Libby, Aizhen Xiao, Yunge Zhao, Sagar D Vaidya, AeRyon Kim, Zhihong Li, Madeleine L Ware, Michelle Marants, Olivia Murtagh, Wesley J Wolfe, Timothy N Bullock, Benjamin W Purow, Gerald R Hammond, Ken Hsu
bioRxiv 2025.12.09.692983;
doi: https://doi.org/10.64898/2025.12.09.692983
Stereoselective recognition is a powerful means to differentiate selective versus non-specific activity of small molecules in complex biological systems. Here, we disclose stereochemically defined, sulfonyl-triazole inhibitors of the lipid enzyme diacylglycerol kinase-alpha (DGKA), a key metabolic checkpoint for T cell effector function. Acute treatment with the covalent DGKA inhibitor AHL-7160 recruited endogenous DGKA to the plasma membrane in a stereoselective and isozyme-specific manner. The membrane translocation activity of AHL-7160 correlated with blockade of cellular phosphatidic acid production and potentiation of primary T cell-mediated killing of a glioblastoma cell line. Quantitative chemoproteomics revealed Y669 and K411 as sites of AHL-7160 modification on endogenous DGKA in cells. Extended treatments resulted in proteasome-dependent and proteome-wide selective degradation of DGKA in T cells. Collectively, these findings establish covalent DGKA ligands as potent molecular glues with translational potential in immunotherapy.
