Figure 3

A representative X-ray PA protease structure from Streptomyces griseus and modeled PA protease structures from Plasmodium falciparum, Pyrococcus furiosus, Neurospora crassa and Arabidopsis thaliana . Ribbon models of S. griseus, 1SGC (A), P. falciparum (C), P. furiosus (E), N. crassa (G) and A. thaliana (I) PA protease structures show β-sheets with an arrow directed to the C-terminus (light blue), α-helices (red and yellow), turn/loops (gray), and catalytic triad residue side chains (green sticks). Surface electrostatic potential model of S. griseus, 1SGC (B), P. falciparum (D), P. furiosus (F), N. crassa (H) and A. thaliana (J) PA protease structures show electronegative (red), electropositive (blue) and electroneutral (white) amino acid side chains. The estimated position of the oxyanion hole (OA) is also indicated.