Ludwig Karl Martin Leonhard Albrecht Kossel (German pronunciation: [ˈalbʁɛçt ˈkɔsl̩] ; 16 September 1853 – 5 July 1927) was a German biochemist and pioneer in the study of genetics. He was awarded the Nobel Prize for Physiology or Medicine in 1910 for his work in determining the chemical composition of nucleic acids, the genetic substance of biological cells.
Kossel isolated and described the five organic compounds that are present in nucleic acid: adenine, cytosine, guanine, thymine, and uracil. These compounds were later shown to be nucleobases, and are key in the formation of DNA and RNA, the genetic material found in all living cells.
Kossel was an important influence on and collaborator with other important researchers in biochemistry, including Henry Drysdale Dakin, Friedrich Miescher, Edwin B. Hart, and his professor and mentor, Felix Hoppe-Seyler. Kossel was editor of the Zeitschrift für Physiologische Chemie (Journal of Physiological Chemistry) from 1895 until his death. Kossel also conducted important research into the composition of protein, and his research predicted the discovery of the polypeptide nature of the protein molecule.
The Albrecht Kossel Institute for Neuroregeneration at the University of Rostock is named in his honor.
Kossel was born in Rostock, Germany as the son of the merchant and Prussian consul Albrecht Karl Ludwig Enoch Kossel and his wife Clara Jeppe Kossel. As a youth, Kossel attended the Gymnasium at Rostock, where he evidenced substantial interest in chemistry and botany.
In 1872, Kossel attended the University of Strassburg to study medicine. He studied under Felix Hoppe-Seyler, who was head of the department of biochemistry, the only such institution in Germany at the time. He attended lectures by Anton de Bary, Waldeyer, August Kundt, and Baeyer. He completed his studies at University of Rostock, and passed his German medical license exam in 1877.
Early research and collaboration
After completing his university studies, Kossel returned to the University of Strassburg as research assistant to Felix Hoppe-Seyler. At the time, Hoppe-Seyler was intensely interested in research concerning an acidic substance that had first been chemically isolated from pus cells by one of his former students, Friedrich Miescher, in 1869. Unlike protein, the substance contained considerable amounts of phosphorus, but with its high acidity, it was unlike any cellular substance that had yet been observed.
Kossel showed that the substance, called "nuclein", consisted of a protein component and a non-protein component. Kossel further isolated and described the non-protein component. This substance has become known as nucleic acid, which contains the genetic information found in all living cells.
Isolation and description of nucleobases
In 1883, Kossel left Strassburg to become Director of the Chemistry Division of the Physiological Institute at the University of Berlin. In this post, he succeeded Eugen Baumann and worked under the supervision of Emil du Bois-Reymond.
Kossel continued his previous work on the nucleic acids. During the period 1885 to 1901, he was able to isolate and name its five constituent organic compounds: adenine, cytosine, guanine, thymine, and uracil. These compounds are now known collectively as nucleobases, and they provide the molecular structure necessary in the formation of stable DNA and RNA molecules.
Research into the chemical composition of protein
In 1895, Kossel was professor of physiology as well as director of the Physiological Institute at the University of Marburg. Around this time, he began investigations into the chemical composition of proteins, the alterations in proteins during transformation into peptone, the peptide components of cells, and other investigations.
In 1896, Kossel discovered histidine, then worked out the classical method for the quantitative separation of the "hexone bases" (the alpha-amino acids arginine, histidine, agmatine and lysine). He was also the first to isolate theophylline, a therapeutic drug found naturally in tea and cocoa beans.
In 1901, Kossel was named to a similar post at Heidelberg University, and became director of the Heidelberg Institute for Protein Investigation. His research predicted the discovery of the polypeptide nature of the protein molecule.
The processes of life are like a drama, and I am studying the actors, not the plot. There are many actors, and it is their characters which make this drama. I seek to understand their habits, their peculiarities.
Kossel was awarded the Nobel Prize in Physiology or Medicine in 1910 for his research in cell biology, the chemical composition of the cell nucleus, and for his work in isolating and describing nucleic acids. The award was presented on 10 December 1910.