Table 1.
Chromosomally encoded or imported resistance mechanisms of P. aeruginosa.
| Location | Resistance mechanisms | Targeted antibiotics | Type of resistance |
|---|---|---|---|
| Intrinsic (chromosomal) | AmpC–type cephalosporinase | β-lactams | Antibiotic inactivation |
| Class D oxacillinase OXA-50 | β-lactams | Antibiotic inactivation | |
| Aminoglycosides inactivating enzymes | Aminoglycosides | Antibiotic inactivation | |
| Efflux systems (overexpression) | Multiple antibiotic classes | Efflux systems | |
| Decreased membrane permeability | Multiple antibiotic classes | Membrane impermeability and purines | |
| DNA gyrase and topoisomerase IV | Fluoroquinolones | Target modification | |
| LPS modification | Colistin | Target modification | |
| Imported (Mobile genetic elements) | Class A serine β-lactamases (PSE, CARB, TEM) | β-lactams | Antibiotic inactivation |
| Class A serine ESBL (TEM, SHV, CTX-M, PER, VEB, GES, IBC) | β-lactams | Antibiotic inactivation | |
| Class D ESBL (OXA-types) | β-lactams | Antibiotic inactivation | |
| Class B Metallo-β-lactamase (IMP, VIM, SPM, GIM) | Carbapenems | Antibiotic inactivation | |
| Class A serine carbapenemase (KPC) | Carbapenems | Antibiotic inactivation | |
| Class D carbapenemase (OXA-types: OXA-40) | Carbapenems | Antibiotic inactivation | |
| Aminoglycosides inactivating enzymes | Aminoglycosides | Antibiotic inactivation | |
| Ribosomal methyltransferase enzymes | Aminoglycosides | Target modification |