History of Microbiology Timeline

History of Microbiology

• 500 BCE – Greek philosophers propose the miasma theory to explain the origin of diseases through “bad air.”

• 1668 – Francesco Redi disproves spontaneous generation by showing maggots come from flies, not decaying meat.

• 1674 – Antonie van Leeuwenhoek observes bacteria and protozoa using a handmade single-lens microscope.

• 1765 – Lazzaro Spallanzani uses boiled, sealed broth experiments to further disprove spontaneous generation.

• 1857 – Louis Pasteur demonstrates that microorganisms cause fermentation, laying the foundation for germ theory.

• 1861 – Pasteur’s swan-neck flask experiment proves microbes originate from the environment, not spontaneously.

• 1865 – Joseph Lister introduces antiseptic surgery using carbolic acid to sterilize wounds and instruments.

• 1876 – Robert Koch formulates Koch’s postulates and identifies Bacillus anthracis as the cause of anthrax.

• 1881 – Koch develops the pure culture technique using solid agar to isolate bacterial colonies.

• 1882 – Koch discovers Mycobacterium tuberculosis, establishing the cause of tuberculosis.

• 1883 – Koch isolates Vibrio cholerae, confirming the bacterium as the cause of cholera.

• 1883 – Elie Metchnikoff discovers phagocytosis, identifying the role of white blood cells in immunity.

• 1884 – Hans Christian Gram develops the Gram stain to differentiate bacteria into Gram-positive and Gram-negative.

• 1885 – Louis Pasteur tests the first rabies vaccine successfully on a human subject.

• 1892 – Dmitri Ivanovsky shows infectious agents in tobacco mosaic disease can pass through bacterial filters.

• 1898 – Martinus Beijerinck coins the term “virus” and describes it as a new type of infectious agent.

• 1928 – Alexander Fleming discovers penicillin from Penicillium notatum, the first antibiotic.

• 1931 – Ernst Ruska and Max Knoll invent the electron microscope, enabling visualization of viruses.

• 1940 – Florey and Chain develop mass production techniques for penicillin during World War II.

• 1944 – Avery, MacLeod, and McCarty prove DNA, not protein, is the molecule responsible for heredity.

• 1946 – Joshua Lederberg and Edward Tatum demonstrate bacterial conjugation, revealing horizontal gene transfer.

• 1955 – Wendell Stanley and others determine the structure of tobacco mosaic virus, advancing virology.

• 1970 – Hamilton Smith and Daniel Nathans discover restriction enzymes that cut DNA at specific sites.

• 1983 – Kary Mullis invents the polymerase chain reaction (PCR), revolutionizing DNA amplification.

• 2002 – CRISPR-Cas systems are identified in bacterial genomes, laying the groundwork for gene editing tools.

• 2019 – Emergence of SARS-CoV-2 triggers the COVID-19 pandemic, catalyzing global microbiological and virological research.