Figure 4.

Effect of dsbA, ΔtrxA, dipZ, and dsbC mutations on urokinase activity. Lysates of strains grown to mid-logarithmic phase were separated on non-reducing SDS/PAGE gels and urokinase activity was shown by activation of plasminogen on plasminogen/casein agar. Zymograms of lysates from strains RI89 (wild type), RI90 (dsbA::kan1), RI258 (ΔtrxA), RI242 (dipZ::mini-Tn10Cam1), and RI179 (ΔdsbC::cam) are shown in A. Relative activities of the mutants were estimated by comparison to dilutions of the wild-type lysate. (B) The indicated strains were grown without DTT, in the presence of 1 mM reduced DTT (red. DTT) or 1 mM oxidized DTT (ox. DTT).