Improving Resolution and Resolvability of Single Particle CryoEM using Gaussian Mixture Models

TL;DR

This paper introduces a Gaussian mixture model-based refinement protocol for cryoEM that enhances resolution and resolvability by better estimating particle orientation and conformation, especially for flexible protein domains.

Contribution

The novel protocol integrates orientation and conformation estimation using Gaussian mixture models to improve cryoEM structure refinement.

Findings

Improved resolution and resolvability in multiple datasets

Enhanced alignment of flexible protein domains

Quantitative and visual validation of improvements

Abstract

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.