Francis Crick his skills in the analysis of X-ray diffraction data for proteins, working primarily on ribonuclease and the mechanisms of protein synthesis. David Harker, the American X-ray crystallographer, was described as "the John Wayne of crystallography" by Vittorio Luzzati, a crystallographer at the Centre for Molecular Genetics in Gif-sur-Yvette near Paris, who had worked with Rosalind Franklin. After the discovery of the double helix model of DNA, Crick's interests quickly turned to the biological implications of the structure. In 1953, Watson and Crick published another article in "Nature" which stated: "it therefore seems likely that the precise sequence of the bases
Nucleic acid double helix common double helical structure found in nature, the double helix is right-handed with about 10–10.5 base pairs per turn. The double helix structure of DNA contains a "major groove" and "minor groove". In B-DNA the major groove is wider than the minor groove. Given the difference in widths of the major groove and minor groove, many proteins which bind to B-DNA do so through the wider major groove. The double-helix model of DNA structure was first published in the journal "Nature" by James Watson and Francis Crick in 1953, (X,Y,Z coordinates in 1954) based upon the crucial X-ray diffraction image