Figure 3.

Annealed Fo–Fc omit electron density maps for the NNQQNY segment inserted in T7EI, showing that the conformation of NNQQNY differs from that in its steric zipper structure. This figure is shown in stereoview. (A) A ribbon representation of a T7EI−NNQQNY dimer with NNQQNY residues shown as sticks. (B−F) Annealed Fo–Fc omit map for NNQQNY residues contoured at 6.0σ. Residues NNQQNY are shown as sticks. Notice that the main-chain atoms of NNQQNY are largely resolved and the side chain of tyrosine at position 50 in all 10 chains has relatively strong density.