Fig. 2.

The NsD7:PA complex forms a double-stranded helix. (A) The NsD7:PA complex adopts a right-handed coiled structure. The coil shown comprises the content of three asymmetric units. PA molecules are shown as green (carbon), orange (phosphate), and red spheres (oxygen). (B and C) Two neighboring NsD7:PA coils form a defensin double helix. (D) The interior of the NsD7:PA oligomer harbors a series of intercalating isoleucine residues (I15 and I37). Top view is down the center of the oligomer; Bottom view is the same view rotated 90° on the horizontal axis.