Animal Microbial Resistance

Question 1

What antibiotics target the cell wall

Answer 1

Beta lactam, glycopeptides, bacitracin

Question 2

What antibiotics target DNA

Answer 2

Fluoroquinolones, novobiocin, nitroimidazoles

Question 3

What antibiotics target ribosomes

Answer 3

Tetracyclines, aminoglycosides, lincosamindes

Question 4

How do beta-lactams work

Answer 4

They bind the active site in transpeptidases (penicillin binding proteins) and stop the crossing linking between peptide and sugar chains
This is because the antibiotics are similar to the natural peptidoglycan subunits (D-Ala-D-ala)

Question 5

All beta-lactam antibiotics contain…

Answer 5

The same core 4-member beta-lactam ring (the shape that mimics the terminal D-ala-D-Ala that is the substrate for the transpeptidase)

Question 6

4 general resistance mechanisms to beta-lactams

Answer 6

Penetration (intracellular bacteria)
Porins (gram negative)
Pumps (gram neg can have ABC transporters)
Peptidoglycan is absent (mycobacteria)

Question 7

2 specific resistance mechanisms to beta-lactams

Answer 7

1. penicillinases (beta-lactamases)

2. PBPs (does not bind beta-lactams)

Question 8

What are 3 levels of threat that AMR has on humanity

Answer 8

Global health, food security and development/economics

Question 9

By 2050, how many people will die annually due to AMR

Answer 9

10 million

Question 10

When was penicillin discovered

Answer 10

1928

Question 11

When were sulphonamides marketed for routine use in agriculture

Answer 11

1938

Question 12

What drug was found to increase the rate at which poultry gained weight

Answer 12

Aureomycin

Question 13

What was used to prevent coccidiosis in broilers

Answer 13

Sulfaquinoxaline

Question 14

By 1998, how many S. aureus isolated were resistant to penicillin

Answer 14

95%

Question 15

What are most chickens and cattle fed in North america

Answer 15

Chickens: bacitracin, ionophores
Cattle: ionophores

Question 16

What are beef cattle fed prophylactically with

Answer 16

Ceftiofur (category 1)

Question 17

What is the WHO five-step approach to fighting AMR

Answer 17

1. Improve awareness and understanding
2. Strengthen surveillance
3. Reduce incidence of infection
4. Optimize AM medicines
5. ensure sustainable investment in countering antimicrobial resistance

Question 18

What is canada’s 3 pronged approach to combatting AMR

Answer 18

Surveillance, stewardship (conserving effectiveness of existing treatments) and innovation

Question 19

What is Canada’s approach stewardship

Answer 19

Antibiotics are categorized into 4 groups based on importance in human medicine (specific warnings for categories 1-3

Question 20

Synercid

Answer 20

Semi-synthetic antibiotic that is approved to treat MRSA

Question 21

Virginiamycin

Answer 21

Approved for feed in a broiler chickens and swine

Question 22

What is the connection between synercid and virginiamycin

Answer 22

Virginiamycin acetyltransferases confer resistance to synercid

Question 23

What is MCR-1

Answer 23

It confers resistance to colistin and bacitracin

Question 24

What can be used to replace antibiotics

Answer 24

Improved hygiene, bacteriophages, probiotics, antibiotic derivatives