Amoxicillin + clavulanic acid is active against the following organisms EXCEPT :
Staphylococcus aureus develops resistance to methicillin by acquiring altered penicillin-binding proteins that have low affinity. No Beta-lactam antibiotic is effective against MRSA.
Clavulanic acid is an inhibitor of β-lactamase. It can restore the sensitivity of penicillins against the organisms who have developed penicillinases.
Methicillin resistant Staph. aureus
Penicillinase producing Staph. aureus
Penicillinase producing N. gonorrhoeae
β-lactamase producing E. coli