Cori, Carl Ferdinand (1896–1984),
and Gerty Theresa (1896–1957),
American biochemists. In 1936 the Coris discovered the activated intermediate glucose-1-phosphate that is often called the Cori ester. In 1942 they isolated and purified the enzyme responsible for catalyzing the conversion of glycogen to glucose-1-phosphate. In 1943 they achieved the test-tube synthesis of glycogen. Proof of the glucose-glycogen interconversion allowed them to formulate what is now known as the Cori cycle. Their discoveries led to a new understanding of hormonal influence on the interconversion of sugar and starches in the animal organism. In 1947, the Coris were awarded the Nobel Prize for Physiology or Medicine.