Ab initio structure determination from electron microscopic images of single molecules coexisting in different functional states.
We have developed methods for ab initio three-dimensional (3D) structure determination from projection images of randomly oriented single molecules coexisting in multiple functional states, to aid the study of complex samples of macromolecules and nanoparticles by electron microscopy (EM). New algorithms for the determination of relative 3D orientations and conformational state assignment of single-molecule projection images are combined with well-established techniques for alignment and statistical image analysis. We describe how the methodology arrives at homogeneous groups of images aligned in 3D and discuss application to experimental EM data sets of the Escherichia coli ribosome and yeast RNA polymerase II.
Elmlund
Dominika
D
Department of Laboratory Medicine, Karolinska Institutet, Novum, SE-141 86 Huddinge, Sweden.
Davis
Ralph
R
Elmlund
Hans
H
D000465:Algorithms; D020285:Cryoelectron Microscopy / Q000379:methods*; D004926:Escherichia coli; D005583:Fourier Analysis; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D008958:Models, Molecular; D053758:Nanoparticles / Q000737:chemistry*; D012319:RNA Polymerase II / Q000737:chemistry*; D012270:Ribosomes / Q000648:ultrastructure*; D015003:Yeasts
D012319:RNA Polymerase II