SLAC public Lecture Series
Caught on Camera: The Secret Lives of Life's Molecules
For decades, scientists have been working to understand the building blocks of life by studying the structures of proteins and other large biological molecules. Using clever tricks with microscopes, electrons, and X-rays, it is possible to see the precise arrangements of atoms in these complex molecules. This sharp view of biological structure is especially important for understanding the mechanisms of disease and designing drugs that specifically target the action of proteins in viruses and bacteria. With conventional methods, though, we can take these pictures only when the molecules are artificially held still, for example by immobilizing them in crystals at temperatures far below freezing. Now, the LCLS X-ray laser at SLAC can deliver a beam so intense that it can take high-resolution pictures of biological molecules under natural, room-temperature conditions, even as they carry out their destructive biochemistry. Often, the new pictures differ in significant ways from those of frozen structures. This lecture describes how this new imaging method gives us a real-time view of the molecules' action and opens new opportunities for discovering drugs and understanding our body's basic chemical processes.