Euler-Chelpin, Hans von (1873-1964)

Swedish biochemist

Hans von Euler-Chelpin described the role of enzymes in the process of fermentation and also researched vitamins, tumors, enzymes, and coenzymes. He was an important contributor in the discovery of the structure of certain vitamins. In 1929, he shared the Nobel Prize in chemistry with Arthur Harden for their research on the fermentation of sugar and enzymes. Euler-Chelpin's research has far-reaching implications in the fields of nutrition and medicine.

Hans Karl Simon August von Euler-Chelpin was born in Augsburg in the Bavarian region of Germany on February 15, 1873, to Rigas, a captain in the Royal Bavarian Regiment, and Gabrielle (Furtner) von Euler-Chelpin. His mother was related to the Swiss mathematician Leonhard Euler. Shortly after his birth, Euler-Chelpin's father was transferred to Munich and Euler-Chelpin lived with his grandmother in Wasserburg for a time. After his early education in Munich, Würzburg, and Ulm, he entered the Munich Academy of Painting in 1891 intending to become an artist. Eventually, he changed his professional interest to science.

In 1893, Euler-Chelpin enrolled at the University of Munich to study physics with Max Planck and Emil Warburg. He also studied organic chemistry with Emil Fischer and A. Rosenheim, after which he worked with Walther Nernst at the University of Göttingen on problems in physical chemistry. This post-doctoral work in the years 1896 to 1897 was undertaken after Euler-Chelpin received his doctorate in 1895 from the University of Berlin.

The summer of 1897 was the first of several that Euler-Chelpin spent in apprentice roles in Stockholm and in Berlin. He served as an assistant to Svante Arrhenius in his laboratory at the University of Stockholm, becoming a privatdocent (unpaid tutor) there in 1899. Returning to Germany that summer, he studied with Eduard Buchner and Jacobus Van't Hoff in Berlin until 1900. His studies during this period centered on physical chemistry, which was receiving a great deal of attention at that time in both Germany and Sweden. Recognition came early to Euler-Chelpin for his work. He received the Lindblom Prize from Germany in 1898.

It was evident during this time that there were new opportunities in organic chemistry. The new equipment used to measure properties could be applied to the complexities of chemical changes that took place in organisms. Euler-Chelpin's interests, therefore, shifted to organic chemistry. He visited the laboratories of others working in the field, such as Arthur Hantzsch and Johannes Thiele in Germany and G. Bertrand in Paris. These contacts contributed to his developing interest in fermentation.

In 1902, Euler-Chelpin became a Swedish citizen and in 1906, he was appointed professor of general and organic chemistry at the University of Stockholm, where he remained until his retirement in 1941. By 1910, Euler-Chelpin was able to present the fermentation process and enzyme chemistry into a systematic relationship with existing chemical knowledge. His book, The Chemistry of Enzymes, was first published in 1910 and again in several later editions.

In spite of being a Swedish citizen, Euler-Chelpin served in the German army during World War I, fulfilling his teaching obligations for six months of the year and military service for the remaining six. In the winter of 1916–1917, he took part in a mission to Turkey, a German ally during World War I, to accelerate the production of munitions and alcohol. He also commanded a bomber squadron at the end of the war.

After the war, Euler-Chelpin began his research into the chemistry of enzymes, particularly in the role they played in the fermentation process. This study was important because enzymes are the catalysts for biochemical reactions in plant and animal organisms. An integral aspect of Euler-Chelpin's work with enzymes was to identify each substrate (the molecule upon which an enzyme acted) in the reaction. He succeeded in demonstrating that two fragments that split from the sugar molecule were disparate in energy. He further illustrated that the less energetic fragment, which is attached to the phosphate, is destroyed in the process. Apart from tracing the phosphate through the fermentation sequence, Euler-Chelpin detailed the chemical makeup of cozymase, a non-protein constituent involved in cellular respiration .

In 1929, Euler-Chelpin was awarded the Nobel Prize in chemistry, which he shared with Arthur Harden "for their investigations on the fermentation of sugar and of fermentative enzymes." The presenter of the award noted that fermentation was "one of the most complicated and difficult problems of chemical research." The solution to the problem made it possible, the presenter continued, "to draw important conclusions concerning carbohydrate metabolism in general in both the vegetable and the animal organism."

In 1929, Euler-Chelpin became the director of the Vitamin Institute and Institute of Biochemistry at the University of Stockholm, which was founded jointly by the Wallenburg Foundation and the Rockefeller Foundation. Although he retired from teaching in 1941, he continued research for the remainder of his life. In 1935, he had turned his attention to the biochemistry of tumors and developed, through his collaboration with George de Hevesy, a technique for labeling the nucleic acids present in tumors, which subsequently made it possible to trace their behavior. He also helped elucidate the function of nicotinamide and thiamine in compounds which are metabolically active.

Euler-Chelpin was twice married, each time to a woman who assisted him in his research. His first wife, Astrid Cleve, was the daughter of P. T. Cleve, a professor of chemistry at the University of Uppsala. She helped him in his early research in fermentation. They married in 1902, had five children, and divorced in 1912. Euler-Chelpin married Elisabeth, Baroness Ugglas in 1913, with whom he had four children. This marriage lasted for fifty-one years. A son by his first wife, Ulf Euler, later also won a Nobel Prize. His award was made in 1970 in the field of medicine or physiology for his work on neurotransmitters and the nervous system.

Euler-Chelpin was awarded the Grand Cross for Federal Services with Star from Germany in 1959. He also received numerous honorary degrees from universities in Europe and America. He held memberships in Swedish science associations, as well as many foreign professional societies. He is the author of more than eleven hundred research papers and over half a dozen books. Euler-Chelpin died on November 6, 1964, in Stockholm, Sweden.

Euler-Chelpin, Hans Karl August Simon von

(b. Augsburg, Germany, 15 February 1873; d. Stockholm, Sweden, 6 November 1964)

biochemistry.

Hans von Euler-Chelpin was the son of Rigas von Euler-Chelpin, a captain in the Royal Bavarian Regiment, and Gabrielle Furtner and was of the same family lineage as the Swiss mathematician Leonhard Euler. He attended schools in Munich, Würzburg, and Ulm, then from 1891 to 1893 studied art at the Munich Academy of Painting. His concern with the theory of colors caused him to become interested in the spectrum, and he turned his attention to science.

Euler-Chelpin enrolled at the then University of Berlin, where he studied physics under Emil Warburg and Max Planck and organic chemistry under Emil Fischer and A.Rosenheim. During the next two years he worked with W. Nernst in Göttingen. In the summer of 1897 he became an assistant to Svante Arrhenius in Stockholm, where he qualified as Privatdozent in physical chemistry at the University of Stockholm in 1898; he spent the summers of 1899 and 1900 with J. H. van’t Hoff in Berlin.

Until this time Euler-Chelpin had concentrated on physical chemistry, a subject being developed with much enthusiasm in Germany and Sweden. He now turned toward organic chemistry, visiting the laboratories of Arthur Hantzsch at Würzburg and Leipzig and Johannes Thiele at Strasbourg. He began research in the field at this time, partly in collaboration with his wife, Astrid Cleve. His visits to the laboratories of E. Buchner in Berlin and G. Bertrand in Paris reflected a developing interest in fermentation.

He became professor of general and organic chemistry at the University of Stockholm in 1906. All of his remaining professional work was carried out in Sweden, of which country he became a citizen in 1902. Nevertheless, in World War I he reported for service in the German army, serving in the artillery and, after 1915, in the air force. In the winter of 1916–1917 he was assigned to a military mission in Turkey to stimulate production of munitions and alcohol. He then returned to the air force, where he became commander of a bomber squadron. During this period he had an arrangement with the University of Stockholm that permitted him to compress his teaching activities into a half year. During World War II Euler-Chelpin again made himself available to Germany, but in a diplomatic capacity.

In 1929, the year in which he shared the Nobel Prize in chemistry with Arthur Harden for studies on fermentation, Euler-Chelpin became director of the Vitamin Institute and Institute of Biochemistry founded at the University of Stockholm through the joint support of the Kurt and Alice Wallenburg Foundation and the International Education Board of the Rockefeller Foundation. In 1941 he retired from teaching but continued his research activities almost to the end of his life. He was twice married: to Astrid Cleve (1902–1912), daughter of P. T. Cleve, professor of chemistry at the University of Uppsala, by whom he had five children; and Elisabeth, Baroness Ugglas (1913–1964), by whom he had four children. Both women were associated with him in some of his investigations. His son Ulf Svante von Euler shared the Nobel Prize in medicine or physiology in 1970.

Euler-Chelpin’s early interest in inorganic catalysis was soon transferred to biochemical studies and particularly to the enzymes associated with fermentation. His studies on the chemistry of plants led him to concentrate his interest on those fungi that lend themselves to the study of metabolic problems. His studies on vitamins were not really a diversion; most of this work contributed to the understanding of enzyme cofactors. His late work on cancer was also an extension of his work on enzymes.

The work for which Euler-Chelpin received the Nobel Prize in 1929 was closely associated with Buchner’s discovery that cell-free yeast juice was still able to ferment sugar, and the observation by Harden and Young that such juice, when passed through an ultrafilter, was separated into two fractions, neither of which alone had the power to ferment sugar but which on mixing again showed normal fermenting activity. Euler-Chelpin studied the low molecularweight fraction—named cozymase—for more than a decade, starting in 1923. By 1929 he and his associates, particularly K. Myrbäck and R. Nilsson, had clarified the role of cozymase in fermentation.

Harden had shown that phosphoric acid played a role in fermentation by giving rise to certain sugar phosphates. Euler-Chelpin and Nilsson developed the use of inhibitors whereby certain stages in enzymecatalyzed reactions can be blocked by use of a toxic substance, using fluoride to block that phase of fermentation in which cozymase functions. With Myrbäck, Euler-Chelpin showed that when glucose reacts with phosphoric acid it splits into two threecarbon fragments, one of which remains combined with phosphate. The two other fragments then combine to form glucose diphosphate, while the non-phosphorylated fragment undergoes further degradation. The reaction thereby shows that the sugar molecule undergoing fermentation splits into an energy-rich and an energy-poor fragment.

Euler-Chelpin also investigated the chemical nature of cozymase. Although cozymase is widely distributed in the plant and animal world, Euler-Chelpin and his associates found yeast to be the most practical source for its preparation. Starting with a crude extract having 200 units of activity, they concentrated this into a product having a specific activity of 85,000 units. This product corresponded to a nucleotide, containing sugar, a purine base, and a phosphate; it was clearly related to adenylic acid, which had been isolated by others from muscle. When Warburg showed nicotinamide to be a cofactor in erythrocytes, Euler-Chelpin tested for nicotinamide in cozymase with positive results. Soon thereafter Euler-Chelpin, Fritz Schlenk, and their co-workers showed the chemical structure of cozymase to be that of diphos phopyridine nucleotide (DPN).

In his work on vitamins, Euler-Chelpin assisted in clarifying the role of nicotinamide and thiamine (B₁) in metabolically active compounds. Somewhat earlier, in association with the Swiss chemist Paul Karrer, he had helped clarify the vitamin A activity of the carotenoid pigments. His work on tumors dealt particularly with the role of nucleic acids.

BIBLIOGRAPHY

I. Original Works.There is no collected bibliography of Euler-Chelpin’s more than 1,100 research papers, but see the listings in Poggendorff and in the author indexes of Chemical Abstracts. His Nobel Prize lecture, “Fermentation of Sugars and Fermentative Enzymes,” is available in Nobel Lectures, Including Presentation Speeches and Laureates’ Biographies, Chemistry, 1922–1941 (Amsterdam, 1966), pp. 144–155. His work is dealt with in detail in his books Grundlagen und Ergebnisse der Pflanzenchemie, 3 vols. (Brunswick, 1908–1909); Chemie der Hefe und der alkoholischen Gärung (Leipzig, 1915); Chemie der Enzym, 2 vols. (Munich-Wiesbaden, 1920–1927); Biokatalysatoren (Stuttgart, 1930); Homogene Katalyse (Stuttgart, 1931); Biochemie der Tumoren (Stuttgart, 1942), written with B. Skarzynski; Reductone, ihre chemischen Eigenschaften und biochemischen Wirkungen (Stuttgart, 1950); and Chemotherapie und Prophylaxe des Krebses (Stuttgart, 1962).

II. Secondary Literature. The best biographical sketch is Feodor Lynen’s obituary “Hans von Euler-Chelpin,” in Bayerische Akademie der Wissenschaften, Jahrbuch (1965), pp. 206–212. Also see R. Lepsius, “Hans Karl August von Euler-Chelpin zum Gedächtnis,” in Chemikerzeitung, 88 (1964), 933–936. Memoirs on his eightieth birthday are B. Eistert, “Hans von Euler-Chelpin zum 80 Geburtstag,” ibid., 77 (1953), 65; and W. Franke, “Zu Hans von Euler’s 80 Geburtstag,” in Naturwissen schaften, 40 (1953), 177–180. Also see the sketch accompanying his lecture in Nobel Lectures, pp. 156–158.

Aaron J. Ihde