  Cryogenic electron microscopy is widely used in structural biology, but its
resolution is often limited by the dynamics of the macromolecule. Here, we
developed a refinement protocol based on Gaussian mixture models that
integrates particle orientation and conformation estimation, and improves the
alignment for flexible domains of protein structures. We demonstrated this
protocol on multiple datasets, resulting in improved resolution and
resolvability, locally and globally, by visual and quantitative measures.
