Moderate

Penicillin is a kind of antibiotic that works as

Correct answer: D. Competitive inhibitor

  • A. Resistor
  • B. Uncompetitive inhibitor
  • C. Non-competitive inhibitor
  • D. Competitive inhibitor

Explanation

Penicillin is classified as a competitive inhibitor because it competes with the substrate for binding to the active site of the bacterial enzyme transpeptidase, which is crucial for cell wall synthesis. By occupying the active site, penicillin prevents the substrate from binding, effectively inhibiting the enzyme's activity and leading to the death of the bacteria.The other options are incorrect for the following reasons:Resistor: This term is not related to enzyme kinetics or inhibition and thus does not apply.Uncompetitive inhibitor: This type of inhibitor only binds to the enzyme-substrate complex, which does not represent how penicillin functions.Non-competitive inhibitor: Non-competitive inhibitors can bind to both the free enzyme and the enzyme-substrate complex, but penicillin specifically competes for the active site, which is characteristic of competitive inhibition.

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