MICR J210 1st Edition Lecture 1Outline of Last Lecture I. NoneOutline of Current Lecture II. The Early Years of MicrobiologyA. Antoni LeeuwenhoekB. Carolus LinnaeusIII. The Golden Age of MicrobiologyA. FracescoRediB. Louis PasteurC. The Scientific MethodD. IgnazSemmelweissE. Robert KochIV. The Modern Age of MicrobiologyA. Serology V. Four Categories of Human PathogensA. Bacteria B. FungiC. ProtozoaD. VirusesCurrent LectureIntroduction- Nosocomial Infections: hospital acquired infectionso Best prevented by hand washing- Pathogenesis: beginning of a pathogeno Virulence factors are traits of the microbe that determine what becomes infected in its host- Microbial antagonism: preventing diseaseo Immune system, drugs, sterilization- Enzymes: catalyst to get a reaction underway (Virulence factors act as enzymes)- Aseptic technique-DO NOT CONTAMINATEo Aseptic and sterile are not the same thingsThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.The Early Years of Microbiology- Antoni von Leeuwenhoek (17th century)o Made simple microscopes and examined water dropletso Called them “animalcules”- CarolusLinnaeso Developed the taxonomic system in order to name these microorganismso Categorized into six different groups Fungi- Eukaryotic (contain nucleus)- Obtain food from other organism (like an animal)- Contain a cell wall (like a plant)- Include both molds and yeastso Mold: multicellular Sexual and asexual sporeso Yeast: unicellular Asexual through budding (daughter cell grows off of the mother cell) Has some sexual spores Protozoa- Eukaryotic - Unicellular- Contain pseudopods, cilia, and flagella- Can also be non-motile - Mostly sexual and live in watery environments Algae- Photosynthetic eukaryotes- Both uni- and multicellular- Have simple reproductive structures Bacteria- Prokaryotes- Asexual- Cell wall is made of peptidoglycan- Live in mild environments- Can be both beneficial and harmful Archaea- Prokaryotes- Asexual- Cell wall is different from bacteria and is made from other chemicals- Live in extreme environments- Not known to ever cause disease Small multicellular animals (such as parasitic worms)- Varies with speciesThe Golden Age of Microbiology-(The most important decisions were made in this time period)- Scientists searched for answers to four questionso Is spontaneous generation of microbial life possible? This was first suggested by Aristotle and has been disproveno What causes fermentation? During these times, drinking water was highly notorious for causing infections, so fermentation was used to eliminate pathogenso What causes disease?o How can we prevent infection and disease?- Francesco Redi’s Experimentso Three jars of meat: uncovered meat grew larvae, sealed jar did not grow larvae,and gauze covered jar with meat did not grow larvaeo As a result, people began doubting spontaneous generation The larvae did not spontaneously generate in the sealed and gauze covered jars- Louis Pasteuro Frenchmen from Pariso Created swan necked flask that allowed air to freely flow to a boiled bacteria-free infusion He prevented particulate matter from reaching the infusion After months, the infusion remained sterile o His experiments helped lead to the development of the scientific method Observe Ask a question Generate a hypothesis Test through experiments Compare results with hypothesis- Disprove or prove hypothesis- Accepted hypothesis leads to theory/law- Rejected hypothesis will require modification and further experimentation- When experimenting—only use one variable and make sure that the hypothesis and results can be reproducible o Pasteur and Fermentation Spoiled wine threatened livelihood of vintners Many believed that air caused fermentation (which erroneously supported spontaneous generation)- Pasteur however, proved that fermentation was caused by yeast Yeast ferments grape juice into alcohol- First the juice is heated to kill all pathogens, then inoculated with yeast and sealed. The Yeast reproduce and alcohol is producedThe Golden Age of Microbiology- What causes disease?o IgnazSemmelweiss noticed that “cadaverous material” from doctor’s hands working in the cadaver lab was infecting mothers in labor with childbed fever He advocated for the washing of hands in bleach and the mortality rate dropped by 90%o Louis Pasteur developed a germ theory of diseaseo Robert Koch studied causative agents of a disease Anthrax was infecting cattle and killing livestock-he was able to isolate and examine colonies of microorganisms Koch’s Postulates- Suspected causative agent must be found in every case of the disease and be absent from healthy hosts- Agent must be isolated and grown outside the host- When agent in introduced into a healthy, susceptible host, the host must get the disease- Same agent must be found in the diseased experimental host(side notes: there are more microbial cells than human cells, in order to fight disease with drugs one has to be able to distinguish between the harmless microbes and the few pathogenic ones that can cause big problems)- Extra Reading assigned by professoro Semmelweis and hand washing Bleach eliminated “cadaver particles” Killed Streptococcus which caused puerperal fever or “childbed fever”o Lister’s antiseptic technique Sprayed wounds and instruments with carbolic acid and reduced mortality by 2/3o Nightingale and Nursing Set standards of cleanliness and other antiseptic techniques into nursing 200 scrubbing brushes to clean the hospital ward, ordered clean patient clothes, and sanitary food Founded the Nightingale School of Nursingo Snow and Epidemiology Studied cholera epidemic and traced source to water supply Highlighted critical need for proper water supply and sewage treatment- Infections control- Epidemiology (the study of the occurrence, distribution, and spread of disease)o Jenner’s vaccine Infected boy with cowpoxsurvived and then infected him with smallpox survived Began the field of immunology Developed vaccines against smallpox, fowl cholera, anthrax, and rabiesThe Modern Age of Microbiology- Serology: Study of blood serum- Immunology: Study of body’s response against pathogens- Chemotherapy: drugs used to prevent, protect, and kill pathogens)Four