Figure 3
Substitutions of the phenylalanine at position 3 with brominated phenylalanine analogues, shown in stereo and superimposed on the cQFD meditope (green C atoms). (a) Viewed from the top, tyrosine (purple C atoms) at position 3 blocks the extension of the side chain of Arg8 (R8). (b) Substitution with 2-bromophenylalanine (2-BrF; magenta C atoms) does not affect the positioning of R8; however, there are multiple conformation of the 2-BrF side chain. (c) Substitution with 3-bromophenylalanine (3-BrF; yellow C atoms) affects R8; however, it also produces a conformational change in Leu5 (L5). (d) Substitution with 4-bromophenylalanine (4-BrF; blue C atoms) slightly perturbs R8. (e) Side view with each variant superimposed on the cQFD meditope. |