DNA diffraction image (labeled as "Photo 51") taken by Rosalind Franklin and Raymond Gosling in May 1952, and the information that the DNA bases are paired. On 28 February 1953 Crick interrupted patrons' lunchtime at The Eagle pub in Cambridge to announce that he and Watson had "discovered the secret of life". Months earlier, in February 1953, Linus Pauling and Robert Corey proposed a model for nucleic acids containing three intertwined chains, with the phosphates near the axis, and the bases on the outside. Experimental evidence supporting the Watson and Crick model was published in a series of five articles in
Non-helical models of DNA structure The SBS structure was hypothetical, and was not based primarily upon physical evidence. It was created to provide a theoretical solution to the angular momentum problem in DNA replication, which Rodley believed to be otherwise unsolvable. The SBS structure is a modification of the original Watson-Crick structure where, instead of one fully right-handed helical twist every 10 base pairs, there is only a "half"-twist of 5 base pairs’ length, followed immediately by a half-twist in the "opposite" direction (that is, a left-handed half-twist, also of 5 base pairs’ length). This alternating pattern of right- and left-handed half-twists is repeated throughout