TABLE 1.
The effect of NagZ on resistance in EC.
| Strain |
MICs (μg/ml) |
|||||
| TZP | ATM | PIP | CRO | CAZ | SCF | |
| S1+pBAD33 | 2 | 1 | 2 | 0.125 | 0.25 | 0.5 |
| S1+pBAD33-nagZ | 8 | 128 | 16 | 128 | 256 | 8 |
| S2+pBAD33 | 2 | 4 | 4 | 0.5 | 0.125 | 0.5 |
| S2+pBAD33-nagZ | 32 | >512 | 64 | 256 | 512 | 2 |
| S3+pBAD33 | 2 | 2 | 8 | 0.25 | 1 | 0.5 |
| S3+pBAD33-nagZ | 16 | 128 | 128 | 64 | 256 | 4 |
| S4+pBAD33 | 4 | 1 | 8 | 0.5 | 0.5 | 0.5 |
| S4+pBAD33-nagZ | 32 | 64 | 64 | 64 | 256 | 8 |
| S5+pBAD33 | 1 | 0.5 | 1 | 0.5 | 2 | 1 |
| S5+pBAD33-nagZ | 32 | 64 | 32 | 32 | 512 | 8 |
| S6+pBAD33 | 0.25 | 1 | 0.5 | 1 | 0.25 | 1 |
| S6+pBAD33-nagZ | 16 | 256 | 32 | 128 | 64 | 8 |
| R1 | 2 | 64 | 2 | 128 | 128 | 4 |
| R-ΔnagZ | 0.5 | 0.125 | 0.5 | 0.125 | 0.25 | 0.25 |
| R1-ΔnagZ+pBAD33 | 0.5 | 0.125 | 0.5 | 0.25 | 0.5 | 0.25 |
| R1-ΔnagZ+pBAD33-nagZ | 8 | 64 | 8 | 64 | 64 | 8 |
EC, Enterobacter cloacae; MIC, minimum inhibitory concentration; PIP, piperacillin; TZP, piperacillin-tazobactam; ATM, aztreonam; CRO, ceftriaxone; CAZ, ceftazidime; SCF, cefoperazone-sulbactam; S, susceptible EC isolated from the clinical sample; S1, susceptible EC isolates number 1, and so on; R1, resistant Enterobacter cloacae clinical isolates number 1; R1-ΔnagZ, nagZ knockout R1; pBAD33, control vector; pBAD33-nagZ, NagZ complementation vector; R1-ΔnagZ+pBAD33, R1-ΔnagZ complemented with pBAD33; R1-ΔnagZ+pBAD33-nagZ, R1-ΔnagZ complemented with pBAD33-nagZ.