Harden, Sir Arthur
- C. J. Martin
- , revised by Rachel E. Davies
Sir Arthur Harden (1865–1940)
Harden, Sir Arthur (1865–1940), chemist, was born in Manchester on 12 October 1865, the third of the nine children of Albert Tyas Harden, a Manchester manufacturer, and his wife, Eliza, daughter of John MacAlister, of Paisley. He was educated at Victoria Park School, Manchester, and later at Tettenhall College, Staffordshire. When he was sixteen years old he entered Owens College, Manchester, and studied chemistry under H. E. Roscoe. He graduated with first-class honours in chemistry in 1885 and embarked on an investigation of the action of silicon tetrachloride on aromatic amide-compounds under the guidance of Julius Berend Cohen. The results of this research were published by the Chemical Society and on its merits he was awarded the Dalton scholarship by the University of Manchester in 1886. The next two years were spent in Germany at the University of Erlangen where, under Otto Fischer, he prepared a nitrosonaphthylamine and investigated its properties. For his thesis on this subject he was awarded a PhD there.
In 1888 Harden was appointed a lecturer in chemistry at the University of Manchester. He took his responsibilities very seriously and for the next few years was preoccupied with teaching. He published a few papers on chemical topics and in 1896, with Roscoe, an interesting piece of historical research on the genesis of the atomic theory of John Dalton. From the study of Dalton's notebooks they concluded that it was his observations on the diffusion of gases which led him to formulate his atomic theory.
In 1897 Harden became chemist to the British Institute of Preventive Medicine (later known as the Jenner Institute) in London. He became head of the new department of biochemistry in 1907 and held this position until his retirement in 1930. In 1900 he married Georgina Sydney (d. 1928), elder daughter of Cyprian Wynard Bridge, of Christchurch, New Zealand; they had no children.
In 1912 Harden was appointed professor of biochemistry at the University of London. His first venture in biochemistry was to investigate the fermentation of sugar by various bacteria. The observations were necessarily limited to a quantitative study of the products, and what happened in the intermediate stages could be only imperfectly deduced from their nature and amounts. This research laid some of the foundations of bacterial chemistry. Shortly after Harden began work on bacterial metabolism, the German chemist Eduard Büchner (1860–1917) published experiments that concluded that living yeast was not, as maintained by Pasteur, essential for alcoholic fermentation, which could be induced by an expressed juice free from cells. Appreciating that if Büchner's contention were true, his yeast juice would provide material for the study of the conversion of sugar to alcohol step by step, Harden repeated his experiments and confirmed his results. Büchner thought that yeast juice contained an enzyme zymase, which broke up the sugar, but the chemical transactions involved in the conversion of one molecule of glucose into two each of alcohol and carbonic acid were mysterious.
For the next thirty years, Harden's principal researches were directed to the solution of the mystery. In this he was supported by able pupils and collaborators and notably by William John Young and Robert Robison. He discovered that in the transformation of sugars to alcohol and carbonic acid a complex series of reactions was involved and he made two fundamental discoveries. The first was that before any breakdown of the sugar molecules occurred, combination with phosphoric acid was necessary and that it was only after this preliminary phosphorylation that they became susceptible to disruption by the zymase in yeast. The second was that yeast juice contained not one but several enzymes which catalysed different reactions during the progress of conversion of sugar into alcohol and carbonic acid. One of these he presumed to activate the preliminary phosphorylation of the sugar molecules; another, a phosphatase, produced the separation of the phosphoric acid from the first products of the split sugar molecule, allowing it to combine with further sugar molecules. The essential part played by phosphorylation and dephosphorylation in the breakdown of sugars by yeast was soon found to apply to fermentation by other micro-organisms and provided a clue to the understanding of the conversion of glycogen into lactic acid in muscle during activity. Recognition of the significance of Harden's discovery constituted a turning point in the history of muscle chemistry.
During the First World War Harden suspended his work on alcoholic fermentation to study the chemistry of the two known water-soluble vitamins. Although he did not succeed in isolating these active principles, some of his observations on their properties became useful in the solution of nutritional problems confronting the armies, and they were a valuable contribution to the early knowledge of these accessory food factors.
Harden wrote two textbooks for students on chemistry while he was at Manchester. He also revised and edited the Treatise on Chemistry (1894) by Roscoe and Carl Schorlemmer. His most important monograph was Alcoholic Fermentation (1911). He contributed the article on this subject to Thorpe's Dictionary of Applied Chemistry, and one entitled 'Bacterial metabolism in the system of bacteriology' published by the Medical Research Council in 1930. For twenty-five years he was joint editor of the Biochemical Journal.
The importance of Harden's contributions to biochemistry was recognized by his election in 1909 as a fellow of the Royal Society, and by the award in 1929 of the Nobel prize for chemistry, which he shared with Hans von Euler-Chelpin. Honorary degrees were conferred on him by the universities of Manchester (1931), Liverpool (1935), and Athens (1937). In 1935 he was awarded the Davy medal of the Royal Society and he was knighted in 1936. Harden died at his home, Sunnyholme, Bourne End, Buckinghamshire, on 17 June 1940.
- The Times (18 June 1940)
- I. Smedley-Maclean, Biochemical Journal, 35 (1941), 1071–81
- F. G. Hopkins and C. J. Martin, Obits. FRS, 4 (1942–4), 3–14
- Journal of the Institute of Brewing (Sept 1940)
- R. Kohler, ‘The background to Arthur Harden's discovery of cozymase’, Bulletin of the History of Medicine, 48 (1974), 22–40
- CGPLA Eng. & Wales (1940)
- Bassano, whole-plate film negative, 1936, NPG [see illus.]
- Bassano, whole-plate film negatives, 1936, NPG
- photograph, repro. in Biochemical Journal (Nov 1941)
Wealth at Death
£7634 18s. 5d.: probate, 5 Sept 1940, CGPLA Eng. & Wales