Konrad Bloch

Konrad Emil Bloch, the German-born American biochemist who shared the 1964 Nobel Prize in Physiology or Medicine for working out how the body makes cholesterol, died in Burlington, Massachusetts, on October 15, 2000. He was eighty-eight. He was born on January 21, 1912, in Neisse, in the Prussian province of Silesia (now Nysa, Poland), into a Jewish family. He studied chemistry at the Technical University of Munich from 1930 to 1934. As Nazi persecution of Jews intensified, he left Germany in 1934 for a research institute in Davos, Switzerland, and in 1936 he emigrated to the United States. At Columbia University he earned a doctorate in biochemistry in 1938 and joined the faculty, working in the pioneering laboratory that used isotopes to trace molecules through living systems. He moved to the University of Chicago in 1946 and in 1954 to Harvard University, where he held the Higgins professorship of biochemistry until 1982. His great achievement was to follow the carbon atoms of cholesterol back to their source. Using labeled acetate in rats and in bread mold, he and his colleagues showed that the body builds cholesterol from simple two-carbon units through a long chain of steps, passing through squalene on the way. He helped show that acetyl coenzyme A is converted into mevalonic acid and then into the building blocks of squalene. He also found that bile acids and a female sex hormone are made from cholesterol, work that pointed to cholesterol as the parent of all steroids. He shared the Nobel Prize with Feodor Lynen; his Nobel lecture was titled "The Biological Synthesis of Cholesterol." He received the National Medal of Science in 1988 and was elected to the National Academy of Sciences, the American Academy of Arts and Sciences and the American Philosophical Society. After leaving Harvard he held an eminent scholar chair at Florida State University. He and his wife, Lore Teutsch, who met in Munich, married in 1941 and lived for decades in Lexington, Massachusetts. They had two children. He loved skiing, tennis and music. He died of congestive heart failure.