C hair of M icrobiology, V irology, and I mmunology

1. Chair of Microbiology, Virology, and Immunology THE HISTORY OF MICROBIOLOGY. CLASSIFICATION AND STRUCTURE OF MICROORGANISMS. Lecturer As. O. B Kuchmak

2. Lecture schedule • History of Microbiology. • Classification of bacteria. • Structure of bacterialcell • The physiology of microorganisms.Growth, reproduction and respiration of bacteria.

3. Why Study Microbiology? • Pharmaceuticals • Vaccines/Antibiotics • Biotechnology • Bioremediation • Pathogenicity • Fundamental Biology

4. MicrobiologyThe study of microorganisms • Microorganisms living things too small to be seen with the unaided eye • Microorganisms = Microbes

5. Microorganisms Divided into six groups • Bacteria • Archae • Algae • Fungi • Protozoa • Viruses

6. History of Microbiology • Microbes discovered >300yrs • Known to man during the mid 1800s • Period of progress began & continues to the present

7. Periods of microbiology development • Morphologic • Physiologic • Prophylactic

8. Morphological period inmicrobiology history (XVII middle of age). It is also called micrographycal period, as the study of microorganism came only to description of their dimensions and forms. Biological properties and their significances for man still a long time remained incomprehensible.

9. Experimental phase • Leeuwenhoek • Pasteur • Koch • Lister

10. Before 17th century, study of microbiology was hampered by the lack of appropriate tools to observe microbes. • Robert Hooke: In 1665 built a compound light microscope and used it to observe thin slices of cork. Coined the word cell. • Anton van Leeuwenhoeck: In 1673 was the first person to observe live microorganisms which he called “animalcules” (bacteria, protozoa), using single-lens microscopes that he designed. He observed 50,000 different specimens, reported findings to the Royal Society of London

12. Edward Jenner ( 1796)  Smallpox immunity / Vaccine

14. Pasteur’s Contributions: • Pasteurization: Developed a process in which liquids are heated (at 65oC) to kill most bacteria responsible for spoilage. • Disease Causes: Identified three different microbes that caused silkworm diseases. • Vaccine: Developed a vaccine for rabies from dried spinal cords of infected rabbits. • Directed Pasteur Institute until his death in 1895.

15. French Chemist Pasteur (1861)

17. Joseph Lister (1859): Used disinfectant to treat surgical wounds, greatly reducing infection rates. Considered the father of antiseptic surgery.

19. Robert Koch (1876): • First person proved that microorganisms caused diseases • Only specific microorganisms caused specific diseases • Studied anthrax  affects cattle & humans • Proved that Bacillus anthracis causes anthrax in cattle. • Later identified bacterium that causes tuberculosis.

21. Study of viruses • Iwanoski (1892) studying diseases of tobacco plants • Discovered TMV • Filterable viruses

23. Prophylactic periodAfter 1914 Classic Metchnikov's researches defineda prophylactic periodinmicrobiology history. The Patriarch of world and Ukrainian microbiology - I. Metchnikov

24. Paul Ehrlich (1910): Search for “magic bullet”. • Discovered salvarsan, an arsenic derivative, was effective against syphilis. (1st synthetic drug to come in to widespread use) • Alexander Fleming (1928): Discovered that penicillin produced by the mold Penicillium notatum was able to prevent microbial growth. • Penicillin came into use 10 yrs later -By the 1940s known as the “wonder drug” • Rene Dubos (1939): Discovered two antibiotics (gramidin and tyrocidine) produced by bacterium (Bacillus brevis).

28. Classifications system. Bergey's Manual of Determinative Bacteriology – the "bible" of bacterial taxonomy. There are such levels of microorganisms’ organization: Species – Genus – Family – Class – Division – Kingdom

29. 35 of the major groups of bacteria are distinguished primarily on morphological characteristics, namely: cell shapes (rods, cocci, curved, or filament forming); spore production; staining reactions; motility. Other groups are defined based on their metabolism, or combinations of morphological and physiological characteristics.

30. Some of the Major Groups of Bacteria in Bergey's Manual

31. What is a bacterium?

32. Bacteria (Sing. Bacterium) • Small, single-celled (unicellular) organisms. • Procaryotes: “Before nucleus”. Lack the following structures: • Nuclear membrane around DNA • Membrane bound organelles • Mitochondria • Chloroplasts • Golgi apparatus • Endoplasmic reticulum • Lysosomes

34. Bacterial Identification and Classification • Shape - cocci, bacilli, spiral • Arrangement - single, pairs, chains, clusters • Size • Gram-positive vs. Gram-negative • Aerobic vs. anaerobic • Physical/structural characteristics • Biochemical characteristics • DNA analysis

35. The Dimension of Bacteria Relative size of a bacterial cell compared to other cells including viruses.

36. Coccus - round Bacillus - rod - Fusiform, coccobacilli Spirillum - corkscrew - Flexible, undulating - spirochetes - Curved - vibrios Gross morphology of bacteria • Size - 1 to 10 mm - aids in identification • Shape

37. Coccus Tetrad Diplococcus Sarcinae Streptococcus Staphylococcus Cocci groupings

38. Chains of cocci Streptococcus pyogenes

39. Clusters of cocci Staphylococcus aureus Sputum smear

40. Bacillus shaped bacteria Pseudomonas aeruginosa Escherichia coli

41. Bacillus shaped bacteria Fusobacterium

42. Bacillus chains Bacillus anthracis

43. Palisades arrangement Corynebacteriumdiphtheriae

44. Curved bacteria Vibrio cholerae Campylobacter

45. Curved bacteria Spirilla Borrelia burgdorferi

46. Bacterial surface structures

47. Cell Envelope • Cytoplasmic membrane • Cell wall Cell wall-less bacteria • No peptidoglycan layer • Cell membrane contains sterols for stability Mycoplasma pneumoniae

48. Cytoplasmic Membrane • Phospholipid bilayer • “Fluid mosaic” model • Embedded proteins for active transport • Enzymes for energy generation • Photosynthetic pigments

49. Cell membrane Peripheral Membrane Protein Phospholipid Integral Membrane Protein Peripheral Membrane Protein

50. Function of Cytoplasmic Membrane • Selective permeability to different molecules. • Active transport aided by permease. • Play a role in DNA replication. • Cell wall biosynthesis. • Mesosomes ----- cell division.