class of enzymes

Pepsin is an enzyme. It acts on proteins in the stomach, which has a low pH because of the Hydrochloric acid. It works best at a pH of about 1.5.[1] It will not work at a pH above 6.

It was the first animal enzyme to be discovered. Theodor Schwann discovered it in 1836.

Pepsin is used to make cheese.


  1. "Effects of pH". Retrieved 2010-04-29.