FIG. 2.

Temporal profile of protein contents of BCG grown in the Wayne dormancy culture system. Protein extracts were prepared at the time points (A to D) indicated by the arrows in Fig. 1. Samples (100 μg) of total protein were prepared from ≈ 100 ml of culture at time point A and ≈ 35 to 50 ml of culture at time points B to D and were subjected to two-dimensional electrophoresis. Panels A to D show silver-stained gels corresponding to the four time points. Arrows 1 to 4 indicate dormancy-induced protein spots. The arrowhead shows the 22-kDa alkyl hydroperoxide reductase (AhpC, Rv2428; 6, 35) which was found to be down-regulated in the hypoxic stationary phase. Molecular masses (MW) are indicated in kilodaltons. The experiment was carried out four times with the same results. Growth phase-dependent protein contents were also analyzed using isoelectric focusing strips at pHs 3 to 10. No additional dormancy-induced proteins were detected.