This month, six Americans, including three chemists and three biologists, were honored with one of the scientific community’s highest honors, the Nobel Prize. Sharing the 2013 Prize in Physiology or Medicine were James E. Rothman, Randy W. Schekman, and Thomas C. Südhof, while the 2013 Prize in Chemistry went to Martin Karplus, Michael Levitt, and Arieh Warshel. OSTP Director John P. Holdren called each of the winners to congratulate them on their outstanding achievements, and will host a celebratory meeting with them at the White House before they travel to Sweden to collect their awards in December.
In the field of Physiology or Medicine, the Nobel Prize Committee selected the winners “for their discoveries of machinery regulating vesicle traffic, a major transport system in our cells.” As that language suggests, cell interiors are busy places, with molecules such as hormones and enzymes getting hauled like cargo inside bubble-like vesicles and then released at incredibly specific times and locations. The three laureates dramatically enhanced understanding of vesicle traffic-control in cells, providing insights that have proven critical to the study of diseases, brain signaling, hormone release, and neurological and immunological disorders, among other biological processes.
Schekman, of the University of California, Berkeley, was supported by funding from the National Science Foundation (NSF) as he studied mutations and various defects within cells to reveal three classes of genes that control different aspects of cellular transport systems.
Rothman, of Yale University, also received NSF funding and discovered a protein complex that targets vesicles and then binds them to their destination like two sides of a zipper. The proteins bind only in specific combinations, ensuring that each vesicle is delivered to its correct destination within a cell before releasing its contents.
Südhof, of Stanford University, identified proteins that, in response to timed influxes of calcium ions, open the zipper structure discovered by Rothman, allowing precisely timed release of vesicle contents. The National Institute of Mental Health contributed to Südhof’s funding, as his work involved studies of the transfer of chemical transmitters between neurons in the brain.
The Chemistry Prize, awarded to the three winners "for the development of multiscale models for complex chemical systems," recognizes the seminal efforts by Karplus, Levitt, and Warshel to develop computer programs powerful enough to simulate and predict chemical processes.
Evolving from hand-drawn diagrams and plastic models, chemistry has been one of the greatest scientific benefactors of the digital revolution. But even computer programs faced a critical obstacle when it came to simulating and predicting chemical reactions, which can occur with lightening speed: programs based on classical physics can show large molecules at rest but cannot capture the subatomic-scale dynamics of chemical reactions, while programs based on quantum physical equations, which are capable of treating electrons as both particles and waves, can model subatomic-scale reaction dynamics but use too much computer power to be applicable to entire molecules.
Building on a computer program designed by Karplus and Warshel to study the human retina and one Warshel and Levitt created to model enzyme reactions, a modern system incorporating both classical and quantum physics together was born. The program applies computationally demanding quantum physics only to the task of simulating the electrons and atomic nuclei directly involved in a chemical reaction, and uses classical physics to model the rest of the molecule. It would be impossible to model chemical processes at today’s high level of sophistication and speed without the foundational work done by the three laureates.
Karplus holds positions at Harvard University and the University of Strasbourg in France; Levitt is at Stanford University; and Warshel is at the University of Southern California. All three were supported with funding from the NSF.
Taken together, the work done by these six laureates demonstrates the continued leadership by Americans in critically important areas of science and technology, and provides an important reminder of the importance of Federal support for basic research. The American public can take pride in being both a sponsor and beneficiary of the progress made by the Nation’s finest scientists.
To learn more about the 2013 Nobel Prizes, visit: http://www.nobelprize.org/
Connor Schmidt is a Student Volunteer on the OSTP Communications Team