Metals affect the structure and activity of human plasminogen activator inhibitor-1. I. Modulation of stability and protease inhibition.

Human plasminogen activator inhibitor type 1 (PAI-1) is a serine protease inhibitor with a metastable active conformation. Under physiological conditions, half of the inhibitor transitions to a latent state within 1-2 h. The interaction between PAI-1 and the plasma protein vitronectin prolongs this active lifespan by ∼50%.