Is pepsin acidic or basic?

Pepsin:

1. Pepsin is a digestive enzyme secreted by the chief cells or zymogenic cells.
2. Pepsin is secreted as an inactive enzyme pepsinogen.
3. But it is activated by the acidic environment of the stomach into pepsin.
4. The optimal pH for pepsin is 1.8.
5. The optimum pH range is 1.0 - 2.0, beyond the pH of 3.0 it gets completely inactivated.
6. It helps to convert proteins into smaller peptides (proteases and peptones) in the stomach.