LOUIS PASTEUR – THE GERM HUNTER
We all notice the word “pasteurized” on the milk packets or containers that we buy. Pasteurized milk is the milk that is free of germs. The technique that is used to kill bacteria in liquid food is called Pasteurization. The name for this process comes from the last name of a French scientist Louis Pasteur, who discovered this technique. Louis Pasteur was well known for discovering principles of vaccination, pasteurization and microbial fermentation. He is often known as the “Father of Bacteriology”. Let us know more about this great microbiolgist who contributed tremendously to the field of microbiology.
Louis Pasteur was born in a poor Catholic family on 27th December, 1822, in Dole, Jura, France. He was the third son of Jean Joseph Pasteur and Jeanne-Etiennette Roqui. His father was a tanner who once served as a sergeant major during the Napoleonic Wars. His family moved to Arbois in 1827 and there he entered primary school in the year 1831. Pasteur was an average student in his early years, he did not show much interest towards academics. He had passion towards sketching and fishing. He made pastels and portraits of his family and friends at the age of 15 and these paintings are now kept in the museum of the Pasteur Institute, Paris.
Pasteur joined Royal de Besançon college in the year 1839 and earned his Bachelors degree in Arts in the year 1840. He took his Bachelors degree in Science in the year 1842. He joined École Normale Supérieure, a teachers college in Paris, in 1842 and received his Masters degree in Science in 1845 and later he also took a degree in physical sciences. In the year 1847, he took his doctorate in sciences.
He was appointed as a physics professor at the Dijon Lycée in the year 1848 but he quit the job as he wanted to work as a chemistry professor at the University of Strasbourg. In 1854, Pasteur became the dean of new faculty of sciences at Lille University. Here he began his studies on fermentation. He conducted several experiments and demonstrated that fermentation occurs due the growth of microbes. Most of the scientists in those days believed that the growth of microrganisms was due to spontaneous generation but Louis Pasteur cleared their misconception by proving that biogenesis was the reason behind the growth.
Pasteur was chosen to be the director of scientific studies at the École Normale Supérieure in 1857. He worked here untill 1867. In 1862, he became a professor of physics, chemistry and geology at École nationale supérieure des Beaux-Arts. He served as a professor until his resignation in 1867.
His studies on fermentation showed that growth of microorganisms spoilt beverages like wine, beer and milk. Inorder to prevent spoilage, he invented a process where beverages were heated to temperature between 60 and 100 oC. This process killed most of the bacteria present in the liquid. Pasteur patented this method and it came to be known as pasteurization in the year 1865.
His work on vaccination began in the year 1879 while studying a disease called as chicken cholera. He attenuated(heat killed) a culture of virus that was causing cholera and accidentally exposed some chickens to this heat killed virus. He observed that they became resistant to actual virus causing cholera. This laid the foundation for his study on vaccination.
Rabies was found to be the most dreadful disease in the nineteeth century. Therefore Pasteur started working along with his colleagues to develop a vaccine against it. They did experiments on infected rabbits and developed a vaccine, which was tested on fifty dogs. But the vaccine was yet to be tested on humans. Although Pasteur was not a licensed medical practitioner, he took a chance and administerd the vaccine on young boy bitten by a rabies dog. The boy did not develop any symptom of the disease even after three months.
He established Pasteur Institute in the year 1887 and served as director in it for the rest of his life. This institute started its first course of microbiology which was titled ‘Cours de Microbie Technique’ (Course of microbe research techniques). This was the first course of microbiolgy ever taught to the World.
Pasteur was awarded with Rumford Medal by the Royal Society of London in 1856 for his discovery of the nature of racemic acid and its relations to polarised light. He was awarded with Monyton Prize, the Jecker Prize and the Alhumbert Prize by the French Academy of Sciences. In 1874, he received the Copley Medal for his work on fermentation. He became a foreign member of the Royal Netherlands Academy of Arts and Sciences. In 1895, he won microbiology’s highest Dutch honor in Arts and Sciences and the Leeuwenhoek medal.
While Pasteur was working at the University of Strasbourg, he fell in love with Marie Laurent, who was the daughter of University’s rector. They got married in the year 1849. The couple had five children. Only two of their kids survived to adulthood and the other three died of diseases. These tragedies strengthend Pasteurs aim to find a solution for infectious diseases. Pasteur suffered from a series of strokes from the year 1868 and he got severly affected with the stroke he got in 1894. He never recovered fully after that and he died on 28th september 1895.