Fischer, Emil (1852-1919) was a German chemist who did a wide range of research on organic substances such as sugars, enzymes, and proteins. He won the 1902 Nobel Prize in chemistry for his synthesis of sugars and purines.

Fischer was born in Euskirchen, near Bonn. He had five older sisters. His father was a successful merchant. For a time, Fischer worked in the family business, but it became clear that his interest and aptitude were for science. In 1871, he entered the University of Bonn to study chemistry. In 1872, he transferred to the University of Strasbourg, and he received his Ph.D. degree from that institution in 1874. For his doctorate, Fischer did research on dyes.

Fischer married Agnes Gerlach in 1888, and the couple had three sons. Fischer's wife died in 1895. Two sons were killed in World War I (1914-1918).

Fischer built chemical compounds that duplicate those of naturally occurring sugars and determined the molecular structure of the sugars. He also did basic research on dyes, proteins, enzyme actions, and purine derivatives, such as uric acid and caffeine. His research led to the development of synthetic drugs derived from barbituric acids, which were used to treat insomnia and anxiety.

Fischer was the first person to suggest the “lock and key” model of enzyme action. This theory states that an enzyme and its substrate (a substance upon which it acts) fit together like a lock and key and result in the “unlocking” of a biochemical reaction. This was the first attempt to explain why enzymes function as efficiently and specifically as they do.

In addition to his lab work, Fischer was a university instructor and department chair. He taught chemistry at the universities of Strasbourg, Munich, Erlangen, and Würzberg before accepting a post as the chair of chemistry at the University of Berlin in 1892. He remained on the faculty of the University of Berlin until his death in 1919.

Fischer helped to create a number of private research institutes, including the Kaiser Wilhelm Institute for Chemistry, the Kaiser Wilhelm Society, and the Kaiser Wilhelm Institute for Coal Research.

In 1870's, Fischer discovered a substance called phenylhydrazine, which he would later use in his research on sugars.

Fischer died in July 1919. Some sources say he died of cancer, but others say that he committed suicide, exhausted by work and deeply depressed by the deaths of two of his sons during World War I. After his death, the German Chemical Society instituted the Emil Fischer Memorial Medal in his honor.

Fischer's only surviving son, Herman Otto Laurenz Fischer, became a distinguished organic chemist and a professor of chemistry at the University of California in Berkeley. In 1952, this son dedicated the Emil Fischer Library at the University of California. The facility houses Fischer's collected works, including the manuscript for his unfinished autobiography (Aus meinem Leben, or Out of My Life), his research files, and his World War I correspondence.