Lecture 13

Question 1

Is there a correlation between antibiotics and obesity?

Answer 1

Yes
-exposure to antibiotics in the first 6 months of life correlates with an increase in body mass
-exposure at later time windows did not show an increase in BMI

Question 2

Archaeal methanogens

Answer 2

Strict anaerobes reduce CO2 with H2 to produce methane (CH4)
-important for preventing the accumulation of acids and reaction of end products

Question 3

Why does the microbiome become more diverse in 1 year of life?

Answer 3

Babies can start eating actual food and not just breastmilk
-get microbes from food

Question 4

What are the main roles of the gut microbiome?

Answer 4

-first line of defense
-educator of our immune system
-metabolism

Question 5

Why can C. botulinum form endospores in honey?

Answer 5

Honey makes a hypertonic environment
-Hypertonic environment–> takes water out of cell
-causes bacteria to from endospores to survive

Question 6

Why can adults eat honey?

Answer 6

Adult microbiome is able to fight the germination of Clostridium botulinum spores

Question 7

What are bacteriocins

Answer 7

kill bacteria
-made by normal microbiota

Question 8

Why is mucus important in the intestine

Answer 8

Mucus protects the intestine from pathogens

Question 9

True or false: Thickness of mucus layer cannot be restored

Answer 9

False
-thickness of mucus layer can be restored by oral administration of LPS & peptidoglycan (PGN)

Question 10

How can lipopolysaccharides (LPS) and peptidoglycan (PGN) restore the thickness of mucus layer?

Answer 10

-LPS & PGN can be recognized by the toll like receptors (TLR)
-the TLR will trigger and activate an immune response from immune system by releasing inflammatory molecules which increase mucus

Question 11

True or false: bacteria and archaea in the gut decrease body fat

Answer 11

False
Bacteria with archaea have an increase in body fat
-methanogens allow for fermentation to occur b/c it makes anaerobic environment
-fermentation can produce an excess of short-chain fatty acids which is absorbed by host

Question 12

Metanogenesis

Answer 12

Prevent the accumulation of acids by removing hydrogen
-removing hydrogen allows for fermentation to occur

Question 13

What are the mechanisms of resistance

Answer 13

1. Produce enzymes that destroy drug
2. Alters binding targets of drugs
3. Prevents drug entry into target cell
4. Uses efflux pump to pump drug back out of cell