Figure 1.

(a) Cartoon of the three-dimensional structure of the intact human prion protein, hPrP(23–230). The helices are orange, the β-strands cyan, the segments with nonregular secondary structure within the C-terminal domain yellow, and the flexibly disordered “tail” of residues 23–121 is represented by yellow dots. (b) Stereoview of an all-heavy atom presentation of the globular domain, with residues 125–228, in hPrP(23–230) in the same orientation as in a. The backbone is shown as a gray spline function through the C^α positions, hydrophobic side chains are yellow, and polar and charged side chains are orange. The figures were prepared with the program molmol (38).