Denis Jordan

{{Short description|Anglo-Australian chemist}}

{{Use dmy dates|date=November 2019}}

{{Use Australian English|date=November 2019}}

{{Infobox officeholder

| honorific_prefix = Professor

| name = Denis Jordan

| honorific_suffix = {{postnominals|country=AUS|size=100%|AO|FAA|FRACI}}

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| office = Angas Professor of Chemistry, University of Adelaide

| term_start = 1958

| term_end = 1982

| birth_name = Denis Oswald Jordan

| birth_date = 23 September 1914

| birth_place = London, England

| death_date = {{Death date and age|1982|02|12|1914|09|23|df=yes}}

| death_place = St Georges, South Australia

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Denis Oswald Jordan (23 September 1914, London – 12 February 1982, St Georges, South Australia) was an Anglo-Australian chemist with a distinguished career as a researcher and lecturer in Chemistry at both University College Nottingham (1940–53) and the University of Adelaide, where he was Angas Professor of Chemistry from 1958 to 1982. Jordan also served as president of Australian Institute of Nuclear Science and Engineering from 1958 to 1962, and Royal Australian Chemical Institute from 1978 to 1979.

{{cite book |author= John Coates |title= Jordan, Denis Oswald (1914–1982) |chapter= Denis Oswald Jordan (1914–1982) |work= Australian Dictionary of Biography |publisher= National Centre of Biography, Australian National University |chapter-url= http://adb.anu.edu.au/biography/jordan-denis-oswald-12707 }} First published in Australian Dictionary of Biography, Volume 17, (MUP), 2007.

{{cite web |title= Jordan, Denis Oswald (1914-1982) |publisher= trove.nla.gov.au |url= http://trove.nla.gov.au/people/1469837?c=people }}

{{cite web |title= Jordan, Denis Oswald (1914 - 1982) |work= Biographical entry |publisher= Encyclopaedia of Australian Science |url= http://www.eoas.info/biogs/P000526b.htm }}

{{cite web |url= https://physsci.adelaide.edu.au/about/chemistry/history/angas-chair/ |title= Angas Chair of Chemistry |publisher= University of Adelaide }}

Whilst at Nottingham 'Doj' Jordan was a key member of the team whose research made important contributions to the eventual decoding of DNA in 1953. Jordan worked with John Masson Gulland, Michael Creeth and others on a series of experiments in 1947 which firstly created high quality DNA, then measured its viscocity, and finally demonstrated the hydrogen bonds within the molecule.Gulland JM, Jordan D. O., and Threlfall C. J., (1947) Deoxypentose nucleic acids. Part I. Preparation of the tetrasodium salt of the deoxypentose nucleic acid of calf thymus. J Chem Soc. 1947; 25: 1129-31JM Gulland; DO Jordan; HF Taylor; (1947) Deoxypentose nucleic acids; Part II electrometric titration of the acidic and the basic groups of the deoxypentose nucleic acid of calf thymus. J Chem Soc. 1947; 25:1131-41.Creeth, J.M., Gulland, J.M. and Jordan, D.O. (1947) Deoxypentose nucleic acids. Part III. Viscosity and streaming birefringence of solutions of the sodium salt of the deoxypentose nucleic acid of calf thymus. J. Chem. Soc. 1947,25 1141–1145 Their discoveries were ultimately acknowledged by James Watson as critical contributions even if he did at first dismiss them incorrectly: "...a rereading of J. M. Gulland's and D. O. Jordan's papers...made me finally realize the strength of their conclusion that a large fraction, if not all, of the bases formed hydrogen bonds to other bases."Watson, James D., 2012 The Annotated and Illustrated Double Helix, Ed. Gann & Witkowski, Simon & Schuster, New York (pp196-7)Watson J.D. & Crick F.H.C. The Structure of DNA, Cold Spring Harbor Symposia on Quantitative Biology, XVIII(1953)pp123-131) Gulland and Jordan's work was also acknowledged in the first papers concerning the decoding of DNA by Rosalind Franklin and Raymond Gosling.Franklin R.E. & Gosling R.F. Molecular Configuration in Sodium Thymonucleate, Nature, 25 April 1953 pp740-1 It has however been argued that the work of the Nottingham team was subsequently overlooked until commemorations were held in 2010 and 2017.Harding Steve, The forgotten scientist who paved the way for the discovery of DNA’s structure, The Conversation 13 November 2017 retrieved 20 November 2017.

Jordan continued to work at Nottingham University on deoxyribonucleic acid after the untimely death of Gulland in the Goswick rail crash in October 1947, but in 1953 he was appointed to a professorship in Adelaide where he arrived in 1954.{{fact|date=May 2020}}

In 1981, the University of Adelaide, named its physical and inorganic Chemistry building after Jordan.{{cite web |url=https://physsci.adelaide.edu.au/about/chemistry/history/ |title=History of Chemistry at the University of Adelaide |publisher=University of Adelaide |last=Gream |first=G.E. |date=October 2012 |accessdate=16 June 2016}}

In November 2017 a plaque was unveiled in the Trent Building at University of Nottingham commemorating the 70th anniversary of the "Discovery of Hydrogen Bonds in DNA by JM Creeth, DO Jordan and JM Gulland".{{fact|date=May 2020}}