Improvements from focused refinements. (A) Improvements in density from the helical to single-particle reconstruction for the rigor and ADP-bound complexes. The helically averaged reconstruction for both complexes is shown in grey, while the focused refinements are overlayed colored orchid (rigor) and yellow (ADP-bound). (B) Improvements to specific regions of the motor domain, including the lever arm and converter as well as the essential light chain.