FIG. 4.
AFM images of various alternative DNA structures. (A) AFM images of H-DNA stabilized by negative DNA supercoiling. The H-DNA structure is indicated with an arrow. (B) AFM images of bulges in supercoiled DNA formed by the supercoil induced dissociation of the duplex at the (ATTCT)29 region. Open regions are indicated with arrows [reprinted with permission from the American Chemical Society, Copyright 2002].40