Colicins: a minireview.

Colicin are toxins that kill specifically E. coli bacteria. These cells have both an outer and a cytoplasmic membrane. Thus, three steps can be distinguished in colicin action: a) the interaction with specific receptors located at the cell surface, b) the uptake through the outer and eventually through the inner membrane, c) the action of the cell target that leads to cell death. In this short review, an overlook of these three steps is given.