Imprimir Republish

CHEMISTRY

Biological molecules in 3D

UNIL | MRC LABORATORY OF MOLECULAR BIOLOGY | COLUMBIA UNIVERSITY MEDICAL CENTER Jacques Dubochet, Richard Henderson, and Joachim FrankUNIL | MRC LABORATORY OF MOLECULAR BIOLOGY | COLUMBIA UNIVERSITY MEDICAL CENTER

Nobel has honored cryo-electron microscopy, a technique which has revolutionized biochemistry by allowing us to model the three-dimensional atomic structure of biological molecules. Scottish biologist Richard Henderson, 72, from the University of Cambridge, UK, along with biophysicists Joachim Frank, 77, a German from Columbia University, USA, and Jacques Dubochet, 75, from the University of Lausanne, Switzerland, split the prize equally. Henderson was the first person to create a three-dimensional image with an atomic resolution using cryo-electron microscopy in 1990. Until then, the most detailed images were obtained using crystallography, a method that was not always successful. “Quite a lot of structures in biology were resistant to other methods like x-ray crystallography or nuclear magnetic resonance spectroscopy,” Henderson explained to the Nobel Prize website. This was the case with the cell membrane proteins he studied. Between 1975 and 1986, Frank developed a processing method that enabled the creation of a precise three-dimensional model based on two-dimensional images. The possible applications of this technique were numerous. Dubochet discovered a special way of adding water to the system. In the vacuum required for the microscope to function, the liquid water evaporates and the molecules collapse. But by rapidly cooling the drop of water around the sample, it solidifies into a glass-like structure (a process known as vitrification), allowing the molecules to maintain their natural shape. It is thus possible to observe their structures, to see how the shape of a protein changes in certain situations, and how the molecules interact. “The use of cryo-electron microscopy to analyze biomolecules allows us to see molecules in the exact state that they exist in a solution,” says physicist Rodrigo Portugal, from the Brazilian National Nanotechnology Laboratory (LNNano) in Campinas.

Republish