Louis Pasteur

 

Louis Pasteur

Louis Pasteur, (born December 27, 1822, Dole, France—died September 28, 1895, Saint-Cloud), French chemist and microbiologist who was one of the most important founders of medical microbiology. Pasteur’s contributions to science, technology, and medicine are nearly without precedent. He pioneered the study of molecular asymmetry; discovered that microorganisms cause fermentation and disease; originated the process of pasteurization; saved the beer, wine, and silk industries in France; and developed vaccines against anthrax and rabies.

Pasteur’s academic positions were numerous, and his scientific accomplishments earned him France’s highest decoration, the Legion of Honour, as well as election to the Académie des Sciences and many other distinctions. Today there are some 30 institutes and an impressive number of hospitals, schools, buildings, and streets that bear his name—a set of honours bestowed on few scientists.

Early education

Pasteur’s father, Jean-Joseph Pasteur, was a tanner and a sergeant major decorated with the Legion of Honour during the Napoleonic Wars. This fact probably instilled in the younger Pasteur the strong patriotism that later was a defining element of his character. Louis Pasteur was an average student in his early years, but he was gifted in drawing and painting. His pastels and portraits of his parents and friends, made when he was 15, were later kept in the museum of the Pasteur Institute in Paris. After attending primary school in Arbois, where his family had moved, and secondary school in nearby Besançon, he earned his bachelor of arts degree (1840) and bachelor of science degree (1842) at the Royal College of Besançon.

Research career of Louis Pasteur

In 1843 Pasteur was admitted to the École Normale Supérieure (a teachers’ college in Paris), where he attended lectures by French chemist Jean-Baptiste-André Dumas and became Dumas’s teaching assistant. Pasteur obtained his master of science degree in 1845 and then acquired an advanced degree in physical sciences. He later earned his doctorate in sciences in 1847. Pasteur was appointed professor of physics at the Dijon Lycée (secondary school) in 1848 but shortly thereafter accepted a position as professor of chemistry at the University of Strasbourg. On May 29, 1849, he married Marie Laurent, the daughter of the rector of the university. The couple had five children; however, only two survived childhood.

Germ theory of fermentation

In 1854 Pasteur was appointed professor of chemistry and dean of the science faculty at the University of Lille. While working at Lille, he was asked to help solve problems related to alcohol production at a local distillery, and thus he began a series of studies on alcoholic fermentation. His work on these problems led to his involvement in tackling a variety of other practical and economic problems involving fermentation. His efforts proved successful in unraveling most of these problems, and new theoretical implications emerged from his work. Pasteur investigated a broad range of aspects of fermentation, including the production of compounds such as lactic acid that are responsible for the souring of milk. He also studied butyric acid fermentation.

In 1857 Pasteur left Lille and returned to Paris, having been appointed manager and director of scientific studies at the École Normale Supérieure. That same year he presented experimental evidence for the participation of living organisms in all fermentative processes and showed that a specific organism was associated with each particular fermentation. This evidence gave rise to the germ theory of fermentation.