Artur Harden Chemist Date of Birth: 02.10.1865 Country: USA

1. Biography of Arthur Harden
2. Education and Early Career
3. Contributions and Nobel Prize
4. Later Life and Legacy

Biography of Arthur Harden

Arthur Harden, an English biochemist, was born in Manchester. He was the third of nine children and the only son of Albert Tyas Harden, a businessman, and Eliza (née McAllister) Harden. His parents were devout sectarians who raised their children in a religious and puritanical atmosphere, where even the celebration of Christmas was condemned.

Education and Early Career

After receiving his primary education at Victoria Park School in Manchester, Harden enrolled at Tattenhall College in Staffordshire in 1877, where he completed his studies four years later. He then entered Owens College at the University of Manchester and graduated with a Bachelor's degree in Chemistry in 1885. In the following year, Harden was awarded a scholarship, which he used to further his studies in Germany from 1887 to 1888 under Otto Fischer at the University of Erlangen. There, he studied the properties of a chemical compound called nitrosonaphthylamine, and his work earned him a doctoral degree.

In the same year, Harden became a lecturer in chemistry at the University of Manchester, where he remained until 1897 when he was appointed as a chemist at the Jenner Institute of Preventive Medicine in London (later renamed the Lister Institute). Initially, he taught chemistry and microbiology but later developed an interest in the history of natural science. However, after a few years, he immersed himself again in research activities, particularly in the study of sugar fermentation. Harden published several articles on this topic starting from 1899, focusing on fermentation initiated by specific bacteria. He also investigated the fermentation of sugar by yeast cells, challenging the belief that intact and living cells were necessary to induce the process.

Contributions and Nobel Prize

Harden knew that German chemist Eduard Buchner had shown in 1896 that a liquid separated from yeast could cause fermentation even without the presence of live yeast cells. Buchner demonstrated that a component of the extract, which he named zymase, could break down sugar molecules. Harden continued this line of research and, in 1904, discovered that zymase consisted of two components, one of which passed through a filter while the other did not. He also found that fermentation ceased when he removed one of the components from the yeast extract, providing evidence that both components were necessary for effective functioning. Harden named one component zymase and the other component, which was non-proteinaceous, cozymase.

In 1905, Harden made his second groundbreaking discovery: the fermentation process required the presence of phosphate, composed of one phosphorus atom and four oxygen atoms. He observed that the rate of sugar breakdown and the production of carbon dioxide and alcohol gradually decreased over time. However, when he added phosphate to the solution, the fermentation activity dramatically increased. Based on these observations, Harden concluded that phosphate molecules interacted with sugar molecules, creating conditions for the enzymatic induction of fermentation. Furthermore, he discovered that phosphate, after detaching from the reaction products, remained free through a complex series of conversions.

Harden's work on the role of phosphate in fermentation contributed to the study of the phenomenon later known as intermediary metabolism, involving compounds formed during chemical reactions in living organisms. Many of these intermediates, including phosphate, functioned similarly to phosphorus, primarily participating in reactions and then regenerating until the chemical process was complete. His research on sugar fermentation provided a model for subsequent experimenters investigating the breakdown of carbohydrates in plants and human muscle tissue.

In 1929, Harden, together with Hans von Euler-Chelpin, was awarded the Nobel Prize in Chemistry "for investigation of the fermentation of sugar and fermentative enzymes." In his presentation speech, member of the Royal Swedish Academy of Sciences, H.G. Sederbaum, noted that both Harden and Euler-Chelpin expanded and refined the results of Eduard Buchner's earlier work. He concluded, "The interest of specialists in studying the mechanisms of complex reactions of sugar fermentation allowed important conclusions to be drawn about the fundamental pathways of carbohydrate metabolism in plants and animals."

Later Life and Legacy

The following year after receiving the Nobel Prize, Harden retired as the director of the Lister Institute and dedicated the next ten years entirely to scientific research. In 1900, he married Georgina Sydney Bridge, originally from Christchurch, New Zealand. They did not have any children. Due to worsening nervous disorders over several years, Harden passed away on June 17, 1940, at his home in Bourne End, Buckinghamshire.

Harden was a reserved individual with a dry sense of humor. According to Frederick Gowland Hopkins, "As an experimenter, Harden possessed accuracy in observations, clarity of thought, and the ability to analyze experiment results and evaluate their significance." In 1926, Harden was knighted and, in addition to the Nobel Prize, he was awarded the Davy Medal of the Royal Society of London (1935). He received honorary degrees from the University of Manchester, the University of Liverpool, and the University of Athens.