Amino acid sidechains adopt different conformational states, or rotamers. Rotamers from the Dunbrack backbone-dependent library or the Richardson "penultimate" library can be viewed, evaluated, and incorporated into structures with the Rotamers tool. A residue can be changed into a different conformation of the same type of amino acid or mutated into a different type. Rotamer torsion angles and library probability values are listed in a dialog, along with (optionally) hydrogen bonds, clashes, and agreement with electron density data. Only rotamers chosen in the list are displayed. When a single rotamer is chosen, it can be incorporated into the structure. The image includes 2D labels.

Potassium channel (Protein Data Bank entry 1bl8) on a dark slate blue background with potassium ions shown in firebrick. The channel is comprised of four chains. Each chain has been rainbow-colored from blue at the N-terminus to red at the C-terminus, but only the surface of the channel is shown. The surface has been sliced with a per-model clipping plane. The surface cap color is plum except with opacity set to 0.8. The shininess and brightness have been set to 128 and 8, respectively, and the lights on the scene have been moved from their default positions. The subdivision quality (related to the smoothness of the spherical ions) is 5.0, and the molecular surface was computed with probe radius and vertex density set to 1.0 and 6.0, respectively. (More samples...)