TABLE 2.
Variations of resistance mechanisms in multiresistant P. aeruginosa isolates
| Strain | β-Lactamase activity (nmol/min/mg of protein) | Expressiona
|
Sequence of mexZb | |
|---|---|---|---|---|
| oprD | mexX | |||
| PAO1 | 72 | 1.00 | 1.00 | |
| Positive control | >22c | |||
| PFGE type A1 | 5,100 | 0.02 | 49.4 | GAC→G_C (164) |
| PFGE type K1 | 3,500 | 0.2 | 3.6 | |
a
mRNA quantification by RT-PCR. Numerical value are expressed relative to PAO1, which is set at 1.00.
b
Nucleotide sequence compared with the PAO1 genome (www.pseudomonas.com).
c
Mut-Gr1 strain overproducing MexXY was used as a positive control (29).