Cryo-electron microscopy reaches atomic size resolution

 The news I refer to in this post are not directly associated to optical microscopy, but have to do instead with electron microscopy. A recent article in Nature reports an increase in resolution up to 1.22 Å with a cryo-EM reconstruction for the human membrane protein β3 GABAA receptor homopentamer. This resolution is high enough to find out the individual position of atoms in the protein studied, reports Science. Protein structure has been traditionally mapped by using x-ray crystallography since the 1950's, but in some cases it is not optimal or even possible to use this technic. These include membrane proteins, very large proteins or proteins associated with ribosomes. On the other hand, cryo-EM only works with a specific type of unusually rigid proteins.   

For a longer and deeper read about Cryo-EM technic, follow this link, or the Wikipedia page. 

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