The study unexpectedly identified a significant role for a group of enzymes known as agmatinases, which convert the metabolite agmatine into polyamines. These enzymes appear to participate in a previously unrecognized “metabolic feedback loop” that helps maintain balanced TOR activity. When agmatinase activity was disrupted, yeast cells grew more quickly but showed signs of premature aging, revealing a trade-off between rapid growth and long-term cell survival.

The team also found that adding agmatine or putrescine (a related compound) supported longevity in yeast and improved growth under specific conditions.

“By showing that agmatinases are essential for healthy aging, we’ve uncovered a new layer of metabolic control over TOR — one that may be conserved in humans,” said Dr. Rallis. “Because agmatine is produced by diet and gut microbes, this work may help explain how nutrition and the microbiome influence aging.”