Esther Lederberg, professor emeritus of microbiology and immunology at Stanford University, died of pneumonia and congestive heart failure on November 11. She was 83.
"She was a very keen observer and picked up biological phenomena that would have escaped the eyes and intellects of most other people," Stanley N. Cohen at Stanford University, who collaborated with Lederberg in the 1970s, told The Scientist.
Lederberg's 1951 discovery of lambda phage in the K-12 strain of E. Coli was a piece of luck facilitated by keen observation, Allan Campbell at Stanford University told The Scientist. She had "zapped" the strain with a large dose of ultraviolent light for another experiment and noticed "nibbled colonies," he said. Lederberg furthered examined these "nibbles" and isolated the culprit: lambda phage.
"It was a very big thing and became the premiere tool in molecular biology for many years," Richard Novick at New York University told The Scientist. Lamba phage was the first phage to be identified in the K-12 strain of E. Coli, which had been used in research since the 1920s. The discovery advanced the understanding of genetic organization and was a crucial tool for many Nobel Prize winners, including Alfred Hershey in 1969, according to Novick.
In 1952, Lederberg and her then-husband Joshua Lederberg developed replica plating, a technique that saves time and improves accuracy in the selection of mutants from a plate of hundreds of colonies. "It's been an extremely important tool in bacteria genetics ever since," said Novick.
The method was "brilliantly simple," friend and colleague Stanley Falkow at Stanford University told The Scientist in an email. "She thought of using ordinary velveteen from a yard goods store to serve as a kind of rubber stamp. The tiny fibers of the velveteen acted like hundreds of tiny inoculating needles." Lederberg even gave Falkow advice about what brand of velveteen worked best and which detergent to use.
In a eulogy at her memorial service last Thursday, Falkow told the story of his first encounter with Lederberg: "Her glasses were perched on her forehead and she held a plate of bacteria so close to her face that I feared her nose would touch the colonies," he said, noting that he would see her in the same pose many more times over the course of their friendship.
In the 1970s, Lederberg helped scientists more efficiently study microbes as the director of the newly created Plasmid Reference Center, where she named, organized, and distributed plasmids. A major challenge of this job, said Falkow, was mediating "contentious quarrels" among scientists about how plasmids were named.
"It has been said that a scientist would gladly wear the used underwear of a competitor rather than adopt their nomenclature," Falkow said in his eulogy. "But Esther always prevailed in bringing difficult investigators into line because she had the patience to wear them down." Lederberg maintained the Plasmid Reference Center until its closure in the late 1980s, according to Novick.
She retired from Stanford University in 1985 as one of the first female professors in the microbiology and immunology department. She had earned her masters degree in genetics there in 1946 and received a PhD from the University of Wisconsin in 1950.
She is survived by her second husband, Matt Simon, and her brother, Benjamin Zimmer.
Photo courtesy of Matt Simon
Links within this article:
Stanley N. Cohen
J. Lederberg, "Fifty Years Of Biochemical Genetics: A Tribute," The Scientist, September 1991.
J. Miller, "Interview with Stanley Falkow," The Scientist, April 7, 2003