- Person
- Joshua Lederberg
- Lived
- 1925–2008
- Field
- Microbiology, genetics
- From
- American
The story
Joshua Lederberg, the son of an Orthodox rabbi, grew up in Washington Heights in New York and entered Columbia University at fifteen. In 1946, on leave from medical school, he went to Yale University to work with Edward Tatum on a question most biologists considered pointless: could bacteria exchange genes? Bacteria were thought to reproduce only by splitting in two, passing identical copies of their genes to each daughter.
Lederberg and Tatum mixed two strains of E. coli, each unable to make certain nutrients. Some of the resulting bacteria could make all of them: they had combined genes from both parents. The process, which needs direct contact between cells, is now called conjugation. Lederberg was twenty-one. At the University of Wisconsin he went further. In 1951, with his student Norton Zinder, he showed that viruses that infect bacteria can carry pieces of DNA from one bacterium to another, a process called transduction. In 1952 he coined the word plasmid for genetic elements that live outside the main chromosome. In 1958, at thirty-three, he shared the Nobel Prize in Physiology or Medicine with Tatum and George Beadle.
These discoveries changed medicine’s understanding of infection. According to the U.S. National Library of Medicine, his work created a new understanding of how bacteria evolve and acquire new properties, including antibiotic resistance. Because bacteria can pass genes to one another directly, a resistance gene that appears in one microbe can spread through a population and even between species, which is why resistance can emerge and travel so quickly.
The same natural gene-transfer systems became the basis of biotechnology. The National Library of Medicine notes that transduction became the basis of genetic engineering in the 1970s, and plasmids became the standard vehicles for moving genes into bacteria, which is how human insulin and many other medicines are now produced.
Why it matters
Lederberg’s discovery explains how antibiotic resistance spreads, guiding efforts to preserve antibiotics, and supplied tools that genetic engineering uses to make medicines.
About Joshua Lederberg
Rabbi’s son who found at 21 that bacteria swap genes, explaining how antibiotic resistance spreads and laying groundwork for genetic engineering. Nobel Prize 1958.
More about Joshua Lederberg
Sources
- The Joshua Lederberg Papers: Biographical Overview National Library of Medicine, Profiles in Science
- Joshua Lederberg, Biographical NobelPrize.org
- Joshua Lederberg Wikipedia
Another act of tikkun olam. This is part of tikkun olam, the Jewish idea of repairing the world, and every one of us can add to it.