Discovery of Bacteria

Discovery of Bacteria

Role of Antonie Van Leeuwenhoek.

In 1673 A Dutch Scientist “Antonie Van Leeuwenhoek” discovered bacteria and other microbes. He was the first to report microbes such as bacteria and protozoa. He used a simple microscope to describe bacteria and protozoa with accurate drawings and descriptions and called these small creatures as animalcules. He firstly observed small creatures in rain water, and then confirmed these in saliva, vinegar, infusions and other substances.

Role of Louis Pasteur.

Louis Pasteur confirmed the existence of microbes through his work. Pasteur made many discoveries in the field of medicine and microbiology. He made many vaccines against anthrax, fowl cholera and rabies.

He also introduced the method of pasteurization and fermentation. He proved that microorganisms could cause diseases.

Role of Robert Koch.

Robert Koch formulated the germ theory of disease. He isolated typical rod shaped bacteria with squarish ends (Bacillus anthracis) from the blood of sheep that had died of anthrax. He also discovered bacteria that caused tuberculosis and cholera.

Postulates of germ theory of disease.

He formulated four postulates which are the main pillars of the germ theory of disease.

1.      A specific organism can always be found in association with a given disease.

2.      The organism can be isolated and grown in pure culture in the laboratory.

3.      The pure culture will produce the disease when inoculated into susceptible animal.

4.      It is possible to recover the organism in pure culture from experimental infected animal.

Robert Koch and his colleagues also invented many techniques such as

·         Inoculation.

·         Insulation.

·         Media Preparation.

·         Maintenance of pure cultures.

·         Preparation of specimen for microscopic examinations.