Single particle analysis

The overview of single particle analysis is shown.

Protein particles are ice-embedded in random directions, thus allowing the three-dimensional electron microscopic imaging of protein particles from various directions of 2D images/projections. The images allow the structural analysis of proteins using single particle analyses.

In single particle analyses, the images of protein particles are collected, and images similar in the directions of three-dimensional projection are superimposed and averaged. The averaging results in low-noise two-dimensional images. These images are used again as references for positioning the original images to obtain new averaged images.

After repeating these procedures, three-dimensional angles (Euler angles) are determined to construct a three-dimensional structure. In addition, a re-projected image is created from the initial three-dimensional structure. The image is subjected to averaging through the superposition of the original image as a reference to reconstruct a three-dimensional structure. These procedures are repeated until the structure is stabilized, in order to complete a structural model. In this training, the principles of single particle analyses and single particle analyses using Eos will be learned.