History of Microbiology

Robert Hooke

○ First recorded observation of cells

○ While examining a thin slice of cork, he saw tiny box-like structures that reminded him of small rooms or “cellula.”

○ He coined the term “cell.”

Anton Van Leeuwenhook

Known as the “Father of Microbiology”

○ Was able to visualize:

■ Bacteria (from dental scrapings/paprika)

■ Rainwater/pond water

■ Human bodily fluids

■ Tiny organisms he called “animalcules”

Theory of spontaneous generation

New cells can come from nothing

John Needham

○ Proponent of abiogenesis theory

■ Life came from non-living things.

Example: People used to think maggots just popped out of rotting meat.

Francisco Redi

Disproved spontaneous generation

■ Tested the idea that maggots came from meat.

by itself.”

■ Put meat in two jars:

● Open jar → maggots appeared.

● Closed jar (with gauze) → no maggots on the meat (they stayed on the gauze instead).

■ Proved that maggots come from flies, not from meat itself.

Germ Theory of Disease (Biogenesis Theory)

New cells come from pre-existing cells

Rudolf Virchow

○ Completed the Classical Cell Theory

○ Main points:

■ All living things are made of cells

The cell is the basic unit of structure and function

■ All cells come from pre-existing cells (Virchow’s contribution)

Louis Pasteur

○ Showed that microorganisms cause specific diseases

○ Developed the aseptic technique

○ Invented pasteurization

Home method

63 degree Celsius for 30 mins

High temp, Short time

72 degree Celsius for 25 seconds

Ultra high temp

140 degree celsius for 4 seconds

Benjamin Martin

○ Germ Theory of disease

○ Proposed that contagious diseases are caused by tiny living organisms

○ Challenged the old Miasma Theory (diseases from “bad air”)

○ Replaced the idea of body imbalances as the main cause of illness

Robert Koch

○ Identified Bacillus anthracis (anthrax)

○ Identified Mycobacterium tuberculosis (tuberculosis)

○ Identified Vibrio cholerae (cholera)

○ Koch’s Postulates

■ The organism must be present in every case of the disease.

■ It must be isolated and grown in pure culture.

■ The cultured organism must cause the same disease when introduced into a healthy host.

■ The same organism must be re-isolated from the experimentally infected host.

Paul Ehrlich

○ Salvarsan (Compound 606 / Arsphenamine)

■ Known as the “magic bullet”

■ First effective treatment for syphilis

Alexander Fleming

○ Discovered that Penicillium mold killed bacteria.

Howard Florey and Ernst Chain

Developed penicillin into the first widely used antibiotic.

John Enders

○ Father of Modern Vaccines

○ First to cultivate viruses in cell line cultures

Otto Friedrich Muller

Organized bacteria into genera and species

○ Guided by the system of Carolus Linnaeus

John Tyndall

○ Tyndallization

■ Also called Intermittent Sterilization

■ Method used to destroy endospores

Gerhard Domagk

○ Discovered as the first sulfonamide drug; Prontosil (Sulfamidochrysoidine).

○ Effective against streptococcal infections

○ First widely used antimicrobial drug before penicillin

Selman Waksman

○ Isolated from the soil bacterium Streptomyces griseus

○ First antibiotic found to be effective against Mycobacterium tuberculosis

Coined the term “antibiotic.”