Antibiotics II

Question 1

What are the Cell wall inhibitors?

Answer 1

Penicillins: end in -cillin
Cephalosporins: Begin with Ceph-
Beta Lactamase inhibitors: Clavulanic acid
Monobactam: Aztreonam
Glycopeptides: Vancomycin
Polypeptides: Bacitracin
Carbapanems: end in -penem
Phosphoenolpyruvate: Fosfomycin

Question 2

What are agents that target the cell membrane?

Answer 2

Lipopeptides: Daptomycin
Detergents: Polymyxin B

Question 3

What are protein synthesis inhibitors:

Answer 3

Tetracyclines: end in -cycline
Aminoglycosides: end in -mycin except for Amikacin
Macrolides: End in -mycin ACE
Others: Clindamycin, Chloramphenicol, Linezolid

Question 4

What are folate synthesis inhibitors
Gyrase inhibitors
DNA damagers?

Answer 4

Sulfonamides: Start with Sulfa-
Trimethoprim: have -meth- in the name
Fluoroquinolones: end in -floxacin
Metronidazole: Metronidazole

Question 5

What are key steps in cell wall synthesis?

Answer 5

Penicillin binding proteins are important.
transglycosylase joins NAM NAG monomers
Transpeptidase add crosslinks

Question 6

Penicillin (beta lactam abx)
MOA:
Adverse Effects:

Answer 6

MOA: Inhibit PBP enzymes
Adverse Effects: Hypersensitivity reaction (rash, hives, etc)
Other: Broad spectrum: Ampicillin, Amoxicillin
Extended Spectrum: piperacillin, Ticarcillin, Azlocillin
Resistance: Exp of Beta Lactamase, altered PBP, altered porin function

Question 7

What are Beta Lactamase Inhibitors?
MOA:
Adverse Effects:

Answer 7

Clavulanic Acid, used with penicillin to inc effect
MOA: Inhibit Beta Lactamase
Adverse Effects: Hypersensitivity reaction

Question 8

Cephalosporins - Beta Lactam abx
MOA:
Adverse Effects:

Answer 8

MOA: Inhibit Penicillin Binding Proteins
Adverse Effects: Hypersensitivity Rxns
4th generation is broadest spectrum, 1 is narrowest
4th gen: Cefepime - Ender CNS
1st gen: Cefazolin, Cephalexin - NO enter CNS
Resistance: Exp of Beta Lactamase, altered PBP, altered porin function

Question 9

Monobactam Compounds - Beta Lactam abx
MOA:
Adverse Effects:

Answer 9

Aztreonam
MOA: Bind and inhibit the Penicillin Binding proteins
Adverse Effects: Hypersensitivity Rxn - mild/mod

Question 10

Carbapenems - Beta Lactam abx
MOA:
Adverse Effects:

Answer 10

end in -penem
MOA: Bind and inhibit Penicillin Binding Proteins
Adverse Effects: GI effects, Hypersensitivity, htn, CNS

Question 11

Glycopeptide abx - others
MOA:
Adverse Effects:

Answer 11

Vancomycin
MOA: Prevents elongation of cell wall, binds to D-ala-D-ala pentapeptide
Adverse Effects: Flushing (Red neck, “red man syndrome”

Question 12

Polypeptides - others
MOA:
Adverse Effects:

Answer 12

Bacitracin
MOA: Blocks incorporation of amino acids and nucleic acids into cell wall
Adverse Effects: Hypersensitivity Rxn
Topical

Question 13

Phosphoenolpyruvate- others
MOA:
Adverse Effects:

Answer 13

Fosfomycin
MOA: Blocks early step in cell wall synthesis
Adverse Effects: Hypersensitivity rxn

Question 14

Aminoglycosides - Prot Synth inhib
MOA:
Adverse Effects:

Answer 14

end in -mycin
MOA: Binds 30S and blocks formation of initiation complex
Adverse Effects: Nephrotoxicity, Ototoxicity
Resistance: Express enzymes that alter chemical structure of drug

Question 15

Macrolides - Prot Synth Inhib
MOA:
Adverse Effects:

Answer 15

end in -thromycin
MOA: Bind to 50S subunit and inhibit translocation to the “P” site
Adverse Effects: GI symptoms
Resistance: Drug Efflux

Question 16

Tetracycline - Prot Synth Inhib
MOA:
Adverse Effects:

Answer 16

end in -cycline
MOA: Bind 30S subunit and prevent new tRNA binding to the “A” site
Adverse Effects: Nutrient interaction, Ecological effects (normal flora), photosensitivity
Resistance: Drug Efflux

Question 17

Clindamycin - Prot Synth Inhib - other
MOA:
Adverse Effects:

Answer 17

Narrow spectrum, MRSA
MOA: Binds 50S subunit, prevents formation of initiation complex AND translocation to “P” site
Adverse Effects: GI effects (C. Diff)

Question 18

Chloramphenicol - Prot Synth Inhib - other
MOA:
Adverse Effects:

Answer 18

rarely used
MOA: Binds 50S subunit and prevents peptide bond formation
Adverse Effects: Blood (no red cell prod), Gray Baby Syndrome (infants lack glucuronic acid conjugation
Resistance: Inactivating enzymes

Question 19

Oxazolidinones - Prot Synth Inhib - other
MOA:
Adverse Effects:

Answer 19

Linezolid - Effective against DRUG RESISTANT BACTERIA
MOA: Inhibits protein synthesis
Adverse Effects: Blood - myelosuppression

Question 20

Sulfonamides - DNA synthesis inhib - antifolate
MOA:
Adverse Effects:

Answer 20

begin with Sulfa-
MOA: Similar to PABA, inhib dihydropteroate synthase
Adverse Effects: Skin: hypersensitivity, photosensitive, SJS
Resistance: Less Sensitive target, Increased PABA secretion, scavenge for folic acid

Question 21

Trimethoprim - DNA synthesis inhib - antifolate
MOA:
Adverse Effects:

Answer 21

Trimethoprim and Pyrimethamine
MOA: Inhib Bacterial dihydrofolate reductase
Adverse Effects: Blood: Bone marrow suppression

Question 22

Trimethoprim-Sulfamethoxazole - DNA synthesis inhib
MOA:
Adverse Effects:

Answer 22

UTI
MOA: Synergistic when combined
Adverse Effects: effects of both

Question 23

Fluoroquinolones - DNA synthesis inhib
MOA:
Adverse Effects:

Answer 23

end in -floxacin
MOA: inhibit Topoisomerase II
Adverse Effects: GI, Drug-Nutrient (Ca absorp), Cardio (QT prolong)
Resistance: Less sensitive target, Drug Efflux

Question 24

Metronidazole - DNA damage
MOA:
Adverse Effects:

Answer 24

tx of C. Diff
MOA: Prodrug, binds to DNA and disrupts function/damage
Adverse Effects: GI, Metabolism (disulfiram effect)

Question 25

Lipopeptide - Cell Membrane
MOA:
Adverse Effects:

Answer 25

Daptomycin
MOA: Binds membrane and depolarizes
Adverse Effects: Muskuloskeletal system

Question 26

Detergents - Cell Membrane
MOA:
Adverse Effects:

Answer 26

Polymixin B - topical
MOA: Punch holes in membrane
Adverse Effects: Rare