| Popis: |
When water is suddenly cooled to temperatures below –140°C, by careful methods such as plunging it into a bath of liquid nitrogen, it forms an amorphous structure that is more like a glass than a crystal. Called vitreous ice, this substance cannot be found in nature but can be used to preserve samples for use with an electron microscope. When biophysicist Chikashi Toyoshima first heard of this technique in graduate school at the University of Tokyo, he knew immediately it was a powerful tool to help reveal the structure of biological samples that would otherwise be crushed in the vacuum of electron microscopes. He traveled across the Pacific to learn the technique in California and eventually used the technique to determine the structure of membrane proteins in tubular crystals, providing images of these biological structures for the first time. |
