FIGURE 6.

Specific DNA-induced folding of Trp-70 variants. Free and DNA-bound domains are indicated by open and closed circles, respectively. Increases in helical signal are indicated by gold arrows at the helix-sensitive wavelength of 222 nm (B–E). A, CD spectra of the W70L domain in free (open circles) and bound (closed circles) states at 4 °C. The spectrum of the free DNA site is shown as a black line. The near-UV band maximum of the variant domain·DNA complex is shifted relative to the free DNA site (bracket). B and C, W70A andW70L are more structured when bound to DNA. D and E, DNA-induced increase in helical structures of the aromatic containing variants W70F (D) and W70Y (E) at 37 °C.