BASIC INFORMATION
Ester Miriam Zimmer Lederberg was an American microbiologist and a pioneer in bacterial
genetics. She was born in Bronx, New York, United States on December 18, 1922. She died
on November 11, 2006 in California, United States at the age of 83. She was the eldest child
of David Zimmer and Pauline Geller Zimmer.
She pursued her degree in biochemistry at Hunter College in 1942, her master’s degree in
Genetics at Stanford University in 1944, and her PhD at the University of Wisconsin in the
year 1950.
MAJOR CONTRIBUTION
She was a major contributor in the field of biochemistry and microbiology. Ester and Joshua
Lederberg, her husband, were the first ones to describe replica plating—which is the process
of isolating antibiotic-resistant bacteria and viruses from the environment to prevent the
mutants from coming in contact with the drug designed to eradicate it.
While she was a PhD student in 1951, she first reported the discovery of the lambda phage,
and later provided a detailed description in a 1953 paper in the Journal Genetics. Lambda
bacteriophage is a bacterial virus which is widely used as a tool to study gene regulation and
genetic recombination. Its behavior aids scientists to have a better understanding of how
similar viruses work.
She also discovered the bacterial fertility factor, also known as F sex factor, which allows
genes to be transferred from one bacterium carrying the factor to another bacterium lacking
the factor by conjugation.
In 1976, she founded and directed the Plasmid Reference Center (PRC) located at the
Stanford School of Medicine, which aimed to develop a standard and consistent
nomenclature for bacterial plasmids.
AWARDS
Because of her passion and knowledge in academia, she received multiple awards such as
the 1956 Society of Illinois Bacteriologists: Pasteur Award;
A Fulbright fellowship in bacteriology to work at Melbourne University in Australia in 1959;
1969 American Cancer Society Dernham Postdoctoral Fellowship in Oncology (Senior
Fellowship);
Fellow of the American Association for the advancement of Science;
And the President of the Stanford Chapter of Sigma Xi.
SOCIAL
As a woman in the field of Science during the 20th century, she also experienced
discrimination. Her very own professor once advised her not to pursue her degree in
Biochemistry, because women usually struggled to get a career on that field. However, she
persisted and finished her undergraduate studies.
Just like many other female scientists, she was not given the credit that she deserved. She
was a victim of the “Matilda Effect”, a bias against acknowledging the achievement of those
women scientists whose works were attributed to their male colleagues. In Ester’s case, it
was her first husband, Joshua Lederberg.
In 1966, Ester and Joshua divorced. However, in 1993, she got remarried to Matthew Simon,
an engineer who made a collection of her previous works that were not given proper credit.
OUTRO
Because of the inspiring stories of women like Ester Lederberg, more work, at present, is
going into identifying the barriers to women’s participation in Science, like the stereotype that
women are innately unsuited to the work. Just like what Katy Steinmetz, a TIME
Correspondent, wrote on her article about Ester Lederberg, “Rewriting history is hard, but
telling stories from a new point of view can be a catalyst.”
