History of molecular biology Crick and Watson built physical models using metal rods and balls, in which they incorporated the known chemical structures of the nucleotides, as well as the known position of the linkages joining one nucleotide to the next along the polymer. At King's College Maurice Wilkins and Rosalind Franklin examined X-ray diffraction patterns of DNA fibers. Of the three groups, only the London group was able to produce good quality diffraction patterns and thus produce sufficient quantitative data about the structure. In 1948 Pauling discovered that many proteins included helical (see alpha helix) shapes. Pauling had deduced this structure from X-ray
James Watson his phage and other experimental research conducted at Indiana University, Statens Serum Institut (Denmark), CSHL, and the California Institute of Technology, Watson now had the desire to learn to perform X-ray diffraction experiments so he could work to determine the structure of DNA. That summer, Luria met John Kendrew, and he arranged for a new postdoctoral research project for Watson in England. In 1951 Watson visited the Stazione Zoologica 'Anton Dohrn' in Naples. In mid-March 1953, Watson and Crick deduced the double helix structure of DNA. Crucial to their discovery were the experimental data collected at Kings College — mainly