Transcript Slide 1

MICROBIOLOGIST IN HISTORY
Classical
Greeks sound mind and sound body
(350 BCE)
Aristotle (300 BCE) mice originated from seeds + dark + straw
Varro(200 BCE) Dz caused by invisible creatures
Virgil (40 BCE) bees originated from honey and flies from meat.
Dark Ages (400-1200) Bacon (1220): Franciscan Monk, agreed that invisible living creatures produce disease. He initiated the science of optics for magnification.
Renaissance Europe Fracastorius (1546, Venice) A monk who figured out syphilis is transmitted by living germs through direct contact, “Seminaria morbi”=seeds of illness.
Reformation Europe Leeuwenhoek (1632-1723, Holland) invented the SIMPLE microscope “animalcules” and defined rods, spheres, and spirals.
(1600-1650)
Redi (1675) Refuted the theory that maggots originated from exposed meat by covering the jar with cheesecloth.
Hooke (1678) developed the COMPOUND microscope
Reason Europe
Needham (1749): a Priest/Scientist who believed Spont. Gen. Invented the boiled broth flask
(1700-1850)
Spallanzani (1800) Also a Priest/Scientist, did NOT believe Spont. Gen. sealed necks of boiled broth in flasks
Bassi (early 1810) Proved that a fungus caused a disease in silkworms in France and Italy.
Barthelemy (1825) Observes anthrax is transmitted from infected sheep to cattle by contact.
Oliver Wendell Holmes (1840, American poet-philosopher) “Contagiousness of Puerperal Fever”
Schultz Schwann, Schroeder (1850)Passed air through strong acids, heat, and filters and then into boiled broth, got no growth.
Rayer, Pollender, and Davaine (1850’s) observed rod bacteria in anthrax infected blood of cattle.
Brauell (1857) Found anthrax bacilli in the blood of a human, and transmitted the disease to sheep.
Pouchet (1859): Agreed with Needham Argued that “Vital Force” in air was required for spontaneous generation.
Golden Age
Louis Pasteur (1860) Gooseneck Flask, chicken cholera vaccine and rabies vaccine, “ferments”, PASTEURIZATION 63° C for ½ hour, isolated cause of silkworm Dz.
(1860-1890)
Semmelweis (1861) Introduced antiseptic techniques, decreasing childbirth deaths.
Davaine (1863) Proved infected cattle blood transmits anthrax, healthy blood does not.
Lister (1870) Sprayed operating rooms with phenol, Made the first culture media, used gelatin.
Obermeier (1873) Observed spirochete bacteria in the blood of a human with relapsing fever and reproduced the disease in another human by injecting the contaminated blood.
Tyndall (1875) Proves that microbes are suspended in dust, not the air itself (e.g. spores)
Koch (1885) Developed gelatin agar, methods for staining bacteria. Isolate anthrax in pure culture
KOCH’S POSTULATES The organism must always be found in the diseased animal, but not in the healthy ones.
The organism must be isolated from diseased animals and grown in pure culture away from the animal.
The isolated organism must produce the disease when inoculated into susceptible animals
The organism should be reisolated from the experimentally infected animals.
Problems with Koch’s Postulates: What if organism won’t grow on lifeless culture? (Viruses, blood-feeding bacteria, leprosy, etc)
Kieselguhr (1891)Invented the Berkefeld filter made from diatomaceous earth.
Iwanowski (1892) The first to record the transmission of an infection in tobacco by a suspension filtered through a bacteria-proof filter, proving the existence of an organism smaller than bacteria.
Loeffler and Frosch (1898) Found that Foot and Mouth disease of cattle was caused by an organism smaller than bacteria-proof filters (a virus).
Beijernick (1898) Considered these infectious agents to be living, but fluid, and introduced the term “virus” (“poison”) to describe them.
Rous (1911) Discovered a virus than produced malignant tumors in chickens
Twort and Herelle (during WW II) Independently discovered the viruses which multiply in bacteria, and called them bacteriophages.
Stanley (1935) Demonstrated that plant viruses consist of only nucleic acid and protein, tobacco mosaic virus.
Rivers (Rockefeller Institute, 1940’s) RIVERS POSTULATES: Not all agents are culturable; cytopathic effect can confirm its presence; samples must be transported properly; organisms need not
be present to cause disease (intoxification).
Hirst (1940’s) Developed the tern “hemagglutination”, after seeing influenza virus agglutinating chicken red blood cells.
Ellis and Delbruck (1940’s) Study of the one-step growth cycle, allowing study of a single virus to interact with a single cell, instead of whole colonies.
Edward Jenner (1749-1823) Noticed that milkmaids who got cowpox were immune to smallpox, so used cowpox to vaccinate individuals susceptible to smallpox.
Salmon and Smith (1884-1886) Used heat-killed cultures to make hog cholera vaccine for swine.
Metchnikoff (1880’s) Developed the cellular theory of protection.
Border (1880’s) Proposed the humoral, or specific, antibody concept of immunity. Known today as “immunoglobins”.
Ehrlich (mid to late 1800’s) Pioneered the concept of antimetabolites, e.g. penicillin.
Domagk (1935) Reported that Prontosil had a dramatic effect of streptococcal infections.
Florey and Chain (1940’s, due to WW II) Isolated and characterized Fleming’s penicillin. Demonstrated the practical use of penicillin for infections.
Griffith (1943) Smooth pneumococci capsules (and heat-killed smooth) were deadly, rough were not. Smooth DNA + Live rough also = death
Avery (1940’s) Demonstrated that the transforming factor of Griffith’s study was DNA.
Hershey and Chase (1952) Demonstrated that viral nucleic acid contains all the information for virus replication.
Watson and Crick (1950’s) Developed the double-helix model of DNA structure,
Nirenberg and Ochoa (1960’s) Worked out the nature of the triplet RNA base sequences corresponding to the codon signals for all amino acids.