Mechanism of the allosteric activation of the ClpP protease machinery by substrates and active-site inhibitors - Felix, Jan; Weinhäupl, Katharina; Chipot, Christophe; Dehez, François; Hessel, Audrey; Gauto, Diego F.; Morlot, Cecile; Abian, Olga; Gutsche, Irina; Velazquez-Campoy, Adrian; Schanda, Paul; Fraga, Hugo (Science Advances, 2019)
Coordinated conformational transitions in oligomeric enzymatic complexes modulate function in response to substrates and play a crucial role in enzyme inhibition and activation. Caseinolytic protease (ClpP) is a tetradecameric complex, which has emerged as a drug target against multiple pathogenic bacteria. Activation of different ClpPs by inhibitors has been independently reported from drug development efforts, but no rationale for inhibitor-induced activation has been hitherto proposed. Using an integrated approach that includes x-ray crystallography, solid- and solution-state nuclear magnetic resonance, molecular dynamics simulations, and isothermal titration calorimetry, we show that the proteasome inhibitor bortezomib binds to the ClpP active-site serine, mimicking a peptide substrate, and induces a concerted allosteric activation of the complex. The bortezomib-activated conformation also exhibits a higher affinity for its cognate unfoldase ClpX. We propose a universal allosteric mechanism, where substrate binding to a single subunit locks ClpP into an active conformation optimized for chaperone association and protein processive degradation.
published
yes
yes
Keywords: article