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Powder puffs and plasmids - Esther Lederberg

Powder puffs and plasmids - Esther Lederberg

Esther Lederberg.  Image via Wikimedia Commons , Esther M Zimmer Lederberg Trust

Esther Lederberg. Image via Wikimedia Commons, Esther M Zimmer Lederberg Trust

New York, 1922. A time of speakeasies, prohibition and squeezed pocketbooks. It’s the week after Hanukkah in the Bronx, and Pauline and David Zimmer have just welcomed baby Esther into the world.

Money’s tight, but young Esther is excelling at school, and heads to Hunter College, part of the public New York City University. But instead of studying languages or literature, as her teachers hoped, she switched to biochemistry. Not a suitable subject for a young Jewish girl, and certainly nothing one could make a career from. Science, schmience…

An academic superstar, Esther graduated cum laude at the age of just 20 and went to work as a research assistant with Alexander Hollaender at what later became Cold Spring Harbor Laboratory in New York, where she published her first paper on the genetics of the red bread mould, Neurospora. A couple of years later, in 1942, she won a fellowship to Stanford University in California, working with George Beadle – remember that name – and embarked on her research career.

Coming from a poor family who weren’t able to provide financial support, Esther supplemented her meagre income by working as a teaching assistant and managed to blag free accommodation by washing her landlady’s clothes and cleaning the house. She even allegedly occasionally resorted to eating the frog’s legs left over from dissection classes!

1946 was a big year for Esther Zimmer: not only did she get her master’s degree from Stanford, she also married Joshua Lederberg.  And that’s when things started to go downhill.

At this point, Lederberg – three years her junior – had already secured an assistant professorship at the University of Wisconsin, even though he hadn’t yet finished his doctorate, so his new wife quit California to join him there and work on her own PhD, focusing on the genetics of bacteria.

It’s from this work she made her most important discovery: Lambda phage, an example of new type of virus called a bacteriophage, which hides inside the DNA of bacteria, multiplying and bursting out of the bugs in response to a trigger such as ultraviolet light. Esther delved into the world of Lambda, alongside Joshua and the rest of his team, investigating how genetic material was transferred between bacteria, finding a key factor required for bacteria to have sex – the F or fertility factor – and more.

Along the way, she developed an important technique known as replica plating, still used in microbiology labs all over the world today to make a perfect copy of all the bacterial colonies growing on a plate of nutrient jelly. Esther realised that if she pressed a pad covered in velvet cloth onto the plate of bacteria, then pressed it onto a clean plate, the fibres of the fabric would act as tiny needles, picking up just enough bacteria to start an identical colony. It’s a simple idea, but nobody had thought of it before, and it revolutionised the field.

As a delightfully feminine detail, she first tested the idea using the powder puff from her makeup compact, and then spent a lot of time finding the right brand of fabric, and how to wash and prepare it for the best results – even down to the best detergent to use.

Esther and Joshua Lederberg. OMG that side-eye…  Image via Wikimedia Commons,  Esther M. Zimmer Lederberg Memorial Web Site

Esther and Joshua Lederberg. OMG that side-eye… Image via Wikimedia Commons, Esther M. Zimmer Lederberg Memorial Web Site

1958 was another big year for the Lederbergs – Joshua won a half share of the Nobel prize for his work investigating how genetic material was transferred between bacteria, and many aspects of how genes are switched on and off.

But who got the other half? It certainly wasn’t his wife, whose work with Lambda phage and bacteria had been so crucial for his success. No. It went to Edward Tatum and George Beadle, Esther’s original supervisor at Stanford. She wasn’t even mentioned in the citation.

The Lederbergs headed back to Stanford, where Joshua had been invited to establish and chair a new Department of Genetics Despite being roughly the same age, and his intellectual equal, the contrast between their careers couldn’t be more striking – Joshua racks up position after position, professorships, department heads, election to the National Academy of Sciences.

Yet while her husband’s academic star was ascendant, helped by her work, Esther struggled to get a job at Stanford, going with two other women to the Dean to demand he appoint at least one woman onto the faculty. She eventually landed a position, for which she was overqualified, and was only offered the job because it was unpaid.

It may not come as a surprise to learn that the Lederbergs marriage ended in 1966, and Esther promptly set up a group for divorced women at Stanford, which sounds like it was a blast.

Left to her own devices, Esther took over Stanford’s Plasmid Reference Centre, a vital collection of tiny circles of DNA that can be put into bacteria for all sorts of purposes. She even kept on volunteering there after her retirement in 1985 – the year she was finally recognised by Stanford with the honour of Professor Emerita.

Science wasn’t her only passion, and Esther was a big fan of medieval, renaissance and baroque music, establishing the Mid-Peninsula Recorder Orchestra in Menlo Park, which is still puffing away today. It’s also how she met her second husband, Matthew Simon, who she married in 1993, when she was 70.   

Esther died in 2006, at the age of 83. Frustratingly, her obituary in the New York Times manages to mention her ex-husband at least four times, including the fact that he had been the president of the Rockefeller University, and had just been awarded the Presidential Medal of Freedom by George Bush. Even in death, she was overshadowed by the man she had divorced forty years earlier.

L’chaim, Esther! Let’s reclaim your story.

References and further reading

E&J Esther M. Zimmer Lederberg Memorial Web Site via Wikimedia Commons

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