PDK1 Enzymatic Assay: The experimental batches are carried out in a flashplate system with 384 wells/microtitration plate.In each case, the PDK1 sample His6-PDK1(Δ1-50)(3.4 nM) (His6 disclosed as SEQ ID NO: 2), the PDK1 substrate biotin-bA-bAKTFCGTPEYLAPEVRREPRILSEEEQEMFRDFDYIADWC (SEQ ID NO: 3) (400 nM), 4 uM ATP (with 0.2 uCi of 33P-ATP/well) and the test substance in 50 ul of conventional experimental solution per well are incubated at 30° C. for 60 min. The test substances are employed in corresponding concentrations (if desired in a dilution series). The control is carried out without test substance. The reaction is stopped using standard methods and washed. The activity of the kinase is measured via the incorporated radioactivity in top count. In order to determine the non-specific kinase reaction (blank value), the experimental batches are carried out in the presence of 100 nM staurosporine.
Luminex Assay: The cellular assay for the determination of the PDK1 kinase activity is carried out as a Luminex assay in the 96-well format. PC3 cells are sown at 20,000 cells per well in 100 ul of medium (45% of RPMI1460/45% of Ham's F12/10% of FCS) and incubated on the following day for 30 min with a serial dilution of the test substance (7 concentrations) under serum-free conditions. The cells are subsequently lysed using 90 ul of lysis buffer (20 mM tris/HCl pH 8.0, 150 mM NaCl, 1% of NP40, 10% of glycerol, 1% of phosphatase inhibitor I, 1% of phosphatase inhibitor II, 0.1% of protease inhibitor cocktail III, 0.01% of benzonase) per well, and the lysates are separated off from insoluble cell constituents by means of centrifugation through a 96-well filter plate (0.65 um). The lysates are incubated overnight at 4° C. with shaking with Luminex beads to which an anti-total PKB antibody is coupled. The detection is carried out on the following day by addition of a phospho-T308-PKB antibody and a species-specific peroxidase-labelled secondary antibody.