Antibiotics — Flashcards

Flashcard 111: Aminoglycosides bind the _____ ribosomal subunit, irreversibly inhibiting formation of the _____

Answer: 30S

Flashcard 112: Which enzyme is inhibited by trimethoprim (TMP)? _____

Answer: Dihydrofolate reductase (prokaryotic)

Flashcard 113: What is the treatment for Staph aureus infections (not MRSA)? _____

Answer: Nafcillin

Flashcard 114: Neomycin is an aminoglycoside applied _____ or ingested to reduce gut ammonia levels (e.g. in hepatic encephalopathy)

Answer: topically

Extra: Neomycin is used topically (e.g., in ointments), for bowel preparation before surgery, and for hepatic encephalopathy.

Flashcard 115: Rifamycins can cause minor _____toxicity

Answer: hepato

Flashcard 116: Isoniazid _____ cytochrome p450

Answer: inhibits

Flashcard 117: Isoniazid (INH) is a prodrug that is activated by _____, which is produced by Mycobacteria tuberculosis

Answer: KatG (a catalase-peroxidase)

Flashcard 118: A patient has recently been scratched by a cat and develops a febrile lymphadenitis, what two classes of drugs can you use? _____

Answer: Tetracyclines and Macrolides

Flashcard 119: Pyrazinamide is converted to its active form, which _____.

Answer: disrupts mycobacterial cell membrane metabolism and transport functions

Extra: Conversion to the active form (pyrazinoic acid) requires the enzyme **pyrazinamidase**.

Flashcard 120: What antibiotics are used to treat hepatic encephalopathy? _____

Answer: rifaximin and neomycin