Antibiotics in the Food Supply

Question 1

Why is antimicrobial resistance a cause for concern

Answer 1

increased difficulty to treat infections; deaths + cost health care systems 2 billion dollars

Question 2

Does banning of antibiotics work?

Answer 2

yes after you have a levelling off, even a decrease of the AMR in the community. but it can also be problematic.

Question 3

what is AMR

Answer 3

antimicrobial resistance decreased susceptibility of multiple microbes to a broad spectrum of single/multiple antibiotics

Question 4

how can agricultural use of antibiotics affect human health

Answer 4

use in animals –> selects for the presence of ARGS (antibiotic resistant genes and ARBS (antibiotic resistant bacteria).

manure –> environment gain more ARG and ARB –> vegetables –> consumed (genes for resistance enter body)

Question 5

what are the mechanisms behind antibiotics?

Answer 5

1. inhibit protein synthesis
2. inhibit cell wall synthesis
3. inhibit DNA synthesis
4. Inhibit folic acid synthesis

Question 6

the main purposes of antibiotics in agriculture

Answer 6

1. prevent disease
2. treat disease
3. growth promotion

Question 7

2 categories to classify antibiotics and describe each category + provide examples of each.

Answer 7

1. bacteriocidal (kill) –> target key structures (cell wall and DNA) ex. beta lactams and aminoglycosidases
2. bacteriostatic (inhibit growth); target non essential process (protein synthesis); macrolides and tetracyclines

Question 8

AMR desribes decreased susceptibility of a _______ to a _______ antibiotics

Answer 8

multitude of microbes to a broad spectrum of single or multiple antibiotics.

Question 9

Describe the disk diffusion method?

Answer 9

It is the test of the sensitivity of bacteria to a specific antibiotic. It uses antibiotic discs which are placed on agar plates containing a lawn of bacteria and the plate is left to incubate.

• zone of inhibitior.; depends on factors like how effective antibiotic is at stopping the growth, rate of diffusion and molecular configuration.
• compare to database; susceptible, moderately susceptible or resistant to antibiotic in question.

Question 10

Describe MIC test strips

Answer 10

lowest concentration of a drug at which no visible growth occurs. after incubation on bacterial lawn, an ellipse shaped growth forms on the agar plate. where the elipse meets the strip = MIC can be determined from the markings.

Question 11

Describe MIC Plate

Answer 11

Sensititre MIC plates are 96-well plates that contain lyophilized antibiotics configured to determine the MIC to a variety of antibiotics
Dilutions of bacteria with a usable carbon source are inoculated into each well of the plate
The plates can be inspected visually or with a plate-reader to determine the MIC for each antibiotic