Table 3 Results of the gene mutations of gyrA and parC for selected strains from the different treatment groups, the minimal inhibitory concentration (MIC) values are also provided for these isolates with wild-type cut-off of 0.125 μg/mL. The silent mutations, i.e. polymorphisms in codon sequence resulting in the same amino acid, in gyrA and parC are given, with the reference sequences indicated in grey. Escherichia coli K12 MG1655 was used for reference
Isolate | MIC (μg/mL) | gyrA mutations | parC mutations | Silent mutations (gyrA/ parC) and additional resistance mechanisms |
|---|---|---|---|---|
E. coli K12 MG1655 | NA | None | None | REFERENCE gyrA: 85GTC, 91CGC, 100TAT, 110TCT /parC: 91CAA |
ATCC 25922â„¢ | 0.064 | None | None | Â |
Y01.V2 – Group 1 – 0 h | 0.064 | None | None |  |
Y08.V3 – Group 2 – 0 h | 0.032 | None | None |  |
Y11.V2 – Group 3 – 0 h | 0.016 | None | None |  |
Y12.V2 – Group 4 – 0 h | 0.064 | None | None |  |
X02.V2 – Group 1 – 0 h | 2.00 | None | None | gyrA: 85GTT, 91CGT, 100TAC, 110TCC/ parC: 91CAG and qnrS1 positive |
Y02.V2 – Group 2 – 0 h | 4.00 | None | None | gyrA: 85GTT, 91CGT, 100TAC, 110TCC/ parC: 91CAG and qnrS1 positive |
X06.V2 – Group 2 – 0 h | 4.00 | None | None | gyrA: 85GTT, 91CGT, 100TAC, 110TCC/ parC: 91CAG and qnrS1 positive |
Y09.V2 – Group 3 – 0 h | 2.00 | None | None | gyrA: 85GTT, 91CGT, 100TAC, 110TCC/ parC: 91CAG and qnrS1 positive |
X12.V2 – Group 4 – 0 h | 1.00 | None | None | gyrA: 85GTT, 91CGT, 100TAC, 110TCC/ parC: 91CAG and qnrS1 positive |
X04.V2 – Group 1 – 58 h | > 32.00 | 83Leu, 87Asn | 80Ile |  |
X07.V3 – Group 2 – 58 h | > 32.00 | None | None |  |
X08.V4 – Group 2 – 58 h | > 32.00 | 83Leu, 87Asn | 80Ile |  |
X09. V4 – Group 2 – 58 h | > 32.00 | 83Leu, 87Asn | 80Ile |  |
X11.V6 – Group 3 – 58 h | > 32.00 | 83Leu, 87Asn | 80Ile |  |
X13.V1 – Group 4 – 58 h | > 32.00 | 83Leu, 87Asn | 80Ile |  |
X14.V1 – Group 4 – 58 h | > 32.00 | 83Leu, 87Asn | 80Ile |  |
X15. V1 – Group 4 – 58 h | > 32.00 | 83Leu, 87Asn | 80Ile |  |