Kurt Guenter Stern

Background

Kurt was was born on September 19, 1904 in Tilsit, Germany, the son of John Kasper Stern and Sonia Goldberg.

Education

After studying in Berlin at the Werner-Siemens Realgymnasium, he attended the Friedrich-Wilhelms University in Berlin, where he received the Ph. D. in 1930. His doctoral work was done at the pathological institute of the university in the laboratory of Hans Kuhlman, the research dealing with proteases (protein-splitting enzymes) extracted from spleens of cattle.

Career

Upon completion of his doctorate, Stern received a fellowship sponsored by Carl Duisberg, a prominent German chemical industrialist. The fellowship enabled Stern to spend the next year in the United States, where he worked in the laboratory of Leonor Michaelis at the Rockefeller Institute for Medical Research. This work dealt with the influence of heavy metals such as copper, mercury, iron, manganese, and selenium on the proteolytic action of tissue extracts on proteins such as casein, gelatin, and serum albumin. He showed that iron and manganese had an activating effect while mercury, copper, and selenium were inhibitory.

From 1931 to 1933 Stern worked as research chemist in the physiological chemistry laboratory of the Rudolf Virchow Hospital in Berlin, where he continued his studies on proteases. After the Nazis came to power in 1933, he was able to obtain a post as a visiting guest scientist in the Courtauld Institute of Biochemistry of the Middlesex Medical School in England.

By spectroscopic study, Stern and Holiday identified a fragment of the group as an alloxazine derivative. This led to an elucidation of the chemical structure of the flavins and enabled Richard Kuhn in Heidelberg and Paul Karrer in Zurich independently to synthesize an extensive series of such compounds, leading to recognition of riboflavin as the substance then known as vitamin B2.

In 1935 Stern was appointed lecturer in physiological chemistry at Yale University. In 1937-1938 he was Alexander Brown Coxe research fellow and then became assistant professor at Yale until 1942. In that year he became chief chemist with the Overly Biochemical Research Foundation. Two years later he was made adjunct professor of biochemistry at the Polytechnic Institute in Brooklyn, a position he held until his death while on a lecture tour in London.

He had become a naturalized American citizen in 1946.

In 1926 Warburg observed the linkage of respiratory and fermentation processes by a chemical reaction that was eventually referred to as the Pasteur reaction. Splitting of sugar by free oxygen in the presence of heavy-metal catalysts was inhibited by certain reagents leading, during the next two decades, to the search for the iron-containing substance associated with the Pasteur reaction.

In 1941 Stern and Melnick reported the spectrum of the carbon monoxide derivative of the Pasteur enzyme in the retina and in yeast. However, Stern's effort to shed further light on the Pasteur effect was unfruitful since the Pasteur reaction would prove to be more complex than had been surmised. During much of his career, Stern was also interested in enzymes known as catalases.

These enzymes have a role in cellular metabolism since they catalyze the breakdown of hydrogen peroxide - formed in certain steps in cellular respiration - to water and molecular oxygen. He first isolated catalases from blood cells and from animal liver and directed a large amount of research toward understanding their composition and properties.

He died on September 19, 1904 in London.

Achievements

• Kurt Guenter Stern was well-known as the co-author of such famous works as Allgemeine Chemie der Enzyme (1932) and Biological Oxidation (1939). His research fields included the structure of genes, techniques of ultracentrifugation, and electrophoresis. Besides, he was chairman of the chemists' division of the United Jewish Appeal.

Works

More photos

• book

  • Allgemeine Chemie der Enzyme (Vol-1) (German Edition)

    (This book was digitized and reprinted from the collection...)

  • Biological Oxidation

Views

Stern was deeply interested in the application of scientific knowledge and obtained patents on the electrophoretic analysis of colloidal liquids and biological fluids; on the decolorization of soybean oil; and for the capacitron, a device for sterilizing food by destroying bacteria and viruses through disruptive effects on the deoxyribonucleic acid (DNA) of their cells or molecules.

In his latest years he believed himself on the verge of successful results in the treatment of cancerous tissues by introduction of radioisotopes of rare earth compounds.

Toward the end of his career Stern began to give attention to the chemistry of nucleoproteins - proteins associated with nucleic acids, the carriers of genetic information in the cell.

His research was aimed toward understanding of the size and shape of chromosomal nucleoproteins and their bearing on gene structure, an objective which was, however, not readily responsive to the chemical approach but would ultimately be resolved by a combination of chemical information interpreted through X-ray crystallography.

Connections

On December 24, 1931, Stern married Else E. Jacobi, who worked with her husband for a time and published several papers with him. They had one son.

Father:

John Kasper Stern

Mother:

Sonia Goldberg

Wife:

Else E. Jacobi

associate:

Joseph L. Melnick

associate:

Ensor R. Holiday