TABLE 1 .

Strains used^a

Strain	Source and comments (reference)
ATCC 17978	Isolated from cerebral spinal fluid in 1951 from a 4-mo-old with fatal meningitis (61)
HUMC1	Blood and sputum clinical isolate
HUMC4	Deep endotracheal aspirate clinical isolate
HUMC5	Bronchoalveolar lavage clinical isolate
HUMC6	Sputum clinical isolate
HUMC12	Wound infection clinical isolate
R2	Laboratory-derived colistin-resistant mutant derived by serial passage of ATCC 1798 in colistin; pmrBT235I
C14	Polymyxin-resistant clinical isolate

^a HUMC strains are described in reference 42; R2 and C14 are described in reference 43.