Joshua Lederberg, ForMemRS was an American molecular biologist known for his work in microbial genetics, artificial intelligence, and the United States space program. He was 33 years old when he won the 1958 Nobel Prize in Physiology or Medicine for discovering that bacteria can mate and exchange genes. He shared the prize with Edward Tatum and George Beadle, who won for their work with genetics.
Lederberg in New Delhi, India
Lederberg (right) receiving The National Medal of Science from George H. W. Bush.
Bacterial conjugation is the transfer of genetic material between bacterial cells by direct cell-to-cell contact or by a bridge-like connection between two cells. This takes place through a pilus. It is a parasexual mode of reproduction in bacteria.
Agrobacterium tumefaciens gall at the root of Carya illinoensis.