Cryo-electron microscopy (cryo-EM) is a form of transmission electron microscopy (TEM) where biological samples are studied at cryogenic temperatures. It is becoming a more and more important technique in the field of structural biology, as has been manifested by many once hard-to-determine macromolecular structures. With the rapid advancement of both hardware and software, the resolution of cryo-EM maps is improving steadily. In some cases, near-atomic resolution had been obtained, including those of viruses, ribosomes, mitochondria, ion channels, and enzyme complexes as small as 150 kD. Cryo-EM Small Protein https://www.creative-biostructure.com/cryo-em-for-small-proteins-561.htm