Can anyone explain, Why does aztreonam ineffective against gram-positive bacteria, Is the permeability a reason or poor affinity towards PBP3 of Gram +ive bacteria? please explain.
It’s the affinity issue – ATM has a high affinity to penicillin-binding protein 3 (PBP3) of Gram-negative bacteria, but doesn't bind well to PBP's of aerobic Gram-positives.
@Oliver Nolte Thankyou sir for the confirmation but do you have any reference where a weaker binding towards Gram-positive bacteria reported? It will be really very useful.