Fig. 5.

ArgT undergoes proteolysis in periplasmic space of S. flexneri. A, the periplasmic proteins (periplasm) and the remaining whole-cell proteins (cytoplasm + membrane) of induced 2457T/pProEX-argT cells were extracted from cultures grown at 37 and 30 °C. ArgT expression products were only detected in the periplasm of 2457T grown at 30 °C. B, 2457T/pGEX-argT (with signal peptide) and 2457T/pGEX-argT2 (without signal peptide) were induced by IPTG at 30 °C and then incubated at 37 and 30 °C for 4 h. Due to the cleavage of the signal peptide, the ArgT detected in 2457T/pGEX-argT is smaller than that in 2457T/pGEX-argT2. M, protein marker (Fermentas).