Anton von Leeuwenhoek

1674

First person to view living microbes.

Beginning of Microbiology

Lazzaro Spallanzani

1767

Proves that spontaneous generation cannot be correct

Boiled items won't spoil unless exposed to air

Edward Jenner

1798

1st vaccination of smallpox

Ignaz Semmelweis

1840

Suggests physicians should wash their hands during childbirth

Louis Pasteur

1857  Yeast causes firmentation 

Developed pasteurization

Marks the beginning of the Golden Age of Microbiology (1857-1914)

1861 provides final disproof of the theory of spontaneous generation

coins the term aerobic and anaerobic

Developes vaccines for cholera and rabies

Joseph Lister

1867

Uses phenol to treat surgical wounds

This served as proof that microorganisms caused infections

Robert Koch

1876 Germ Theory of Disease= diseases are caused by infectious agents

Koch's Postulates= begins steps towards pathogen identification

1881 Develops the concept of achieving pure cultures using solid media

1884 formalizes Koch's Postulates

Paul Ehrlich

1912

Creates a cure for syphilis

First specific chemotherapeutic agent

Alexander Fleming

1929

Discovers the first antibiotic, penicillin

Florey and Chain

1940

Mass production of penicillin

Chain and Abraham

1940

Discovers the first evidence of antibiotic-resistant bacteria

Watson and Crick

1953

Develop the 3D model of DNA structure

Nathans, Smith, and Arber

1971

Discover restriction enzymes

Creates the age of genetic engineering

Berg, Boyer, and Cohen

1973

Produces the 1st genetically-engineered organisms

Bishop and Varmus

1977

Discovers retroviral oncogenes (cancer-causing genes)

Prusiner

1982

discovers a new type of infectious agent, prion

French Anderson

1993

1st successful gene therapy

Progression of disproving the Theory of Spontaneous Generation

1668, Redi challenged the idea that maggots arose spontaneously from rotting meat

1674, von Leeuwenhock views microorganisms.

1745, Needham performed a series of experiments on boiled broths. Believing that boiling would kill all living things, he showed that when sealed right after boiling, the broths would cloud, allowing the belief in spontaneous generation to persist.

1768, Spallanzani boiling the broth in a sealed container with the air partially evacuated to prevent explosions. Although he did not see growth, the exclusion of air left the question of whether air was an essential factor in spontaneous generation.

1861, Pasteur boils the broth in a swan neck bottle finally proving that spontaneous generation does not exist. Creating the new Theory of Biogenesis.

Importance of the disproof of the Theory of Spontaneous Generation

Semmelweis- washing hands

Lister- redusing infection with phenol

Koch- pure cultures & identifying causative agent

Germ Theory of Disease- diseases cause infections

Ehrlich- antibodies are responsible for immunity

Fleming, Florey, Chain, Abraham- penicillin

Operon Theory

Proteins performing coordinated functions are encoded by genes that are located next to each other on the prokaryotic chromosome and that these sets of coordinated genes have the same operator (on/off switch)

-Jacob and Monod-

Germ Theory of Disease

Diseases are caused by infectious microorganisms