Engineered enzyme erases a stubborn mark of aging by up to 70% in human tissue samples - Phys.org

What the report says

Phys.Org reported on July 22, 2026, that scientists at Revel Pharmaceuticals, working with researchers from Calico and the University of Colorado, have engineered an enzyme that can remove a difficult-to-reverse form of age-related protein damage in human tissue samples. The work, published in Nature Communications, focuses on Nε-carboxymethyl-lysine, or CML, a chemical modification that accumulates on long-lived proteins in tissues such as skin, arteries and the eye.

CML belongs to a broader class of compounds known as advanced glycation and lipoxidation end products, or AGEs. According to the report, CML buildup can stiffen tissues and is linked to inflammatory signaling through a receptor known as RAGE. Researchers have generally treated CML as a largely irreversible modification, with earlier strategies aimed more at slowing new damage than removing existing marks from proteins.

The team used directed evolution to develop an enzyme they call CMLase, starting from a microbial enzyme and screening more than 500 million variants across five rounds of engineering. In tests on laboratory-damaged proteins, CMLase cut detectable CML by 52%, and removed 97% after overnight exposure. In human samples, it reduced CML by 45% in proteins from a 64-year-old eye, by more than 70% in elderly artery sections and by 55% in skin tissue, Phys.Org reported.

The findings are early-stage and do not amount to an anti-aging therapy. Further studies would need to show whether the enzyme can safely reach damaged proteins inside living tissues and whether removing CML improves inflammation or tissue function. Still, the work suggests a possible route for studying and potentially repairing specific molecular damage associated with aging.