The Role of Louis Pasteur in Microbiology

Louis Pasteur (1822–1895)

Louis Pasteur (1822–1895) was born in the village of Dole, France on December 27, 1822, the son of humble parents. His father was a tanner. He was originally trained as a chemist, but his studies on fermentation led him to take interest in microorganisms. His discoveries revolutionized medical practice, although he never studied medi cine.

Fig. Father of Microbiology Louis Pasteur
Fig. Father of Microbiology Louis Pasteur

Louis Pasteur is known as ‘"Father of Microbiology" because his contribution led to the development of microbiology as a separate scientific discipline.

Contributions of Louis Pasteur in Microbiology 

  • Coined the term "Microbiology": For the study of living organnisms of microscopic size.
  • Proposed germ theory of disease: Louis Pasteur established that putrefaction and fermentation was the result of microbial activity and that different types of fermentations were associated with different types of microoganisms (1857).
  • Disapproved theory of sponta neous generation: Louis Pasteur disapproved the theory of sponta neous generation in 1860–1861 in public controversy with Pouchet who was a proponent of spontaneous generation. In a series of classic experiments in the swan-necked flasks, Pasteur proved conclusively by demonstrating the the ubiquity of microorganisms that all forms of life, even microbes, arose only from their like and not de novo.
  • Developed sterilization techniques and developed the steam sterilizer, hot-air oven and autoclave in the course of these studies.
  •  Developed methods and techniques for cultivation of microorganisms.
  • Studies on pebrine (silkworm disease), anthrax, chicken cholera and hydrophobia.
  • Pasteurization: Louis Pasteur deviced the process of destroying bacteria, known as pasteurization.
  • Coined the term "Vaccine": It was Pasteur who coined the term vaccine for such prophylactic preparations.
  • Microbiology in cholera; Discovery of the process of attenuation and chicken cholera vaccine: An accidental observation that chicken cholera bacillus cultures left on the bench for several weeks lost their pathogenic property but retained their ability to protect the birds against subsequent infection by them, led to the discovery of the process of attenuation and the development of live vaccines.
  • Microbiology & Anthrax; Developed live attenuated anthrax vaccine: Pasteur attenuated cultures of the anthrax bacillus by incubation at high temperature (42–43°C) and proved that inoculation of such cultures in animals induced specific protection against anthrax. The success of such immunization was dramatically demonstrated by a public experiment on a farm at Pouilly-le-Fort (1881) during which vaccinated sheep, goats and cows were challenged with a virulent anthrax bacillus culture. All the vaccinated animals survived the challenge, while an equal number of unvaccinated control animals succumbed to it.
  • Microbiology as a vaccine: Developed rabies vaccine in 1885. He did not know that rabies was caused by a virus but he managed to develop a live attenuated vaccine for the disease.
  • Noticed pneumococci: Pneumococci were first noticed by Pasteur and Sternberg  independently in 1881.

Scientific Development of Microbiology

The development of microbiology as a scientific discipline dates from Louis Pasteur, perfection on microbiological (microbiology) studies by Robert Koch, the introduction of antiseptic surgery by Lord Lister and contributions of Paul Ehrlich in chemotherapy.