Introduction to Microbiology: Mechanisms of Antibiotic Medications

Flashcards covering key concepts: bactericidal vs. bacteriostatic, generic vs. trade names, and major antibiotic classes and examples by mechanism (cell wall, membrane, protein synthesis, nucleic acid synthesis, and metabolic targets).

What is the difference between bactericidal and bacteriostatic antibiotics?

Bactericidal antibiotics kill bacteria; bacteriostatic antibiotics inhibit growth or replication without necessarily killing them immediately.

Which antibiotic classes target bacterial cell wall synthesis?

β-lactams (penicillins, cephalosporins, monobactams, carbapenems) and glycopeptides (vancomycin) and bacitracin.

Name examples of β-lactam antibiotics listed.

Penicillins (penicillin G, penicillin V, amoxicillin); Augmentin (amoxicillin/clavulanic acid); cephalosporins (cephalexin, ceftriaxone, cefepime, cefuroxime); imipenem (carbapenem).

What are the glycopeptide and peptide antibiotics mentioned?

Vancomycin; Bacitracin; (and daptomycin is a lipopeptide, not a glycopeptide, but listed under membrane-targeting agents).

Which antibiotics target the plasma membrane?

Polymyxins (polymyxin B, colistin) and daptomycin (a lipopeptide).

Which antibiotics target the 30S ribosomal subunit?

Aminoglycosides (e.g., amikacin, gentamicin) and tetracyclines (e.g., tetracycline, doxycycline).

Which antibiotics target the 50S ribosomal subunit?

Macrolides (e.g., azithromycin), lincosamides (clindamycin), chloramphenicol, and oxazolidinones.

Which antibiotics inhibit DNA synthesis?

Fluoroquinolones (e.g., ciprofloxacin, levofloxacin, moxifloxacin).

Which antibiotics inhibit RNA synthesis?

Rifamycins (e.g., rifampin).

Which drugs target folic acid synthesis?

Sulfonamides, sulfones, and trimethoprim.

Which drug inhibits mycolic acid synthesis?

Isoniazid.

What are examples of aminoglycosides listed?

Amikacin and Gentamicin.

What are examples of tetracyclines listed?

Tetracycline and Doxycycline.

What are examples of macrolides listed?

Azithromycin.

What are examples of lincosamides listed?

Clindamycin.

Which drugs are examples of fluoroquinolones listed?

Ciprofloxacin, Levofloxacin, and Moxifloxacin.

What is Augmentin?

Amoxicillin combined with clavulanic acid (a β-lactamase inhibitor).

Name penicillin examples listed.

Penicillin G, Penicillin V, Amoxicillin, Methicillin.

Name cephalosporin examples listed.

Cephalexin, Ceftriaxone, Cefepime, Cefuroxime.

What carbapenem is mentioned?

Imipenem.

What class does vancomycin belong to?

Glycopeptide.

What is bacitracin’s classification?

A peptide antibiotic that targets cell wall synthesis (topical use primarily).

Why are gram-positive pathogens easier to treat than gram-negative pathogens?

Gram-positive bacteria lack the outer membrane barrier that Gram-negative bacteria possess, making them more permeable to many antibiotics and generally easier to treat.