Freeze-frame pictures of molecules receive chemistry Nobel Prize
The 2017 Nobel Prize in Chemistry was awarded to three researchers who developed a technique that helps scientists reveal some of the smallest details of life. Richard Henderson, Joachim Frank, and Jacques Dubochet received the prize for their work on cryo-electron microscopy, or cryo-EM, which allows scientists to take pictures of not just molecules, but atoms themselves, and view how they behave and interact.
Why it matters: The full potential of cryo-EM is only just being explored, but it is already been used to address practical problems. Cryo-EM revealed the atomic structure of the Zika virus, which could help scientists design vaccines and learn why it causes microcephaly. Eventually, researchers would like to use it to create movies of proteins and molecules at work.
How it works: Cryo-EM builds upon electron microscopy, a technique developed almost 100 years ago that creates an image by shooting a beam of electrons at a specimen. Most living organisms are comprised of water, but for electron microscopy to work, the object needs to be in a vacuum - but vacuums dry out objects, which changes their structure. Cryo-electron microscopy instead traps the specimen below a thin film of frozen, glasslike water, letting scientists view the molecules in the same environment they naturally occur. It could lead to "a revolution in biochemistry," says the Academy.
- Joachim Frank from Columbia University refined the process of electron microscopy. He photographs the shadows of molecules. Different angled molecules produce different shadows. Those images can be combined to infer a 3D structure.
- Richard Henderson from the MRC Laboratory of Molecular Biology in Cambridge, U.K. took the first high-resolution picture of a protein using the technique. Prior to this, researchers had believed that electron microscopy could only be used to image non-living objects.
- Jacques Dubochet from the University of Lausanne in Switzerland found a way to freeze the molecules without causing image-obscuring ice crystals to form. Now we can see not just the outer shapes of the molecules, but the atomic details inside.
What's next: Cryo-EM is still in its early days, but there's a lot it can do. Because cryo-EM involves flash-freezing molecules, the pictures capture a moment in time. Researchers hope to assemble these freeze-frame images into a movie, so they can view how proteins move and interact in cells.