History of chemistry quantum mechanics were able to predict qualitatively some chemical features for biologically relevant molecules, they were, till the end of the 20th century, more a collection of rules, observations, and recipes than rigorous ab initio quantitative methods. This heuristic approach triumphed in 1953 when James Watson and Francis Crick deduced the double helical structure of DNA by constructing models constrained by and informed by the knowledge of the chemistry of the constituent parts and the X-ray diffraction patterns obtained by Rosalind Franklin. This discovery lead to an explosion of research into the biochemistry of life. In the same year, the
Non-helical models of DNA structure as evidence that the strands were plectonemically wound together ("i.e.," topologically linked). The publication of the Rodley structure produced a small but significant ripple of interest in the molecular biological community. However, the level of interest was sufficiently high so that Crick - by that time one of the world’s most influential scientists - publicly suggested that the SBS structure (whose existence he doubted) should be laid to rest by intentionally creating it. Then, he reasoned, its properties could be ascertained, and then shown to be abnormal with respect to the known properties of native DNA. An investigation by Stettler