FIGURE 2.

Structural superimposition of interacting helices 18 and 19 from the TM protein cytochrome c oxidase, 1occ (red) and interacting helices 7 and 8 from the soluble protein chaperone HSC20, 1fpo (white). The side chains of interfacial residues are shown in stick form. A structure-based sequence alignment of the helices is shown below the superimposition, where interfacial residues are highlighted in red. Identical residues that adopt essentially the same conformations are marked in the sequence alignment with green boxes, and on the structure with green circles.