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What are the groups of microbe organisms:
- Bacteria
- Fungi (yeasts/molds)
- Protozoa
- Algaea
- Viruses
- Helminths
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Nomenclature
Established by Carolus Linnaeus
Two names: Genus + Speccific eptithet(species--always lowercased)
ex: Staphylococcus aureus OR Staphylococcus aureus
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Bacteria (group)
--> pro/eukaryotes?
--> Shapes?
--> cell walls?
--> Reproduction?
--> how do they eat?
- Unicellular prokaryotes (means DNA is NOT in a nuclear membrane)
- Either Baccillus (rodlike), coccus (sphere), spiral (corkscrewed)
- Cell walls: Peptidoglycan (carb + prootein complex)
- Reproduce by binary fission-divide into two equal cells
- Some can photosynthesize, while others get food inorganically.
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Archaea (group)
-->pro/eukaryotic?
--peptidoglycan?
--> what are three groups?
--> pathogenic?
- Prokaryotic-No peptidoglycan
- 3 groups: methanogens, extreme halophilles (salt lovers) and extreme thermophiles (hotsprings)
- **NOT pathogenic
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Fungi (group)
--> pro/euk?
--> cell walls?
--> uni/multi cell?
--> 2 types and characteristics?
- Eukayotes
- Uni or multicellular
- cell walls: chitin
- yeast: unicellullar
- mold: reproduce either sexually or asexually
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Protozoa:
--> Pro/euk?
--> uni/multi cell?
--> how do they move?
--> how do they survive?
- Unicelluar
- Eukaryotic
- Move with: flagella, pseudopods, cillia
- environments: free living or parasitic
- Some can photosynthesize (euglena)
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Algae:
--> pro/euk?
-->Uni/multi cell
--> cell wall:
--> most common where?
--> how do they help envir?
--examples
- Photosyn. Eukaryotes
- usually unicelluar
- cell wall: cellulose (carb)
- Most found: in fresh water, salt water, and soil
ex: spyrogyra, diatoms,
**Produce O2 and carbs for other organisms.
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Viruses:
--> Nucleus memb?
--> euk/pro?
--> where do they reproduce?
- Accellular o.0
- Either only have DNA or RNA in a lipid membrane (neither euk/pro)
- Reproduce in hosts
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Helminths:
multicellular animal parasites
Includes: flat and round worms
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Three Domains & 4 kingdoms:
- Bacteria
- Archaea
- Eukarya
- 1.Animalia-Helminths
- 2. Protista: protozoa & algae
- 3. Fungi
- 4. Plants (no microbes)
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Gram Positive:
Bacteria that retain the dye after decolorizing alcohol
-->thicker peptidoglycan cell wall,dye and iodine enter and form CV-I complex-larger molecule than crystal violet molecules that entered, so it cannot leave==> so alcohol does not wash out the dye.
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Gram Negative:
Bacteria that LOSE the dark violet color after decolorization
( safranin must be added to stain these pink to counter the original purple stain so called a "counterstain")
- --> contain layer of lipopolysaccharide as part of cell wall (alcohol wash disrupts this outer layer, and the "CV-I" complex is washed out through the thin layer of petidoglycan)
- -->must be redyed with safranin. :)
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Diphtheria:
Upper respiratory Bacterial infection caused by Corynebacterium diphtheriae
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Diphtheria Symptoms:
Begins with sore throat and fever, neck swells
- -often affects throat(pharynx) and larynx (voicebox)
- -creates a pseudomembrane of fibrin, dead tissue and bacterial cells that clogs throat/air passage
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Diphtheria Microbe:
- Microbe: Corynbacterum diphteriae
- --> gram positive
- --> non-endospore-forming rod
- --> cell arranged: palisades
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Diphtheria Vaccines:
- DTap Vaccine: for children, "D" stands for Diphtheria toxoid (inactivated toxin) that allows body to make antibodies against diphtheria.
- --> "Toxoid vaccine" based on inactivated exotoxin
Tdap booster: teens and adults (combined with tetanus shots)
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Diphtheria Transmission:
Droplet transmission; resistant to drying (coughing, sneezing, talking)-also skin contact with humans
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Exotoxin:
- Toxic proteins secreted by bacteria;
- produces strains that cause disease.
- Related bacteria are present on skin and are not pathogenic.
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Mortality and complications from Diphtheria
- Suffocation/death-children mostly
- Heart/peripheral nerve damage
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Diphtheria Diagnostic methods & treatments
Diagnose: throat swab culture; PCR (polymerase chain reaction-method to make many DNA copies) to grown and study
treatments: Antibiotics & antitoxins (penicillin/erythromycin)
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Pertussis:
Whooping cough; damages cilliated cells in respiratory system
- -paralyzes the cilliated cells
- -cause inflammation
- -impairs immune response
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Pertussis Microbe
- caused by Bacterium "Bordetella pertussis"' obligatory aerobic
- gram negative
- coccobacillus
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Pertussis Mode of Transportation
Transportation: respiratory droplets (coughing/sneezing)
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The stages of Pertussis:
First Stage (catarrhal stage) resembles common cold- coughing, sneezing, low fever (100 deg F)
Second Stage (Paroxysmal stage): severe prolonged coughing fits, may make "whoop" sounds; difficult to cough up phlegm when cilliated cells are destroyed.
Third stage: coughing eventually become less frequent and less severe (convalescence)
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Pertussis Complications:
- -break ribs
- -brain damage/death in babies by coughing
- -pneumonia
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Pertussis Diagnosis
Diagnosis: culturing bacteria (swab and identify)
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Pertussis Treatments:
-Herd immunity
- 1. First stage: give antibiotics
- 2. second stage:
- 3. DTaP: subunit of pertussis (begins at 2 months old, given 3 shots total)
- 4. Boosters for teens
- 5. Tdap: adults
- 5. Vaccine rate: 93% herd immunity (reduced chance of infection of vulnerable individuals if a certain high percentage of individuals in the populations are vaccinated or immune.)
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Prokaryotes: distinguishing characteristics
- 1. Dna has no enclosed membrane
- 2. lack membrane enclosed organelles
- 3. cell walls are complex polysacharide peptidoglycan
- 4. Divide with binary fission
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Eukaryotes
- 1.Has nucleus to sep dna from cytoplasm
- 2. have many membrane enclosed organeles
- 3. chemically simple cell walls.
- 4. cell division: mitosis.
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Prokaryote vs Eukaryote Structures (image)
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Plasma Membranes: Prokaryote vs. Eukaryote
BOTH have it!
similarities: phospholipid bilayer with proteins, separates cells from outside
Differences: not applicable
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Cell Wall: Prokaryote vs. Eukaryote
- Prokaryote:
- Bacteria has peptidoglycan;
- Archea-Pseudopeptidoglycan
- Eukayotes:
- Fungi: Chitin
- Plants&Algae: Cellulose
Similarities: structural support, resists bursting, made of polysaccharides
Differences: Chemical composition; some eukaryote do lack cell walls
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Chromosome (genetic material)
Prokaryotes: Circular, only one chromosome in "nucleoid" region
Eukaryotes: Linear, variable number of chromosomes/associated with histone protiens
- Similarities: Made of DNA
- Differences: Different (?) and organization
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Nucleus: Prokaryote vs. Eukaryote
- Prokaryote: NONE
- Eukaryote: Present :D
**THIS IS THE DIFFERENCE**
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Flagellum: Prokaryote vs. Eukaryote
Prokaryote: Rotational motion in Bacteria
Eukaryote: whiplike in animals
- Similarities: Locomotion
- Differences: Diff type of motion & chem compositon
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Ribosomes: Prokaryote vs. Eukaryote
- Prokaryote: Present
- Eukaryote: Present, some associated with RER
- Similarities: Protein synthesis
- Diffs: prok have smaller ribosomes
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Membrane Bound Organelles: Prokaryote vs. Eukaryote
- Prokaryote: NOT PRESENT,
- Eukaryote: Rough ER, Mitochondria, Golgi Body, lysosomes, chloroplast
- Similarities:None.
- Differences: Prok lack; euk often have several membrane bound organelles
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Capsule (pg 70)
- Firmly attached to cell wall (made of glycolax-gelatinous polymer)
- -protect pathogenic bacteria from phagocytosis :(
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Slime Layer
- another type of glycolax;
- Loose, thinner, flexible attached to cell
- -Helps bacteria attach to surface
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Endospores (70. 95-97)
-purpose and characteristics
-endospore components
-locations
-example:
Resting structures formed by some bacteria, allows for survival during adverse environmental conditions (dry conditions)
- Characteristics:
- very little water
- resistant to heat, uv rays and disinfectants
- Components: cytoplasm, plasma membrane, ribosomes, peptidoglycan, spore coat (protein) and dipicolinic acid
Locations: terminal(very end), central and subterminal (almost end)
ex: clostridium tetani
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Sporulation:
(germination?)
- 1. DNA is replicated
- 2. Endospore forms when plasma membrane, peptidoglycan layer, and spore coat surround DNA
- 3. endopsore is related as vegative cell disintegrates
"germination": return of endospore to it's vegetative state
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Practice questions:
1. How do you get rid of endospores?
2. How is an endospore diff from a begetative cell?
3. can bacteria reproduce by using endospores?
4. what would happen if an endospore got into bloodstream of a patient?
5. Do we need to strilize our food to get rid of endospores?
- 1. calibrate by increasing or decreasing temp
- 4. spermination
- 5. Pasteurization, canned food: get rid of botchulism endospores
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EPS: extracellular polymeric substance
a glycocalyx that helps cells in biofilm attach to target environment and allow bacteria to survive
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Endoplasmic Reticulum (ER) & RER
- Nuclear envelop attached to Endoplasmic Reticulum (ER)
- --surface for chem reactions and transport network.
- --RER: protein synthesis/transport
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Golgi complex:
flattened sacs (cisterns); fuctions in membrane formation & protein secretions
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Lysosomes:
form by golgi complexes; store digestive enzymes
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vacuoles:
memb enclosed cavities; give rigidity to plant cells
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Mitochondria
- primary ATP site production;
- contain 70S ribosomes & dna.-multiply by binary fission
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Peptidoglycan:
polymer consisting of NAG (N-acetylglucosamine) & NAM (N-acetylmuramic acid) and short amino acid chains; penicillin interferes with this wall
--in gram positive cell walls; crystal violet combines with peptidoglycan but decolorizer removed the lipid outer memb of gram negative bacteria and washes out crystal violet.
Gram neg walls: thin peptidoglycan layer and a lipopolysaccharide-lipoprotien-phospholipid layer (-.-)
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Gram Negative cells (chemical structure)
- -MUCH more complex-Thin layer of peptidoglycan
- -LPS (lipopolysaccaride)
- -Porins
- -Periplasms with chemoreceptors: gel like fluid between outer membrane and the plasma membrane
- -NO teichoic acids;
- OUTER membrane: contains LPS, lipoprotiens and phospholipids
- --gives wall strong neg charge
- --provides barrier to antibiotics, digestive enzymes,and dyes
- --Porins: channels allow nucleotides, amino acids
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Gram Positive Cells (chemical structure)
- -Many layers of peptidoglycan
- -Thick ridgid structure
- -teichoic acids: alcohols (glycerol) and phosphate; gives wall antigenic specificity to allow group into "gram pos" cells
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How do Gram stains work?
-Crystal violet purpose
-Iodine purpose
-Alcohol effect to both walls
- ADD what dye after, what kind of dye is this?
-Based on differences between cell wall structure (type of differential stain)
Crystal violet (primary) stain both cells
Iodine: forms large crystals with dye that are TOO large to escape through wall
Alcohol: dehydrates peptidoglycan of gram positive cells and make it more impermeable to crytal violet-iodine. BUT on gram negative: the alcohol dissolves the outer membrane of gram negative cells and even leaves small holes in the thin peptidoglycan layer SO THAT crystal-violet-iodiine leaves!
This is why safranin must be added to stain gram negative cells (turn them red)--contrasting stain
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Tetra peptide Side Chain
- Composed of NAG & NAM
- -NAG: N-acetylglucosamine
- -NAM: N-Acetylmuramic acid
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Bacterial shapes:
coccus, spiral, star, pleiomorphic
- Rod/bacillus: cylinders
- coccus: sphere
- spiral: spirillium (w/flagella) or spirochete (axial filaments-rotate)
- star
- pleiomorphic: many shapes (corynebacterium diphtheriae-cause diphtheria)
- coccobacilillus
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Bacterial Cell ARRANGEMENTS:
strepto
tetrad
staphylo
palisade
diplococcus
- the ways cell stick together:
- 1. strepto: chains of cells
- 2. tetrad: group of 4 cells
- 3. stahylo: grape like clusters
- 4. palisade: picket fence
- 5. diplococcus: two circle oo
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Cytoplasmic bodies
Nutrient storage
metachromatic granules
magnetosomes
- a. nutrient storage:
- --> ex: polysaccharides granules for store starch
- --> lipid inclusions store lipids
- -->sulfur bacteria store sulfur as energy source
- b. metachromatic granules with phosphate (turn red): inorganic phosphate storage
- --> used to diagnose Corynebacterium diphtheriae
c. magnetosomes: contains iron compounds, use to orignet to magnetic fields
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Pili and Fimbriae
Pili: straight, hairlike, gene transfering
Fimbria: straight hairlike for attachment ex: neisseria gonorrheae
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Flagellum
-Monotrichous
-Peritrichous
-Amphitichous
-flagellin
Parts of flagellum?
long appendages that propel bacteria
monotrichous: single flagellum at one pole
Peritrichous: flagella distributed over entire cell
amphitrichous: flagella at both poles of the cell
flagellin: protein that is the main component of the filament
- Main parts of flagella:
- Basal Body-anchored the whole flagellum to the cell wall and PM
- Hook: rotates
- filaments
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Biofilms
-defn
-found?
-advantages?
-Community of bacteria; form at liquid-solid interfaces; slime layer ( extracellular polymeric substance-EPS:helps bacteria attach to surfaces)
-protected from antibodies and antibiotics; wbc's create inflammation
-found: teeth, rock in a pond, pet's waterdish
- advantages of biofilm:
- prevents dehydration
- share nutrients
- protection from host immune system (antibodies or wbc phagocytosis)
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Biofilms Review Questions:
1. Explain how a biofillm protects bacteria from antibiotics
2. Best way to get rid of biofilms
- 1. Protective barrier
- 2. Physically remove them
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Quorum Sensing:
- Bacteria organize into communities using chemical communication to make biofilms,
- disruption will allow for prevetnion
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Dehydration synthesis:
removes water; convalently link molecules (CONDENSATION)
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Hydrolysis:
ADD water to break apart two covalently linked molecules
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Four groups of biological molecules?
- 1. carbs
- 2. Lipids
- 3. Proteins
- 4. Nucleic acids
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Carbohydrates
Functions: energy source/storage, carbon source and part of cell structure
- -Composed of C,H,O
- -Hydrophillic (waterloving)
-Sacchardies
- Monosaccharides: hexose, pentose
- Disaccharides: lactose (glucose+galactose) and sucrose/canesugar (glucose and fructose)
- Polysaccharides: cellulose (plant/algae cell walls), starch (energy storage), petidoglycan (bacterial cell walls)
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Lipids functions and structure::
1. triglycerides
2. fatty acids
3. saturated vs. unsaturated
4. phosoplipids
5. sterols
Fn: energy storage, cell memb components
Structure: C,O,H and sometimes P & S
-HydroPHOBIC (dont dissolve)
Triglycerides: 3 carbon glycerol + 3 Hydroxyl (OH) groups
Fatty acids: C-H chain + carboxyl group at the end
saturated fatty acids: only single bonds b/w carbons (fats: butter and shortening)
Unsaturated: double or triple bonds give it a kink (oils)
Phosoplipids: two fatty acids + glycerol + phosphate group + "R" group (hydrophillic)
Sterols: 4 connected carbon rings, not composed of fatty acids, hydrophoics
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PROTIENS
FN: cell structure (flagella, cytoskeleton, enzymes, chem signals)
exotoxins: transporters in cell membranes (botulism toxin)
- Amino acid: building block of proteins:
- --> amino group (NH2)
- --> carboxyl group (COOH)
- --> R group connected to central carbon
Peptide bonds: created by dehydration synt. b/w 2 amino acides; spacial type of covalent bond
Peptide: short chain of amino acids; Polypeptides (structure: primary, secondary, tertiary and quaternary sturcture)
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Nucleic Acids:
DNA: genetic code/template fro protein making
RNA: helps make proteins
- Nucleodtide has 3 parts:
- 1. 5C sugar (ribose/deoxyribose)
- 2. Phosphate backbone(PO42-)
- 3. Nitrogenous base (can form H bonds)
- DNA bases: Adenine, guanine, cytosine, and thymine
- RNA bases: uracil instead of thyamine
ATP (adenosine triphosphate): function as energy "currency"; stores and provides chemical energy, made out of ribose, adenine and 3 phosphates linked together.
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Growth Condition Factors of Microbes
- A. Temperature
- B. Liquid water-with vapor
- C. pH: most enjoy neutrality; peptones used as buffer salts in mediums
- D. Nutrients: Carbon (auto/hetero) or Electrons (Chemotrophs)
- E. Oxygen levels or Lack of it (need a balance)
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Temperature Requirements:
Optimal, Minimal, Maximal
- Minimum: lowest temp at which species will grow.
- Optimum: best temperature for growth.
- Max: highest temp at which growth is possible.
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Psychrophile
- Likes 0-20 deg C
- 15= optimum
- -cold-loving microbes
- -found in oceans/polar regions.
- -unlikely to spoil food
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Psychrotroph
Grow slowly at low temps but optimum from 20-30
-Responsible for food spoilage; grow well at refrigerator temps though cold temps slow down reproductive rates.
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Mesophile
Optimum: 20-40 deg temps "middle" (room)
- -moderate-temperature loving microbes
- -live in terrestrial/aquatic areas, plants & animals
- - may cause disease: likes body temp of host
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Thermophile
Optimum: 40 degs Celsius and higher
- - heat-loving microbes
- -endospores: fromed by these bacteria; may survive heat treatments given to canned foods.
- -found: hot spring run offs; compost piles
- ex: Thermus aquaticus: yellowstone
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Hyperthermophile
Extrememophiles!
- Optimum: Higher than 80 deg C (boiling/acidic water)
- Domain: Archaea; different from bacteria (don't denature)
ex: Sulfolobus (yellowstone)
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Acidophiles vs. Alkaliphile
- Bacteria tolerant to acidity
- -Molds: pH 5; Lactobacillus bacteria
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Halophiles:
-->importance of osmotic pressure?
--> extreme, obligate and faculative
Salt-loving
--> osmotic pressure: loss of water causes plasmolysis (shrinkage); imp b/c inhibits cell growth and preserve food
Extreme halophiles/obligate(require) vs. Faculatative halophiles (don't require but won't hurt either)
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Chemical requirements:
Carbon
Oxygen: obligate aerobes, facultative anaerobes, obligate anaerobes
Nitrogen :Dna & RNA synthesis; nitrogen fixation by cyanobacteria (anabaena)
Sulfur: synthesize vitamins-biotin, thiamine
Phosphorous: ATP synthesis; nucleic acids and phosopholids of cell membranes
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Aerobes
a. Obligate
b. Microaerophillic
Use Oxygen; extract more energy from nutrients than anaerobes.
- a.Obligate/Strict Aerobes: MUST have it.
- --> disadvantaged b/c not much oxygen in water
b. Microaerophilic: uses small amounts
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Anaerobes:
a. Obligate
b. Aerotolerant
- a. Obligate: bacteria that are unable to use molecular oxygen for energy yielding reactions; require oxygen to live
- ex: clostridium (known for botulism & tetanus)
b. Aerotolerant: cant use oxygen for growth, but can tolerate it.
-ferment carbs to lactic acid. ex: lactobacillus makes pickles/cheese
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Anaerobe Jar
Forms water to remove oxygen
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Facultative Anaerobes
Bacteria that have developed or retained the ability to continue growing WITHOUT oxygen.
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Biofilms
-quorum sensing
-form where?
-preventions?
microbe communities; in slime (matrix of polysaccharides with DNA/proteins)
- -quorum sensing: allows bacteria to coordinate activity and group together
- ex: plaque, pond rocks
- -work cooperatively on same task
- -primitive circulatory systems: incoming nutrients and waste channels
- -1000x More resistant to microbicides; form on medical devices
- -protected by antibodies, WBC phagocytosis and antibiotics
Preventions: block quorum sensing, incorporate antimicrobial into possible biofilm surfaces; must physically remove them
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Binary Fission Diagram
Shows binary fission (bacteria) or mitosis (fungi) reproduction
- a. Lag Phase: Preping/intense activity; no increase
- b. Log Phase: exponential increase
- c. Stationary Phase: equilibrium (deaths balance new cell production)
- d. Death phase: decreasing population
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Nutrional names for organisms
Phototrophs: use lights a primary energy souce
chemotrophs: depend on oxidation-reduction reactions of inorganic/inorganic compounds for energy.
- Autotrophs (self feeders: use CO2)
- --> litotrophs(rock eaters)
- Heterotrophs (use organic carbon source)
- --> organotrophs
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