Antibiotic cell membrane effect. Artwork of the natural antibiotic peptide defensin (orange) disrupting the cell membrane of a bacterium (top right). The defensin inserts itself into the lipid bilayer (top) and rotates, causing the lipid molecules to reconfigure themselves (centre). This eventually leads to the membrane splitting to form a pore (bottom), which causes the cell contents to leak out, destroying the bacterium. The initial insertion of the defensins is by electrostatic attraction.