Human microbiota

Question 1

4 dominant phyla of gut microbiota (most to least)

Answer 1

1. firmicutes
2. bacteroides
3. proteobacteria
4. actinobacteria

Question 2

how is the gut microbiota influenced?

Answer 2

• diet
• disease state
• genetics
• develops at birth and changes with age

Question 3

4 dominant phyla of skin microbiota (most to least)

Answer 3

1. actinobacteria
2. firmicutes
3. proteobacteria
4. bacteroidetes

Question 4

how is skin microbiome influenced?

Answer 4

1. moistness/dryness
2. location on body

Question 5

what are the functions of the microbiota

Answer 5

1. breakdown of food: synthesis of AA or vit, breakdown of complex CHO or FA
2. immune system: changes disease state by detering pathogens (occupying niched and producing antimicrobials), can also decrease inflammatory response

Question 6

what bacteria dominate obese versus lean state

Answer 6

• firmicute:bacteroidetes ratio is larger in obese state -> more short chain FA are absorbed by host
• more methanogens -> accelerate FA production

Question 7

what bacteria tumorigenic

Answer 7

• b.fragilis
• produce BFT toxin