Fig. 2.

Expression of hEGF and IL-3 in IBs upon fusion to ssTorA. Expression of either hEGF (a) or IL-3 (b) upon fusion to the signal sequences (ss) of E. coli TorA, PhoE, Hbp or DsbA as indicated. E. coli MC4100 cells were grown to early log-phase when fusion protein expression was induced by addition of anhydrotetracycline (ahtc). Samples were withdrawn from the cultures at the time point of induction (−ahtc) and 2 h after induction (+ahtc). Cells were analyzed by SDS-PAGE and Coomassie staining. Non-processed (*) and processed (>) forms of the respective fusion proteins are indicated. Molecular mass (kDa) markers are indicated at the left side of the panels. c E. coli MC4100 cells carrying pIBA-ssTorA/hEGF, pIBA-ssTorA/IL-3 or an empty pASK-IBA3 vector (EV) grown and induced as described under a and b were analyzed by phase-contrast microscopy. Examples of inclusion bodies are indicated with an arrow. Scale bar 2 μm