micro 200 lec 2
Post on 30-May-2018
231 Views
Preview:
TRANSCRIPT
8/9/2019 Micro 200 lec 2
http://slidepdf.com/reader/full/micro-200-lec-2 1/46
PART II Pathways of PART II Pathways of Discovery in MicrobiologyDiscovery in Microbiology
The Historical Roots of The Historical Roots of MicrobiologyMicrobiology
8/9/2019 Micro 200 lec 2
http://slidepdf.com/reader/full/micro-200-lec-2 2/46
Anton van Leeuwenhoek and his
animalcules
Biogenesis vs Spontaneousgeneration
Germ Theory of Fermentation
Germ Theory of disease and
Kochµs Postulates
Immunization
8/9/2019 Micro 200 lec 2
http://slidepdf.com/reader/full/micro-200-lec-2 3/46
Robert Hooke (1665) - observed that plant material wascomposed of little boxes, he introduced the term ³ cell.´
Cell walls in cork tissueCell walls in cork tissue
Robert Hook and the developmentof the cell theory
8/9/2019 Micro 200 lec 2
http://slidepdf.com/reader/full/micro-200-lec-2 4/46
The first microscopic descriptions of microorganismsby Robert Hooke
blue mold growing on the surface of leather (round structures contain spores of the mold)
8/9/2019 Micro 200 lec 2
http://slidepdf.com/reader/full/micro-200-lec-2 5/46
the first to describe bacteria.A haberdasher Made >250 microscopes
Anton van Leeuwenhoek (1673)Anton van Leeuwenhoek (1673)
His insatiable curiosity about the natural world and his detaileddescriptions of what he saw that made him one of the founders of Microbiology«
8/9/2019 Micro 200 lec 2
http://slidepdf.com/reader/full/micro-200-lec-2 6/46
Simple microscope
Leeuwenhoek¶s drawingsof bacteria.
The animalcules«.
bacteria and protozoa
He found Ä animals appearing tome ten thousand times less thanthose which maybe perceived in
the water with the naked eye³
ÄIn the said matter, there weremany very little animalcules, very prettily a-moving...More over, the
other animalcules were in suchenormous numbers, that all the
water...seemed to be alive³
8/9/2019 Micro 200 lec 2
http://slidepdf.com/reader/full/micro-200-lec-2 7/46
Spontaneous generation (Abiogenesis)VS
Biogenesis
F rogs and worms arose spontaneously from ponds
living organisms could arise from non-living or decomposing matter.
Ancient Myths/ Spontaneous Generation
8/9/2019 Micro 200 lec 2
http://slidepdf.com/reader/full/micro-200-lec-2 8/46
Francesco Redi (1668)Francesco Redi (1668)--demonstrated that maggots appear on decayingdemonstrated that maggots appear on decayingmeat only when flies are able to lay eggs on the meat.meat only when flies are able to lay eggs on the meat.
8/9/2019 Micro 200 lec 2
http://slidepdf.com/reader/full/micro-200-lec-2 9/46
J ohn Needham (1745) revived theory of spontaneous generation at the microorganismlevel«.cooked meat will give rise to mirobes!!!
Anti-spontaneous generation
Lazaro Spallanzi ± boiled beef extracts in a flask (1hr) then sealed it.Microbes did not grow.......
Pro-spontaneous generation
J ohn Needham ± air is needed for spontaneous generation
8/9/2019 Micro 200 lec 2
http://slidepdf.com/reader/full/micro-200-lec-2 10/46
After 100 years..........
(1815-1873)
(1854)
8/9/2019 Micro 200 lec 2
http://slidepdf.com/reader/full/micro-200-lec-2 11/46
Felix Pouchet (1859)
-a french naturalist claimed to have carriedout experimentt conclusively proving thatmicrobial growth could occur without air contamination...
8/9/2019 Micro 200 lec 2
http://slidepdf.com/reader/full/micro-200-lec-2 12/46
-a French chemist
-yeast ferment sugars to alcohol
-high or low quality wine is dependenton the type of microbe/yeast
-bacteria can oxidize the alcohol toacetic acid.
-develop pasteurization
Louis Pasteur (1802-1895) and theGerm theory of Fermentation
8/9/2019 Micro 200 lec 2
http://slidepdf.com/reader/full/micro-200-lec-2 13/46
If fermentation products from grape juice
is the work of microorganisms«.thenmeat or broth putrefaction could be theresult of microbial contamination «
Louis Pasteur (1802-1895) and the
End of Spontaneous Generation Controversy
8/9/2019 Micro 200 lec 2
http://slidepdf.com/reader/full/micro-200-lec-2 14/46
Pasteurµs experiment
8/9/2019 Micro 200 lec 2
http://slidepdf.com/reader/full/micro-200-lec-2 15/46
Pasteurµs experiment
8/9/2019 Micro 200 lec 2
http://slidepdf.com/reader/full/micro-200-lec-2 16/46
The Link to the Germ theory of Disease
Pasteur saving the silk industry«..- proved that protozoans caused the silkworm disease- control the disease by raising caterpillars from eggs produced
by healthy moths
8/9/2019 Micro 200 lec 2
http://slidepdf.com/reader/full/micro-200-lec-2 17/46
The Link to the Germ theory of Disease
J oseph Lister (1860)
- father of modern surgery
- introduced the use of disinfectant to clean surgicalwounds in order to control
infections in humans
8/9/2019 Micro 200 lec 2
http://slidepdf.com/reader/full/micro-200-lec-2 18/46
Germ theory of Disease and Robert Koch
Robert Koch (1843 -1910)
- lifelong professional rival of Louis Pasteur
-a german physician
- isolated the bacterium that causes Anthrax... adisease decimating the herds of cattle and sheep in
Europe
8/9/2019 Micro 200 lec 2
http://slidepdf.com/reader/full/micro-200-lec-2 19/46
8/9/2019 Micro 200 lec 2
http://slidepdf.com/reader/full/micro-200-lec-2 20/46
Robert Koch and thedevelopment of Laboratory
techniques
Initially used sterile surface of cut/sliced boiled broth
Used gelatin in solidifying regular nutrient medium
Kochµs assistant suggested the use of agar
Richard Petri developed the petri dish
Tuberculosis ±Mycobacterium tuberculosis
Cholera- Vibrio choleraTyphoid fever - Salmonella typhi
Diptheria - Corynebacterium diptheriae
Tetanus - Clostridium tetani
8/9/2019 Micro 200 lec 2
http://slidepdf.com/reader/full/micro-200-lec-2 21/46
Pasteur and the Road toVaccination
Experiment 1: Pasteur injected healthy chickens with purecultures of cholera bacteria
Experiment 2.
Chickens in experiment 1 Uninoculated chicken
Young culture of cholera bacteria
injected
Remained alive andhealthy
Chickens died
Results - chickens did not get sick
Explanation - the inoculum used was several weeks old
8/9/2019 Micro 200 lec 2
http://slidepdf.com/reader/full/micro-200-lec-2 22/46
Pasteur called the avirulent cultures vaccine (fromlatin vacca = cow ) in recognition of the earlier work of Edward Jenner
Edward J enner vaccination(1798)
8/9/2019 Micro 200 lec 2
http://slidepdf.com/reader/full/micro-200-lec-2 23/46
Cowpox virus
8/9/2019 Micro 200 lec 2
http://slidepdf.com/reader/full/micro-200-lec-2 24/46
Pasteur also developed the rabies vaccine...
8/9/2019 Micro 200 lec 2
http://slidepdf.com/reader/full/micro-200-lec-2 25/46
Microbial Diversity and the Rise of GeneralMicrobial Diversity and the Rise of GeneralMicrobiologyMicrobiology
Beijerinck and Winogradsky-studied bacteria in soil and water and developed theenrichment culture technique for the isolation of representatives of various physiological groups:
8/9/2019 Micro 200 lec 2
http://slidepdf.com/reader/full/micro-200-lec-2 26/46
Ferdinand Cohn founded the field of bacteriologyand discovered bacterial endospores
8/9/2019 Micro 200 lec 2
http://slidepdf.com/reader/full/micro-200-lec-2 27/46
8/9/2019 Micro 200 lec 2
http://slidepdf.com/reader/full/micro-200-lec-2 28/46
Martinus Beijerinck (1851-1931)
The concept of enrichment culture technique
Isolated the first pure cultures of many soiland aquatic microorganisms.
- aerobic nitrogen fixing bacteria
-sulfate reducing bacteria
- root nodule bacteria
- L actobacillus species
- green algae
- basic tenets of virology
8/9/2019 Micro 200 lec 2
http://slidepdf.com/reader/full/micro-200-lec-2 29/46
- chemolithotrophy/chemoautotrophy
- nitrogen fixation.
Winogradsky
8/9/2019 Micro 200 lec 2
http://slidepdf.com/reader/full/micro-200-lec-2 30/46
8/9/2019 Micro 200 lec 2
http://slidepdf.com/reader/full/micro-200-lec-2 31/46
8/9/2019 Micro 200 lec 2
http://slidepdf.com/reader/full/micro-200-lec-2 32/46
Landmarks in Microbiology
8/9/2019 Micro 200 lec 2
http://slidepdf.com/reader/full/micro-200-lec-2 33/46
8/9/2019 Micro 200 lec 2
http://slidepdf.com/reader/full/micro-200-lec-2 34/46
8/9/2019 Micro 200 lec 2
http://slidepdf.com/reader/full/micro-200-lec-2 35/46
8/9/2019 Micro 200 lec 2
http://slidepdf.com/reader/full/micro-200-lec-2 36/46
8/9/2019 Micro 200 lec 2
http://slidepdf.com/reader/full/micro-200-lec-2 37/46
The Modern Era of The Modern Era of MicrobiologyMicrobiologyI n the middle to latter part of the twentieth
century, basic and applied microbiologyworked hand in hand to usher in the currentera of molecular microbiology. Figur e 1.17depicts some of the landmarks inmicrobiology in the past 65 years.
8/9/2019 Micro 200 lec 2
http://slidepdf.com/reader/full/micro-200-lec-2 38/46
Major new concepts in microbiologyemerged during this period, includingenrichment cultures
8/9/2019 Micro 200 lec 2
http://slidepdf.com/reader/full/micro-200-lec-2 39/46
S ome subdisciplines of applied
microbiology include medical microbiology,immunology, agricultural microbiology,industrial microbiology, aquaticmicrobiology, marine microbiology, andmicrobial ecology.
8/9/2019 Micro 200 lec 2
http://slidepdf.com/reader/full/micro-200-lec-2 40/46
S ome subdisciplines of basic microbiologyinclude microbial systematics, microbial physiology, cytology, microbial biochemistry, bacterial genetics, and molecular biology.
8/9/2019 Micro 200 lec 2
http://slidepdf.com/reader/full/micro-200-lec-2 41/46
- claimed that microorganisms could arise spontaneously from heated nutrient broth
-he demonstrated that inoculation witcowpox material provides humans wiimmunity to smallpox.
8/9/2019 Micro 200 lec 2
http://slidepdf.com/reader/full/micro-200-lec-2 42/46
S ugar converts to alcohol and lots of gas
8/9/2019 Micro 200 lec 2
http://slidepdf.com/reader/full/micro-200-lec-2 43/46
R obert Koch developed a set of postulatesto prove that a specific microorganism causesa specific disease:
8/9/2019 Micro 200 lec 2
http://slidepdf.com/reader/full/micro-200-lec-2 44/46
1 . The suspected pathogenic organismshould be present in all cases of thedisease and absent from healthy animals.
2. The suspected organism should be grownin p ur e c u lt ur e ²that is, a culture
containing a single kind of microorganism.
8/9/2019 Micro 200 lec 2
http://slidepdf.com/reader/full/micro-200-lec-2 45/46
3 . Cells from a pure culture of the suspectedorganism should cause disease in ahealthy animal.
4. The organism should be reisolated and
shown to be the same as the original.
8/9/2019 Micro 200 lec 2
http://slidepdf.com/reader/full/micro-200-lec-2 46/46
The Father of Modern S urgery
top related