A girl from Prague
Gerty Theresa Radnitz was born on August 15, 1896, in Prague, then part of the Austro-Hungarian Empire, into an upper-middle-class Jewish family. She was the eldest of three daughters of Otto Radnitz, a chemist who managed sugar refineries after inventing a successful method of refining sugar, and Martha Neustadt, a cultured woman and a friend of Franz Kafka.
Girls of her class were expected to be educated at home and in finishing schools, not to become scientists. Gerty was tutored privately and then attended a lyceum for girls. At sixteen, encouraged by her maternal uncle, a professor of paediatrics, she decided to become a doctor. She discovered that she lacked the Latin, physics, chemistry and mathematics needed for university entrance and made them up in an intense period of study, passing the entrance examination in 1914. That year she entered the medical school of the German University of Prague, a rare achievement for a woman at the time.
Carl
In her first year of medical school she met a fellow student, Carl Cori, who was drawn to her charm, humour and love of the outdoors and mountain climbing. They became inseparable, and while still students they published their first joint paper, on an immunological study of human blood serum. It was the start of a scientific partnership that lasted the rest of her life.
Both graduated in 1920 and married that year. Carl’s family opposed the match, convinced that her Jewish background would damage his career, and Gerty converted to Catholicism before the wedding. According to the Jewish Women’s Archive, the conversion did not quiet their fears. The young couple moved to Vienna, where Gerty worked at the Karolinen Children’s Hospital, studying temperature regulation and blood disorders. Postwar Austria was hungry, and she developed a serious eye condition from malnutrition.
Leaving Europe
The Coris’ decision to leave Europe was driven by hardship and, above all, by rising antisemitism, which made it nearly impossible for Gerty to find an academic post. In 1922 Carl accepted a position as biochemist at the State Institute for the Study of Malignant Disease in Buffalo, New York, and Gerty followed six months later as an assistant pathologist. They became American citizens in 1928 and never regretted the move.
In Buffalo they faced a different obstacle. The institute’s director threatened to dismiss Gerty unless she stopped collaborating with her husband. She carried on, and the two published about fifty papers there, many of them jointly. Gerty also published eleven as sole author.
In Buffalo the Coris began by studying the fate of sugar in the animal body and the effects of insulin and adrenaline on it. They also showed that tumours in living animals break down sugar in a distinctive way, an early contribution to the study of cancer metabolism. Their success rested on painstaking chemistry: they developed precise methods for measuring tiny amounts of sugars, lactic acid and phosphates, a hallmark of all their later work.
The Cori cycle
The question the Coris set out to answer was simple to ask and hard to solve: what controls the level of sugar in the blood? Through careful balance experiments on rats, and by developing precise methods for measuring glucose, glycogen, lactic acid and phosphates, they traced the journey of sugar around the body. When muscles work, they break down their store of glycogen, a starch-like chain of glucose, and release lactic acid into the blood. The liver takes up that lactic acid and turns it back into glucose, which the blood carries back to the muscles to be stored again.
In 1929 they proposed this loop, now called the Cori cycle, and showed how the hormones insulin and adrenaline shift sugar between muscle and liver. It is still taught to every medical and biology student, and it helps explain what happens to the body during exercise, fasting and illness, and why lactic acid can build up in the blood of very sick patients.
St. Louis and the Nobel Prize
In 1931 several universities offered Carl a post but refused to hire Gerty; one interviewer told her it was considered un-American for a married couple to work together. Carl turned down positions that would have separated them. Washington University in St. Louis hired both, Carl as chairman of pharmacology and Gerty as a research associate at about a tenth of his salary. She waited thirteen years to reach the same rank as her husband.
In 1936, the year their only child, Tom, was born, the Coris discovered a new compound in muscle, glucose-1-phosphate, now called the Cori ester. They identified phosphorylase, the enzyme that makes it from glycogen, and used it to build glycogen in a test tube, the first time a large biological molecule had been made outside a living cell. In 1947, months after Gerty became a full professor, she and Carl shared the Nobel Prize in Physiology or Medicine with the Argentine physiologist Bernardo Houssay. She was the first woman to receive the prize in medicine, the third woman to win any Nobel Prize in science, and the first American woman to do so.
The Coris also found that phosphorylase exists in two forms that the cell converts back and forth to control how fast glycogen is broken down. It was an early glimpse of a control mechanism, the switching of proteins on and off by adding or removing phosphate, now known to regulate a vast number of processes in the body and to be the target of many modern cancer drugs. They studied too how hormones of the pituitary gland affect the use of sugar and how insulin counteracts them, work that fed directly into the understanding of diabetes.
The first enzyme disease
Around the time of the Nobel Prize, Gerty learned she had myelosclerosis, an incurable disease of the bone marrow. She kept working for ten more years, and some of her most important research came in that last decade. She discovered the branching and debranching enzymes that build and dismantle the branch points of glycogen, and she turned that knowledge to sick children.
Some children were born with livers and muscles swollen with glycogen they could not use. In 1952 Gerty and her colleagues showed that in one form of this glycogen storage disease the liver lacks a single enzyme, glucose-6-phosphatase, and she went on to classify several forms, each caused by a different enzyme defect. It was the first proof that the lack of one enzyme could cause a human disease. Her work made accurate diagnosis possible and laid the groundwork for understanding the hundreds of inherited metabolic disorders now identified, many of them screened for at birth.
Her student Joseph Larner recalled her running down the hall shouting “It’s free glucose, it’s free glucose!” over one experimental result, and said she needed only one exciting finding to jump into a problem with unbounded energy. Her final paper, a review of glycogen storage disease, was published in 1957, the year she died.
Jewish heritage and the cost of prejudice
Gerty Cori’s life was shaped twice by prejudice: as a Jew in central Europe and as a woman in science. Her conversion to Catholicism was made, according to her biographer Sharon McGrayne, to ease the objections of Carl’s family, and antisemitism was the main reason the couple left Europe. In America she faced years of rules against married couples working together and was paid a fraction of what her husband earned for equal work.
She did not make speeches about either injustice. In the radio series This I Believe she named honesty, which she said stood mostly for intellectual integrity, together with courage and kindness, as the virtues she admired, adding that kindness mattered more to her with the years. She is honoured by the Jewish Women’s Archive and counted among Jewish Nobel laureates.
Teacher of laureates
The Cori laboratory became a magnet for scientists from around the world. Six researchers trained there went on to win Nobel Prizes, a record surpassed only by the laboratory of the British physicist J. J. Thomson. Colleagues remembered Gerty as vivacious and quick, with a passionate love of science.
President Harry Truman appointed her to the board of the National Science Foundation, and she served until her death. She was elected to the National Academy of Sciences, the American Academy of Arts and Sciences and the American Philosophical Society.
Last years and legacy
As her illness advanced, a cot was placed in her laboratory so she could rest, and Carl monitored her blood counts and carried her when she could not stand. She stayed active in research almost to the end and died at home in St. Louis on October 26, 1957, aged 61.
Craters on the Moon and Venus bear her name, and in 2008 the U.S. Postal Service honoured her with a stamp noting that her discoveries contributed to the understanding and treatment of diabetes and other metabolic diseases. Her shared laboratory at Washington University was designated a National Historic Chemical Landmark in 2004. More than that, every doctor who explains how the body fuels its muscles, and every child diagnosed with an inherited enzyme disorder, benefits from the work of a woman who had to fight for the right to do it.
Sources & further reading
Gerty Theresa Cori, Jewish Women’s Archive Encyclopedia · Gerty Cori, Biographical, NobelPrize.org · Meet the Nobel-winning biochemist who uncovered how the body stores and consumes sugars, ASBMB Today · Gerty Theresa Radnitz Cori, Jewish Virtual Library · Gerty Cori, Wikipedia · Researched from the sources above and checked against them. Spotted an error? Tell us.
A life of tikkun olam. This is part of tikkun olam, the Jewish idea of repairing the world, and every one of us can add to it.