Louis Pasteur
Pioneer Microbiologist; Developer of Pasteurization
Louis Pasteur was born on December 27, 1822, in Dô1e, eastern France. He was a mediocre student in primary school but showed promise at painting, and his early ambition was to teach art. However, by 1843 his university work was good enough to place him at the École Normale Supérieure, a teacher training school in Paris, from which he received his doctorate in chemistry in 1847.
Pasteur’s early research concerned tartaric acid, a byproduct of wine making. He analyzed a solution of tartaric acid that was optically inactive (did not rotate polarized light). He found that the solution contained two kinds of tartaric acid molecules that were mirror images of each other. The molecules were stereo isomers, alternative forms of the same compound in which the atoms are arranged differently. Pasteur separated the two kinds and determined that they had distinct properties; he thus founded stereo chemistry, the study of the arrangement of atoms within compounds.
In the early 1860s, Pasteur studied fermentation in beer and wine making. In 1864 he found that souring of a fermented product can be prevented if it is heated to kill harmful microscopic agents. This began the practice of heating foods to kill harmful microorganisms, particularly tuberculosis bacilli in dairy products, a process now called pasteurization after its inventor.
In the 1880s Pasteur focused on microbial virulence, borrowing ideas from the success of EDWARD JENNER, who in the 1790s had developed a vaccine against smallpox by injecting people with weakened cowpox bacteria. This gave Pasteur the idea that a “safe attack” on disease could be developed using weak cultures of specific germs to vaccinate healthy animals. Serums he developed against chicken cholera, anthrax, and rabies brought him international renown.
In 1888, Pasteur established the Pasteur Institute, an agency devoted to biological research, in Parts. He headed the institute until he died in Paris on September 28, 1895
Louis Pasteur’s Legacy
Pasteur’s scientific insight and innovative experimentation contributed to improvements in human health and paved the way for further progress in the battle against infectious diseases.
Prior to pasteurization, health problems related to food spoilage were rampant. As pasteurization became accepted, the storage time of milk increased and the incidents of food poisoning decreased.
Pasteur’s fermentation research and the development of pasteurization influenced surgical procedures during his lifetime. British surgeon JOSEPH LISTER read Pasteur’s publications in 1865 and hypothesized that microorganisms cause infection in wounds, just as microorganisms cause souring in liquids. Lister introduced antiseptic procedures to combat infection and sepsis. His innovations spread through Europe quickly, and the incidence of fatal post surgical infection decreased drastically.
Pasteur founded the field of stereo chemistry, the study of the three dimensional structure of molecules and compounds. The concepts underlying stereo chemistry are important in the pharmaceutical industry, as exemplified by the drug thalidomide. Thalidomide occurs in two mirror image stereoisomers, only one of which is harmful to a developing fetus. The other is completely benign. Stereochemical analysis is applied in fields beyond medicine, such as material technology; to help understand how molecules and compounds will interact with each other.
Pasteur’s final legacy was left with those who have fought the war against infectious diseases. Pasteur provided a general theory to guide physicians’ research: the concept that infectious diseases are caused by microbial agents. Pasteur also established standard experimental techniques subsequently used by others to identify treatments for infectious diseases. His revolutionary work with anthrax, cholera, and rabies laid the groundwork for the development of numerous other vaccines against debilitating diseases.
Louis Pasteur – 1822-1895