François Jacob

from Wikipedia, the free encyclopedia
François Jacob

François Jacob (born June 17, 1920 in Nancy , France , † April 19, 2013 in Paris ) was a French physician, geneticist and molecular biologist who developed the operon model with Jacques Monod and coined the term operon . This model, also called the Jacob-Monod model, describes the structure of prokaryotic genes and explains how their activity is regulated ( gene regulation ). In 1965 Jacob received the Nobel Prize for Medicine together with Monod and André Lwoff .

Biography and life's work

François Jacob was born as the only son of Simon Jacob and Thérèse Franck on June 17, 1920 in Nancy. After completing school at the Lycée Carnot in Paris, he began studying at the Paris Faculty of Medicine at the Sorbonne with the intention of becoming a surgeon . During the Second World War, however, he had to interrupt his studies. During his sophomore year in June 1940, he left France to join the Free French Forces (France libre) in London as a resistance fighter. As a medical officer, he took part in military operations in Fezzan , Libya and Tunisia , where he was wounded. He was then transferred to the Second Armored Division , where he was seriously wounded again in Normandy in August 1944 . He cured his injuries in the hospital for seven months. He was then awarded the Croix de la Liberation (Cross of Liberation), the highest military war award. After the war, Jacob completed his medical studies in Paris in 1947 with the achievement of the doctorate.

In the same year he married the pianist Lise Bloch. The marriage had four children: Pierre (* 1949), who became a philosopher, Laurent and Odile (* 1952) and Henri (* 1954).

Because of his severe war injuries, Jacob could not work as a surgeon. He initially worked in various other areas until he turned to biology in 1950 as a student of André Lwoff at the Pasteur Institute . In 1951 he completed his natural science studies and in 1954 obtained his doctorate at the Sorbonne with a thesis on lysogenic bacteria and the provirus concept ("Lysogenic bacteria and the provirus concept"). In 1956 he was appointed laboratory director. From 1960 he was head of the recently established Department of Cellular Genetics at the Pasteur Institute. In 1964 he received a professorship at the Collège de France , where a chair in cell genetics was created for him.

François Jacob was particularly concerned with genetic mechanisms in bacteria and bacteriophages as well as the biochemical consequences of point mutations . Initially he investigated the properties of lysogenic bacteria and demonstrated their resistance to prophages , which he explained with the existence of mechanisms that inhibit the activity of prophage genes .

1954 began a long and fruitful collaboration with Elie Wollman, in which connections and relationships between the genetic material of the bacterium and its prophage were clarified. These studies led to an understanding of bacterial conjugation and made it possible to analyze the genetic apparatus of a bacterial cell. In their collaboration they developed many new concepts: They explained the gene exchange between donor and recipient cells during conjugation, demonstrated the circular structure of the bacterial chromosome and discovered episomes . They summarized the results of their research in the work Sexuality and Bacterial Genetics.

Remarkable similarities between the control of lysogeny and the induced synthesis of β-galactosidase by lactose in bacteria inspired François Jacob, together with Jacques Monod, in 1958 to elucidate the genetic mechanisms that cause gene exchange between bacteria and control the induced synthesis of proteins in bacteria. In this context, Jacob and Monod developed a model ( operon model) for the interaction of regulatory genes , operators , promoters , structural genes and allosteric proteins , the repressors , in the synthesis of messenger RNA ( transcription ).

In 1963, Jacob and Sydney Brenner advanced the "Replicon" hypothesis to explain certain aspects of bacterial cell division. Since then, Jacob has devoted himself to research into the genetic mechanisms that control cell division. In 1970 he began to study these mechanisms in mammalian cells from cell cultures . In the same year, the cell biologist published the book La logique du vivant, une histoire de l'hérédité (The logic of the living, a history of heredity) , in which he traced important stages in the study of living things beginning in the 16th century transferred to molecular biology .

Awards

In addition to the Nobel Prize in Physiology or Medicine in 1965, François Jacob was awarded numerous science prizes in France. The Charles Léopold Mayer Prize from the Académie des sciences (1962) deserves special mention . He has been a foreign member of the Danish Royal Academy of Arts and Sciences since 1962 , the American Academy of Arts and Sciences (1964), the National Academy of Sciences of the United States (1969), the American Philosophical Society (1969) and the Royal Society (1973). He received honorary doctorates from several universities. In 1958 he was invited to give the Harvey Lecture in New York and in 1964 the Dunham Lecture at Harvard University. In 1977 he received the Leeuwenhoek Medal from the Royal Society.

In 1996 Jacob was accepted as a member of the Académie française .

In honor of the two discoverers, the operon model for gene regulation is also referred to as the Jacob-Monod model.

François Jacob is the holder of the Ordre de la Liberation and was Chancellor of the Order from 2007 to 2011.

literature

Web links

Commons : François Jacob  - Collection of images, videos and audio files

Individual evidence

  1. ^ Décès de François Jacob, prix nobel de médecine
personal data
SURNAME Jacob, François
BRIEF DESCRIPTION French medic, physiologist and geneticist
DATE OF BIRTH June 17, 1920
PLACE OF BIRTH Nancy , France
DATE OF DEATH April 19, 2013
Place of death Paris