Question:
Which of the following is true about MRSA (methicillin-resistant Staphylococcus aureus) resistance?
Which of the following is true about MRSA (methicillin-resistant Staphylococcus aureus) resistance?
Show Hint
Think mecA and PBP2a, a changed target rather than an enzyme.
Updated On: Jun 24, 2026
- It is due to production of penicillinase
- It is due to alteration in penicillin binding proteins
- It is plasmid mediated
- It is treated with amoxicillin and clavulanic acid
Show Solution
Verified By Collegedunia
The Correct Option is B
Solution and Explanation
Step 1: Recall the mechanism of MRSA resistance. MRSA carries the mecA gene, which encodes an altered penicillin binding protein, PBP2a.
Step 2: PBP2a has very low affinity for beta-lactam antibiotics, so methicillin and other penicillins cannot bind and inhibit cell wall synthesis. This is the basis of resistance, confirming option B.
Step 3: Eliminate the wrong options. Penicillinase (beta-lactamase) production causes resistance to ordinary penicillin but is overcome by methicillin and by beta-lactamase inhibitors; it is not the MRSA mechanism. The mecA gene is chromosomal (carried on the SCCmec element), not plasmid mediated.
Step 4: Because resistance is due to an altered target rather than enzyme degradation, adding clavulanic acid (a beta-lactamase inhibitor) to amoxicillin does not work against MRSA.
Step 5: The correct statement is alteration in penicillin binding proteins, option B.
Step 2: PBP2a has very low affinity for beta-lactam antibiotics, so methicillin and other penicillins cannot bind and inhibit cell wall synthesis. This is the basis of resistance, confirming option B.
Step 3: Eliminate the wrong options. Penicillinase (beta-lactamase) production causes resistance to ordinary penicillin but is overcome by methicillin and by beta-lactamase inhibitors; it is not the MRSA mechanism. The mecA gene is chromosomal (carried on the SCCmec element), not plasmid mediated.
Step 4: Because resistance is due to an altered target rather than enzyme degradation, adding clavulanic acid (a beta-lactamase inhibitor) to amoxicillin does not work against MRSA.
Step 5: The correct statement is alteration in penicillin binding proteins, option B.
Was this answer helpful?
0
0
Top NEET PG Pharmacology Questions
- A bronchial asthma patient on inhalational steroids presented with white patchy lesions on the tongue and buccal mucosa. What is the drug that can be used to treat this condition?
- A pregnant woman with a history of bronchial asthma is in the third stage of labor. Which drugs should be avoided in managing postpartum hemorrhage in this mother?
- Name the drug that acts on both the marked areas.
- A patient with a previous history of myocardial infarction and ventricular arrhythmia is ontreatment for a few months. He developed fatigue, dyspnea, and weight gain. He had also developed pulmonary fibrosis. Which of the following drugs is responsible for the side effects mentioned above?
- A young female comes to the emergency department after consuming 100 aspirin tablets.What should be the next step in management?
View More Questions
Top NEET PG Questions
- A patient hailing from Delhi presents with fever, arthralgia, and extensive petechial rash for 3 days. Lab investigations revealed a hemoglobin of 9 g/ dL, a white blood cell count of 9000 cells/mm3, a platelet count of 20000 cells/mm3, and a prolonged bleeding time. The clotting time was normal. What is the most likely diagnosis?
- Which of the following statements is true about Trichomonas vaginalis?
- A lady from West Rajasthan presented with an ulcer surrounded by erythema on the right leg. Microscopy of the biopsy from the edge of the ulcer showed organisms with dark staining nuclei and kinetoplast. What is the most likely causative agent?
- A child presents with a fever and a rash. Urine examination showed cells with owl's eye appearance. What is the most likely diagnosis?
- Infection with Clonorchis sinensis is associated with an increased risk of__?
View More Questions