Model for interaction between membrane anions, C5b-6 and C7. (A) Binding of C5b-6 to anionic lipids via the grouped positive charges of the conserved TS1 domain in C6. (B) The effect of C7 addition. Binding of C7 via anionic residues disrupts the membrane-C5b-6 interaction and leads to exposure of hydrophobic residues, resulting in the dissociation of the C5b-7 complex from the anionic molecule and insertion into the lipid bilayer. TS represents the highly conserved TS1 domain in C6. H represents the hydrophobic domains of C5b, C6, or C7.