HISTORY AND SCOPE OF MICROBIOLOGY

1. HISTORY AND SCOPE OF MICROBIOLOGY

2. History • 1665 Robert Hooke observed living plant tissues (20X mag.) • “Little boxes” or Cells • Used simple magnifying lens • Suggested all living things are made of cells

3. Hooke's Microscope 1665 Antonie van Leeuwenhoek was inspired by this publication

4. Antonie van Leeuwenhoek(1677) (“layu-wen-hook”) • First observation of living cells (200-300X mag.) • “Animalcules” • Single lens Microscope (Self made)—simple microscope • Tooth plaque • Rain water • Diarrheal feces

5. Antonie van Leeuwenhoek • Bacteria • Protozoa • Sperm cells • Blood cells • Microscopic worms

6. Antonie van Leeuwenhoek’s microscope 3-4” microscope Required good lighting and patience

8. Spontaneous Generation • The idea that life could arise spontaneously from nonliving matter • Ex: Toads and Mice could arise from soil • Until the 18th century this believe existed

9. History (cont.) • 1668 Francesco Redi • 1st one to disprove spontaneous generation

10. Francesco Redi’s experiments with meat uncovered covered No maggots Maggots Disproved that maggots arise from decaying meat!!

11. British clergyman John Needham’s experiments (1745) • Proved (??) spontaneous generation in chicken broth • Heated Nutrient Fluids and poured them into covered flasks Turbid broth Hot Mutton gravy “...my phial swarm’d with life...”

12. Italian priest Lazzaro Spallanzani (1765) • Similar to Needham’s Experiments • He showed that heating a sealed flask of meat broth prevented growth of organism • Skeptics claimed—lack of O2 prevented growth!!

13. The Golden Age of Microbiology! • Louis Pasteur (finally disproved spontaneous generation after many years of debate) • Robert Koch (proof of germ theory) • Other pioneers in Microbiology

14. Pasteur—Father of microbiology • 1857- Louis Pasteur saves France’s wine industry • Napoleon III begged Pasteur (a chemist by training) to help solve a problem • Sailors were mutinying b/c their wine was spoiling after only a few weeks at sea • Pasteur armed with his trusty microscope accepted the challenge

15. Luis Pasteur

16. Louis Pasteur (1861) • Spontaneous Generation finally disproved • Boiled broth in long-s-shaped necked flasks (unsealed) • Remained sterile • Proved that microorganisms are present in air, but air does not create microbes • Beginning of the golden age of microbiology

17. Swan neck flask experiment disproved spontaneous generation(1861)

18. History (cont.) • 1861 Pasteur • Proved Microorganisms are present in nonliving matter • Microbes can be destroyed by heat • Aseptic Technique • Fermentation mediated by yeast, not air • Pasteurization to prevent wine and beer spoilage (by bacteria)

19. 1857-Louis Pasteur saves France’s wine • Good wine contained yeast • Sour wine contained bacterium (Bacteria that use alcohol and produce acetic acid spoil wine by turning it to vinegar (acetic acid). • He reasoned that if wine is heated to destroy the harmful bacteria it wouldn’t spoil (process known as Pasteurization)

20. Pasteur’s Tomb in the Crypt of the Pasteur Institute in Paris

21. Germ Theory of Disease • Pasteur proposed that wine spoiling in an analogy for disease (bacterial growth made the wine “sick”) • He hypothesized in 1857 that microorganisms are responsible for infectious diseases

22. Edward Jenner (country doctor) • Milkmaid didn’t get smallpox b/c they contracted the milder form of cowpox • Immune system cannot distinguish btw cowpox/smallpox • Scratched a farmboy w/ a needle bearing fluid from cowpox • Small pox Vaccine • -Vacca-cow • Vaccination w/ cowpox provided immunity for smallpox

24. Immunity Protection from a disease from vaccination

25. Robert Koch (1843-1910) • German country physician who developed microbiology into a science • Developed pure culture techniques (used potato slices to grow bacteria) developed agar later on • Proof of the germ theory • Work with anthrax • Koch’s postulates

26. Bacillus anthracis

27. Pure Culture Key to Studying Microbes Definition: Pure culture is a population of organism, all of which are the progeny of a single organism -In nature, microbes almost never occur as pure cultures

28. AGAR • Is a complex polysaccharide derived from seaweed • Was suggested by Fannie Hesse wife of Koch’s co-worker Walther Hesse • “why do your jellies and pudding stay solid in warm weather”? • AGAR-AGAR had been used as a gelling agent in Asia for centuries • Fannie learned to use AGAR-AGAR from a Dutch neighbor in New York who spent time in Asia

29. Koch’s postulates • Specific microorganism is present in all cases of the disease • Organism can be obtained in pure culture outside of the host • Organism when re-inoculated into host causes the same symptoms • Organism can be isolated in pure culture from experimentally infected host

30. Koch’s findings • Koch and his coworkers discovered that bacteria caused • TUBERCULOSIS • CHOLERA • DIPTHERIA • TYPHOID FEVER • GONORRHEA • PNEUMONIA

31. Hungarian doctor Ignaz Semmelweis (1818-1865) • Taught medicine in Vienna • No one connected germs w/ disease yet • Puerperal fever “childbirth fever” caused 25-30% mortality • Nearby obstetric hospital had only a 2% death rate

33. Ignaz Semmelweis (cont.) • He made some observations • Medical Students working on cadavers moved from the dissecting room to the maternity ward • Midwives • Stayed only in maternity ward

34. Ignaz Semmelweis (cont.) • Ordered students to wash hands and medical instruments in chlorinated lime • Mortality dropped to 1.3% • By 1848, 0% mortality

35. Paul Ehrlich-hospital dermatologist • Chemotherapy-Treatment using chemical substances • 1910 Paul Ehrlich -”Magic bullet” • Salvarsan (arsenic derivative) • Preparation 606 • Syphilis

36. Alexander Fleming –scottish researcher--1928 • Discovered Penicillin (fungus) by accident • Was convinced that nasal mucus had antibacterial effects • Left his Staphylococcus culture on an agar plate for 2 weeks-went on vacation-came back &found mold on his plate which prevented bacterial growth (a mycology lab underneath him had this rare spore drift)

39. Founders of Microbiology (Review) • First observed microbes—Leeuwenhoek • Proved living cells can arise only from other living cells---Pasteur • Confirmed the Germ Theory of Disease --Koch

40. Scope of microbiology

41. Microbiology • Bacteria • Fungi • Viruses • Immunology

42. Bacteria • Medical importance • Gastroenteritis • Syphilis • Tetanus • Lyme disease • Plague

43. Bacteria (cont.) • Industrial importance • Food supplements • Amino acids & Vitamins • Organic solvents • Acetone

44. Bacteria (cont.) • Pharmaceutical importance • Antibiotics • polymyxin • Hormones • Insulin

45. Biotechnology and Recombinant DNA • Biotechnology: • The use of microorganisms, cells, or cell components to make a product • Foods, antibiotics, vitamins, enzymes • Recombinant DNA Technology: • Insertion or modification of genes to produce desired proteins

46. Figure 9.1.1

47. Bacteria (cont.) Environmental importance Biodegradation Oil spills Wastewater treatment

48. Figure 9.1.2

49. Gram positive S. aureus

50. Gram negative E. coli