Substrate-Selective Inhibition of Protein Kinase Pdk1 by Small Compounds that Bind to the Pif-Pocket Allosteric Docking Site.
Busschots, K., Lopez-Garcia, L.A., Lammi, C., Stroba, A., Zeuzem, S., Piiper, A., Alzari, P.M., Neimanis, S., Arencibia, J.M., Engel, M., Schulze, J.O., Biondi, R.M.(2012) Chem Biol 19: 1152
- PubMed: 22999883 
- DOI: https://doi.org/10.1016/j.chembiol.2012.07.017
- Primary Citation of Related Structures:  
4AW0, 4AW1 - PubMed Abstract: 
The PIF-pocket of AGC protein kinases participates in the physiologic mechanism of regulation by acting as a docking site for substrates and as a switch for the transduction of the conformational changes needed for activation or inhibition. We describe the effects of compounds that bind to the PIF-pocket of PDK1. In vitro, PS210 is a potent activator of PDK1, and the crystal structure of the PDK1-ATP-PS210 complex shows that PS210 stimulates the closure of the kinase domain. However, in cells, the prodrug of PS210 (PS423) acts as a substrate-selective inhibitor of PDK1, inhibiting the phosphorylation and activation of S6K, which requires docking to the PIF-pocket, but not affecting PKB/Akt. This work describes a tool to study the dynamics of PDK1 activity and a potential approach for drug discovery.
Organizational Affiliation: 
Research Group PhosphoSites, Department of Internal Medicine I, Universitätsklinikum Frankfurt, Theodor-Stern-Kai 7, 60590 Frankfurt, Germany.