by Gidon Schwartz, Education & Outreach Executive

Microbiology is the study of microorganisms, tiny life forms that quietly shape almost every part of our world. It is central to medicine, vaccine development, infection control, agriculture, food production, and even our own digestive health. During the Covid-19 pandemic, microbiologists worked urgently to understand the virus’s structure so that vaccines and public health measures could be developed. Yet microbes are also part of ordinary life, helping to produce cheese, bread and fermented foods, supporting soil health, and sustaining the delicate bacterial balance within our gut. Much of what we know about bacteria, and the viruses that infect them, stems from the quiet curiosity and determination of scientists like Esther Lederberg, a pioneer whose work transformed genetics and microbiology even as the world often overlooked her.

Esther Lederberg (née Zimmer) was born in 1922 in New York to Pauline Geller Zimmer and David Zimmer, a Romanian immigrant who ran a print shop. Her early exposure to printing presses would later inspire one of her most important scientific innovations. While others saw only machinery, Esther saw a method. She used that childhood familiarity to develop replica plating, a clever technique that allowed her to “print” bacterial colonies from one plate to another using sterile fabric. It was a simple, elegant solution born from curiosity, and it enabled her to show that genetic traits do not change in response to the environment, overturning assumptions rooted in Lamarckian thinking that had endured since 1809. This technique is so fundamental, it is routinely used to this day.

Esther’s determination to pursue science emerged early. She graduated high school at fifteen and enrolled in biochemistry at Hunter College despite teachers insisting that science was not a career for women. Undeterred, she excelled, later earning a bachelor’s degree in genetics while working as a research assistant on Neurospora crassa, a mould that infects plants. She followed her interests to Stanford University, completing a master’s degree focused on the same organism. Each step in her education was guided not by encouragement or institutional support, but by her own drive to understand how life works at its smallest scales.

In 1946, Esther married Joshua Lederberg, a young scientist at Yale University. They later moved to the University of Wisconsin, where Joshua became a professor and Esther pursued her PhD. Her research explored how Escherichia coli bacteria mutate and adapt, leading to discoveries that reshaped modern genetics. She identified the lambda phage, a virus that infects bacterial cells, and discovered F plasmids, which enable bacteria to transfer genetic material between cells. These findings revolutionised the study of bacterial evolution, adaptation, and gene exchange – the very discovery that allows genetic modification and gene therapy which are at the forefront of modern research. Each breakthrough began the same way: with a subtle question, followed by careful observation and persistent investigation. Her curiosity drove the science forward long before anyone recognised how significant her contributions would become.

Despite her achievements, the world often refused to give Esther proper credit. In 1956, she shared the Pasteur Award with her husband, but the recognition she received never matched the scale of her contributions. When Joshua won the Eli Lilly Award in 1953, he told reporters that Esther should have been included. In 1958, he won the Nobel Prize in Physiology or Medicine alongside George Beadle and Edward Tatum. Esther’s discoveries were foundational to the research that led to the prize, yet she was not named and became known simply as the Nobel laureate’s wife. Though Joshua acknowledged her in his Nobel lecture, their return to Stanford brought further inequity. He was appointed head of the genetics department, while she was offered only a research associate position in another department. Years later, she finally received a faculty role, but without tenure, a rank that did not reflect her expertise or impact. She accepted the position and continued her scientific work until her retirement in 1985, driven by the same quiet determination that had guided her since childhood.

Beyond science, Esther loved early music and played medieval, Renaissance and baroque pieces on original instruments. She founded a recorder orchestra in 1962 and devoted time to reading Dickens and Austen, attending society meetings to study their works.

Esther Lederberg’s story is a powerful reminder that scientific revolutions do not always come from loud voices or celebrated names. Sometimes they come from a scientist who simply keeps asking questions, keeps looking closely and keeps working, even when recognition does not follow. Her quiet curiosity and unwavering determination changed the course of genetics and microbiology, shaping the field in ways that continue to guide research today. Her legacy shows that science can be transformed by those who persist in the pursuit of understanding, even when the world refuses to give them the credit they deserve.

by Gidon Schwartz, Education & Outreach Executive

David de Pomis was living the ideals of Torah and worldly wisdom centuries before anyone gave the concept a name. Long before Yeshiva University articulated the idea of Torah u’Madda, the integration of Torah study with academic pursuits, this young Jewish scholar of 16th-century Italy was already weaving sacred learning and secular knowledge into a single, purposeful life. He was a physician, rabbi, linguist, philosopher, and without intending to be, a pioneer of a new Jewish intellectual identity and the ideals that today, underpin modern orthodoxy. Yet David’s story was far from the smooth ascent one might expect from a man of noble birth. His life was marked not by inherited privilege, but by loss, perseverance, and a determined rise through the power of learning.

David entered the world in 1525 bearing a name steeped in antiquity. The de Pomis family, known in ancient Judea as Min haTapuchim (“the Apple clan”), traced their lineage back to the Land of Israel and even claimed descent from King David. They were said to be among the 4 noble families exiled to Rome by Titus after the destruction of the Second Temple, a living bridge between antiquity and Renaissance Europe. But aristocratic origins did not protect the family from catastrophe. When David was only two, the brutal 1527 Sack of Rome shattered everything they had. Isaac de Pomis, David’s father, sent their possessions to nearby cities in a desperate attempt to save their wealth, but the convoy was ambushed and everything was stolen. Overnight, the ancient and distinguished de Pomis family was left destitute.

Still, Isaac held on tightly to what mattered most: his son’s education. In Camerino, where the family resettled, he taught David Torah and Talmud, laying the foundations of a rabbinic mind. After Isaac’s death, David’s uncle continued his education, adding medicine and philosophy. What began as aristocratic privilege now grew into something more meaningful—a fusion of traditions that allowed David to move fluidly between the worlds of Talmudic study and Renaissance science. In 1551 he earned his medical degree from the University of Perugia, poised for a respectable and stable future as both a rabbi and a physician.

But in Renaissance Italy, a Jewish doctor’s career could rise or fall with the mood of the pope. David’s first position, as rabbi and physician in Magliano Sabino, was abruptly ended by Pope Paul IV’s harsh anti-Jewish decrees. Jews were barred from treating Christians, their property was restricted, and David’s rabbinate was revoked. Once again, he was forced into instability, moving from town to town, unable to put down roots.

A brief reprieve arrived in 1565 when Pope Pius IV granted him a personal exemption to practice medicine on Christians—a rare recognition of his skill. But within days the pope died, and his successor, Pius V, withdrew the privilege. David fled to Venice, where he turned his energy to writing. In exile, his creativity flourished. He produced an Italian translation of Kohelet (Ecclesiastes), a treatise on the bubonic plague, and a remarkable trilingual Talmudic dictionary spanning Hebrew, Aramaic, Latin, and Italian. At a time when Jewish scholarship and European academia were largely separate worlds, David stood comfortably in both. His work made him a kind of Renaissance Jew before such a figure was widely imaginable. In time, his relationship with the papacy even softened; he later dedicated a major work to Pope Sixtus V.

The culmination of David’s intellectual journey was his book Medico Hebræo, where he merged medicine, philosophy, and Jewish learning into a passionate defence of his people. He documented the injustices inflicted on Jews, refuted common accusations, and articulated a vision of medical ethics grounded in compassion and respect. It was the voice of a man who had risen from loss and displacement to become a spokesperson for dignity and reason.

Centuries later, the ideals embodied in David de Pomis’ life would be formalized under names like Torah u’Madda. But for David, the integration of sacred and worldly knowledge was not a slogan—it was a necessity, a survival strategy, and ultimately a calling. From aristocratic origins through poverty, from papal persecution to intellectual acclaim, he forged a path defined not by privilege but by perseverance. His life reminds us that greatness often begins with hardship, and that sometimes the most enduring contributions are made by those who must rebuild themselves through learning, one step at a time.