Table 1.

Comparison of the extents of altered expression of selected genes and operons observed for tobramycin microarrays and resistant mutant screense

Gene or operonExtent of altered regulationaTOB resistance geneb
Aerobic WT (TOB at 2 μg/ml)Anaerobic WT (TOB at 20 μg/ml)Aerobic WT (TOB at 0.25 μg/ml)Anaerobic WT (TOB at 2 μg/ml)Aerobic PA0779 (asrA::lux) (TOB at TOB 2 μg/ml)
Heat shock
    groES groEL+++++
    dnaJ dapB+++++++
    grpE dnaK++++++++
Energy metabolism
    sucAB lpdG
Denitrification/nitrogen metabolism
    Pilus operonsc−−
    Flagellin operonsd
  • a −, downregulated 2- to 4-fold; −−, downregulated 5- to 10-fold; −−−, downregulated ≥10-fold; +, upregulated 2- to 9-fold; ++, upregulated 10- to 20-fold; +++, upregulated 20- to 50-fold; ++++, upregulated ≥50-fold. TOB, tobramycin; WT, wild type.

  • b Determined to be resistant in a screen of inactivation mutants reported previously by Schurek et al. (39).

  • c pilJK chpABCD pilB pilCD coaE-PA4530 fimU pilVWXY1Y2E PA4958-fimX.

  • d flgFGHIJK PA1442-fliMNOPQR flhB.

  • e The full list of dysregulated genes can be found in Table S1 in the supplemental material.