WBR0642

Author	[[PageAuthor::Rim Halaby, M.D. [1]]]
Exam Type	ExamType::USMLE Step 1
Main Category	MainCategory::Microbiology, MainCategory::Pharmacology
Sub Category	SubCategory::Infectious Disease
Prompt	[[Prompt::A pharmaceutical company is trying to develop a new antibiotic to overcome increasing resistance to macrolides. Their rationale is to create an agent that would be co-administered with azithromycin that counteracts the mechanism by which bacteria become resistant to this antibiotic. Which of the following agents would be appropriate to investigate for this purpose?]]
Answer A	AnswerA::
Answer A Explanation	AnswerAExp::
Answer B	AnswerB::
Answer B Explanation	AnswerBExp::
Answer C	AnswerC::
Answer C Explanation	AnswerCExp::
Answer D	AnswerD::
Answer D Explanation	AnswerDExp::
Answer E	AnswerE::
Answer E Explanation	AnswerEExp::
Right Answer	RightAnswer::
Explanation	[[Explanation:: Macrolides are a class of antibiotic agents that act by inhibiting protein synthesis specifically inhibiting translocation. They bind to the 23S rRNA binding site of the 50S subunit. They are commonly used to treat atypical pneumonias, chlamydia, and non-tuberculous mycobacteria among others. The mechanism of resistance to macrolides is by the methylation of the 23S rRNA binding site. A suggested mechanism to inhibit resistance it to administer an agent to inhibit bacterial methylation enzymes. Learning Objective: Resistance to macrolides is by methylation of the 23S rRNA binding site. References: Walsh C. Molecular mechanisms that confer antibacterial drug resistance. Nature. 2000;406(6797):775-81. Educational Objective: References: ]]
Approved	Approved::No
Keyword
Linked Question	Linked::
Order in Linked Questions	LinkedOrder::