Figure 10.

A representation of the proposed mechanism for P22 VLP expansion using SDS. The exterior of P22 interior and exterior capsid surfaces are highly negatively charged. It is likely that interactions between the SDS molecules and capsid surfaces are repulsive. On the other hand, the hydrophobic alkyl chain of the SDS can interact with the hydrophobic regions found between CP subunits. The osmotic pressure caused by the cargo found on the inside of the capsid, together with the repulsive electrostatic interactions between the SDS molecules and CP, initiates the expansion of the P22 VLP.