Electron microscopy and structural analysis of human spliceosomes B and Bact, and hemoglobin of freshwater snail, B. glabrata

Single particle electron microscopy (EM) is a structural biology technique allowing to obtain class averages of two-dimensional (2D) images or three-dimensional (3D) models of biological macromolecular complexes. In contrast to other structure determination methods, like X-ray crystallography and nuclear magnetic resonance (NMR), considerably lower amounts of biological complexes are required. Therefore, single particle EM is the method of choice for structural studies of large biomacromolecular complexes which are difficult to purify in large quantities. However, the hugest challenge for single particle EM is the inherent dynamism of these large biomacromolecular complexes. This can be overcome by either improved sample preparation, improved image processing methods or both. In this work two examples of large complexes were studied by single particle EM: human spliceosomal complexes and hemoglobin of snail B. glabrata.