Chapter 01 Lecture 1 A Glimpse of History . Science of microbiology born in 1674 . Antony van Leeuwenhoek (1632–1723) • Drapery merchant • Made simple magnifying glass • Studied lake water • Observed ‘animalcules’! . Robert Hooke • Also credited with discovery • Described ‘microscopical mushroom’ (common bread mold) in 1665 Importance of Microorganisms . Microorganisms are Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. foundation for all life on earth Lens . Have existed for ~3.5 Specimen holder billion years . Plants, animals, Focus screw modern microorganisms all evolved from ancestral bacteria Handle . Our life depends on their activities © Kathy Talaro/Visuals Unlimited 1.1. The Dispute Over Spontaneous Generation . Theory of Spontaneous Generation • “Life arises spontaneously from non-living material” • Theory had supporters and detractors • Detractors included – Francesco Redi – Louis Pasteur – John Tyndall • Each contributed to disproving the theory 1.1. The Dispute Over Spontaneous Generation . Italian biologist and physician Francesco Redi . Demonstrated worms on rotting meat came from eggs of flies landing on meat (1668) • Placed meat in two jars • Covered one jar with gauze • Gauze prevented flies from depositing eggs • No eggs no worms . Took another 200 years to convincingly disprove spontaneous generation of microorganisms • One reason: conflicting results between laboratories 1.1. The Dispute Over Spontaneous Generation . Multiple contributions helped define . In 1749, John Needham demonstrated boiled broths still produced microorganisms . In 1776, Father Spallanzani contradicted Needham’s results • Boiled broths longer; sealed flasks by melting necks • Broths remained sterile unless neck cracked . Controversy still unsolved • Some argued heating destroyed “vital force” necessary for spontaneous generation 1.1. The Dispute Over Spontaneous Generation . French chemist Louis Pasteur . Considered “father of modern microbiology” . Demonstrated air is filled with microorganisms . Filtered air through cotton plug • Observed trapped microorganisms • Many looked identical to those found in broths 1.1. The Dispute Over Spontaneous Generation . Developed swan-necked flask • Boiled infusions remained sterile despite opening to air • Ended arguments that unheated air or broths contained “vital force” necessary for spontaneous generation Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Air escapes from Microorganisms from open end of flask. air settle in bend. Years Hours/days 1 Broth sterilized— 2 Broth allowed 3 Broth stays sterile 4 Flask tilted so that 5 Bacteria multiply air escapes. to cool slowly— indefinitely. the sterile broth comes in broth. air enters. in contact with micro- organisms from air. 1.1. The Dispute Over Spontaneous Generation . Some scientists remained skeptical . Pasteur’s results not fully reproducible . English physicist John Tyndall finally explained conflicting data • Proved Pasteur correct • Sterilizing broths required different times • Some sterilized in 5 minutes • Others not despite 5 hours! • Realized hay infusions contained heat-resistant microbes • Contaminated labs using hay 1.1. The Dispute Over Spontaneous Generation . In same year (1876), German botanist Ferdinand Cohn discovered endospores • Heat-resistant form of bacteria . Following year, Robert Koch demonstrated anthrax caused by a spore-forming bacterium . Extreme heat resistance of endospores explains differences between Pasteur’s results and those of other investigators • Pasteur used broths made with sugar or yeast extract • Highlights importance of reproducing all conditions as closely as possible when conducting research Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. • Egyptians ferment • Pilgrims establish • Robert Hooke publishes his cereal grains to make Plymouth Colony: 1620 discovery of cells and sees beer: 1500 B.C. the first microorganism: 1665 • Harvard College, • Tutankhamen in first college in the • Edward Jenner introduces Egypt: 1300 B.C. U.S., founded: vaccination for smallpox: 1796 1636 Historical • Lewis and Clark explore Events the West: 1804–1806 . Some major • War of 1812 with England: 1812–1814 Milestones in Microbiology milestones in • First permanent English • American Revolution: • Ferdinand Magellan’s settlement in America, 1775–1783 ships circle the globe: Jamestown: 1607 1519–1522 • Antony van Leeuwenhoek microbiology in observes bacteria: 1676 • Girolamo Fracastoro suggests that invisible organisms may cause disease: 1546 • Napoleon defeated relation to other at Waterloo: 1815 • Louis Pasteur demonstrates that yeast can degrade sugar • J. Henle proposes to ethanol and carbon dioxide: 1857 the germ theory historical of disease: 1840 • Louis Pasteur refutes spontaneous events generation: 1861 • Mathias Schleiden and • Darwin publishes • John Snow demonstrates • U.S.–Mexican War: Theodor Schwann Origin of Species: the epidemic spread of 1846–1848 propose that all 1859 cholera through a organisms are composed contaminated water • American Civil • Ignaz Semmelweis demonstrates of cells: 1838–1839 supply: 1853–1854 War: 1861–1865 that childbed fever is a contagious disease transmitted by doctors • Louis Pasteur develops during childbirth: 1847–1850 pasteurization to destroy • Christian Gram describes organisms in wine: 1864 the Gram stain: 1884 • Elie Metchnikoff* discovers • Blacks given the • Robert Koch introduces phagocytic cells which right to vote in U.S.: 1870 pure culture techniques in engulf bacteria: 1884 • U.S. acquires the laboratory: 1881 • Koch states Koch’s Alaska from • Robert Koch* demonstrates postulates: 1884 Russia: 1867 that a bacterium causes anthrax: 1876 • Joseph Lister publishes the first work on antiseptic surgery: 1867 • Koch discovers the cause of tuberculosis: 1882 • Custer’s Last • Walter and Fanny Hesse Stand: 1876 introduce agar-agar as a • Dmitri Iwanowski discovers that solidifying gel for culture a filterable agent, a virus, causes media: 1882 tobacco-mosaic disease: 1892 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. • F. Peyton Rous discovers that a virus can cause cancer in chickens: 1911 • Frederick Griffith discovers • Women given the • Wright Brothers genetic transformation in right to vote in U.S.: 1919 make controlled bacteria: 1928 sustained flight: • Worldwide influenza • Alexander Fleming* discovers 1903 epidemic: 1918 first antibiotic, penicillin: 1929 Historical • Prohibition of alcoholic Events beverages repealed: 1933 . Some major Milestones in • World War II: Microbiology 1939–1945 • World War I: • Alcoholic beverages • First talking motion 1914–1918 prohibited in U.S.: 1920 picture made: 1928 milestones in • Paul Ehrlich develops • Beadle* and Tatum* show that genes • First woman elected the drug Salvarsan, direct the synthesis of proteins: 1941 the first chemotherapeutic to Congress: 1916 agent to treat syphilis: 1908 • Avery, MacLeod, and McCarty demonstrate that Griffith’s microbiology in transforming principle is DNA: 1944 • Milstein*, Kohler*, and Jeme* • Joshua Lederberg* and Edward develop monoclonal Tatum* demonstrate the transfer antibodies: 1975 of DNA between bacteria: 1944 • Jackie Robinson baseball relation to other • Theodor Diener demonstrates • Jacob* and Monod* playing days: 1947–1956 • Michael Bishop* and Harold fundamental differences between demonstrate how Varmus* discover that cancer- viroids and viruses: 1971 enzyme levels in cells causing genes are found in are regulated: 1961 historical normal tissues: 1976 • Carl Woese classifies all • Barbara McClintock* organisms discovers transposable events into three elements in maize: 1948 domains: 1977 • Voting age lowered • U.S. enters • Korean War: 1950–1953 from 21 to 18 in U.S.: 1971 Vietnam War: • Watson*, Crick*, Franklin, • Equal Rights Amendment 1959 (continued…) • Herbert Boyer and and Wilkins* determine the in U.S. gives women equal Stanley Cohen, structure of DNA: 1953 rights: 1971 clone DNA: 1973 • Arber*, Nathans*, and • D. Carlton Gajdusek* demonstrates the slow • A retrovirus causing a rare cancer Smith* discover the infectious nature of the disease kuru, later in humans is discovered: 1980 restriction enzyme: 1968 shown to be caused by a prion: 1957 • World Health Organization declares smallpox is eradicated: 1980 • The first new antibiotic in 35 years • Sony introduces the is approved by the Food and Drug Walkman: 1981 Administration: 2000 • Largest offshore • Cell phone becomes • The first complete nucleotide oil rig spill in U.S. commercially available: 1983 sequence of a bacterial history: 2010 • Attack on World chromosome is reported: 1995 Trade Center: 2001 • First product of genetic engineering introduced– human insulin: 1982 • Avian influenza • Luc Montagnier* and • The Food and Drug • Bioterrorism by anthrax • Barry Marshall* demonstrates considered a major Robert Gallo isolate Administration approves a spores in the U.S.: 2001 that a bacterium causes threat: 2005 and characterize the ulcers: 1982 genetically engineered human immunodeficiency • Stanley Prusiner* isolates a food for human virus (HIV): protein; a prion from a slow consumption: 1994 1983 disease infection: 1982 • Kary Mullis* invents the polymerase chain reaction: 1983 1.2. Microbiology: A Human Perspective . We could not survive without microorganisms . Numerous benefits . Examples include nitrogen fixation, oxygen