Steps in structure determination of the EDTA-treated YiiP/Fab complex from the SP2 dataset. (A) Representative micrograph. (B) Selection of 2-D class averages showing multiple views of the complex. (C) Heterogeneous refinement job in cryoSPARC was used to look for multiple conformations and to select a homogeneous subset of particles for high-resolution refinement. (D) Nonuniform refinement job in cryoSPARC colored according to local resolution, which ranged from 4.0 to 7.0 Å for the best class. Fourier shell correlation (FSC) plot indicates an overall resolution of 4.0 Å, which was determined without imposition of symmetry. VL, variable light chain.