Historical perspective of microbiology

1. HISTORICAL PERSPECTIVE
OF MICROBIOLOGY
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2. 1st Century B.C : Varo and Columella postulated that diseases were
caused by invisible organisms which they called “ Animalia
minuta”.
1546 : Fracastorius of Verona proposed a contagium vivum ( a
living germ) as a possible cause of infectious.
1676 : Bacteria was first observed by Antony Van Leeuwenhoek ,
using a single-lens microscope of his own design. He called them
“animacules” and published his observations in a series of letters
to the Royal Society.
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3. 1678 : Robert Hook developed compound microscope .
1745 : Needham believed in spontaneous generation of
microorganisms from the decomposing organic matter.
1762 : Von Plenciz suggested that each disease was caused by
a separate agent.
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4. 1769 : Spallanzani proved that organic contents of flask supported
the microbial growth when exposed to air.
1828 : The name ‘Bacterium’ was introduced by Christian Gottfried
Ehrenberg.
1835 : Augustino Bassi showed that the muscardine disease of silk
worms are caused by a fungus.
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5. • 1840 : Oliver Wendell Homes had concluded
that Puerperal sepsis ( presence of fever in a
woman within 6 weeks of giving birth ) , was
transmitted by the contaminated ( presence of
an infectious agent on a body surface) hands of
obstetricians, nurses and medical students and
this could be prevented by washing hands in
antiseptic solution.
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6. 1859 : Louis Pasteur demonstrated that the fermentation process is
caused by the growth of microorganisms.
1867 – Joseph Lister published his works on antiseptic surgery.
1876 – Robert Koch discovered anthrax bacillus.
1878 –Joseph Lister grew first pure culture of streptoccus lactis.
1879- Neisser discovered agent of gonorrhoea, neisseria
gonorrhoeae.
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7. 1882 – Robert Koch discovered tubercle bacillus.
1884 - Robert Koch published Koch’s postulates.
1885 - Pasteur inoculated Joseph Meister with attenuated
rabies virus.
1884 -Metchnikoff described phagocytosis and proposes the
“cellular theory of immunity”.
1890 - Ehrlich proposed the “humoral theory of immunity” -
antibodies
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8. 1905 : Robert Koch was awarded Nobel Prize for his research into
tuberculosis.
1910: Paul Ehrlich developed first antibiotic.
1892 - Ivanovsky discovered tobacco mosaic virus.
1898 - Beijerinck discovered foot and mouth virus.
1889 - Kitosato discovered tetanus bacillus and toxin.
1890 - Von Behring discovered diphtheria toxin and develops antitoxin.
1905 -Schaudinn and Hoffman discovered the syphilis spirochete.
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9. 1910 - Ehrlich developed salvarsan, a mercurial
agent effective in treating syphilis.
1928 - Fleming discovered the first antibiotic,
penicillin.
1941 - Beadle and Tatum proposed “one gene, one
protein” theory.
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10. 1944 - Avery, McLeod, and McMarty proved DNA
is the genetic material of cells.
1946 - Letterberg and Tatum demonstrated bacteria
can conjugate and exchange genetic material.
1953 - Watson and Crick determined the structure of
DNA.
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11. 1971 - Nathans, Smith, and Arber - discovered restriction
enzymes.
1975 - Dulbecco,, Temin and Baltimore discovered reverse
transcriptases.
1997 - Stanley Prusiner discovered prion – mad cow
disease
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12. 1874-Hansen discovered Lepra bacillus
1883 – Klebs and Loeffler discovered Diphtheria
bacillus
1886- Frankel discovered Pneumococus
1887- Weichselbum discovered Meningococcus
1888- Roux and Yersin discovered Diphtheria toxin
1889- Kitasato discovered Tetanus bacillus
1890 - Yersin discovered Plague bacillus
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13. Louis Pasteur : Known as Father of Microbiology.
Important Contributions :
1. Established that fermentation was caused by microbial
agents.
2. Developed methods and techniques of bacteriology.
3. Proved that all forms of life even microbes, arose only
from their like and not de novo ( from the beginning).
4. Developed steam sterilizer, autoclave and hot air oven.
5. Coined the term ‘vaccine’.
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14. 6.Studied on anthrax, chicken cholera and hydrophobia.
7.Introduced attenuated live vaccine for prophylactic use. He
demonstrated the protective role of anthrax vaccine in
animals.
8.Developed a vaccine for hydrophobia.
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15. Joseph Lister : Known as Father of Antiseptic Surgery.
Important Contribution: - Introduced antiseptic techniques
in surgery, involved the use of carbolic acid.
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16. Robert Koch : Known as Father of Bacteriology.
Important Contributions: -
1.Introduced methods of obtaining bacteria in pure cultures
using solid media.
2.Introduced staining techniques.
3.Discovered the anthrax bacillus, tubercle bacillus and
cholera vibrios.
4.Koch’s postulates
5.Koch’s phenomenon
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17. KOCH’S POSTULATES
Koch's postulates are the following:
• The microorganism must be found in abundance in all
organisms suffering from the disease, but should not be
found in healthy organisms.
• The microorganism must be isolated from a diseased
organism and grown in pure culture.
• The cultured microorganism should cause disease when
introduced into a healthy organism.
• The microorganism must be re-isolated from the inoculated,
diseased experimental host and identified as being identical
to the original specific causative agent.
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18. KOCH’S PHENOMENON
• Definition : It is a tuberculin reaction that occurs when a
culture of tubercle bacilli is injected into the skin of
subjects already infected with the disease.
• Example : Robert Koch observed that guinea pigs already
infected with tubercle bacillus responded with an
exaggerated inflammatory response with an injected with
the tubercle bacillus or its protein.
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19. Paul Ehrlich : Known as Father of Chemotherapy.
Important Contributions: -
1.Applied stains to cells and tissues for study of their
functions.
2.Reported the acid-fast nature of tubercle bacillus.
3.Proposed ‘side chain theory’ of antibody production.
4.Discovered ‘Salvarsan’And ‘Neosalvarsan, thus created new
branch of medicine known as chemotherapy.
5.Introduced methods of standardizing toxin and antitoxin.
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20. Reference :
Baveja C.P.( 2011) “Textbook of Microbiology”,3rd edition ,
Arya Publications, Page No.3-4.
Baveja C.P.( 2008) “Textbook of Microbiology”,2nd edition ,
Arya Publications, Page No.7-8
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21. KEY TERMS
• Pure culture = laboratory culture containing a single species
of organism.
• Culture = Growth and multiplication of microorganisms in
a culture medium
• Culture medium=Nutritional material prepared for the
growth of microorganisms in a laboratory
• Fermentation= process by which sugar is converted into
alcohol by microorganism
• Postulates = Basic principles
• Inoculated=introduced
• Conjugate=joined together in pairs
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22. KEY TERMS
• attenuated = make weaker
• Phagocytosis= Process in which phagocytes engulf and
digest microorganisms and cellular debris
• phagocytes = A cell that engulfs and digests debris and
invading microorganisms
• toxin = A poisonous substance produced during the
metabolism and growth of certain microorganisms
• Antitoxin = An antibody that can neutralize a specific toxin
• sterilizer= used to sterilize surgical instruments
• Autoclave = A device for heating substances above their
boiling point .
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23. KEY TERMS
• Sterilize : The procedure of making some object free of live
bacteria or other microorganisms
• Reverse transcriptase = polymerase
• prophylactic= preventive
• staining= coloring with a liquid dye
• acid-fast =Not easily decolorized by acid solutions
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