Microbiology Introduction PDF

Microbiology 4203 Dr Ian Kaye Big Heads Anton von Leeuwenhoek No knowledge of microbes. Access to primitive but first true 20x lens microscope shows enlarged invertebrates, not microbes. Coined term Animalcules. Rotting meat and maggots. Meat (dead) spontaneously grew maggots. Likely viewed w...

Microbiology 4203 Dr Ian Kaye Big Heads Anton von Leeuwenhoek No knowledge of microbes. Access to primitive but first true 20x lens microscope shows enlarged invertebrates, not microbes. Coined term Animalcules. Rotting meat and maggots. Meat (dead) spontaneously grew maggots. Likely viewed worms, sperm, some protozoa, fleas. Equipment Fake! I'm curious...... Robert Hooke 1650 Spontaneous generation goes out the jar Redi Francesco 1668 Flies (not dead meat) cause maggots. Counters ideation that a dead bull (meat) left in a shed attracts bees (it doesnt) Experiment requires three flasks; meat exposed to open air and flies grew maggots, meat closed to sealed air and flies did not grow maggots, and meat exposed to gauze filtered air did not grow maggots. Therefore only the flies could cause maggots. SG is refuted by Redi. The Big Fight John Needham 1745 Refutes Redi SG idea. Repeats Redi’s experiment but heats the meat broth in the flask closed to air and flies. Bacteria grow as do other microbes. Dead meat causes life using a natural vital force Hint: (bacteria survive heat). SG is theorized. A set back? I can feel it in the air.... Spallanzani, Lazzaro (1760) Refutes Needham. Closely repeats Needham’s experiment, but boils sealed glass containing meat broth. The Maggots and other microbes do not reappear. Air dust and flies (living) cause growth of maggots. SG is not theorized. Progress? Is Air the source of bacteria Big guns Louis Pasteur 1857 Refutes Spallanzani (1760). Theorizes that dust not air causes microbes to grow in boiled meat broth. He uses a flask designed with a dust trapping loop which still allows air to flow after passing through a water seal.After a year, no growth of microbes or maggots. SG does not occur. Past your eyes..... Further theorizes that all foods boiled enough (not yeast) and sealed from dust do not spoil easily (Pasteurization of wine). Publishes Germ Theory of disease. Suggests all germs cause disease. Not enough experimentation to link specific germs with specific disease, but does link vibrio cholera with puerperal fever. Rabies vaccine? Germ Theory ? Applicable today. The germ theory is a fundamental tenet of medicine that states that microorganisms, which are too small to be seen without the aid of a microscope, can invade the body and cause disease. To vaccinate or not? Jenner, Edward (1796) Uses living subjects. No ethical laws at this time. Observes that milk maids exposed to cow pox pus do not contract smallpox. Inoculates healthy boy with cox pox pus, waits for cowpox to run its course, and infects same boy with smallpox pus. The boy does not develop smallpox disease. Process termed Vaccinia. True father of Microbiology Koch, Robert (1880) Specifically links microbe to disease. Cholera 1879, Anthrax 1881, Rabies 1885Postulates published, Links exact organism anthrax, tuberculum, vibrio to disease. Koch's life Koch's Postulates Are you convinced? What about Syphilis, Leprosy, Viruses, and Prions? Viruses require a living host cell, embryonated fibroblasts, or cell culture (primary, diploid, and continuous) We didn’t start the fire...... Its in the DNA Hershey and Chase (1953) Hershey–Chase experiments were a series of experiments conducted in 1953 by Alfred Hershey and Martha Chase that helped to confirm that DNA is genetic material. Theory that DNA transformation is pathogenic not protein. Spontaneous generation again..... Urey -Miller 1952 They recreate conditions to produce amino acids of life Spontaneous generation Recreates conditions on primitive earth using inorganic gasses to form organic amino acids Its your turn Helicobacter Pylori (Wilson) - live in nonacid mucin layer and carbonate buffered to survive. Several examples online notes Practice Homework: Does HIV cause AIDS even though there is no animal model?