An illustration of the 3-D structure of Seneca Valley Virus-001. The structure of a virus that is harmless to normal human cells but an enemy of certain cancer cells has been determined by researchers using an x-ray beamline at the U.S. Department of Energy?s Advanced Photon Source (APS) at Argonne National Laboratory. This new knowledge may help drug designers tweak the pathogen enough so that it can attack other tumor subtypes. Using the University of Chicago?s BioCARS 14-ID beamline at the APS, the researchers from The Scripps Research Institute have, for the first time, solved the three-dimensional (3-D) structure of a virus, known as ?Seneca Valley Virus-001,? that can infect specific cancer cells.