C R E D I T: MA RT I N H Ö G BO M/ STO C KH O L M UN I V ERS I T Y ( ST RU CTU R E ) ; MRC L A B O RATO RY O F M O L ECU L AR B I O LO GY (H E N DE RSO N ); CO LU M B I A U N I V E RSI T Y M E DI CAL COL LEGE (FRAN K); U OF LAUSAN N E (DUBOC H E T )
Concentrates Chemistry news from the week
▸ Highlights Circadian rhythm pioneers honored with Medicine Nobel 6 A simple test to tell Zika virus from dengue 7 Detection of gravitational waves wins Physics Nobel 8 Organic material has long-lasting luminescence 10 Chemical makers step up dumping claims 17 Chinese carmaker backs lithium company 18 Cancer drug start-up Navire launches 19 Journals push for copyright control 22
NOBEL PRIZE
Cryo-EM earns chemistry Nobel Three scientists honored for developing technique that provides unprecedented views of biomolecules the technique to handle some structures The 2017 Nobel Prize in Chemistry has that crystallography and NMR cannot. For been awarded to Jacques Dubochet of the example, it eliminates the need to crystalUniversity of Lausanne, Joachim Frank of Columbia University, and Richard Hender- lize biomolecules, which can be difficult. In addition, cryo-EM specialist Sarah son of the MRC Laboratory of Molecular Butcher of the University of Helsinki esBiology. They earned the prize “for develtimates that the technique can analyze oping cryo-electron microscopy for the high-resolution structure determination of 100-fold larger structures than NMR or Henderson (from crystallography can, including whole vibiomolecules in solution.” The scientists left), Frank, and ruses and even frozen cells. That makes will equally share the $1.11 million award. Dubochet it “much, much more adaptable to lots of In cryo-electron microscopy (cryo-EM), different types of biological questions” than images obtained a beam of electrons is sent through a biowith weak electron the other two techniques, she says. molecular sample that has been frozen. beams. During Henderson set the groundwork for The material deflects the electrons in a way the next decade, cryo-EM in 1975, when he used electron that permits researchers to determine the Frank, then at the microscopy to determine a three-dimenbiomolecule’s structure. Electron beams Wadsworth Center, sional model of bacteriorhodopsin by physically damage biomolecules, but in Albany, developed image-processing averaging multiple freezing them, the “cryo” part of cryo-EM, technology for converting conventional protects them from electron damage and 2-D electron microscopy images into 3-D prevents them from getting dehydrated in structures. the instrument’s vacuum chamber. In the early 1980s Dubochet devised Structures obtained by cryo-EM and methods for rapidly freezing biomolecrelated techniques are of fundamental ular samples, and in 1990, Henderson obimportance for understanding life chemtained the first atomic-resoistry, and they can help scienlution cryo-EM structure, tists develop drugs by elucidatof bacteriorhodopsin. ing the way bioactive agents In the past decade, interact with biomolecules. advances in electron-detec“Proteins are in all living tion technology, particularly things—humans, plants, anithe development of direct electron mals, bacteria,” says Allison A. detectors, have greatly improved cryoCampbell, president of ACS. The EM’s resolution capabilities. These prize “highlights the role that chemistry detectors, now commercially availplays in every aspect of our lives. From able, and data-handling improvements the medicines we take to the plants we “caused a huge revolution in the quality grow, understanding proteins—and of cryo-EM data,” Butcher says. “Now the chemistry of those proteins—is that means we can recover all the incritical.” Artistic representation of cryo-EM structures formation and go to atomic resolution, Traditionally, scientists turned to of glutamate dehydrogenase with increasing which is what crystallographers do. But X-ray crystallography and nuclear magresolution from left to right. Electron detector netic resonance spectroscopy to obtain technology advances played a key role in making we can do it without having to make biomolecular structures. Progress in it possible for cryo-EM to routinely attain atomic crystals, and crystals are a pain.”—STU cryo-EM, however, eventually enabled resolution (ribbon structure, far right). BORMAN OCTOBER 9, 2017 | CEN.ACS.ORG | C&EN
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