Recombinant E. coli HTRA/Protease Do Protein, CF

As a heat shock protein and a serine protease, HTRA (Protease Do or the DegP protease) is indispensable for bacterial survival at temperatures above 42 °C (1). It is a periplasmic protein with a signal peptide of 26 amino acid residues. The mature protein contains two 90 amino acid PDZ domains, which start at residue 280. The serine protease activity is inhibited by diisopropyl fluorophosphate or dichloroisocoumarin. Four human proteins have been identified that are homologous to E. coli HTRA and believed to play a role in arthritis, cell growth, unfolded stress response, apoptosis, aging, and tumor progression (2).

• HTRA/Protease Do Proteins and Enzyme