Seminar by Dr. Vinothkumar Kutti Ragunath, NCBS-TIFR, Bangalore, on "Realising the full potential of electron cryomicroscopy"
06 Jun 2019
Seminar Room # 350
Talk Title : "Realising the full potential of electron cryomicroscopy"
Abstract
There has been enormous progress during the last few years in the
determination of three-dimensional (3D) biological structures by single
particle electron cryomicroscopy (cryoEM), allowing maps to be obtained to
higher resolution and from fewer images than required previously. This is
principally due to the introduction of the direct electron detectors that
has 2- to 3-fold higher detective quantum efficiency (DQE) and to the
improvement of the computational algorithms for image processing. In
spite of the great strides that have been made, quantitative analysis
shows that there are still significant gains to be made with detectors
with higher DQE and faster frame rate and that the problems associated
with image degradation can be solved, possibly by minimising beam-induced
specimen movement and charge build up during imaging. If this can be
achieved, it should be possible to obtain near atomic resolution
structures of smaller single particles, using fewer images and resolving
more conformational states than at present, thus realising the full
potential of the method. I will illustrate using select biological
macromolecules how recent advances help in elucidating the atomic
resolution structures and distinct states and how the technique is
applicable to study macromolecules within the cell.