Lecture 4

Question 1

Joshua Lederberg

Answer 1

• discovered recombination
• received doctorate at yale

Question 2

microbiome

Answer 2

• 10x bacteria to human cells
• produce vitamins, enzymes, metabolism, immune system
• compete with other microbes

Question 3

Microbiome biochemical reactions

Answer 3

• deamination of amino acids -> ammonia
• vitamin synthesis of K2, B12, biotin, folate
• Metabolism of alcohols

Question 4

Probiotics

Answer 4

lactobacillus, bifidobacterium

Question 5

Human microbiome project

Answer 5

• comprehensive characterization of the human microbiome using metagenomics
• several sites of the body
• preterm births

Question 6

Commensals

Answer 6

ruminococcus, bacteroides, lactobacillus

Question 7

Mutualists

Answer 7

mostly metabolic

Question 8

Microbiome benefits

Answer 8

nutrient and micronutrient availability, energy extraction from food, barrier function, protection against pathogens, metabolism

Question 9

Canonical pathogens

Answer 9

• staph, e. coli
• need external introduction

Question 10

Opportunistic pathogens

Answer 10

• common in healthy individuals
• emerge from microbiome itself

Question 11

MetaHIT

Answer 11

• inflammatory bowel disease, obesity
• catalog microbial genes and genomes in human gut
• 3.3 million different genes among individuals analyzed

Question 12

archaea

Answer 12

• unique flagellins and lipids
• in skin, respiratory tract, urogenital tract, gastrointestinal tract

Question 13

Variation in microbiome

Answer 13

• highest between body sites
• next among different groups
• lowest among similar groups

Question 14

oral health

Answer 14

• periodontal disease associated with presence of bacteria
• dental plaque are biofilm formations of progressive microbial colonization

Question 15

Skin and nasopharynx

Answer 15

• corynebacterium and staphylococcus are prevalent
• most important mediator in protecting microbiome

Question 16

Airway

Answer 16

• pseudomonas aeruginosa common cause of cystic fibrosis
• asthma - haemophilus
• decreased diversity with disease

Question 17

esophagus

Answer 17

• proximal/mid - transient microbes from oropharynx and stomach
• distal - moderately diverse microbiome

Question 18

stomach

Answer 18

• h pylori domminant in stomach associated with ulcers
• diversity is low
• resilient

Question 19

intestine

Answer 19

• small - gradual increase from one end to other
• large - highly diverse
• reduced diversity linked to c diff

Question 20

vagina

Answer 20

• lactobacillus
• anaerobic bacteria

Question 21

origins of microbiome

Answer 21

• exposure in utero
• gestational age, infant feeding patterns, maternal diet, antibiotics associated

Question 22

Group B streptococcus

Answer 22

• universal screening at 35-37 weeks of gestation
• intrapartum antibiotic prophylaxis to prevent neonatal sepsis

Question 23

Dermatitis

Answer 23

staphylococci growing in specific areas of the skin

Question 24

Acne

Answer 24

Cutibacterium acnes

Question 25

Ventilator associated pneumonia

Answer 25

intubated patients show decreased diversity over timeI

Question 26

Intestine enterotypes

Answer 26

Bacteriodes, prevotella, ruminococcus