Transcript Micro History

Over 3.5 billion years of “microbes”;
only 400 years of Microbiology!
What were some early fundamental discoveries?
• First Microscopes
{Jannsen (1590), Hooke (1665), and van Leeuwenhoek (1676)}
• Debunking Spontaneous Generation
{Redi (1668), Needham (1748), Spallanzani (1767), Pasteur (1861)}
• Linking Microbes to Human Disease
{Rhazes (900), Semmelweis (1847), Snow (1854), Lister (1867), Koch (1876)}
• Discovering Immunity
{Jenner (1798), Pasteur (1881, 1885), Metchnikoff (1884), and von Behring (1890)}
• Agricultural and Environmental Microbiology
{Bassi (1835), Berkeley (1845), Beijerinck (1889), and Winogradsky (1887)}
First Microscopes
Zacharias Jannsen (1595),
Robert Hooke (1665):
first “cells” from cork;
Micrographia, 1665
First Microscopes
Antonie van Leeuwenhoek (1676): excellent simple microscopes;
discovered and observed microbes, called them “animalcules”.
Debunking Spontaneous Generation
Vitalism: life is independent of physical laws; there exists a special “life
force”; different life forms can arise from dead life; organic matter will
spontaneously generate new life; abiogenesis.
Mechanism: life is part of the physical world; formation of new organic
matter only requires proper physical, chemical and biological conditions;
living organisms are required to form new organisms of the same type;
“life begets life”.
covered
gauze
open
Fancesco Redi (1668): first scientific experiment to disprove abiogenesis.
Debunking Spontaneous Generation
Does abiogenesis still apply to microbes?
John Needham (1748): hot soup experiments always grew microbes; interpreted as
strong support for spontaneous generation; actually sloppy technique.
Lazzaro Spallanzani (1767): lengthy boiled broth experiments; microbes are in the air
and broth; others claimed boiling altered a “vital force”.
Louis Pasteur (1861): settled the issue; left flasks open to air, but flasks were
“swan-necked” so microbes could not settle into the broth.
Linking Microbes to Human Disease
Early Epidemiology
(epidemiology = study of factors determining and influencing the frequency and
distribution of disease, injury and other health related events.)
• Before Biological Inquiry: evil spirits, punishment for sins, miasma
• Abu-Bakr Muhammed al-Razi (Rhazes) (900): Arabic doctor; tested
relationship between urban location and rate of meat spoilage.
• Giralmo Fracostoro (1546): “contagion is an invisible infectious organism that
passes from one thing to another”; contact, fomites, and air cause spread.
• Ignaz Semmelweis (1847): examine the cause of high incidence of puerperal
sepsis (maternal fever after childbirth), blood poisoning; dirty doctors.
• John Snow (1854): traced the pattern in cholera epidemic in London to the
municipal water supply; imported country-side water lowered incidence.
The “Diseased” Wine of France
Louis Pasteur (1857):
Asked why wine soured
& to cure the industry.
Discovered yeast and
fermentation; first
evidence of microbial
metabolism.
Discovered acetogenic
bacteria form vinegar
from wine – souring.
Is this like a disease?
Napoleon III: Had to
keep the sailors
happy, but it kept
going sour (vinegar).
“Germ Theory of Disease”
Koch (1876 - 1910): He and his students discovered causative
agents of numerous infectious diseases of humans. Success
attributed to meticulous experimental design (Koch’s Postulates)
and development of pure culture technology within his lab group.
Franny E. Hesse proposed use of agar.
Koch’s
Postulates:
1) Observe
diseased mice.
2) Isolate microbe
in pure culture.
3) Infect healthy
mice to yield same
disease (anthrax)
4) Isolate same
microbe as before.
(Modified version:
see Box 1.2)
Discovering Immunity
(Immunology = Branch of biology
that studies the humeral and cellular
immune responses.)
• Edward Jenner (1798): cowpox as
smallpox vaccine (Latin vacca = cow)
• Louis Pasteur (1881, 1885):
cholera, anthrax and rabies vaccines
• Elie Metchnikoff (1884): phagocytosis
• Emil von Behring (1890): diptheria
and tetanus antitoxins produced.
Agricultural and Environmental
Microbiology
• Agostino Bassi (1835): silk worm fungal disease
• M.J. Berkeley (1845): potato blight fungus
• Martinus Beijerinck (1889, 1899): root nodules; tobacco mosaic
virus (first virus).
• Sergei Winogradsky (1887): N & S cycles
Find some of your own favorite 20th
century microbiologists!
Dr. Rita Colwell.
• Ecology of pathogens in
marine environments
• Director of the U. Maryland,
Centre for Marine
Biotechnology,
• President of the American
Society for Microbiology
• President of the American
Society for the Advancement
of Science.