Pathways
When is substrate-level phosphorylation used?
By anaerobes or by aerobes that need rapid ATP production
Does gram pos or gram neg have multiple layers of peptidoglycan and therefore a very narrow periplasmic space?
Gram positive
Does bacteria or archaea "tumble" when their flagella rotates clockwise?
Bacteria
Is sulfa drug an example of competitive or noncompetitive inhibitor? Describe why?
Targets and binds to enzyme in a folate synthesis pathway and makes a product that cannot be passed down to make folate (which is needed in bacteria and humans)
Which of the 5 microbes are only pathogenic to humans?
Shigella flexneri and Haemophilus influenzae
What are the 3 types of fermentation?
Lactic acid fermentation
Alcohol fermentation
Mixed acid fermentation
What are the 2 functions of lipoteichoic and teichoic acids in gram positive organisms?
Contribute to overall negative charge of the cell
Serve as a physical barrier (toxins cant get into cell)
What is the most common layer in archaea cell wall morphology?
S-layer
What two components are essential for a holoenzyme to be fully active?
Cofactor and Apoenzyme
What are coccobacilli and which of the 5 microbes are coccobacilli?
Coccobaclli are extremely tiny rod shapes microbes (so tiny that they almost look coccus shaped)
Haemophilus Influenzae and Francisella tularensis
What is the name of the enzyme that recycled NADH to NAD+ in lactic acid fermentation
lactic acid dehydrogenase
Why is the periplasmic space larger in gram neg than in gram pos?
contains many enzymes
these enzymes help with nutrient uptake, peptidoglycan structure, energy conservation, etc.
What is the protein important for change in direction of flagella?
CheY protein
What do high and low Km indicate
Low Km = high affinity for substrates
High Km = low affinity for substrate
Which microbe has no flagella but can still move intracellularly? Why is it able to do this?
Shigella flexneri
Through polymerization of actin
What are the products of the TCA cycle?
4 CO2, 6 NADH, 2 FADH2, 2 ATP
Which basal body is more complex, gram positive or gram negative? What are the 4 rings of the complex basal body?
Gram neg = more complex
L ring, P ring, MS ring, C ring
What are the 3 steps of germination in bacteria? (Dont need to explain what they are, but you can :))
Activation - prepares spore for germination
Germination - environmental nutrients depleted, spore swells ruptures and absorbs spore coat, increased metabolic activity
Outgrowth - emergence of vegetative cell, everything returns to metabolically active state enzyme will regain activity and hydrolyze spore coat to release them into environment (start of sporulation cycle all over again)
How does an enzyme impact a spontaneous reaction?
enzymes have NOTHING TO DO with spontaneous reactions, they will run regardless when they have energy
Haemophilus Influenza is a fastidious grower that requires 2 growth factors, what are they?
Hemin and NAD/NADP
Explain how redox reaction works for electron carriers in oxidative phosphorylation
Each carrier is reduced when it gains electrons and re oxidized when it passes those electrons to the next carrier, creating a continuous flow.
What mechanism allows gram pos to be able to retain crystal violet but not gram negative? (hint: think about the ethanol stage of gram stain)
Gram pos has large pores that shrink at ethanol step that makes crystal violet remain in the pores
Gram neg outer membranes gets stripped during ethanol step and washes the crystal violet (so safranin retains instead of crystal violet)
Name 1 thing that makes archaea similar to bacteria and 1 that makes archaea similar to eukarya.
Bacteria:
Size is usually 0.5-5 um in diameter - Similar shapes (cocci, rods, etc) - Singular, circular chromosome - Lack a membrane bound nucleus or other membrane bound organelles - Low level compartmentalization
Eukarya:
DNA is complexed with histones - Homologues of DNA replication enzymes/transcription and translation - Subtle differences make it look more similar to eukarya than bacteria
Why is metabolic regulation important?
it is a critical part of cellular function that promotes efficient nutrition consumption, energy production and energy balance maintenance
What is the function of the Ti plasmid in Agrobacterium tumefaciens? (be specific).
Allows for pathogenicity
Plant wound secretes phenolics which the microbse senses and performs chemotaxis to go towards it, then forms T-pilus which allows the DNA of the bacteria to integrate with the plant