8.13_Flora/Biome

Question 1

Microbiota versus microbiome

Answer 1

microbiota is the actual organisms and the microbiome is the genes of those organisms, way more anaerobic than aerobic, and majority in GI and mouth

not much is cultivable but we have found ways to see it through culture independent techniques

Question 2

Make up of the microbiota

Answer 2

mainly frimicutes (include g+) and bacteroidetes, only about 1% proteobacteria or g–

Question 3

Microbiota origin

Answer 3

from placenta, and amniotic fluid from mothers digestive tract, breast milk, vaginal flora as we exit

Question 4

Colonization resistance

Answer 4

good guys in microbiota occupy spots where bad guys could go and colonize so it is a preventative measure, antibiotics clear these spaces

Question 5

Antibiotic associated clostridium difficile disease

Answer 5

C difficile is part of normal gut, has spores that are typically inactive and stable, but if antibiotic wipes out normal gut flora then spores can activate and c difficile predominates

Question 6

Roles of gut microbes

Answer 6

digestion, make vitamines B and K, occupy niches to prevent pathogens, and train immune system to know they are the good guys and to not attack them

Question 7

Diseases linked to microbiota

Answer 7

IBS, crohns, IBD, obesity, type I and II diabetes, asthma and autism??

Question 8

Skin flora

Answer 8

Staphylococcus epidermidis

Question 9

Nose flora

Answer 9

S. aureus

Question 10

Vaginal flora

Answer 10

lactobacillus species

Question 11

GI Flora

Answer 11

Bacteroidetes and Firmicutes gram+

Question 12

GI Flora

Answer 12

E coli and clostridium species

Question 13

Sessile bacteria

Answer 13

growing in biofilm, attached to a surface

Question 14

Planktonic bacteria

Answer 14

free floating and motile bacteria not attached to a surface

Question 15

Polysaccharide capsule

Answer 15

extracellular but attached to gram +/- bacterial surface

Question 16

exopolysaccharides

Answer 16

secreted beyond bacterial envelope into environment, do not remain attached to individual bacteria

Question 17

Stages of biofilm growth

Answer 17

1. reversible attachment-must find a surface to attach to
2. irreversible attachment- start to grow biofilm
3. exopolysaccharide production- provides protection from antibiotics and antibodies and makes larger
4. formation of 3d structure
5. Dispersal- let go of some bacteria

Question 18

Biofilm problems

Answer 18

form on healthcare equipment, better defense against drugs and antibodies, bacteria within is not always uniform