These are images for comparison:
Chymotrypsin, a serine protease
catalytic Ser195=red; His57=yellow; Asp102=orange; substrate/inhibitor=purple
HIV protease, an aspartyl protease
catalytic Asp25,25' of dimer=orange; inhibitor=purple
Enolase (glycolysis)
red=alpha helix, cyan=beta, green=turn,
active site residues=magenta; inhibitor (fluoride + magnesium phosphate)=purple