Arthur Kornberg discovered DNA polymerase, earning the 1959 Nobel Prize in Physiology or Medicine.
DNA polymerase is an enzyme that builds a new DNA strand using an existing strand as a template. Kornberg and his team isolated DNA polymerase I from the bacterium Escherichia coli in 1956. The discovery provided a biochemical explanation for a central step in DNA replication.
Kornberg shared the 1959 prize with Severo Ochoa, who was recognized for discovering an enzyme involved in RNA synthesis. The Nobel citation referred to their discoveries of the mechanisms in the biological synthesis of ribonucleic acid and deoxyribonucleic acid.
RNA polymerase is a tempting alternative, but it was Ochoa’s RNA-related work that formed the other half of the award’s story. Reverse transcriptase and telomerase were discovered and characterized later, so they cannot be the enzyme Kornberg discovered for this prize.