Medicine: 1910

Kossel, Albrecht, pronounced KAWS uhl, AHL brecht (1853-1927), a German biochemist, won the 1910 Nobel Prize for physiology or medicine for his contributions to cell chemistry. His greatest interests were the study of proteins and the composition of the cell nucleus.

Proteins are an essential part of the diet. They are chemicals made up of smaller units called amino acids, compounds that contain carbon, hydrogen, oxygen, and nitrogen. The nucleus is the central part of the living cell that contains genetic material.

With the use of hydrolysis (a chemical process in which a compound is broken down and changed into other compounds by taking up the elements of water) and other methods, Kossel and his students discovered the substances thymine and cytosine, two components of a nucleic acid. Nucleic acids are complex molecules found in all cells that play a fundamental part in the chemistry of life. There are two types of nucleic acid: deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). Thymine and cytosine are components of DNA. Kossel also discovered the amino acid histidine, the antisepticthymic acid, and a component of nucleic acid called adenine.

Kossel was born in Rostock, Germany. He graduated from the University of Strasbourg in 1878. In 1883, he became the director of the chemical division of the Physiological Institute in Berlin. In 1895, he went to Marburg in Hesse as professor of physiology and director of the Institute for Physiology. He became head of the Physiological Institute in Heidelberg in 1901.