Jim decided, I guess it was spring of ‘55 that he was going to go back to Cambridge. And I heard about the experimental resources there for X-ray diffraction on large structures, and I figured, you know, it was the place to go to try to answer the question about the symmetry of the isometric—of these spherical viruses. But Jim and Francis had already had, you know, an idea that isometric viruses would have to be built out of subunits and if they’re built out of identical subunits they would be arranged with some sort of symmetry. Actually, they—the story I recollect from Jim about where, you know, when he had gotten the idea again it was in this period at Cambridge when Bragg had declared a moratorium on the work on DNA structure. Jim said that he decided to try to build a model for water structure using the [John] Kendrew wire models. When he sort of put them together every natural structure is pentagonal dodecahedron. And looking at the symmetry of this was one of the sort of stimuli for thinking about what sort of arrangements, what sort of regular arrangements of objects in a closed-shell periphera were possible. So, actually I guess I had met Francis and Jim here at Cold Spring Harbor in—I think it must have been—it must have been the 1954 Cold Spring Harbor Symposia, when I first heard their ideas about the possible symmetry of isometric viruses which was, you know, part of the stimulus for going to Caltech and then giving up Caltech and going to Cambridge…

Donald Caspar, structural biologist and crystallographer, is a professor emeritus of Biological Sciences at the Institute of Molecular Biophysics at Florida State University in Tallahassee, Florida and is also a member of the National Academy of Sciences.

Born on January 8, 1927, he received his B.A. in Physics from Cornell University in 1950, and his his Ph.D. in Biophysics from Yale University in 1955. Caspar is interested in protein adaptability, virus assembly, protein plasticity and x-ray diffraction. He currently researches the mechanics of protein movements by executing structural studies.

He has attended many symposia at Cold Spring Harbor Laboratory, starting in 1961, and worked with Watson at Caltech and Harvard. He is a member of the National Academy of Science. Dr. Casper is a long-time friend and colleague of Dr. James D. Watson as well as many of the early pioneers in molecular biology, including Dr. Rosalind Franklin.