Figure 2. Cryo-EM density maps of two independent data sets and 3D reconstructions after 38 refinement iterations.

With maps generated from data sets 1 and 2 (a) and their combined maps (b). The initial model for each data set/reconstruction was generated using EMAN1. Subsequent refinement was computed using MPSA. The final five iterations were completed in EMAN1, resulting in the final 3D density maps.