EBIO 3400 1st Edition Lecture 2Outline of Last Lecture I. Welcome to Microbiology/Introduction Outline of Current Lecture II. Brief History of Microbiology III. Food PreservationIV. Religion and mythologyV. MedicineVI. ScientistsVII. Microbial DiseasesVIII. Function in the biosphere Current LectureI. Beer and wine were ways to preserve fooda. Preservative= ethanol and lack of oxygen in sealed containerb. Wine making dates to about 5000 years ago in Persia (Iran)c. Also very ancient evidence in Egyptd. Egyptians used siphons to separate the wine from dead yeast cells after fermentation and aginge. When wine and beer cut off oxygen, only lets anaerobic microbes growII. Religion and Mythology a. Roman God of Mildew - holiday April 25th - sacrifice a red dogb. Diseases often blamed on the “Divine Wrath” of God III. Medicinea. Ancient peoples (e.g. China) realized that diseases could be transmitted via contaminated clothing and that humans could develop immunity to some diseases. b. Varro (Roman) proposed that tiny animals caused diseases. III. Robert Hooke (1635-1700): first to observe microscopic fungia. Credited for discovering cellsThese 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.i. Microscopes (1600s)a. 30x magnification and cork cells (latin for cellulae, meaning small rooms)IV. Anton Von Leeuwenhoek (1632-1723)a. Dutch draper used magnifying glasses to inspect clothb. Started grinding lenses to inspect cloth c. Fashioned a simple microscope by grinding grains of sandd. Items could be magnified 300 times or more to see large bacteria, protozoa, fungie. Single lens microscope with tiny lens fit in the hole i. The level of magnification achieved by Leeuwenhoek and could see tiny “animalcules” swimming in waterii. Spontaneous generation: Idea that things could come out of nothing and a lot of observations where there is nothing then there's something (e.g microbes or “critters”) – At this point in time, people still believed in this theoryiii. Microbes were thought to be the result of disease and not the causeiv. Theologians also had big problems with spontaneous generation V. Francesco Redi (Italian Priest, 1626-1697)a. Meat experiment - showed that only uncovered meat that was exposed to flies produced maggots....good example of an experiment (* Redi disproved spontaneous generation with this idea)b. Even with evidence like that, many still thought microbes were so simple that they didn't have to arise from other microbesc. Opposed primarily by the clergy because spontaneous generation went against their teachings VI. Louis Pasteur (1822-1895)a. French chemist and “father” of microbiology I. Pastuer and spontaneous generation and how to prove that simple microbes don’t arise via spontaneous generation ii. Hermetically sealed vessels didn’t give rise to microbes but some still argued that sealed vessels didn’t allow in the vital force  oxygen iii. Pasteur and the scientific method of experimentation 1. The Swan-neck flask- Have a reaction vessel; tube that opens to the atmosphere,dead air space so that anything coming into the small end and gases would diffuse into vessel but nothing bigger than gases could diffuse into the flask- Second step: only oxygen enters and nothing seems to appear- Once dust enters, microbes grow- Showed: Oxygen present then there is no spontaneous generation iv. Results 1. Pasteur put an end to the idea that there was some "vital force" in air, and he was the first to show that many bacteria and some fungi don't even need oxygen2. Anaerobes (literally (Greek) without air) : don’t have the enzymes to utilize oxygen; some can live with oxygen present but just ignore it while others may die immeditately3. Aerobes can use O2 in their metabolism4. Facultative anaerobes - aerobes that can also grow anaerobically 5. e.g. E. coli, brewers yeast and many more…II. Fermentationa. Pasteur explored fermentation of beets at the request of local famers resulting in lactic acid/acetic acid instead of ethanolb. Asked to help out at a winery some vats were “sick” - not making any alcohol by taking samples from the sick vats and from some healthy vatsc. In the healthy ones, he saw globulesand realized they were yeast (eukaryotic yeast cells) d. In the liquid from the “sick” wine, just saw bacteriae. Results: Pasteur reasoned that the yeasts must ferment the juice into alcohol,but that the bacteria fermented the juice into lactic acid insteadi. Ethanol Fermentation: yeast fermentation; used to make bread, wine and beerii. Lactic acid fermentation: many bacteria can do this- Spoiled wine: used to make yogurt, sauerkraut, and pickles via lactic acid bacteria. And the same as lactic acid fermentation in your muscles- Lactic acid is a really good preservative, very acidic environment is a good way to preserve food III. Pasteurizationa. Simply took heating the wine gently - below the point of boiling - to keep the microbes out (key: keep bacteria out of wine) b. Juice is now pasteurized and inoculated with the proper yeastc. Beer/Wine = 63oC for 30 min.d. Milk = 71oC for 15s or 141oC for 2se. Pasteurization ≠ Sterilizationf. Except… some things were hard to sterilize especially if they touched soil because when things have a lot of microorganisms its really hard to sterilize which leads to autoclave and pressure cookers IV. Autoclave and pressure cooker (1880)a. Sterilization achieved at 121oC under pressureb. Same as a big pressure cooker = heat + pressurec. Intro to endospores: containing cells (e.g. bacillus aerobes and Clostridiumanaerobes) i. Bacillus anthracis spores form in the middle of cells ii. Clostridium tetani spores at the end of cells Note: both nasty toxins/pathogens and the reasons why we have autoclavesiii. Archaea aren’t killed by autoclaves (e.g. Strain 121)- Iron reducing archaea discovered by Derek Lovely- Population doubled in 24 hour autoclave- An example of an extremophile V. Microbial diseases a. The significance of disease in warfare was first recognized by the British nurseFlorence Nightingale (1820–1910)- She founded the science of medical statistics- To show the deaths of soldiers due to various causes, she devised the “polar area chart”= chart of mortality data during the Crimean Warb. Bubonic Plague and