Mode of action of colicin ib: formation of ion-permeable membrane channels.
Addition of purified colicin Ib to whole Escherichia coli cells or cytoplasmic membrane vesicles inhibits their subsequent ability to generate a membrane potential. In addition, this colicin is shown to bring about a voltage-dependent increase in the conductance of an artificial planar bilayer membrane prepared from soybean phospholipids. This results from the formation of ion-permeable channels. These data provide strong evidence that the depolarization of Escherichia coli cells by this colicin results from an Ib-induced increase in membrane permeability to ions.
D002462:Cell Membrane / Q000502:physiology*; D002463:Cell Membrane Permeability; D003087:Colicins / Q000494:pharmacology*; D004926:Escherichia coli / Q000502:physiology*; D007473:Ion Channels / Q000502:physiology*; D008564:Membrane Potentials / Q000187:drug effects*; D008567:Membranes, Artificial
D003087:Colicins; D007473:Ion Channels; D008567:Membranes, Artificial