How Serpins Are Shaping Up

摘要

Survival of the fittest is a rule that ap- plies just as much to protein families as it does to organism. The serpins are a protein family of highly adaptable serine protease inhibitors that have out- maneuvered their many relatives to be- come the predominant protease inhibitors in human plasma. Their success can be at- tributed to their ability to trapand irre- versibly bind to their target proteases (see the figure) (1). Cleavage of the serpin's re- active loop by the protease triggers entrap- ment and inactivates the serpin.