סמינר לפיזיקה של מערכות ביולוגיות וחומרים רכים: Rethinking cryo-electron tomography: from imaging to diffraction and back

Abstract:

Cryo-electron microscopy has revolutionized the field of structural biology with near-atomic resolution analysis of proteins and nucleic acids. Almost simultaneously, structure prediction by computer became both practical and reliable. With this convergence, attention turns inceasingly to the 3D cellular context and therefore to tomography. Only very thin specimens can be addressed by conventional (wide-field) transmission EM imaging, which raises an obvious internal contradiction. Our lab has promoted the use of scanning transmission EM to circumvent the most severe thickness limitations. STEM is inherently a diffraction method, whose potential is nearly untapped. Drawing on examples from crystal formation in blood parasites, 3D imaging of organelles, and bacteriophage, the talk will describe the latest tools we develop to enhance spatial resolution and to introduce a complementary element of material analysis.