Systems-level analysis of NalD mutation, a recurrent driver of rapid drug resistance in acute Pseudomonas aeruginosa infection
Fig 6
RNA-seq analysis shows that the aztreonam-resistant isolate D+7bld up-regulates the mexAB-oprM efflux system and attenuates response to aztreonam stress.
(A) We compared the transcriptomes to reference isolate D-3rsw at 0μg/mL of aztreonam and found hundreds of differentially expressed genes. (B) The up-regulation of the mexAB-oprM efflux system in D+7bld supported that the NalD mutation released the transcriptional repression of mexAB-oprM. (C) The transcriptome of D+7bld at 4μg/mL aztreonam resembled the transcriptome of the aztreonam sensitive D-3rsw at half that dose (2μg/mL), confirming that the aztreonam resistance allows the strain to sustain higher levels of antibiotic challenge. azt, aztreonam. *, p-value<0.05.