ESTHER MIRIAM ZIMMER LEDERBERG (December 18, 1922 – November 11, 2006) was an American microbiologist and a pioneer of bacterial genetics . Notable contributions include the discovery of the bacterial virus λ , the transfer of genes between bacteria by specialized transduction , the development of replica plating , and the discovery of the bacterial fertility factor F (F plasmid).
Lederberg also founded and directed the now defunct Plasmid Reference Center at Stanford University, where she maintained, named, and distributed plasmids of many types, including those coding for antibiotic resistance, heavy metal resistance, virulence , conjugation , colicins , transposons , and other unknown factors.
* 1 Early years
* 2 Contributions to microbiology and genetics
* 2.1 λ bacteriophage and specialized transduction * 2.2 Bacterial Fertility Factor F * 2.3 Replica plating * 2.4 Later contributions
* 3 Professional honors * 4 Professional challenges: gender discrimination
* 5 Other interests
* 5.1 Music
* 5.2 Literature
* 6 Notable papers * 7 References * 8 External links
Esther Miriam Zimmer was the first of two children born in the Bronx
, New York, to David Zimmer and Pauline Geller Zimmer. Her brother,
Benjamin Zimmer, followed in 1923. A child of the
Zimmer thrived academically. She attended Evander Childs High School
in the Bronx, receiving honors for French and graduating at the age
of 16. In college, Zimmer initially wanted to study French or
literature, but she switched her field of study to biochemistry
against the recommendation of her teachers, who felt women struggled
to get a career in the sciences. She worked as a research assistant
New York Botanical Garden
After her graduation from Hunter, Zimmer went to work as a research
assistant to Alexander Hollaender at the Carnegie Institution of
Cold Spring Harbor Laboratory ), where she continued
to work with N. crassa as well as publishing her first work in
genetics. In 1944 she won a fellowship to
Lederberg next went to the
University of Wisconsin
CONTRIBUTIONS TO MICROBIOLOGY AND GENETICS
Lederberg remained at the
University of Wisconsin
λ BACTERIOPHAGE AND SPECIALIZED TRANSDUCTION
Her 1950 lambda phage paper led to an understanding of specialized transduction.
A permanent exhibit in the "DNAtrium" of The Eli and Edythe L. Broad
Massachusetts Institute of Technology
BACTERIAL FERTILITY FACTOR F
The Fertility Factor (also known as F Factor) is a bacterial DNA sequence that allows a bacterium to produce a sex pilus necessary for conjugation. The sequence contains 20 tra (for "transfer") genes and a number of other genetic sequences responsible for incompatibility, replication, and other functions. The F factor is carried on an episome, which can either exist as an independent plasmid or integrate into the bacterial cell's genome.
Esther Lederberg's discovery of F stemmed directly from her experiments to map the location of lambda prophage on the E. coli chromosome by crosses with other E. coli strains with known genetic markers. When some of the crosses failed to give rise to recombinants, she suspected that some of her E. coli strains had lost a "fertility factor." In her own words:
In terms of testing available markers ... the data showed that there was a specific locus for lysogenicity. ... In the course of such linkage studies,...one day, ZERO recombinants were recovered....I explored the notion that there was some sort of 'fertility factor' which if absent, resulted in no recombinants. For short, I named this F. A number of experiments were designed to clarify these observations.
Although there were other less efficient forerunners to the methodology (such as paper, or multipronged arrays using wire brushes, toothpicks, etc.), the problem of reproducing bacterial colonies en masse in the same geometric configuration as on original agar plate was first successfully solved by replica plating, as implemented by Esther M. Zimmer Lederberg.
Scientists had been struggling for a reliable solution for at least a
Allan Campbell, Eugene Nester and
Stanley Falkow all recount how
Who successfully implemented the technique? Here Esther at least refined the process considerably. I remember (from her and others) that SHE WAS THE ONE WHO WENT TO THE FABRICS STORE AND SELECTED VELVET OF THE BEST THICKNESS, PILE, ETC. to give the cleanest prints.
Eugene Nester said:
I wanted to respond to your question about replica plating and who really invented it. I think it will be very difficult to answer that question in a convincing way. That technique was developed before I ever knew the Lederbergs ... I do know that Esther in all likelihood was responsible for getting the technique to actually work. She emphasized to me how important it was to use a particular kind of Italian velvet (or was it velveteen actually), so in my own mind I believe she was the key person in taking the idea to actual practice.
In Falkow's case, this happened a few years after she first published the replica plating paper. At the memorial for Esther Lederberg, he spoke of the impact of replica plating, and his feelings upon meeting the originator of the technique:
It was brilliantly simple: creative discoveries often are. 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 inocculating needles. The pad was carefully kept in the same orientation and used to inocculate a series of agar plates containing different media containing antibiotics or supplemented with essential nutrients such as amino acids and vitamins. Esther and Joshua used this technique as an indirect selective method to prove the spontaneous origin of mutants with adaptive advantages. ...
All of these things foreshadowed our first meeting and I was appropriately in awe of her. I was just starting to use replica plating in my own work and ESTHER IMMEDIATELY TOLD ME WHAT BRAND OF VELVETEEN TO LOOK FOR AND TO BE SURE TO WASH THE VELVETEEN BEFORE I USED THEM AND EVEN WHAT DETERGENT TO USE TO WASH THEM.
At first, plasmids were of great interest due to their ability to confer inheritable resistance to antibiotics, thus were referred to as "R-Factors" or "R plasmids". As time passed, the nomenclature was changed to "Plasmids" (in general) to take into account other factors in addition to antibiotic resistance, such as genes for specific activity (gal, lac, ara, etc.) and temperature sensitivity. (For example, plasmid pSC304 used Kretschmer's protocol to establish temperature sensitivity. See P. J. Kretschmer and S. N. Cohen, 1977, J. Bacteriol., 130, 888-899.)
The PRC coordinated closely with the members of the Plasmid Nomenclature Committee (Royston Clowes, Stanley N. Cohen, Rob Curtiss III, Naomi Datta, Stanley Falkow, and Richard P. Novick), assigning prefixes to plasmids, and numbers to Insertion Sequences and Transposons.
She retired from her position in the Stanford Department of
* 1956 Society of Illinois Bacteriologists: Pasteur Award (with
Fulbright Fellowship in bacteriology to work at Melbourne
University in Australia.
American Cancer Society Dernham Postdoctoral Fellowship in
Oncology (Senior Fellowship)
* Fellow of the
American Association for the Advancement of Science
* President of the Stanford Chapter of
In 1985, Lederberg was honored as an emeritus professor in microbiology and immunology at Stanford University.
A black granite block shows a photograph of
PROFESSIONAL CHALLENGES: GENDER DISCRIMINATION
Stanley Falkow said of
Lederberg was excluded from writing a chapter in the 1966 book Phage and the Origins of Molecular Biology, a commemoration of molecular biology. According to the science historian Prina Abir-Am, her exclusion was "incomprehensible" because of her important discoveries in bacteriophage genetics. Abir-Am attributed her exclusion in part to the sexism that prevailed during the 1960s.
Luigi Luca Cavalli-Sforza
Allan Campbell noted the injustice of Stanford’s attitude toward women scientists in a letter of recommendation for Esther Lederberg, written in 1971: “I think she is a definite asset to the University and merits promotion according to the normal customs of your department (i.e., that your Committee on Women’s Promotions should recommend advancement on the same time schedule as a Committee of Men’s Promotions would advance a male scientist).“
A lifelong musician, Lederberg was a devotee of early music . She was one of the founding members of the Mid-Peninsula Recorder Orchestra (affiliated with the San Francisco Early Music Society) in 1962, serving as its president for several years. At the memorial held for Dr. Lederberg at Stanford University, Frederick Palmer, musical director of the Mid-Peninsula Recorder Orchestra, spoke of Esther’s joy in this music, and her dedication to the MPRO:
One of the frustrations of anyone directing a musical ensemble made up of volunteers is wondering who will show up for rehearsals and if all of the parts will be adequately covered. I never had to worry about Esther. Even after her health began to fail and she was required to use a walker, Esther seldom missed one of the orchestra's meetings, and she insisted on playing in the concerts that the orchestra presented despite her limited mobility.
She loved symphonic music, opera, and the operettas of Gilbert and Sullivan .
Esther's taste in literature was eclectic; her library included both
classics and contemporary works by such authors as
Esther commented that "Crichton never got it right." I asked her what she meant, and she replied that if an extraterrestrial life form were caught in an outer space probe and brought back to Earth, whatever would counteract it would with high probability be caught along with it in the same probe, because living things are always surrounded in their environment by those things that counteract it. "They should simply have looked in the same net," she said. "They would have found what they needed to control the alien life form."
Lederberg also loved the works of
BOTANY AND BOTANICAL GARDENS
Lederberg maintained a lifelong love of botany and botanical gardens
. She encouraged the planting of indigenous plants such as poppies and
lupins around the
Esther Miriam Zimmer Lederberg died November 11, 2006, from pneumonia and congestive heart failure, at the age of 83.
For a list of all known papers authored or co-authored by Esther M. Zimmer Lederberg, see http://www.scientificlegacies.org/esther-lederberg.html.
* ^ Ware, Doreen. "Pioneering Women in STEM". National Science Foundation. Retrieved 10 March 2016. * ^ A B "Stanford Magazine - Article". alumni.stanford.edu. Retrieved 2016-09-21. * ^ A B "Esther Lederberg, Pioneer of Bacterial Genetics". Small Things Considered. Retrieved 2016-09-21. * ^ A B C D "Miriam Esther Lederberg". What is Biotechnology?. Retrieved 19 March 2017. * ^ Simon, Matthew. "Agreement: Use of the Esther M. Zimmer Lederberg Memorial Website". www.estherlederberg.com. Retrieved 2016-09-21. * ^ A B C D E F G Alic, Margaret (1999). "Esther Miriam (Zimmer) Lederberg 1922-". In Proffitt, Pamela. Notable Women Scientists. Farmington Hill, Michigan: Gale Group. pp. 320–322. ISBN 0-7876-3900-1 . * ^ Hollaender, A., Sansome E.R., Zimmer, E., and Demerec, M. (April 1945) "Quantitative irradiation experiments with Neurospora crassa. II. Ultraviolet irradiation", American Journal of Botany 32(4):226-235 * ^ A B Maugh II, Thomas H. (30 November 2006). "Esther Lederberg, 83; helped unlock mysteries of bacteria and viruses". Los Angeles Times. Retrieved 24 March 2017. * ^ "Scientific Legacies: Esther Miriam Zimmer Lederberg (1922-2006)". Scientific Legacies. Retrieved 24 March 2017. * ^ A B C Gottesman ME, Weisberg RA (2004). "Little lambda, who made thee?" . Microbiology