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Old 07-20-2011
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Drug Trimethoprim effect on bacteria!

In an experiment, a colony of wild-type Staphylococcus aureus is assayed after 5 minutes of exposure to trimethoprim. Which of the following will be elevated intracellularly?
A. Dihydrofolic acid
B. Tetrahydrofolic acid
C. Dihydrofolate reductase
D. Dihydropteroate synthetase
E. Thymidine
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Old 07-21-2011
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a...trimethoprim is dihydrofolate reductase inhibitor..
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Old 07-21-2011
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ans is A, trimethoprim acts on dihydrofolate reducatase and inh the conversion of DHF TO THF. therefore DHF should be elevated, so the ans is A
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Old 07-21-2011
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Prone to A; DHF -> THF conversion is blocked so DHF will be accumulated.
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