Which of the following is NOT one of the five major mechanisms of antimicrobial resistance in microorganisms?

• A. Enzymatic degradation of the drug
• B. Increased uptake of the antimicrobial agent
• C. Alteration of drug target sites
• D. Efflux of the drug from the cell

Answer: (B)

Verified step by step guidance

1. Step 1: Understand that antimicrobial resistance mechanisms are strategies used by microorganisms to survive exposure to antimicrobial agents.
2. Step 2: Recall the five major mechanisms of antimicrobial resistance, which typically include: enzymatic degradation of the drug, alteration of drug target sites, efflux of the drug from the cell, decreased permeability to the drug, and bypass of metabolic pathways.
3. Step 3: Analyze each option given in the problem and compare it to the known mechanisms. For example, enzymatic degradation involves breaking down the drug, alteration of target sites changes the drug's binding location, and efflux pumps actively remove the drug from the cell.
4. Step 4: Identify that 'Increased uptake of the antimicrobial agent' is not a resistance mechanism because it would actually increase the drug's effectiveness rather than decrease it.
5. Step 5: Conclude that the correct answer is the option that does not fit the known resistance mechanisms, which is 'Increased uptake of the antimicrobial agent'.