Figure 2.

Dilution experiment to determine whether assembled ClpAP recognizes substrates. ClpAP complexes were formed by incubating 0.8 pmol each of ClpA and ClpP in 10 μl of buffer A containing 1 mM ATP[γ-S] for 10 min at 23°C. Complexes were diluted to 1 ml with buffer A containing 0.005% Triton X-100. Then 90 pmol of [³H]RepA or 70 pmol of [³H]α-casein and 1 mM ATP were added, and the mixtures were incubated for 5 min at 23°C. TCA was added to 20% and radioactivity in the acid-soluble fractions was measured. Control experiments were performed with added or omitted components as indicated. Results are means (±SEM) of three independent experiments.