Steps in structure determination of the EDTA-treated YiiP/Fab complex from the SP3 dataset. (A) Representative micrograph. (B) Selection of 2-D class averages showing multiple views of the complex. (C) Heterogeneous refinement job in cryoSPARC revealed the presence of two distinct conformations, which were individually used for high-resolution refinement. (D) Nonuniform refinement jobs for each class in cryoSPARC colored according to local resolution, which ranged from 3.0 to 7.0 Å. Fourier shell correlation (FSC) plots indicate an overall resolution of 3.4 and 4.2 Å for the symmetric conformation and the bent conformation, respectively. (E) Three principle components derived from 3-D variability analysis of the combined particles from both classes.