| Jacques Monod | |
|---|---|
| Born | February 9, 1910 Paris, France |
| Died | May 31, 1976 (aged 66) Paris, France |
| Nationality | French |
| Fields | Biology |
| Known for | Lac operon, Allosteric regulation |
| Notable awards | Nobel Prize in Physiology or Medicine (1965) |
Jacques Lucien Monod (February 9, 1910 – May 31, 1976) was a French biologist who was awarded a Nobel Prize in Physiology or Medicine in 1965, sharing it with François Jacob and Andre Lwoff "for their discoveries concerning genetic control of enzyme and virus synthesis".[1] He and François Jacob showed that the living cell controls its manufacture of proteins through a feedback mechanism analogous to a thermostat.[2] Born in Paris, he was also awarded several other honours and distinctions, among them the Légion d'honneur. Monod (along with François Jacob) is famous for his work on the Lac operon. Study of the control of expression of genes in the Lac operon provided the first example of a transcriptional regulation system. He also suggested the existence of mRNA molecules that link the information encoded in DNA and proteins. Monod is widely regarded as one of the founders of molecular biology.[3][4]
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Monod was born in Paris to an American mother from Milwaukee, Charlotte (Sharlie) MacGregor Todd, and a French Huguenot father, Lucien Monod who was a painter and inspired him artistically and intellectually.[5][6] He attended the lycée at Cannes until he was 18.[5] In October 1928 he started his studies in biology at the Sorbonne.[5]
In his studies he discovered that the course work was decades behind the current biological science. He learned from other students a little older than himself, rather than from the faculty. "To George Teissier he owes a preference for quantitative descriptions; André Lwoff initiated him into the potentials of microbiology; to Boris Ephrussi he owes the discovery of physiological genetics, and to Louis Rapkine the concept that only chemical and molecular descriptions could provide a complete interpretation of the function of living organisms."[6]
Monod also made important contributions to the field of enzymology with his proposed theory of allostery in 1965 with Jeffries Wyman (1901-1995) and Jean-Pierre Changeux.[7] His doctoral work explored the growth of bacteria on mixtures of sugars and documented the sequential utilization of two or more sugars. He coined the term diauxie to denote the frequent observations of two distinct growth phases of bacteria grown on two sugars. He theorized on the growth of bacterial cultures and promoted the chemostat theory as a powerful continuous culture system to investigate bacterial physiology (1949, Ann. Rev. Microbiol., 3:371-394; 1950, Ann. Inst. Pasteur., 79:390-410).
The experimental system used by Jacob and Monod was a common bacterium, E. coli, but the basic regulatory concept (described in the Lac operon article) that was discovered by Jacob and Monod is fundamental to cellular regulation for all organisms. The key idea is that E. coli does not bother to waste energy making such enzymes if there is no need to metabolize lactose, such as when other sugars like glucose are available. The type of regulation is called negative gene regulation, as the operon is inactivated by a protein complex that is removed in the presence of lactose (regulatory induction).
He was also a proponent of the view that life on earth arose by freak chemical accident and was unlikely to be duplicated even in the vast universe. "Man at last knows he is alone in the unfeeling immensity of the universe, out of which he has emerged only by chance," he wrote in 1971. He used this bleak assessment as a springboard to argue for atheism and the absurdity and pointlessness of existence. Monod believed we are merely chemical extras in a majestic but impersonal cosmic drama—an irrelevant, unintended sideshow.
Monod was not only a biologist but also a fine musician and esteemed writer on the philosophy of science. He was a political activist and chief of staff of operations for the Forces Françaises de l'Interieur during World War II. In preparation for the Allied landings, he arranged parachute drops of weapons, railroad bombings, and mail interceptions.
Jacques Monod died of leukemia in 1976 and was buried in the Cimetière du Grand Jas in Cannes on the French Riviera.