Figure 5. DBN93 inhibits 20S, but not ClpXP peptidase activity.
(a) Cleavage of FRETN 89–98 by ClpXP was monitored in the absence (black) and presence of 1 µM (light gray) or 4 µM (dark gray) DBN93. (b) In the presence of 500 µM ATP, 200 nM human 20S proteasome cleaves 100 µM FRETN 89–98 peptide (black). The addition of 2 µM DBN93 inhibited the cleavage (gray). This illustrates the need to isolate mitochondria from cytosol so Lon can be preferentially inhibited by DBN93.
