A 7-year-old boy presents with acute otitis media (BP 105/68, HR 98, RR 22, Temp 38.5°C). Otoscopy reveals erythematous tympanum with fluid level; tympanometry confirms type B pattern. He is prescribed amoxicillin and has no reported penicillin allergy. The drug exerts its antibacterial effect by binding penicillin-binding proteins and inhibiting peptidoglycan cross-linking in the bacterial cell wall. Which of the following best describes the consequence of this mechanism of action?

  1. A)Inhibition of 30S ribosomal translocation
  2. B)Disruption of ergosterol synthesis in fungal membranes
  3. C)Activation of autolytic enzymes leading to bacterial lysisGABARITO
  4. D)Blockade of folate synthesis through dihydropteroate synthase inhibition
  5. E)Creation of DNA strand breaks by free radicals

Explicação

Beta-lactam antibiotics bind penicillin-binding proteins, which are transpeptidases required for cross-linking peptidoglycan. This weakens the bacterial cell wall and promotes activation of autolysins, leading to osmotic lysis. The stem directly describes the ... Ver explicação completa e trilha adaptativa →

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