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Louis Pasteur: the story on HearLore | HearLore
Louis Pasteur
Louis Pasteur was born on the 27th of December 1822 in Dole, Jura, France, into a family of poor tanners, yet he would become the architect of modern microbiology. His early years were marked by struggles that seemed to preclude any future scientific greatness. He was dyslexic and dysgraphic, an average student who found more joy in fishing and sketching pastels of his parents and neighbors than in academic rigor. He failed his first examination in 1841 and only managed to pass his general science degree with a mediocre grade in chemistry. It was not until 1843, after retaking the entrance test for the École Normale Supérieure, that he achieved a high ranking and entered the prestigious institution. His early academic path was a series of near-misses and recoveries, including a brief return to a Parisian boarding school out of homesickness in 1838. Despite these hurdles, he developed a profound interest in crystallography and submitted two theses in 1847, one in chemistry and one in physics, which would lay the groundwork for his most famous discovery regarding molecular asymmetry. His marriage to Marie Laurent in 1849 brought personal tragedy as three of their five children died of typhoid, leaving only two to survive to adulthood. This personal loss likely fueled his later dedication to understanding and preventing infectious diseases.
The Crystal That Twisted Light
In 1848, Pasteur solved a problem that had baffled chemists for decades by noticing that crystals of tartrates had small faces that were mirror images of one another. He observed that in racemic mixtures of tartrates, half of the crystals were right-handed and half were left-handed, and when separated, one form rotated light to the right while the other rotated it to the left. This discovery demonstrated molecular chirality for the first time, proving that the asymmetric internal arrangement of molecules was responsible for twisting polarized light. His work on sodium ammonium tartrate initiated the field of optical isomerism, which had profound implications for structural chemistry and medicinal chemistry. Some historians consider this his most profound and original contribution to science, yet it was overshadowed by his later work on fermentation and disease. The problem was that tartaric acid derived by chemical synthesis had no such effect, even though its chemical reactions were identical and its elemental composition was the same. Pasteur determined that optical activity related to the shape of the crystals, and that an asymmetric internal arrangement of the molecules of the compound was responsible for twisting the light. This insight into the molecular basis for the asymmetry of certain crystals was a breakthrough that would eventually influence many areas of science, including the development of drugs that target specific molecular shapes.
Common questions
When was Louis Pasteur born and where did he grow up?
Louis Pasteur was born on the 27th of December 1822 in Dole, Jura, France. He grew up in a family of poor tanners and struggled academically as a child due to dyslexia and dysgraphia.
What discovery did Louis Pasteur make about molecular chirality in 1848?
Louis Pasteur discovered molecular chirality in 1848 by observing that crystals of tartrates had mirror-image faces that rotated polarized light in opposite directions. This finding proved that the asymmetric internal arrangement of molecules was responsible for optical activity.
How did Louis Pasteur develop the process of pasteurization in 1854?
Louis Pasteur developed pasteurization in 1854 while studying fermentation at the University of Lille. He demonstrated that heating liquids to between 60 and 100 degrees Celsius killed bacteria and moulds, a method patented in 1865 to prevent diseases in wine, beer, and milk.
What disease did Louis Pasteur study in silkworms between 1865 and 1869?
Louis Pasteur studied pébrine, a disease characterized by black spots and microscopic Cornalia corpuscles, in silkworm farms from 1865 to 1869. He developed a system to destroy eggs containing the disease and saved much of the silk industry in the Cévennes region.
When did Louis Pasteur administer the first rabies vaccine to Joseph Meister?
Louis Pasteur administered the first rabies vaccine to Joseph Meister on the 6th of July 1885. The 9-year-old boy received 13 inoculations over 11 days and survived, establishing the foundation for modern vaccine manufacturing.
When did Louis Pasteur die and where is he buried?
Louis Pasteur died on the 28th of September 1895 near Paris after suffering from a stroke and uremia in 1894. His remains were reinterred in a vault beneath the Pasteur Institute in Paris after a state funeral at the Cathedral of Notre Dame.
In 1854, Pasteur was named dean of the new faculty of sciences at the University of Lille, where he began his studies on fermentation after a local wine manufacturer sought his advice on souring beetroot alcohol. He demonstrated that fermentation was caused by living yeast, not by chemical decomposition as Justus von Liebig and Jöns Jacob Berzelius had proposed. When a different microorganism contaminated the wine, lactic acid was produced, making the wine sour. This research led to the invention of a process in which liquids such as milk were heated to a temperature between 60 and 100 degrees Celsius to kill most bacteria and moulds already present within them. The method became known as pasteurization and was soon applied to beer and milk. Pasteur patented the process in 1865 to fight the diseases of wine, and his work established that micro-organisms infecting animals and humans cause disease. He proposed preventing the entry of micro-organisms into the human body, leading Joseph Lister to develop antiseptic methods in surgery. His research also showed that the growth of micro-organisms was responsible for spoiling beverages, such as beer, wine and milk. In 1866, Pasteur published Études sur le Vin, about the diseases of wine, and he published Études sur la Bière in 1876, concerning the diseases of beer. His work on fermentation laid the foundation for the germ theory of diseases, which was a minor medical concept at the time.
The Silkworms That Died
In 1865, Pasteur was asked to study a new disease that was decimating silkworm farms from the south of France and Europe, the pébrine, characterized on a macroscopic scale by black spots and on a microscopic scale by the Cornalia corpuscles. He accepted and made five long stays in Alès, between the 7th of June 1865 and 1869, where he worked at the magnanerie of Pont Gisquet. Initially, Pasteur made mistakes, believing that the two diseases, pébrine and flacherie, were the same and even that most of the diseases of silkworms known up to that time were identical with each other and with pébrine. He began by denying the parasitic nature of pébrine, which several scholars considered well established. However, he eventually concluded that the corpuscles were the cause of pébrine and that the disease was hereditary. Pasteur developed a system to prevent pébrine: after the female moths laid their eggs, the moths were turned into a pulp. The pulp was examined with a microscope, and if corpuscles were observed, the eggs were destroyed. By this process, Pasteur curbed pébrine and saved much of the silk industry in the Cévennes. Despite his success against pébrine, French sericulture had not been saved from damage, as flacherie still exerted its ravages. In 1878, at the Congrès international séricicole, Pasteur admitted that if pébrine is overcome, flacherie still exerts its ravages. He attributed the persistence of flacherie to the fact that the farmers had not followed his advice. Despite Pasteur's success against pébrine, French sericulture had not been saved from damage, as flacherie still exerted its ravages.
The Rabies That Killed A Boy
On the 6th of July 1885, Pasteur administered the first rabies vaccine to a 9-year-old boy named Joseph Meister, who had been badly mauled by a rabid dog. This was done at some personal risk for Pasteur, since he was not a licensed physician and could have faced prosecution for treating the boy. After consulting with physicians, he decided to go ahead with the treatment. Over 11 days, Meister received 13 inoculations, each inoculation using viruses that had been weakened for a shorter period of time. Three months later he examined Meister and found that he was in good health. Pasteur was hailed as a hero and the legal matter was not pursued. Analysis of his laboratory notebooks shows that Pasteur had treated two people before his vaccination of Meister. One survived but may not actually have had rabies, and the other died of rabies. Pasteur began treatment of Jean-Baptiste Jupille on the 20th of October 1885, and the treatment was successful. Later in 1885, people, including four children from the United States, went to Pasteur's laboratory to be inoculated. In 1886, he treated 350 people, of which only one developed rabies. The treatment's success laid the foundations for the manufacture of many other vaccines. The first of the Pasteur Institutes was also built on the basis of this achievement. The rabies vaccine was initially created by Emile Roux, a French doctor and a colleague of Pasteur, who had produced a killed vaccine using this method. The vaccine had been tested in 50 dogs before its first human trial.
The Secret That Shook Science
In 1995, the centennial of the death of Louis Pasteur, a historian of science Gerald L. Geison published an analysis of Pasteur's private notebooks in his The Private Science of Louis Pasteur, and declared that Pasteur had given several misleading accounts and played deceptions in his most important discoveries. A French national hero at age 55, in 1878 Pasteur discreetly told his family to never reveal his laboratory notebooks to anyone. His family obeyed, and all his documents were held and inherited in secrecy. Being that Pasteur did not allow others in his laboratory to keep notebooks, this secrecy kept many aspects of his research unknown until relatively recently. Finally, in 1964 Pasteur's grandson and last surviving male descendant, Pasteur Vallery-Radot, donated the papers to the French national library. Yet the papers were restricted for historical studies until the death of Vallery-Radot in 1971. The documents were given a catalogue number only in 1985. In 1995, the centennial of the death of Louis Pasteur, a historian of science Gerald L. Geison published an analysis of Pasteur's private notebooks in his The Private Science of Louis Pasteur, and declared that Pasteur had given several misleading accounts and played deceptions in his most important discoveries. Max Perutz published a defense of Pasteur in The New York Review of Books. Based on further examinations of Pasteur's documents, French immunologist Patrice Debré concluded in his book Louis Pasteur in 1998 that, in spite of his genius, Pasteur had some faults. A book review states that Debré sometimes finds him unfair, combative, arrogant, unattractive in attitude, inflexible and even dogmatic. Pasteur's experiments are often cited as against medical ethics, especially on his vaccination of Meister. He did not have any experience in medical practice, and more importantly, lacked a medical license. This is often cited as a serious threat to his professional and personal reputation. His closest partner Emile Roux, who had medical qualifications, refused to participate in the clinical trial, likely because he considered it unjust. However, Pasteur executed vaccination of the boy under the close watch of practising physicians Jacques-Joseph Grancher, head of the Paris Children's Hospital's paediatric clinic, and Alfred Vulpian, a member of the Commission on Rabies. He was not allowed to hold the syringe, although the inoculations were entirely under his supervision. It was Grancher who was responsible for the injections, and he defended Pasteur before the French National Academy of Medicine in the issue. Pasteur has also been criticized for keeping secrecy of his procedure and not giving proper pre-clinical trials on animals. Pasteur stated that he kept his procedure secret in order to control its quality. He later disclosed his procedures to a small group of scientists. Pasteur wrote that he had successfully vaccinated 50 rabid dogs before using it on Meister. According to Geison, Pasteur's laboratory notebooks show that he had vaccinated only 11 dogs.
The Institute That Outlived Him
After developing the rabies vaccine, Pasteur proposed an institute for the vaccine. In 1887, fundraising for the Pasteur Institute began, with donations from many countries. The official statute was registered in 1887, stating that the institute's purposes were the treatment of rabies according to the method developed by M. Pasteur and the study of virulent and contagious diseases. The institute was inaugurated on the 14th of November 1888. He brought together scientists with various specialties. The first five departments were directed by two graduates of the École Normale Supérieure: Emile Duclaux and Charles Chamberland, as well as a biologist, Élie Metchnikoff, and two physicians, Jacques-Joseph Grancher and Emile Roux. One year after the inauguration of the institute, Roux set up the first course of microbiology ever taught in the world, then entitled Cours de Microbie Technique. Since 1891 the Pasteur Institute had been extended to different countries, and currently there are 32 institutes in 29 countries in various parts of the world. Pasteur was the director of the Pasteur Institute, established in 1887, until his death, and his body was interred in a vault beneath the institute. In 1868, Pasteur suffered a severe stroke that paralysed the left side of his body, but he recovered. A stroke or uremia in 1894 severely impaired his health. Failing to fully recover, he died on the 28th of September 1895, near Paris. He was given a state funeral and was buried in the Cathedral of Notre Dame, but his remains were reinterred in the Pasteur Institute in Paris, in a vault covered in depictions of his accomplishments in Byzantine mosaics. The French Academician Henri Mondor stated: Louis Pasteur was neither a physician nor a surgeon, but no one has done as much for medicine and surgery as he has.