FIG 8.
The outer membrane protease CroP is present in C. rodentium OMVs. OMVs were isolated from C. rodentium strains grown to mid-log phase in the presence of 50 μM FeCl2. (A) The relative amounts of CroP found within equal volumes of isolated OMVs were determined by Western blotting using an anti-CroP antibody. (B) CroP activity of OMVs were assessed by incubating equal volumes of OMVs isolated from different C. rodentium strains with the C2 FRET substrate for 20 min. Cleavage of the FRET substrate was determined by measuring relative fluorescence at 430 nm after excitation at 325 nm. Data shown are representative of three independent experiments. Data were fitted to a Michaelis-Menten nonlinear regression curve using GraphPad Prism 7 software.