Willstätter, Richard Martin

GERMAN CHEMIST
1872–1942

As a boy, Willstätter proved to be a gifted student and tried to attend the best schools in Germany. But since he was a Jew, he was denied admission and was forced to attend public school. After graduation he entered the University of Munich, where he established himself in the scientific community.

He studied the structure of cocaine, the subject of his 1894 doctoral thesis, and analyzed and synthesized such similar plant extracts as atropine and tropine. One of his teachers greatly disapproved of this line of work, and Willstätter soon turned his attention to quinone chemicals, which are the basis for many dyes, including aniline black. After spending several years as a research assistant in Germany, Willstätter joined the teaching staff of the University of Zurich as a professor in 1905. He became intrigued by chlorophyll and other pigments because of their extreme complexity and their intimate role in plant and animal life. To study these pigments, Willstätter revived the technique of chromatography , which had been introduced by Mikhail Tsvett (1872–1920) in 1906.

Before Willstätter began studying chlorophyll , scientists thought that each different shade of green in plants was created by a unique chlorophyll molecule. Working with the dried leaves from more than two hundred plants, Willstätter showed that there are two major types of chlorophyll found in land plants—the blue-green, or a type, and the yellow-green, or b type. Willstätter also discovered a similarity between chlorophyll and hemoglobin—the red pigment that carries oxygen through blood. Both chlorophyll and hemoglobin contain a ring-like structure surrounding a single atom, but chlorophyll contains a magnesium atom, while the hemoglobin molecule holds an atom of iron. This discovery was the first clue to magnesium's importance as a plant nutrient. Since then, agricultural fertilizers for magnesium-deficient soils have greatly increased crop yields. Willstätter also studied the chemistry of nongreen plant pigments, which give flowers and fruits their bright colors. As a result of Willstätter's research on plant pigments, he was awarded the Nobel Prize in chemistry in 1915.

In 1911 Willstätter had returned to Germany where his work was interrupted by World War I. His friend Fritz Haber (1868–1934) convinced him to help design an effective gas mask for German troops. In 1916 he succeeded his mentor Adolf von Baeyer as chemistry professor at the University of Munich, where he became interested in enzymes , a class of biological catalysts . Although he succeeded in obtaining pure enzyme samples, he tried to prove, incorrectly, that enzymes were not proteins.

In 1925 prejudice again interfered with Willstätter's career. When his university rejected a qualified Jewish scientist for a professorship, Willstätter resigned in protest. Willstätter was offered many industrial and university positions outside of Germany, but he preferred to live in Germany. He was forced into hiding when the Nazis targeted him for arrest. He was caught when he tried to escape to Switzerland, but was turned over to the Swiss authorities. Willstätter died in Switzerland in 1942.