CRYOGENIC ELECTRON MICROSCOPY

Subject: Science & tech

Context: Using the technique of cryogenic electron microscopy (cryo-EM), Dr Bing Chen and colleagues at Boston Children’s Hospital have freeze-framed the spike protein in both its shapes — before and after fusion with the cell.

Concept:

• Cryo-electron microscopy is a specific type of electron microscopy that is based on the principle of forming a 3D image by collection and combination of thousands of projections of bio-molecules.
• With the help of this, the researchers can now visualize the processes never seen before by freezing the mid-movement of the bio-molecules.
• Cryo-electron microscopy makes it possible to freeze the bio-molecules at the cryogenic temperature ie, at -150°C, preserving their natural shape. By this, the structure of molecules is revealed in exquisite detail.
• It is significant for better understanding of basic Chemistry and for the development of pharmaceuticals as it simplifies and improves the imaging of bio-molecules.
• It facilitates the study of fine viruses, protein complexes and cellular structures at a molecular resolution as it gives the scientists an opportunity to have a look at the machinery of life in a 3D form.
• The earlier forms of electron microscopes made it impossible to study the bio-molecules in 3D form as the powerful beams often destroyed the biological matter.
• The resolution now has improved from shapeless blobs to imaging the proteins at atomic resolution. The Cryo-Electron Microscopy has broken several limitations, moving biochemistry into a new Era.