Nirenberg and Leder experiment acid. Oswald Avery discovered that the substance responsible for producing inheritable change in the disease-causing bacteria was neither a protein nor a lipid, rather deoxyribonucleic acid (DNA). He and his colleagues Colin MacLeod and Maclyn McCarty suggested that DNA was responsible for transferring genetic information. Later, Erwin Chargaff discovered that the makeup of DNA differs from one species to another. These experiments helped pave the way for the discovery of the structure of DNA. In 1953, with the help of Maurice Wilkins and Rosalind Franklin’s X-ray crystallography, James Watson and Francis Crick proposed DNA is structured as a double helix.
Francis Crick structure of DNA. Orgel also later worked with Crick at the Salk Institute for Biological Studies. Soon after Crick's death, there have been allegations about him having used LSD when he came to the idea of the helix structure of the DNA. While he almost certainly did use LSD, it is unlikely that he was doing that as early as 1953. In 1954, at the age of 37, Crick completed his Ph.D. thesis: ""X-Ray Diffraction: Polypeptides and Proteins"" and received his degree. Crick then worked in the laboratory of David Harker at Brooklyn Polytechnic Institute, where he continued to develop