Fig. 4

Unfolding pattern of the Omp FhuA depends on membrane environment. a Density map of 82 superimposed force–distance curves recorded from OMVs containing overexpressed FhuA. b Density map of 80 superimposed force–distance curves recorded from FhuA, reconstituted in lipid bilayers assembled from E. coli polar lipid extract. c Force vs. contour length plot showing the result obtained from fitting every force peak of every force–distance curve superimposed (a, b). Blue and green dots are from measurements from OMVs, red dots are from measurements from reconstituted FhuA. Colored curves (a, b) are WLC curves indicating the mean contour length of each unfolding force peak. Dashed and solid WLC curves indicate force peaks present in less than and more than 30% of the superimposed force-distance curves, respectively. Contour lengths are given in number of amino acids above the WLC curves. SMFS was recorded in buffer solution (DPBSS) at room temperature (see Methods)