FIGURE 2: Pf phages organize the P. aeruginosa biofilm matrix into a liquid crystal.

The birefringence of the liquid crystalline biofilm matrix can be visualized by placing colony biofilms on an agar pad between crossed polarizing lenses. The liquid crystalline matrix can change the polarization of light allowing it to pass through both polarizing lenses. Thus, non-liquid crystalline biofilms appear opaque (red arrow) while liquid crystalline biofilms appear bright (blue arrow). The organization of the biofilm matrix into a liquid crystal enhances adhesion, antibiotic tolerance, and desiccation survival. Further, Pf phage can increase the viscosity of host polymers such as mucin and DNA.