title: Historical article: Titration studies and the structure of DNA.
abstract: During the period of 1946-1956 ideas on the structure of the nucleic acids, especially DNA, were profoundly influenced by physico-chemical studies and, in particular, by electrometric titration studies pioneered by J. Masson Gulland and D.O. Jordan. It was eventually conclusively inferred when such studies had been sufficiently refined that: in DNA, the only hydrogen bonding that occurred was between the 1:6 amino groups of adenine and cytosine, and the -NH-CO "enolic" groups of thymine and guanine; the polynucleotide chains of DNA were not branched (or interrupted); and the internally hydrogen-bonded double-helical structure was stable both in aqueous solution and in the fibrous state.
authors.affiliation: Exeter College, Oxford OX1 3DP, UK. arthur.peacocke@theology.oxford.ac.uk
authors.forename: Arthur
authors.initials: A
authors.lastname: Peacocke
mesh_terms: D004247:DNA / Q000737:chemistry* / Q000266:history; D004563:Electrochemistry / Q000266:history; D049673:History, 20th Century; D006860:Hydrogen Bonding; D015394:Molecular Structure; D009690:Nucleic Acid Conformation; D012996:Solutions
chemical_list: D012996:Solutions; D004247:DNA