FIGURE 2.

MB-10 inhibits the import of substrates that use the TIM23 import pathway. A, the WT yeast strain expressing Su9-Ura3 was cultured in synthetic dextrose medium lacking uracil in the indicated concentrations of MB-10 for 24 h. The cell density is indicated as fold increase compared with growth in the presence of DMSO. The data represent the averages ± S.D. of n = 3 trials. B, MIC₅₀ analysis of WT, tim23-2, and tim10-1 strains with MB-10. Each strain was cultured in rich ethanol-glycerol medium in the presence of various concentrations of MB-10 for 24 h. 100% was set as A₆₀₀ of each strain grown in the presence of the vehicle control (1% DMSO). Average percentage of survival ± S.D. of n = 3 trials is shown. C–G, import assays were performed with radiolabeled precursors into mitochondria from the WT strain in the presence of MB-10 or the vehicle (1% DMSO). Non-imported precursor was removed by trypsin treatment. Precursors include Su9-Ura3 (C), Su9-DHFR (D), AAC (E), Tom40 (F), and Erv1 (G). 10% standard (Std) from the translation reaction is included. A representative gel is shown for each assay (n = 3). The last time point in the import reactions was quantified with ImageJ software; 100% was set as the amount of precursor imported in the presence of DMSO at end point in the time course. p, precursor; m, mature; i, intermediate.