Table 3 Overview of combined mechanism of ciprofloxacin resistance within qnrS, acrAB-tolC positive Enterobacteriaceae
Organism | ID | MIC (µg/mL) | Plasmid mediated qnrS gene | Efflux pump mediated resistance | Amino acid substitution in QRDR of DNA gyrase subunit A | |||
|---|---|---|---|---|---|---|---|---|
No. of plasmids extracted (approximate size in kb) | Size (in kb) of plasmid harboring qnrS gene | Effect of NMP on the action of CIP | Amino acid substitution in regulatory gene products | |||||
AcrR | MarR | |||||||
Escherichia spp. | E23 | 512 | No plasmid | – | Additive | H115Y | G103S, Y137H, A53E | S83L, D87N |
E34 | 512 | No plasmid | – | Additive | H115Y | G103S, Y137H, A53E | S83L, D87N | |
26N | 256 | 5 (<2.1, 2.7, 3.0, 4.6, >54.2) | 1 (<2.0) | Additive | H115Y | G103S, Y137H, A53E | S83L, D87N | |
28N | 256 | 6 (<2.1, <2.1, 2.5, 2.8, 3.1, 3.9) | None | Additive | T213I, N214T | G103S, Y137H, K62R | S83L, D87N | |
CR1 | 512 | 1 (>54.2) | 1 (>54.2) | Synergistic | No substitution | G103S, Y137H | S83L | |
CR2 | 512 | 7 (~2.3, 2.5, 3.7, 3.9, 5.2, 54.2, >54.2) | 1 (>54.2) | Synergistic | No substitution | G103S, Y137H | S83L, D87N | |
CR4 | 512 | 5 (<2.1, 2.9, 3.0, 3.5, >54.2) | None | Synergistic | ND | ND | S83L, D87N | |
MCX14 | 256 | 2 (3.1, >54.2) | 1 (>54.2) | Additive | ND | ND | S83L, D87N | |
NCX9 | 256 | 2 (~54.2, >54.2) | None | Additive | No substitution | G103S, Y137H | No substitution | |
G4 | 256 | 4 (~2.4, 2.7, 3.9, >54.2) | None | Additive | T213I, N214T | G103S, Y137H, K62R | S83L, D87N | |
Enterobacter spp. | MCX5 | 512 | 5 (2.0, 2.2, 2.8, 3.9, >54.2) | None | Synergistic | ND | ND | S83L, D87N |
MCX6 | 256 | 3 (2.0, 2.2, >54.2) | 1 (2.2) | Additive | ND | ND | S83Y | |
NCX14 | 256 | 1 (3.9, 7.0) | 2 (3.9, 7.0) | Additive | ND | ND | S83L, D87N | |
Klebsiella spp. | E33 | 256 | No plasmid | – | Additive | ND | ND | Not done |
NCX6 | 512 | 9 (<2.0, 2.0, 2.5, 3.0, 3.5, 4.8, 5.0, 54.2, >54.2) | None | Synergistic | ND | ND | Not done | |
MCX10 | 512 | 8 (<2.0, 2.5, 2.7, 3.9, 4.0, 5.0, 54.2, >54.2) | 3 (2.5, 2.7, >54.2) | Synergistic | ND | ND | S83L | |
Salmonella spp. | 74 | 256 | No plasmid | – | Additive | ND | ND | S83L, D87N |
77 | 512 | No plasmid | – | Additive | ND | ND | S83L, D87N | |