Bdellovibrio bacteriovorus 109D and
Bdellovibrio stolpii derive one of their major outer membrane proteins from the outer membrane of their prey. This prey-derived protein corresponds to the OmpF protein of
Escherichia coli. Bdellovibrios cultivated on
Salmonella typhimurium prey acquire the
Salmonella OmpF protein; this protein is distinguishable electrophoretically from the OmpF protein of
E. coli. Bdellovibrios containing the prey-derived OmpF protein are sensitive to killing by colicin A but not colicin E1, whereas bdellovibrios without this protein are completely resistant to colicin killing.