Jacques Monod
Encyclopedia
Jacques Lucien Monod 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". He and François Jacob showed that the living cell controls its manufacture of proteins through a feedback mechanism analogous to a thermostat. 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 gene
s 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.
mother from Milwaukee, Charlotte (Sharlie) MacGregor Todd, and a French Huguenot
father, Lucien Monod who was a painter and inspired him artistically and intellectually. He attended the lycée at Cannes
until he was 18. In October 1928 he started his studies in biology at the Sorbonne
.
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."
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
. 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 in 1976 and was buried in the Cimetière du Grand Jas
in Cannes
on the French Riviera
.
French people
The French are a nation that share a common French culture and speak the French language as a mother tongue. Historically, the French population are descended from peoples of Celtic, Latin and Germanic origin, and are today a mixture of several ethnic groups...
biologist
Biology
Biology is a natural science concerned with the study of life and living organisms, including their structure, function, growth, origin, evolution, distribution, and taxonomy. Biology is a vast subject containing many subdivisions, topics, and disciplines...
who was awarded a Nobel Prize in Physiology or Medicine
Nobel Prize in Physiology or Medicine
The Nobel Prize in Physiology or Medicine administered by the Nobel Foundation, is awarded once a year for outstanding discoveries in the field of life science and medicine. It is one of five Nobel Prizes established in 1895 by Swedish chemist Alfred Nobel, the inventor of dynamite, in his will...
in 1965, sharing it with François Jacob
François Jacob
François Jacob is a French biologist who, together with Jacques Monod, originated the idea that control of enzyme levels in all cells occurs through feedback on transcription. He shared the 1965 Nobel Prize in Medicine with Jacques Monod and André Lwoff.-Childhood and education:François Jacob is...
and Andre Lwoff "for their discoveries concerning genetic control of enzyme and virus synthesis". He and François Jacob showed that the living cell controls its manufacture of proteins through a feedback mechanism analogous to a thermostat. Born in Paris
Paris
Paris is the capital and largest city in France, situated on the river Seine, in northern France, at the heart of the Île-de-France region...
, he was also awarded several other honours and distinctions, among them the Légion d'honneur
Légion d'honneur
The Legion of Honour, or in full the National Order of the Legion of Honour is a French order established by Napoleon Bonaparte, First Consul of the Consulat which succeeded to the First Republic, on 19 May 1802...
. Monod (along with François Jacob) is famous for his work on the Lac operon
Lac operon
The lac operon is an operon required for the transport and metabolism of lactose in Escherichia coli and some other enteric bacteria. It consists of three adjacent structural genes, lacZ, lacY and lacA. The lac operon is regulated by several factors including the availability of glucose and of...
. Study of the control of expression of gene
Gene
A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...
s in the Lac operon provided the first example of a transcriptional
Transcription (genetics)
Transcription is the process of creating a complementary RNA copy of a sequence of DNA. Both RNA and DNA are nucleic acids, which use base pairs of nucleotides as a complementary language that can be converted back and forth from DNA to RNA by the action of the correct enzymes...
regulation system. He also suggested the existence of mRNA molecules that link the information encoded in DNA
DNA
Deoxyribonucleic acid is a nucleic acid that contains the genetic instructions used in the development and functioning of all known living organisms . The DNA segments that carry this genetic information are called genes, but other DNA sequences have structural purposes, or are involved in...
and proteins. Monod is widely regarded as one of the founders of molecular biology.
Personal life
Monod was born in Paris to an AmericanUnited States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
mother from Milwaukee, Charlotte (Sharlie) MacGregor Todd, and a French Huguenot
Huguenot
The Huguenots were members of the Protestant Reformed Church of France during the 16th and 17th centuries. Since the 17th century, people who formerly would have been called Huguenots have instead simply been called French Protestants, a title suggested by their German co-religionists, the...
father, Lucien Monod who was a painter and inspired him artistically and intellectually. He attended the lycée at Cannes
Cannes
Cannes is one of the best-known cities of the French Riviera, a busy tourist destination and host of the annual Cannes Film Festival. It is a Commune of France in the Alpes-Maritimes department....
until he was 18. In October 1928 he started his studies in biology at the Sorbonne
University of Paris
The University of Paris was a university located in Paris, France and one of the earliest to be established in Europe. It was founded in the mid 12th century, and officially recognized as a university probably between 1160 and 1250...
.
Professional life
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 EphrussiBoris Ephrussi
Boris Ephrussi , Professor of Genetics at the University of Paris, was a Russo-French geneticist from the Ephrussi family.His father, Samuil Osipovich Ephrussi, was a chemical engineer; his grandfather, Joseph Ephrusi , was the founder of a banking dynasty in Kishinev. He published two papers in...
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."
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
Jean-Pierre Changeux
Jean-Pierre Changeux is a French neuroscientist known for his research in several fields of biology, from the structure and function of proteins , to the early development of the nervous system up to cognitive functions...
. 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
Diauxie
Diauxie is a French word coined by Jacques Monod to mean two growth phases. The word is used in English in cell biology to describe the growth phases of a microorganism in batch culture as it metabolizes a mixture of two sugars...
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
Lac operon
The lac operon is an operon required for the transport and metabolism of lactose in Escherichia coli and some other enteric bacteria. It consists of three adjacent structural genes, lacZ, lacY and lacA. The lac operon is regulated by several factors including the availability of glucose and of...
article) that was discovered by Jacob and Monod is fundamental to cellular
Cell (biology)
The cell is the basic structural and functional unit of all known living organisms. It is the smallest unit of life that is classified as a living thing, and is often called the building block of life. The Alberts text discusses how the "cellular building blocks" move to shape developing embryos....
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
Lactose
Lactose is a disaccharide sugar that is found most notably in milk and is formed from galactose and glucose. Lactose makes up around 2~8% of milk , although the amount varies among species and individuals. It is extracted from sweet or sour whey. The name comes from or , the Latin word for milk,...
, such as when other sugars like glucose
Glucose
Glucose is a simple sugar and an important carbohydrate in biology. Cells use it as the primary source of energy and a metabolic intermediate...
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
Philosophy of science
The philosophy of science is concerned with the assumptions, foundations, methods and implications of science. It is also concerned with the use and merit of science and sometimes overlaps metaphysics and epistemology by exploring whether scientific results are actually a study of truth...
. He was a political activist and chief of staff of operations for the Forces Françaises de l'Interieur during World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
. In preparation for the Allied landings, he arranged parachute drops of weapons, railroad bombings, and mail interceptions.
Jacques Monod died in 1976 and was buried in the Cimetière du Grand Jas
Cimetière du Grand Jas
The Cimetière du Grand Jas is located at 205 avenue de Grasse in Cannes on the French Riviera. The nine hectare terraced cemetery began operations in 1866 and is known for its landscaped architecture with rich floral decorations and statuary.Its "English square" or Cimetière Anglais, is the final...
in Cannes
Cannes
Cannes is one of the best-known cities of the French Riviera, a busy tourist destination and host of the annual Cannes Film Festival. It is a Commune of France in the Alpes-Maritimes department....
on the French Riviera
French Riviera
The Côte d'Azur, pronounced , often known in English as the French Riviera , is the Mediterranean coastline of the southeast corner of France, also including the sovereign state of Monaco...
.
Quotations
- "The first scientific postulate is the objectivity of nature: nature does not have any intention or goal."
- "Anything found to be true of E. coli must also be true of elephants."
External links
- Biography of Jacques Monod at Nobel e-Museum
- Video interview with Jacques Monod Vega Science Trust
- From enzymatic adaptation to allosteric transitions Nobel Lecture, December 11, 1965