History of Microbiology

VOCABULARY Fermentation: the enzymatic degeneration of carbohydrates in which the final electron acceptor is an organic molecule (contains carbon). For example, ATP is synthesized by phosporylation (adding phosphate) and oxygen it is not required. Fermentation is the process that yeasts use to convert sugars to alcohol in the absence of air. Pasteurization: the process of mild heating to kill particular spoilage microorganisms or pathogens. Anaerobic: without oxygen

Aristotle Spontaneous Generation

Virgil Bees grow from honey and flies grow from meat

The Romans Used a magnifying lens called “Flea glasses”

Zacharias Janssen Invented the first compound microscope

The First Microscope

Galileo Improved the microscope, Improved the telescope

First Telescope

Antoni Van Leeuwenhoek Improved the simple microscope to a magnification of 270x Described first microbes.

Antoni Van Leeuwenhoek

Basic Shapes COCCI RODS SPIRALS Staphylococci Streptococci

Arrangements Pairs: diplococci, diplobacilli Clusters: staphylococci Chains: streptococci, streptobacilli

Robert Hooke Coined the term “cells”

Robert Hooke

The Debate Over Spontaneous Generation The hypothesis that living organisms arise from nonliving matter is called spontaneous generation. According to spontaneous generation, a “vital force’ Forms life. The alternative hypothesis, that the living organisms arise from preexisting life, is called biogenesis.

Francisco Redi Biogenesis Theory: Maggots do not grow from meat.

Francisco Redi

Evidence Pro and Con 1668: Francisco Redi filled six jars with decaying meat. Conditions Results 3 jars covered with fine net No maggots 3 open jars Maggots appeared From where did the maggots come? What was the purpose of the sealed jars? Spontaneous generation or biogenesis?

John Needham Put boiled nutrient broth into covered flasks.

1745: John Needham put boiled nutrient broth into covered flasks. Conditions Results Nutrient broth heated, then placed in sealed flask Microbial growth From where did the microbes come? Spontaneous generation or biogenesis?

1861: Louis Pasteur demonstrated that microorganisms are present in the air. Conditions Results Nutrient broth placed in flask, heated, not sealed Microbial growth Nutrient broth placed in flask, heated, then sealed No microbial growth Spontaneous generation or biogenesis?

Louis Pasteur

The Theory of Biogenesis Pasteur’s S-shaped flask kept microbes out but let air in. Figure 1.3

Edward Jenner First vaccine: Smallpox

Edward Jenner

Rudolf Virchow Cell Theory All living things are composed of cells. Cells are the smallest working units of living things. 3. All cells come from preexisting cells by cell division (biogenesis theory).

Agostino Bassi Silkworm disease is caused by a fungus

Louis Pasteur

Spontaneous Generation Theory Aristotle thought that the mice grew from the grain and hay, and he coined the term “Spontaneous generation” Virgil: bees grew from honey and that flies grew from meat. Redi: maggots in meat were caused by flies laying eggs; they only grew on the meat in which the jars were not covered. John Needham believed in spontaneous generation; boiled nutrient broth to kill all microbes, put a non-sterile cork in the flask, found that the broth grew microbes. Louis Pasteur: made a glass flask with an “S” shaped bend in it so that bacteria could not enter into it but air could get in. He placed chicken broth in the flask and boiled it so that it was sterile and observed that there was no bacterial growth in the broth.

Sheep Vaccine for Anthrax

Robert Koch

Koch’s Postulates Obtain the disease causing microbe from the sick animal via a sample. Isolate this microbe in pure culture. Inoculate a healthy animal with this pure culture, and the healthy animal should develop the same disease. Re-isolate the microbe from the second animal. If it is the same microbe obtained from the first animal, this proves the etiology (cause) of the disease.

Joseph Lister

Operation using Lister's carbolic spray invented in 1869

Ignaz Semmelwise Puerperal fever could be drastically cut by use of hand washing standards in obstetrical clinics.

Paul Ehrlich First Antibiotic: For syphilis

Paul Ehrlich

Von Behring Invented diphtheria antitoxin

Ross Mosquitoes transmit malaria

Metchnikoff Discovered White Blood Cells and phagocytosis: Began field of immunology

Alexander Fleming

The Birth of Modern Chemotherapy 1928: Alexander Fleming discovered the first antibiotic. He observed that Penicillium fungus made an antibiotic, penicillin, that killed S. aureus. 1940s: Penicillin was tested clinically and mass produced. Figure 1.5

Chain and Florey Purified penicillin as a medicine

Rebecca Lancefield

Lancefield’s Streptococcus Classification

Frederick Griffith Discovered DNA

Watson and Crick Detailed the structure of human DNA.

DNA Structure Deoxyribose (sugar) A, T, C, G (nucleic acids) Phosphate (to form the bonds)

Jacob and Monod Role of mRNA in protein synthesis

Protein Synthesis

Delbruck and Hershey Structure of viruses

Virus

Tonegawa Antibody genetics

Prusiner Discovery of prions

Prions

SELECTED NOBEL PRIZES IN PHYSIOLOGY 1901 Behring diphtheria antitoxin 1902 Ross malaria transmission 1905 Koch TB bacterium 1908 Metchnikoff phagocytosis 1945 Fleming, Chain, Florey penicillin 1969 Delbruck, Hershey viral replication 1987 Tohegawa antibody genetics 1997 Prusiner prions