Fig. 2. Translocation of Momp2 into membrane vesicles is achieved solely by SecA, SecB and the F1-ATPase. pOmpA, MtlA and Momp2 were synthesized in vitro in the presence of the components indicated at the top (INV, E.coli inside-out inner membrane vesicles; U-INV, urea-extracted INV). SecA (80 ng/µl), SecB (40 ng/µl), F1-ATPase (40 ng/µl), Ffh (2 ng/µl) and FtsY (20 ng/µl) were added as specified. Translation products were either precipitated directly with TCA or only after incubation with 0.5 mg/ml proteinase K (PK) for 20 min at 25°C. Indicated are the positions of the precursor (pOmpA) and the signal sequence-free form of OmpA, of full-length MtlA and its fragment resistant towards proteinase K (MtlA-MPF), and of Momp2 and its fragment resistant towards proteinase K (Momp2-MPF).