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Define Microbiology Types of organisms studied in microbiology & their branches of microbiology Distinguish between prokaryotic & eukaryotic 2 metric scales used to measure bothbacteria & viruses (um & nm) 2 theories on how living things arise(spontaneous generation & bio- genesis) **Biogenesis - the idea that living things can only arise from other living things (of the same kind); Examples - mice from mice; dogs from dogs; bacteria from bacteria Developed methods for isolation**Which organism did Koch first identifyas an etiological agent of a disease?* Bacillus anthracis - causative agent forAnthrax Define Pathogen «Pathogen - Microorganism that can cause disease in the normal healthy individual «Parasite - microorganisms that live on or in the body of another organism *Host - other organism that the parasite is living on or in Microbes that normally live in or on a Define Normal Flora : human and do not cause disease What is taxonomy?+ Formal system Define Taxonomy for organizing, classifying and naming living things Originated by Carl Von Linne (CarolusLinneaus)- Know order of the taxa + Domain Bacteria - only prokaryotic organisms* Domain Archaea - only prokaryotic organisms* Domain Eukarya - only eukaryotic or- Which Domains or Kingdoms contain prokaryotic or eukaryotic organisms that we studied over the semester Concerned with:o Classification - orderly arrangement oforganisms into 8 taxa groupso Nomenclature - assigning nameso Identification - determining and recording traits of organisms for placement intotaxonomic schemes Know the order of taxa: Largest to smallestDid Green Popeye Come Over For Green Spinach?0 Domaino Kingdomo Phylumo Classo Ordero Familyo Genuso Species ganismss Kingdom - Monera - only prokaryotic organisms* Kingdoms o 6: Identification - results of tests andBergey's Manual (microbiology bible)(used to provide keys or charts) to identify optimal tempo 3: Isolation - isolate a single colony on apetri plate to obtain a pure culture (streakplate, pour plate, spread plate)o 4: Inspection - observe the cultures formacroscopic growth of the bacteria, observe microscopically for results of stains(used for unknown #1; gram stain, endospore stain, acid/fast stain)o 5: Information gathering - testing ofcultures for biochemical and enzymecharacteristics and additionally with drugsensitivity, immunologic reactions, andgenetic makeup. (unknown #2) the genus and species of the microorganism Define Pure Culture Define Mixed Culture Physical types of media (solid, liquid, semisolid) One microbe growing on or in the culture medium More than one microbe growing in sample or culture medium Liquid media -* Consistency like water; usually a broth(used in unknown #2)» Used in test tubes Contains no gelling agent = no agar Examples - nutrient broth, nitrate brothSemisolid media -+ Used only for motility teste Has a soft consistency Used in test tubes Contains a small amount of agar(.3%-.5%)* Examples - motility agarSolid media -Solid - provides a firm surface for colony formations Used in test tube or petri plates Contains larger amount of agar(1%-5%)= Examples - nutrient sugar, TSA Difference between simple vs. differential stain Primary stain vs. counter stain What stain Hans Christian Gram developed **Simple Stain -o Uses a single dye to stain bacterial cello Helps to distinguish shape, arrangement, and size of cellso Examples - methylene blue, crystal violet**Differential Stain -o Uses 2 different colored dyes: primaryand counter staino Used to distinguish different cell typesor cell partso Examples - gram; acid fast; endospore Primary stain - goes on microbe first Counter stain - goes on microbe second Gram stain is a 130 year old method named for its developer Hans Christian Gram. The gram stain is the basis of several important bacteriological topics, including bacterial taxonomy, cell wall structure, identification, and drug therapy. Who developed Petri plate Agar was first described for use in microbiology in 1882 by the German microbiologist Walther Hesse, an assistant working in Robert Koch's laboratory, on the suggestion of his wife Fannie Hesse.[7][8] Agar quickly supplanted gelatin as the base of microbiological media, due to its higher melting temperature, allowing microbes to be grown at higher temperatures without the media liquefying. A Petri dish (sometimes spelled "Petrie dish" and alternatively known as a Petri plate or cell-culture dish), named after the German bacteriologist Julius Richard Petri, is a shallow cylindrical glass or plastic lidded dish that biologists use to culture cells - such as bacteria - or small mosses Motile vs Non Motile How prokaryotic flagella operates (rotates 360) = run & tumble vs. eukaryotic flagella round cellso Streptococcus - chain of round cellso Staphylococcus - irregular cluster ofround cellso Tetrad - packet of 4 round cellso Sarcina - cube of 8 or 16 round cellsBacillus arrangements:o Single - one oblong cello Diplobacillus - a pair of oblong cellso Streptobacillus - chain of oblong cellso Palisade - match sticks or picket fenceor oblong cells * Motile - bacteria will flip, rotate and gostraight» Non Motile - will only exhibit 'brownianmovement' (jiggles about in one placebut makes no progress) Prokaryotico Flagella rotates 360 degrees; includesa series of runs & tumbleso Straight run = flagella spins counterclockwiseo Tumble = flagella spins clockwiseEukaryotico Flagella whips back and forth for movement (ex. Sperm) Fimbriae - a solid protein; fine hair-like bristles emerging from cell surface o Function - used for attachment to environment (ecoli use to attach to inside of bladder) Fimbrae & Pili - Describe & Function Composition of the cell envelope Function of the glycocalyx & that not all bacteria have one Pilis (pili - plural) - hollow structure; rigid protein tube structureo Found only in gram negative species o Function - used for attachment to another bacteria to exchange DNA during CONJUGATION. * Cell wall and cell membrane = cell envelope Glycocalyx (2 types) - coating of molecules external to the cell wall, made of sugars and/or proteinso « Function - to determine shape and prevent lysis due to changing osmotic pressures « Composed of unique organic molecule - peptidoglycan. (a few are composed of something else) Understand that all bacteria have a cell wall except Mycoplasma. « Mycoplasma is the only bacteria without a cell wall! * No cell wall = mycoplasma * Cell wall is stabilized by sterols « Medically important bacteria - slide 18 4.3 « Pleomorphic = atypical shape Understand that peptidoglycan is the major molecule in the bacteria cell wall. + Peptidoglycan is the major molecule in the bacteria cell wall. Peptidoglycan is the major molecule * Peptidoglycan is the major in the bacterial cell wall molecule inthe bacteria cell wall. Gram positive - thick Know the difference between G+ peptidoglycan layer; teichoic acid & Gcell wall w/respect to present; no outer membrane; thickness of peptidoglycan, positive=purpleGram negative - presence of teichoic acid, and thin peptidoglycan layer; teichoic presence of an outer membrane acid not present; has outer membrane; negative=pink Composition of the cell membrane & its primary function 10/62 Composition of the cell membranes and its many functions. + All bacteria have a cell membrane *« Composed of phospholipid bilayer embedded with proteins * Functions: o MAIN - selectively allows passage of molecules into and out of cell o Serves as DNA anchor during binary fission engineering - readily manipulated and transferred from cell to cellVery important to bacterial resistance RIBOSOMES: Made of 60% ribosomal RNA and 40%proteine Consist of 2 subunits: large and small* Prokaryotic differ from Fisnefion of ribasones eukaryotic ribosomes in size and number of proteinss Site of protein synthesis» Found in all cells!o (smaller) Prokaryotic cells: 70S =50S+30So (larger) Eukaryotic cells: 80S =60S+40S « Inert, resting cells produced by someG+ genera - clostridium & Function of endospores bacillus(pathogens that cause disease) Have a 2 phase life cycle:o Vegetative cell - metabolically o Not a means of reproductions Germination - return to activeand growingo Endospore - when exposed to adverse environmental conditions; capableof high resistance and very long termsurvivalDehydrated, metabolically inactive (hydrate to activate)Thick coatLongevity verges on immortality, 250 million yearsResistance to ordinary cleaning methods & boilingPressurized steam @ 120C for 20-30 mins will destroyOnly a few species can form endospores « Sporulation - formation of endospores o Hardiest of all life forms o Withstands extremes in heat, drying, freezing, radiation, and chemicals 
