The Efremov Lab


Structural Biology, Electron Microscopy

‚ÄčOur aim is to understand how large molecular machines work. To achieve this we are using transmission electron cryogenic microscopy (cryo-EM) and methods of single particle analysis to determine the structures of the molecular machines and to resolve their functionally important conformational states.
Many large protein complexes resemble human-made machines and mechanisms. Activity of these proteins is associated with large-scale conformational changes. We want to determine the structure of these protein complexes and see their conformation changes when they work. Due to intrinsic flexibility, molecular machines are often difficult to crystallize. To determine their 3D structure we use a method of single particle cryo-EM, which does not require crystals.
We focus primarily on the structures of large membrane protein complexes involved in trans-membrane ion transport. We want to determine their high-resolution structures in functionally important conformational states. This will allow us to understand how numerous factors alter protein conformation and regulate the trans-membrane ion transport.
The method of cryo-EM has a high potential for solving atomic resolution structures of large and intermediate sized protein complexes. Our second focus is related to the further development of the single particle analysis method, in particular techniques of sample preparation and image processing. Our goal is to determine the high-resolution 3D structures of specific conformational intermediates of protein complexes, inducing short-living intermediates and  high-resolution structures of flexible protein complexes.