Introduction 2 of 2

Question 1

describe the three central metabolic pathways in microbes

Answer 1

1. glycolysis
2. TCA
3. PPP
   
   1. another way to break down glucose

Question 2

glycolysis

• ATP generated?
• How?

Answer 2

1. 2 Atp generated
2. by substrate phosphorylation, with OUT O2

Question 3

TCA cycle

1. whats the transition
2. which energy molecules are generated per 1 glucose in the TCA
3. energy used to drive formation of ATP
4. where?

Answer 3

1. end product of glycolysis=pyruvate, these 2 molecules are converted into acetyl-coa, which goes into the TCA cycle
2. TCA generates
   
   1. 2ATP, 6NADH, 2FADH2
3. Pronton motive force
   
   1. aka:oxidateive phosphorylation
   2. uses energy of proton gradient to generate ATP as the final electron accepter = Oxygen
4. located in the cytoplasmic membrane of prokaryotes
   
   1. NO MITOCHONDRIA

Question 4

theory that electron transport chain linked to ATP synthesis

Answer 4

chemiosmotic theory

Question 5

what are the two types of microbes with respect to O2 use?

Answer 5

1. aerobic
   
   1. terminal electron acceptor is O2
2. anerobic
   
   1. terminal electron acceptor in NOT O2
      
      1. Nitrate
      2. Sulfate

Question 6

describe the following categories

1. obligate aerobes
2. obligate anaerobes
3. facultative anaerobes

Answer 6

1. obligate aerobes
   
   1. use O2
2. obligate anaerobes
   
   1. O2 =toxic
   2. use fermentation or anaeobic respiration
3. facultative anaerobes
   
   1. prefer O2, but grow in absence

Question 7

describe the types of electron carriers in the ETC of prokaryotes

Answer 7

1. Flavoproteins (FAD)
2. Iron-sulfur proteins
3. Quinones
4. Cytochromes-contain heme

Question 8

fermenters

1. energy source
2. endproducts

Answer 8

1. reduce organic molecules
   
   1. involve substate level phosphorylation
2. endproducts
   
   1. lactic acid
      
      1. flavor and texture of chees, yogurt, pickles
      2. causes tooth decay
   2. ethanol
      
      1. reduction of acetylaldehyde
      2. wine, spirits, beer
   3. butyric acid
      
      1. produced by clostridium
      2. generate butanol and acetone
   4. propionic acid
      
      1. reduction of a byproduct of pyruvate
      2. propionibacterium produces this in the making of swiss cheese

Question 9

explain closed vs open system of bacterial growth

Answer 9

1. closed
   
   1. nutrient not renewed waste products are not removed
2. open
   
   1. nutrients added, waste products removed (maintain state of continuous growth)

Question 10

nutritional diversity leads to a host of categories explain the following:

1. heterotrophs
2. autotrophs
3. phototrophs
4. chemotrophs
5. photoautotrophs
6. chemolithoautotrophs
7. chemoorganoheterotrophs

Answer 10

1. heterotrophs
   
   1. use glucose as major carbon source
2. autotrophs
   
   1. fix carbon from enviornment
3. phototrophs
   
   1. harvest energy from sunlight
   2. photosynthesis
4. chemotrophs
   
   1. harvest energy from metabolizing chemical compounds
5. photoautotrophs
   
   1. energy=sun
   2. carbon=fixed
   3. called primary producers
   4. required by many organisms, including humans
6. chemolithoautotrophs
   
   1. energy=inorganic comounds for energy
   2. carbon=fixed
   3. live in hydrothermal vents, and other places absent of light
   4. called primary producer
7. chemoorganoheterotrophs
   
   1. energy=organic molecules
   2. carbon=organic molecules
   3. closest to humans

Question 11

Enviornment can be a categorizing opportunity for microbes, describe the following

1. neuttrophile
2. halophilepsychrophile
3. mesophile
4. thermophile
5. extreme thermophile
6. psychrotrophs

Answer 11

1. neutrophiles
   
   1. need a neutral pH
   2. unlike H. pylori, which grows in the stomach. using urease to break down ammonia, neutralizing the stomach acid.
2. halophiles
   
   1. can tolerate 10%salt and higher! (ocean=3.5%)
   2. use special pumps to draw in water
3. psychrophiles
   
   1. artic and antartic regions
4. mesophiles
   
   1. pathogens, soil bacteria.
   2. grow 25-45degC
   3. leprosy, requires certain temperature. which sections it off to the skin
5. thermophiles
   
   1. 45-70
   2. hotsprings, compost piles ,water heaters
6. extreme thermophiles
   
   1. 70-110
   2. deep sea vents, hydrothermal vents
7. psychrontrophs
   
   1. subcat of mesophiles, optimum 20-30
   2. spoilers in the refrigerator

Question 12

list the phase s and describe

Answer 12

1. lag phase
   
   1. bacteria gets into fresh medium
2. exponential phase (log phase)
   
   1. cells divide at constant rate
3. stationary phase
   
   1. cells have exhausted their supply
   2. not a major decline, because nutrition is obtained from dying cells
4. Death phase (decline)
   
   1. not as fast as log phase

Question 13

What are also known as primary producers?

Answer 13

chemolithoautotrophs

1. aka chemoautotrophs or chemolithotrophs
2. fix CO2 to form organic compounds
3. live in
   
   1. hydrothermal vents
   2. other places where sunlight is not available.

Question 14

microaerophile in the stomach

Answer 14

Helicobacter pylori

microaerophile

increase [O2] kills the bacteria

Question 15

helicobacter pylori is aclassified as

Answer 15

microaerophiles

lives in locations with little [O2]