Glossary
Urease — Glossary
The bacterial enzyme that splits urea into ammonia — the driver of the ammonia smell in aging urine.
Urease is the enzyme bacteria use to break urea down into ammonia. It’s produced by the bacteria living in urine residue — which means a urine deposit is a self-contained ammonia factory: the urea is there, the bacteria arrive, the urease runs.
This is why urine odor worsens with time rather than fading — the urease keeps converting urea to ammonia until the substrate is gone.