Antibiotic Mech of Action

Question 1

Aminoglycosides

Answer 1

Irreversibly bind to 30S ribosomal subunit and inhibit protein synthesis
Can disrupt proofreading in bacterial protein synthesis
Requires O2 dependent cotransporter to be transported into the cell

Question 2

Antimetabolites

Answer 2

Interferes with the synthesis of DNA
Specifically inhibits bacterial folate syntheses

Question 3

Sulfonamides

Answer 3

Inhibit DHPS –> prevents formation of dihydropteroic acid

Question 4

Trimethoprim

Answer 4

inhibits DHPS –> prevents formation of tetrahydrofolic acid

Question 5

Trimethoprim/Sulfamethoxazole (Bactrim)

Answer 5

Blocks folate synthesis at both steps

Question 6

Tetracyclines

Answer 6

Binds to the 30S subunit of bacterial ribosomes and inhibits protein synthesis

Question 7

Tigecycline

Answer 7

Modified tetracyclines with an extra dimethylglycoamido side chain that prevents them from binding to bacterial enzymes so they don’t get broken down

Question 8

Penicillins

Answer 8

Inhibit cell wall synthesis in bacteria
PBP enzymes mistakenly bind to beta lactam antibiotic molecule which permanently disables it

Question 9

Cephalosporins

Answer 9

Inhibits bacteria cell wall synthesis

Question 10

Metronidazole

Answer 10

Inhibits synthesis of DNA in bacteria and other organisms
Inhibits CYP450 enzymes

Question 11

Fluoroquinolones

Answer 11

Inhibits DNA replication by disabling DNA topoisomerase II and DNA topoisomerase IV

Question 12

Chloramphenicol

Answer 12

Prevents peptide bond formation between new amino acids and the polypeptide chain to inhibit protein synthesis
Inhibits CYP450 enzymes

Question 13

Macrolides

Answer 13

Binds to the 50S subunit of the ribosome and blocks translocation
Ribosome can’t slide to the next codon on the mRNA which inhibits protein synthesis

Question 14

Lincosamides

Answer 14

Binds to the 50S subunit of the ribosome and inhibits translocation
Inhibits protein synthesis

Question 15

Oxazolidinones

Answer 15

Binds to the 50S subunit of the ribosome and prevents it from combining with the 30S subunit
Inhibits protein synthesis

Question 16

Bactoprenol Inhibitors

Answer 16

Bacitracin blocks bactoprenol phosphate
Bacteria can’t make new peptidoglycan
Inhibits cell wall synthesis

Question 17

Beta Lactamase Inhibitors

Answer 17

Once inside the bacteria, they bind permanently to beta lactamase enzymes which disables them
Allows the penicillins to work

Question 18

Carbapenems

Answer 18

Binds to PBP’s and inhibits cell wall synthesis
Have a modified ring which makes beta lactamases unable to bind to medication

Question 19

Monobactams

Answer 19

Beta lactam ring is not fused to any other ring and sticks out on its own
This makes it resistant to beta lactamases

Question 20

Glycopeptides

Answer 20

Latches onto the tetrapeptide chains and prevents them from being linked to PBP enzymes
Inhibits cell wall synthesis