Figure 1.

Scanning approach used to map the membrane–water interfaces and search for signal-stabilizing interfacial mutations. Shown are the sites of cysteine and arginine substitutions selected for the present study, all located at interfacial positions on the signaling helix TM2 that carries signals across the membrane. The two symmetric subunits of the homodimer are shown in white and gray, respectively, and individual helices are depicted as cylinders.