History of microbiology

History of microbiology

1. Microbiology

2. UNIT 1 History and Significance of Microbiology

3. It is estimated that microbes contain 50% of the biological carbon and 90% of the biological nitrogen on Earth . Found everywhere; geothermal vents in the ocean depths; arctic ice; skin Microbiology often has been defined as the study of organisms and agents too small to be seen clearly by the unaided eye —that is, the study of microorganisms. However, some microorganisms, particularly some eukaryotic microbes, are visible without microscopes. For example, bread molds and filamentous algae are visible to the naked eye, as are the two bacteria Thiomargarita and Epulopiscium .

4. What is Microbiology? Microbes , or microorganisms are minute living things that are usually unable to be viewed with the naked eye. What are some examples of microbes? Bacteria, fungi, protozoa, algae, viruses Some are pathogenic Many are beneficial

5. Microbiology defined as the study of organisms too small to be seen with the naked eye. These organisms include viruses, bacteria, algae, fungi, and protozoa. Microbiologists are concerned with characteristics and functions such as morphology, cytology, physiology, ecology, taxonomy, genetics, and molecular biology. Defining Microbiology

6. Microbes make the Universe There are > 5 x 10 30 types Microbes in the world Humans have intimate relation with Microbes > 90% of the cells in our Body are Microbes

7. History of Microbiology 1674, Antoni van Leeuwenhoek (Dutch) described live microorganisms that he observed in teeth scrapings, rain water, and peppercorn infusions.

8. Anton van Leeuwenhoek 1674 - 1st person to actually see living microorganisms “ wee animalcules” （ Leeuwenhoek ） 1632-1723

9. Louis Pasteur 1922 - 95 Contributed best in Microbiology Sterilization Hot Air oven Autoclave Anthrax vaccine Rabies vaccine Built the Pasteur Institute (founded- 4 th June 1887, Inaugurated- 14 th Nov 1888)

10. Louis Pasteur Louis Pasteur considered the father of Modern Microbiology

11. Robert Koch 1843 - 1910 A German scientist Formulated the Bacteriological techniques Staining Methods Discovered the Mycobacterium and Vibrio cholera Koch’s postulates- Causal relationship between a microorganism and a specific disease

12. 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 reisolated from the inoculated, diseased experimental host and identified as being identical to the original specific causative agent.

13. Waksman Professor of microbiology at Rutgers University. In 1952 was awarded the Nobel prize in physiology or medicine for the part he played in the discovery of the antibiotic streptomycin, which is produced by a soil bacterium.

14. Organisms included in the study of Microbiology 1 . Bacteria 2. Protozoans 3. Algae 4. Parasites 5. Yeasts and Molds Fungi 6. Viruses Bacteriology Protozoology Phycology Parasitology Mycology Virology

15. Bacteria - what comes to mind? Diseases Infections Epidemics Food Spoilage Only 1% of all known bacteria cause human diseases About 4% of all known bacteria cause plant diseases 95% of known bacteria are non-pathogens

16. Microbes Benefit Humans 1.Bacteria are primary decomposers - recycle nutrients back into the environment (sewage treatment plants) 2. Microbes produce various food products cheese, pickles, sauerkraut, green olives yogurt, soy sauce, vinegar, bread Beer, Wine, Alcohol

17. Microbes are also capable of causing many diseases Pneumonia Whooping Cough Botulism Typhoid Fever Measles Cholera Scarlet Fever Mumps Syphilis Gonorrhea Herpes 1 Chlamydia Tuberculosis Herpes 2 Meningitis Tetanus RMSV Strep Throat Lyme Disease AIDS Black Plague Diarrhea Gangrene

18. Major Events 1546 Fracastoro suggests that invisible organisms cause disease. 1590–1608 Jansen develops first useful compound microscope . 1674 Leeuwenhoek discovers “ animacules ”. 1688 Redi refutes spontaneous generation of maggots. 1765–1776 Spallanzoni attacks spontaneous generation. 1786 Miller produces first classification of bacteria. 1798 Jenner introduces cowpox vaccination for smallpox. 1838–1839 Schwann and Schleiden propose the Cell Theory . 1835–1844 Bassi discovers silkworm disease caused by fungus. 1847–1850 Semmelweis introduces antiseptics to prevent disease . 1857 Pasteur describes fermentation . 1861 Pasteur disproves spontaneous generation.

19. 1867 Lister publishes on antiseptic surgery. 1876–1877 Koch demonstrates anthrax caused by Bacillus anthracis . 1880 Laveran discovers Plasmodium , the cause of malaria. 1881 Koch cultures bacteria on gelatin; Pasteur develops anthrax vaccine . 1882 Koch discovers Mycobacterium tuberculosis . 1885 Pasteur develops rabies vaccine; Escherich discovers Escherichia coli . 1887 Richard Julius Petri develops petri dish (plate). 1887-1890 Winogradsky studies sulfur and nitrifying bacteria. 1889 Beijerinck isolates root nodule bacteria. 1890 Von Behring’s antitoxin for diptheria and tetanus 1894 Kitasato and Yersin discover Yersinia pesits . 1895 Bordet discovers complement. 1896 van Ermengem discovers Clostridium botulinum . 1899 Beijerinck proves virus causes tobacco mosaic disease.

20. 1900 Reed proves yellow fever transmitted by mosquito . 1902 Landsteiner discovers blood groups. 1903 Wright and others discover antibodies. 1905 Schaudian and Hoffmann show Treponema pallidum causes syphilis. 1906 Wassermann develops complement fixation test for syphilis. 1910 Ricketts shows Rocky Mountain spotted fever caused by microbe. 1911 Rous discovers a virus can cause cancer. 1915-1917 D’Herelle and Twort discover bacterial viruses. 1921 Fleming discovers lysozyme. 1923 First edition of Bergey’s Manual. 1928 Griffith discovers bacterial transformation. 1929 Fleming discovers penicillin. 1931 Van Niel studies photosynthetic bacteria.

21. 1933 Ruska develops electron microscope. 1935 Domagk discovers sulfa drugs. 1937 Chatton divides living organisms into prokaryotes and eukaryotes . 1941 Beadle and Tatum propose one-gene-one-enzyme theory. 1944 Waksman discovers streptomycin. (Nobel Prize in 1952) 1949 Enders, Weller, and Robbins grow poliovirus in human tissue culture. 1953 Watson and Crick propose DNA double helix . 1955 Jacob and Wollman discover F-factor plasmid. 1959 Yalow develops radioimmunoassay. 1961 Jacob and Monod propose lac operon. 1962 First quinolone synthesized. 1970 Arber and Smith discover restriction endonucleases. 1979 Insulin synthesized using recombinant DNA; smallpox officially declared eradicated. 1977 Woese divides procaryotes into Bacteria and Archaea.

22. 1980 Development of scanning tunnelling microscopes. 1982 Recombinant Hepatitis B vaccine developed . 1983-1984 HIV isolated and identified by Gallo and Montagnier ; Mullis develops PCR technique . 1986 First vaccine developed by genetic engineering approved for human use. 1990 First human gene therapy testing begun. 1992 First human trials of antisense therapy. 1995 Chicken pox vaccine approved for U.S. use; Haemophilus influenzae genome sequenced. 1996 Methanococcus jannaschii and yeast genomes sequenced. 1997 Largest known bacterium, Thiomargarita namibiensis , discovered . 2000 Discovery that Vibrio cholerae has two chromosomes. 2001 Anthrax bioterrorism attack in New York, Washington D.C., and Florida. 2002 Infectious poliovirus synthesized from basic chemicals. 2003 SARS outbreak in China . 2005 “Super resistant” HIV strain isolated in New York City.

23. What is microbiology Study of Micro-organisms: Organisms that EXIST as Single Cells or cell clusters and must be viewed individually with the aid of a Microscope 1. EXIST (Webster definition)To continue to be, have life; live HALLMARKS OF LIFE METABOLISM (nutrient uptake, biomass, waste output) DIFFERENTIATION ( Bacillus spp. Caulobacter ) REPRODUCTION (binary fission) COMMUNICATION (Pseudomonas aeruginosa) EVOLUTION (antibiotic resistance, pathogens)

24. Metabolism Take in nutrients from the environment glucose, lactose, other sugars, fats=lipids, proteins, toxic wastes, oils and petrol Assimilate the nutrients into BIOMASS DNA, proteins, carbohydrates and complex carbohydrates, lipids Release waste products into the environment gases, alcohols, acids and organic compounds

25. Differentiation— to form distinct structures Caulobacter spp. Vegetative cells versus stalk cells K.C. Keiler M. Dworkin

26. Differentiation— to form distinct structures Bacillus spp. endospore forming cells Anabaena spp. Cyanobacteria forming heterocysts

27. Reproduction To generate progeny of ones same type A bacterium duplicates its DNA and forms daughter cells via binary fission Yeast duplicates its DNA and forms a daughter cell via budding , or mates with another yeast cell and produces haploid progeny. J. Pitocchelli E. Hettema

28. Communication interaction with other cells—response to other cells Vibrio fischeri and Lantern fish Kolter and Losick AMNH--NYC

29. www.med.umich.edu Communication bacteria communicate with each other using a chemical language called “ Quorum Sensing ."

30. 2 . KEYWORD single CELLS (OR cell clusters) CHARACTERISTICS THAT MICROORGANISMS HAVE THAT MAKE THEM TRUE CELLS CELL MEMBRANE –barrier that separates the inside of the cell from the outside NUCLEUS OR NUCLEIOD – location of genetic information (DNA) CYTOPLASM –location of the machinery for cell growth and function MACROMOLECULES – proteins, nucleic acids, lipids, polysaccharides

31. exist as SINGLE cells (OR cell clusters) We are multicellular creatures—made up of many cells What makes one of our cells different from a microbial cell?? A single microbial cell can have an independent existence —our specialized cells need to interact with other cells in order to carry out their cellular functions for the good of the entire organism.

32. What organisms are considered to be microbial cells and studied in microbiology BACTERIA FUNGI ALGAE PROTOZOA Viruses (although not a cellular entity but an intracellular pathogen) Prions (a biochemical anomaly—misfolded proteins) Helminths Worms (multicellular)

33. Taxonomy The study of phylogenetic relationships between organisms (The sorting of all living things based on their related or differentiating features) KINDOM the highest level in classification ( eg . Bacteria) PHYLUM related classes ( eg . Firmicutes ) CLASS related orders ( eg . Bacilli) ORDER related families ( eg . Lactobacillales ) FAMILY related genera ( eg . Streptococcaceae ) GENUS closely related species ( eg . Streptococcus ) SPECIES organisms sharing a set of biological traits and reproducing only with their exact kind ( eg . S. pneumoniae ) Further classifications especially with bacteria: Strain —organisms within a species varying in a given quality ( eg . S. pneumoniae D39; virulent strain) Type —organisms within a species varying immunologically

34. Taxonomy: Initially not easy to classify microorganisms based on their behaviour and appearance Advancements in DNA amplification and DNA sequencing has greatly helped The phylogenetic relationships between microorganisms can be determined by sequencing the 16S and 18S ribosomal RNA of the organisms in question. (ribosomal RNA —structural RNA of the ribosome that plays a role in protein synthesis)

35. Phylogenetic classification of micro-organisms Universal Ancestor Algae Fungi Protozoa Prokaryotic Eubacteria Archaeabacteria Eukaryotic

36. Phylogenetic classification of micro-organisms EUBACTERIA most abundant of the bacteria found in soil, water and animal digestive tracts ARCHAEACTERIA live in extreme conditions (temperature, pH etc ) mostly anaerobic (unable to live in the presence of oxygen) EUKARYOTES algae : live in soil and water, contains chlorophyll for photosynthesis, has a cell wall fungi : yeast, molds. Lack chlorophyll and obtains energy from organic compounds in soil and water, has a cell wall protozoa : colorless, lacks a cell wall, ingests other organisms or organic particles

37. Prokaryotic and Eukaryotic Cells

38. Two Basic Cell Types: Prokaryotic vs. Eukaryotic Cells

39. The Discovery of Cells Prokaryotic before nucleus Eukaryotic true nucleus

40. Two Basic Types Remember….cells are the basic unit of life for ALL living things. There are two basic types of cells: Prokaryotic cells – found in bacteria Eukaryotic cells – found in protists , fungi, plants and animals

41. Eukaryotic cells Muscle cardiac cells fibroblast blood

42. Eukaryotic cell Cytopla s m = cytosol + organelles

43. Eukaryotes Has a nucleus with a nuclear envelope Bigger and more complex than prokaryotes Have membrane bound Organelles ( golgi , ER, lysosomes… etc ) DNA – double-stranded and forms chromosomes (highly organized) Can be uni - OR multicellular organisms Ex: animals, plants, fungi

44. Eukaryotic Cells

45. Prokaryote Introduction Prokaryotes are much more diverse in both habitat and metabolism than the eukaryotes. However, prokaryotes are not very diverse in body shape or size. Nearly all prokaryotes are single-celled. Differentiation into different cell types almost never occurs in prokaryotes. Two major groups: the Eubacteria (sometimes just called Bacteria) and the Archaea (or Archaebacteria ). Very different genetically.

46. Prokaryote Cell Shapes Spheres ( cocci ), rods ( bacilli ), spirals ( spirilla )

47. Prokaryotes NO nucleus NO membrane bound organelles (just ribosomes) ALL are unicellular Smaller than eukaryotic cells Forerunner to eukaryotic cells (smaller and more simple) DNA – single, circular double-stranded DNA (as genetic material) Ex: ALL Bacteria

48. A Prokaryotic Cell

49. Flagella and Pili

50. Characteristics Shared Perform the same basic functions Surrounded by cell/plasma membrane to control what enters and leaves the cell “Filled” with cytoplasm Contain ribosomes to make protein Contain DNA to give the general instructions for the cell’s life Contain all four biomolecules (lipids, carbs, proteins, and nucleic acids) Similar Metabolism Can be unicellular

51. Major Differences between prokaryotic and eukaryotic micro-organisms Prokaryotes 1. Non-membrane bound nucleoid region DNA-one circular molecule one chromosome Haploid-One copy of a gene Plasma membrane does not contain sterols Reproduction—simple binary fission 6. Membrane bound organelles are absent. Eukaryotes 1. Membrane bound nucleus containing DNA DNA-linear molecules arranged to form several chromosomes Diploid-Two copies of a gene Plasma membrane contains sterols Reproduction—meiosis and mitosis Presence of membrane bound organelles such as chloroplasts and mitochondria

52. What Makes Eukaryotic Cells Different? Much larger Much more complex Contain a true nucleus to house the genetic material (DNA) Linear DNA packaged into chromatin found inside the nucleus Contains specialized structures in the cytoplasm called organelles to carry out various functions Not all have a cell wall

53. What Makes Prokaryotic Cells Different? Much smaller Less complex No true nucleus Circular DNA that is found in the cytoplasm No organelles found in the cytoplasm Surrounded by a cell wall

54. What does size have to do with it? Prokaryotic cells are much smaller than eukaryotic cells. Why? Smaller surface area to volume allows nutrients to easily and quickly reach inner parts of the cell. Eukaryotic cells are larger and can not pass nutrients as quickly. They require specialized organelles to: carry out metabolism provide energy transport chemicals throughout the cell