es of Health (1942-1953), he helped elucidate the reactions leading to the formation of two important coenzymes: flavin adenine dinucleotide (FAD) and diphosphopyridine nucleotide (DPN). During the summer of 1953, Kornberg enrolled in a microbiology course offered by Cornelius van Niel in Pacific Grove, California. Kornberg recently accepted a position as chair of the Department of Biochemistry at the Washington University School of Medicine in St. Louis, and he felt the need for a more formal instruction in the subject. Kornberg became intrigued with bacteria as a source of enzymes for his research. In particular, he became interested in biosynthetic pathways for the building blocks of deoxyribonucleic acid (DNA). It was also in 1953 that James Watson and Francis Crick reported their discovery that DNA is a pair of chains spiraling about each other-a double helix. Within two years of Watson and Cricks historic report, Kornberg had found, in juices extracted from cells, an enzyme that synthesizes the huge chains of DNA from simple blocks. But it was not until 1956 that Kornbergs interest in the replication of DNA became the focus of his research. It was after the enzyme that assembles the nucleotide building blocks into a DNA chain was already in his hands. Much of his research during 1953 and 1954 dealt with purification of the enzymes that synthesize the precursors of DNA. By 1954, Kornbergs team had firmly established how the nucleotides are synthesized. The next step was to study how they are assembled into DNA or RNA. Initial experiments with extracts from animal cells were unsuccessful, and Kornberg turned to extracts from the bacterium Escherichia coli (E. coli). This was the first major discovery his team had made, and was the chemical catalyst responsible for the synthesis of DNA. They discovered the enzyme in the common intestinal bacterium Escherichia coli, and Kornberg called it DNA polymerase. This was an important discov...
