influenzae, 3, 15 as follows: gBLNAS, -lactamase-negative isolates that are ampicillin susceptible without resistance. parainfluenzae T3T1, 7, 13 we used the same genotype classification as that already used for H. These drugs are only active against gram-negative rods. Due to the high degree of nucleotide (78) and amino acid (83) homology between ftsI and PBP3 of H. Monobactams are also resistant to penicillinase, a bacterial enzyme that can deactivate penicillins by cleaving the beta-lactam ring. Chloramphenicol agent is an irreversible inhibitor of. Like penicillins, these drugs are beta-lactam antibiotics they are D-Ala-D-Ala analogs that bind to and block the bacterial transpeptidase, thereby preventing the cross-linking of the bacterial cell wall. By binding to PBP3, aztreonam agents inhibit the third and last stage of peptidoglycan synthesis. Cells grown for approximately half a mass doubling time in the presence of. Therefore, despite its dependency on active PBP3 for localization at mid-cell, it seems not to be an integral part of the divisome. One important monobactam to know is Aztreonam. In contrast to subunits of the divisome, PBP2 failed to localize at mid-cell when PBP3 was inhibited by the specific antibiotic aztreonam. Summary Monobactams are a class of antibiotics used to treat gram negative bacterial infections.